Fix constant folding to not error when sub-asts contain unbound variables#1005

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copybara-service merged 1 commit into from
Apr 2, 2026
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Fix constant folding to not error when sub-asts contain unbound variables #1005

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2 changes: 2 additions & 0 deletions optimizer/src/main/java/dev/cel/optimizer/optimizers/BUILD.bazel
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Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -35,6 +35,8 @@ java_library(
"//optimizer:mutable_ast",
"//optimizer:optimization_exception",
"//runtime",
"//runtime:partial_vars",
"//runtime:unknown_attributes",
"@maven//:com_google_errorprone_error_prone_annotations",
"@maven//:com_google_guava_guava",
],
Expand Down
22 changes: 17 additions & 5 deletions optimizer/src/main/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizer.java
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Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -30,7 +30,6 @@
import dev.cel.common.CelValidationException;
import dev.cel.common.Operator;
import dev.cel.common.ast.CelConstant;
import dev.cel.common.ast.CelExpr;
import dev.cel.common.ast.CelExpr.ExprKind.Kind;
import dev.cel.common.ast.CelMutableExpr;
import dev.cel.common.ast.CelMutableExpr.CelMutableCall;
Expand All@@ -47,7 +46,10 @@
import dev.cel.optimizer.AstMutator;
import dev.cel.optimizer.CelAstOptimizer;
import dev.cel.optimizer.CelOptimizationException;
import dev.cel.runtime.CelAttribute.Qualifier;
import dev.cel.runtime.CelAttributePattern;
import dev.cel.runtime.CelEvaluationException;
import dev.cel.runtime.PartialVars;
import java.time.Duration;
import java.time.Instant;
import java.util.ArrayList;
Expand DownExpand Up@@ -282,7 +284,7 @@ private Optional<CelMutableAst> maybeFold(
throws CelOptimizationException {
Object result;
try {
result = evaluateExpr(cel, CelMutableExprConverter.fromMutableExpr(node.expr()));
result = evaluateExpr(cel, node);
} catch (CelValidationException | CelEvaluationException e) {
throw new CelOptimizationException(
"Constant folding failure. Failed to evaluate subtree due to: " + e.getMessage(), e);
Expand DownExpand Up@@ -674,13 +676,23 @@ private CelMutableAst pruneOptionalStructElements(CelMutableAst ast, CelMutableE
}

@CanIgnoreReturnValue
private static Object evaluateExpr(Cel cel, CelExpr expr)
private static Object evaluateExpr(Cel cel, CelNavigableMutableExpr navigableMutableExpr)
throws CelValidationException, CelEvaluationException {
ImmutableList<CelAttributePattern> attributePatterns =
navigableMutableExpr
.allNodes()
.filter(node -> node.getKind().equals(Kind.IDENT))
.map(node -> node.expr().ident().name())
.filter(Qualifier::isLegalIdentifier)
.map(CelAttributePattern::create)
.collect(toImmutableList());
CelAbstractSyntaxTree ast =
CelAbstractSyntaxTree.newParsedAst(expr, CelSource.newBuilder().build());
CelAbstractSyntaxTree.newParsedAst(
CelMutableExprConverter.fromMutableExpr(navigableMutableExpr.expr()),
CelSource.newBuilder().build());
ast = cel.check(ast).getAst();

return cel.createProgram(ast).eval();
return cel.createProgram(ast).eval(PartialVars.of(attributePatterns));
}

/** Options to configure how Constant Folding behave. */
Expand Down
1 change: 1 addition & 0 deletions optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@ java_library(
deps = [
# "//java/com/google/testing/testsize:annotations",
"//bundle:cel",
"//bundle:cel_experimental_factory",
"//common:cel_ast",
"//common:cel_source",
"//common:compiler_common",
Expand Down
97 changes: 71 additions & 26 deletions optimizer/src/test/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizerTest.java
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Original file line numberDiff line numberDiff line change
Expand Up@@ -18,9 +18,12 @@
import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableList;
import com.google.testing.junit.testparameterinjector.TestParameter;
import com.google.testing.junit.testparameterinjector.TestParameterInjector;
import com.google.testing.junit.testparameterinjector.TestParameters;
import dev.cel.bundle.Cel;
import dev.cel.bundle.CelBuilder;
import dev.cel.bundle.CelExperimentalFactory;
import dev.cel.bundle.CelFactory;
import dev.cel.common.CelAbstractSyntaxTree;
import dev.cel.common.CelContainer;
Expand All@@ -47,9 +50,23 @@
@RunWith(TestParameterInjector.class)
public class ConstantFoldingOptimizerTest {
private static final CelOptions CEL_OPTIONS =
CelOptions.current().populateMacroCalls(true).build();
private static final Cel CEL =
CelFactory.standardCelBuilder()
CelOptions.current()
.populateMacroCalls(true)
.enableHeterogeneousNumericComparisons(true)
.build();

private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();

@SuppressWarnings("ImmutableEnumChecker") // test only
private enum RuntimeEnv {
LEGACY(setupEnv(CelFactory.standardCelBuilder())),
PLANNER(setupEnv(CelExperimentalFactory.plannerCelBuilder()));

private final Cel cel;
private final CelOptimizer celOptimizer;

private static Cel setupEnv(CelBuilder celBuilder) {
return celBuilder
.addVar("x", SimpleType.DYN)
.addVar("y", SimpleType.DYN)
.addVar("list_var", ListType.create(SimpleType.STRING))
Expand DownExpand Up@@ -84,13 +101,28 @@ public class ConstantFoldingOptimizerTest {
CelExtensions.sets(CEL_OPTIONS),
CelExtensions.encoders(CEL_OPTIONS))
.build();
}

RuntimeEnv(Cel cel) {
this.cel = cel;
this.celOptimizer =
CelOptimizerFactory.standardCelOptimizerBuilder(cel)
.addAstOptimizers(ConstantFoldingOptimizer.getInstance())
.build();
}

private CelBuilder newCelBuilder() {
switch (this) {
case LEGACY:
return CelFactory.standardCelBuilder();
case PLANNER:
return CelExperimentalFactory.plannerCelBuilder();
}
throw new AssertionError("Unknown RuntimeEnv: " + this);
}
}

private static final CelOptimizer CEL_OPTIMIZER =
CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
.addAstOptimizers(ConstantFoldingOptimizer.getInstance())
.build();

private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();
@TestParameter RuntimeEnv runtimeEnv;

@Test
@TestParameters("{source: 'null', expected: 'null'}")
Expand DownExpand Up@@ -238,9 +270,9 @@ public class ConstantFoldingOptimizerTest {
// TODO: Support folding lists with mixed types. This requires mutable lists.
// @TestParameters("{source: 'dyn([1]) + [1.0]'}")
public void constantFold_success(String source, String expected) throws Exception {
CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(expected);
}
Expand DownExpand Up@@ -285,12 +317,13 @@ public void constantFold_success(String source, String expected) throws Exceptio
public void constantFold_macros_macroCallMetadataPopulated(String source, String expected)
throws Exception {
Cel cel =
CelFactory.standardCelBuilder()
runtimeEnv
.newCelBuilder()
.addVar("x", SimpleType.DYN)
.addVar("y", SimpleType.DYN)
.addMessageTypes(TestAllTypes.getDescriptor())
.setStandardMacros(CelStandardMacro.STANDARD_MACROS)
.setOptions(CelOptions.current().populateMacroCalls(true).build())
.setOptions(CEL_OPTIONS)
.addCompilerLibraries(
CelExtensions.bindings(), CelExtensions.optional(), CelExtensions.comprehensions())
.addRuntimeLibraries(CelExtensions.optional(), CelExtensions.comprehensions())
Expand DownExpand Up@@ -330,12 +363,17 @@ public void constantFold_macros_macroCallMetadataPopulated(String source, String
@TestParameters("{source: 'false ? false : cel.bind(a, true, a)'}")
public void constantFold_macros_withoutMacroCallMetadata(String source) throws Exception {
Cel cel =
CelFactory.standardCelBuilder()
runtimeEnv
.newCelBuilder()
.addVar("x", SimpleType.DYN)
.addVar("y", SimpleType.DYN)
.addMessageTypes(TestAllTypes.getDescriptor())
.setStandardMacros(CelStandardMacro.STANDARD_MACROS)
.setOptions(CelOptions.current().populateMacroCalls(false).build())
.setOptions(
CelOptions.current()
.enableHeterogeneousNumericComparisons(true)
.populateMacroCalls(false)
.build())
.addCompilerLibraries(CelExtensions.bindings(), CelOptionalLibrary.INSTANCE)
.addRuntimeLibraries(CelOptionalLibrary.INSTANCE)
.build();
Expand DownExpand Up@@ -378,21 +416,22 @@ public void constantFold_macros_withoutMacroCallMetadata(String source) throws E
@TestParameters("{source: 'duration(\"1h\")'}")
@TestParameters("{source: '[true].exists(x, x == get_true())'}")
@TestParameters("{source: 'get_list([1, 2]).map(x, x * 2)'}")
@TestParameters("{source: '[(x - 1 > 3) ? (x - 1) : 5].exists(x, x - 1 > 3)'}")
public void constantFold_noOp(String source) throws Exception {
CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(source);
}

@Test
public void constantFold_addFoldableFunction_success() throws Exception {
CelAbstractSyntaxTree ast = CEL.compile("get_true() == get_true()").getAst();
CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("get_true() == get_true()").getAst();
ConstantFoldingOptions options =
ConstantFoldingOptions.newBuilder().addFoldableFunctions("get_true").build();
CelOptimizer optimizer =
CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
CelOptimizerFactory.standardCelOptimizerBuilder(runtimeEnv.cel)
.addAstOptimizers(ConstantFoldingOptimizer.newInstance(options))
.build();

Expand All@@ -403,7 +442,7 @@ public void constantFold_addFoldableFunction_success() throws Exception {

@Test
public void constantFold_withExpectedResultTypeSet_success() throws Exception {
Cel cel = CelFactory.standardCelBuilder().setResultType(SimpleType.STRING).build();
Cel cel = runtimeEnv.newCelBuilder().setResultType(SimpleType.STRING).build();
CelOptimizer optimizer =
CelOptimizerFactory.standardCelOptimizerBuilder(cel)
.addAstOptimizers(ConstantFoldingOptimizer.getInstance())
Expand All@@ -419,10 +458,11 @@ public void constantFold_withExpectedResultTypeSet_success() throws Exception {
public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNotSet()
throws Exception {
Cel cel =
CelFactory.standardCelBuilder()
runtimeEnv
.newCelBuilder()
.addVar("x", SimpleType.DYN)
.setStandardMacros(CelStandardMacro.STANDARD_MACROS)
.setOptions(CelOptions.current().populateMacroCalls(true).build())
.setOptions(CEL_OPTIONS)
.build();
CelOptimizer celOptimizer =
CelOptimizerFactory.standardCelOptimizerBuilder(cel)
Expand DownExpand Up@@ -492,9 +532,9 @@ public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNot

@Test
public void constantFold_astProducesConsistentlyNumberedIds() throws Exception {
CelAbstractSyntaxTree ast = CEL.compile("[1] + [2] + [3]").getAst();
CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("[1] + [2] + [3]").getAst();

CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

assertThat(optimizedAst.getExpr().toString())
.isEqualTo(
Expand All@@ -515,8 +555,13 @@ public void iterationLimitReached_throws() throws Exception {
sb.append(" + ").append(i);
} // 0 + 1 + 2 + 3 + ... 200
Cel cel =
CelFactory.standardCelBuilder()
.setOptions(CelOptions.current().maxParseRecursionDepth(200).build())
runtimeEnv
.newCelBuilder()
.setOptions(
CelOptions.current()
.enableHeterogeneousNumericComparisons(true)
.maxParseRecursionDepth(200)
.build())
.build();
CelAbstractSyntaxTree ast = cel.compile(sb.toString()).getAst();
CelOptimizer optimizer =
Expand Down
7 changes: 6 additions & 1 deletion runtime/src/main/java/dev/cel/runtime/PartialVars.java
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Original file line numberDiff line numberDiff line change
Expand Up@@ -37,7 +37,12 @@ public abstract class PartialVars {

/** Constructs a new {@code PartialVars} from one or more {@link CelAttributePattern}s. */
public static PartialVars of(CelAttributePattern... unknownAttributes) {
return of((unused) -> Optional.empty(), ImmutableList.copyOf(unknownAttributes));
return of(ImmutableList.copyOf(unknownAttributes));
}

/** Constructs a new {@code PartialVars} from a list of {@link CelAttributePattern}s. */
public static PartialVars of(Iterable<CelAttributePattern> unknownAttributes) {
return of((unused) -> Optional.empty(), unknownAttributes);
}

/**
Expand Down
Loading
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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Fix constant folding to not error when sub-asts contain unbound variables#1005

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 Merged

copybara-service
merged 1 commit into

from

Apr 2, 2026
 Merged


Fix constant folding to not error when sub-asts contain unbound variables
#1005
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2 changes: 2 additions & 0 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/BUILD.bazel

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -35,6 +35,8 @@ java_library(
 "//optimizer:mutable_ast",
 "//optimizer:optimization_exception",
 "//runtime",
 "//runtime:partial_vars",
 "//runtime:unknown_attributes",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 ],
Expand Down

22 changes: 17 additions & 5 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizer.java

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -30,7 +30,6 @@
import dev.cel.common.CelValidationException;
import dev.cel.common.Operator;
import dev.cel.common.ast.CelConstant;
import dev.cel.common.ast.CelExpr;
import dev.cel.common.ast.CelExpr.ExprKind.Kind;
import dev.cel.common.ast.CelMutableExpr;
import dev.cel.common.ast.CelMutableExpr.CelMutableCall;
Expand All@@ -47,7 +46,10 @@
import dev.cel.optimizer.AstMutator;
import dev.cel.optimizer.CelAstOptimizer;
import dev.cel.optimizer.CelOptimizationException;
import dev.cel.runtime.CelAttribute.Qualifier;
import dev.cel.runtime.CelAttributePattern;
import dev.cel.runtime.CelEvaluationException;
import dev.cel.runtime.PartialVars;
import java.time.Duration;
import java.time.Instant;
import java.util.ArrayList;
Expand DownExpand Up@@ -282,7 +284,7 @@ private Optional<CelMutableAst> maybeFold(
 throws CelOptimizationException {
 Object result;
 try {
 result = evaluateExpr(cel, CelMutableExprConverter.fromMutableExpr(node.expr()));
 result = evaluateExpr(cel, node);
 } catch (CelValidationException | CelEvaluationException e) {
 throw new CelOptimizationException(
 "Constant folding failure. Failed to evaluate subtree due to: " + e.getMessage(), e);
Expand DownExpand Up@@ -674,13 +676,23 @@ private CelMutableAst pruneOptionalStructElements(CelMutableAst ast, CelMutableE
 }

 @CanIgnoreReturnValue
 private static Object evaluateExpr(Cel cel, CelExpr expr)
 private static Object evaluateExpr(Cel cel, CelNavigableMutableExpr navigableMutableExpr)
 throws CelValidationException, CelEvaluationException {
 ImmutableList<CelAttributePattern> attributePatterns =
 navigableMutableExpr
 .allNodes()
 .filter(node -> node.getKind().equals(Kind.IDENT))
 .map(node -> node.expr().ident().name())
 .filter(Qualifier::isLegalIdentifier)
 .map(CelAttributePattern::create)
 .collect(toImmutableList());
 CelAbstractSyntaxTree ast =
 CelAbstractSyntaxTree.newParsedAst(expr, CelSource.newBuilder().build());
 CelAbstractSyntaxTree.newParsedAst(
 CelMutableExprConverter.fromMutableExpr(navigableMutableExpr.expr()),
 CelSource.newBuilder().build());
 ast = cel.check(ast).getAst();

 return cel.createProgram(ast).eval();
 return cel.createProgram(ast).eval(PartialVars.of(attributePatterns));
 }

 /** Options to configure how Constant Folding behave. */
Expand Down

1 change: 1 addition & 0 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@ java_library(
 deps = [
 # "//java/com/google/testing/testsize:annotations",
 "//bundle:cel",
 "//bundle:cel_experimental_factory",
 "//common:cel_ast",
 "//common:cel_source",
 "//common:compiler_common",
Expand Down

97 changes: 71 additions & 26 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizerTest.java

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -18,9 +18,12 @@
import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableList;
import com.google.testing.junit.testparameterinjector.TestParameter;
import com.google.testing.junit.testparameterinjector.TestParameterInjector;
import com.google.testing.junit.testparameterinjector.TestParameters;
import dev.cel.bundle.Cel;
import dev.cel.bundle.CelBuilder;
import dev.cel.bundle.CelExperimentalFactory;
import dev.cel.bundle.CelFactory;
import dev.cel.common.CelAbstractSyntaxTree;
import dev.cel.common.CelContainer;
Expand All@@ -47,9 +50,23 @@
@RunWith(TestParameterInjector.class)
public class ConstantFoldingOptimizerTest {
 private static final CelOptions CEL_OPTIONS =
 CelOptions.current().populateMacroCalls(true).build();
 private static final Cel CEL =
 CelFactory.standardCelBuilder()
 CelOptions.current()
 .populateMacroCalls(true)
 .enableHeterogeneousNumericComparisons(true)
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();

 @SuppressWarnings("ImmutableEnumChecker") // test only
 private enum RuntimeEnv {
 LEGACY(setupEnv(CelFactory.standardCelBuilder())),
 PLANNER(setupEnv(CelExperimentalFactory.plannerCelBuilder()));

 private final Cel cel;
 private final CelOptimizer celOptimizer;

 private static Cel setupEnv(CelBuilder celBuilder) {
 return celBuilder
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addVar("list_var", ListType.create(SimpleType.STRING))
Expand DownExpand Up@@ -84,13 +101,28 @@ public class ConstantFoldingOptimizerTest {
 CelExtensions.sets(CEL_OPTIONS),
 CelExtensions.encoders(CEL_OPTIONS))
 .build();
 }

 RuntimeEnv(Cel cel) {
 this.cel = cel;
 this.celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();
 }

 private CelBuilder newCelBuilder() {
 switch (this) {
 case LEGACY:
 return CelFactory.standardCelBuilder();
 case PLANNER:
 return CelExperimentalFactory.plannerCelBuilder();
 }
 throw new AssertionError("Unknown RuntimeEnv: " + this);
 }
 }

 private static final CelOptimizer CEL_OPTIMIZER =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();
 @TestParameter RuntimeEnv runtimeEnv;

 @Test
 @TestParameters("{source: 'null', expected: 'null'}")
Expand DownExpand Up@@ -238,9 +270,9 @@ public class ConstantFoldingOptimizerTest {
 // TODO: Support folding lists with mixed types. This requires mutable lists.
 // @TestParameters("{source: 'dyn([1]) + [1.0]'}")
 public void constantFold_success(String source, String expected) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(expected);
 }
Expand DownExpand Up@@ -285,12 +317,13 @@ public void constantFold_success(String source, String expected) throws Exceptio
 public void constantFold_macros_macroCallMetadataPopulated(String source, String expected)
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .addCompilerLibraries(
 CelExtensions.bindings(), CelExtensions.optional(), CelExtensions.comprehensions())
 .addRuntimeLibraries(CelExtensions.optional(), CelExtensions.comprehensions())
Expand DownExpand Up@@ -330,12 +363,17 @@ public void constantFold_macros_macroCallMetadataPopulated(String source, String
 @TestParameters("{source: 'false ? false : cel.bind(a, true, a)'}")
 public void constantFold_macros_withoutMacroCallMetadata(String source) throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(false).build())
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .populateMacroCalls(false)
 .build())
 .addCompilerLibraries(CelExtensions.bindings(), CelOptionalLibrary.INSTANCE)
 .addRuntimeLibraries(CelOptionalLibrary.INSTANCE)
 .build();
Expand DownExpand Up@@ -378,21 +416,22 @@ public void constantFold_macros_withoutMacroCallMetadata(String source) throws E
 @TestParameters("{source: 'duration(\"1h\")'}")
 @TestParameters("{source: '[true].exists(x, x == get_true())'}")
 @TestParameters("{source: 'get_list([1, 2]).map(x, x * 2)'}")
 @TestParameters("{source: '[(x - 1 > 3) ? (x - 1) : 5].exists(x, x - 1 > 3)'}")
 public void constantFold_noOp(String source) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(source);
 }

 @Test
 public void constantFold_addFoldableFunction_success() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("get_true() == get_true()").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("get_true() == get_true()").getAst();
 ConstantFoldingOptions options =
 ConstantFoldingOptions.newBuilder().addFoldableFunctions("get_true").build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 CelOptimizerFactory.standardCelOptimizerBuilder(runtimeEnv.cel)
 .addAstOptimizers(ConstantFoldingOptimizer.newInstance(options))
 .build();

Expand All@@ -403,7 +442,7 @@ public void constantFold_addFoldableFunction_success() throws Exception {

 @Test
 public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 Cel cel = CelFactory.standardCelBuilder().setResultType(SimpleType.STRING).build();
 Cel cel = runtimeEnv.newCelBuilder().setResultType(SimpleType.STRING).build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
Expand All@@ -419,10 +458,11 @@ public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNotSet()
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .build();
 CelOptimizer celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
Expand DownExpand Up@@ -492,9 +532,9 @@ public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNot

 @Test
 public void constantFold_astProducesConsistentlyNumberedIds() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("[1] + [2] + [3]").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("[1] + [2] + [3]").getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(optimizedAst.getExpr().toString())
 .isEqualTo(
Expand All@@ -515,8 +555,13 @@ public void iterationLimitReached_throws() throws Exception {
 sb.append(" + ").append(i);
 } // 0 + 1 + 2 + 3 + ... 200
 Cel cel =
 CelFactory.standardCelBuilder()
 .setOptions(CelOptions.current().maxParseRecursionDepth(200).build())
 runtimeEnv
 .newCelBuilder()
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .maxParseRecursionDepth(200)
 .build())
 .build();
 CelAbstractSyntaxTree ast = cel.compile(sb.toString()).getAst();
 CelOptimizer optimizer =
Expand Down

7 changes: 6 additions & 1 deletion
runtime/src/main/java/dev/cel/runtime/PartialVars.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -37,7 +37,12 @@ public abstract class PartialVars {

 /** Constructs a new {@code PartialVars} from one or more {@link CelAttributePattern}s. */
 public static PartialVars of(CelAttributePattern... unknownAttributes) {
 return of((unused) -> Optional.empty(), ImmutableList.copyOf(unknownAttributes));
 return of(ImmutableList.copyOf(unknownAttributes));
 }

 /** Constructs a new {@code PartialVars} from a list of {@link CelAttributePattern}s. */
 public static PartialVars of(Iterable<CelAttributePattern> unknownAttributes) {
 return of((unused) -> Optional.empty(), unknownAttributes);
 }

 /**
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Fix constant folding to not error when sub-asts contain unbound variables#1005

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copybara-service
merged 1 commit into

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Apr 2, 2026
 Merged


Fix constant folding to not error when sub-asts contain unbound variables
#1005
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2 changes: 2 additions & 0 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/BUILD.bazel

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -35,6 +35,8 @@ java_library(
 "//optimizer:mutable_ast",
 "//optimizer:optimization_exception",
 "//runtime",
 "//runtime:partial_vars",
 "//runtime:unknown_attributes",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 ],
Expand Down

22 changes: 17 additions & 5 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizer.java

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -30,7 +30,6 @@
import dev.cel.common.CelValidationException;
import dev.cel.common.Operator;
import dev.cel.common.ast.CelConstant;
import dev.cel.common.ast.CelExpr;
import dev.cel.common.ast.CelExpr.ExprKind.Kind;
import dev.cel.common.ast.CelMutableExpr;
import dev.cel.common.ast.CelMutableExpr.CelMutableCall;
Expand All@@ -47,7 +46,10 @@
import dev.cel.optimizer.AstMutator;
import dev.cel.optimizer.CelAstOptimizer;
import dev.cel.optimizer.CelOptimizationException;
import dev.cel.runtime.CelAttribute.Qualifier;
import dev.cel.runtime.CelAttributePattern;
import dev.cel.runtime.CelEvaluationException;
import dev.cel.runtime.PartialVars;
import java.time.Duration;
import java.time.Instant;
import java.util.ArrayList;
Expand DownExpand Up@@ -282,7 +284,7 @@ private Optional<CelMutableAst> maybeFold(
 throws CelOptimizationException {
 Object result;
 try {
 result = evaluateExpr(cel, CelMutableExprConverter.fromMutableExpr(node.expr()));
 result = evaluateExpr(cel, node);
 } catch (CelValidationException | CelEvaluationException e) {
 throw new CelOptimizationException(
 "Constant folding failure. Failed to evaluate subtree due to: " + e.getMessage(), e);
Expand DownExpand Up@@ -674,13 +676,23 @@ private CelMutableAst pruneOptionalStructElements(CelMutableAst ast, CelMutableE
 }

 @CanIgnoreReturnValue
 private static Object evaluateExpr(Cel cel, CelExpr expr)
 private static Object evaluateExpr(Cel cel, CelNavigableMutableExpr navigableMutableExpr)
 throws CelValidationException, CelEvaluationException {
 ImmutableList<CelAttributePattern> attributePatterns =
 navigableMutableExpr
 .allNodes()
 .filter(node -> node.getKind().equals(Kind.IDENT))
 .map(node -> node.expr().ident().name())
 .filter(Qualifier::isLegalIdentifier)
 .map(CelAttributePattern::create)
 .collect(toImmutableList());
 CelAbstractSyntaxTree ast =
 CelAbstractSyntaxTree.newParsedAst(expr, CelSource.newBuilder().build());
 CelAbstractSyntaxTree.newParsedAst(
 CelMutableExprConverter.fromMutableExpr(navigableMutableExpr.expr()),
 CelSource.newBuilder().build());
 ast = cel.check(ast).getAst();

 return cel.createProgram(ast).eval();
 return cel.createProgram(ast).eval(PartialVars.of(attributePatterns));
 }

 /** Options to configure how Constant Folding behave. */
Expand Down

1 change: 1 addition & 0 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@ java_library(
 deps = [
 # "//java/com/google/testing/testsize:annotations",
 "//bundle:cel",
 "//bundle:cel_experimental_factory",
 "//common:cel_ast",
 "//common:cel_source",
 "//common:compiler_common",
Expand Down

97 changes: 71 additions & 26 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizerTest.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -18,9 +18,12 @@
import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableList;
import com.google.testing.junit.testparameterinjector.TestParameter;
import com.google.testing.junit.testparameterinjector.TestParameterInjector;
import com.google.testing.junit.testparameterinjector.TestParameters;
import dev.cel.bundle.Cel;
import dev.cel.bundle.CelBuilder;
import dev.cel.bundle.CelExperimentalFactory;
import dev.cel.bundle.CelFactory;
import dev.cel.common.CelAbstractSyntaxTree;
import dev.cel.common.CelContainer;
Expand All@@ -47,9 +50,23 @@
@RunWith(TestParameterInjector.class)
public class ConstantFoldingOptimizerTest {
 private static final CelOptions CEL_OPTIONS =
 CelOptions.current().populateMacroCalls(true).build();
 private static final Cel CEL =
 CelFactory.standardCelBuilder()
 CelOptions.current()
 .populateMacroCalls(true)
 .enableHeterogeneousNumericComparisons(true)
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();

 @SuppressWarnings("ImmutableEnumChecker") // test only
 private enum RuntimeEnv {
 LEGACY(setupEnv(CelFactory.standardCelBuilder())),
 PLANNER(setupEnv(CelExperimentalFactory.plannerCelBuilder()));

 private final Cel cel;
 private final CelOptimizer celOptimizer;

 private static Cel setupEnv(CelBuilder celBuilder) {
 return celBuilder
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addVar("list_var", ListType.create(SimpleType.STRING))
Expand DownExpand Up@@ -84,13 +101,28 @@ public class ConstantFoldingOptimizerTest {
 CelExtensions.sets(CEL_OPTIONS),
 CelExtensions.encoders(CEL_OPTIONS))
 .build();
 }

 RuntimeEnv(Cel cel) {
 this.cel = cel;
 this.celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();
 }

 private CelBuilder newCelBuilder() {
 switch (this) {
 case LEGACY:
 return CelFactory.standardCelBuilder();
 case PLANNER:
 return CelExperimentalFactory.plannerCelBuilder();
 }
 throw new AssertionError("Unknown RuntimeEnv: " + this);
 }
 }

 private static final CelOptimizer CEL_OPTIMIZER =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();
 @TestParameter RuntimeEnv runtimeEnv;

 @Test
 @TestParameters("{source: 'null', expected: 'null'}")
Expand DownExpand Up@@ -238,9 +270,9 @@ public class ConstantFoldingOptimizerTest {
 // TODO: Support folding lists with mixed types. This requires mutable lists.
 // @TestParameters("{source: 'dyn([1]) + [1.0]'}")
 public void constantFold_success(String source, String expected) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(expected);
 }
Expand DownExpand Up@@ -285,12 +317,13 @@ public void constantFold_success(String source, String expected) throws Exceptio
 public void constantFold_macros_macroCallMetadataPopulated(String source, String expected)
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .addCompilerLibraries(
 CelExtensions.bindings(), CelExtensions.optional(), CelExtensions.comprehensions())
 .addRuntimeLibraries(CelExtensions.optional(), CelExtensions.comprehensions())
Expand DownExpand Up@@ -330,12 +363,17 @@ public void constantFold_macros_macroCallMetadataPopulated(String source, String
 @TestParameters("{source: 'false ? false : cel.bind(a, true, a)'}")
 public void constantFold_macros_withoutMacroCallMetadata(String source) throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(false).build())
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .populateMacroCalls(false)
 .build())
 .addCompilerLibraries(CelExtensions.bindings(), CelOptionalLibrary.INSTANCE)
 .addRuntimeLibraries(CelOptionalLibrary.INSTANCE)
 .build();
Expand DownExpand Up@@ -378,21 +416,22 @@ public void constantFold_macros_withoutMacroCallMetadata(String source) throws E
 @TestParameters("{source: 'duration(\"1h\")'}")
 @TestParameters("{source: '[true].exists(x, x == get_true())'}")
 @TestParameters("{source: 'get_list([1, 2]).map(x, x * 2)'}")
 @TestParameters("{source: '[(x - 1 > 3) ? (x - 1) : 5].exists(x, x - 1 > 3)'}")
 public void constantFold_noOp(String source) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(source);
 }

 @Test
 public void constantFold_addFoldableFunction_success() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("get_true() == get_true()").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("get_true() == get_true()").getAst();
 ConstantFoldingOptions options =
 ConstantFoldingOptions.newBuilder().addFoldableFunctions("get_true").build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 CelOptimizerFactory.standardCelOptimizerBuilder(runtimeEnv.cel)
 .addAstOptimizers(ConstantFoldingOptimizer.newInstance(options))
 .build();

Expand All@@ -403,7 +442,7 @@ public void constantFold_addFoldableFunction_success() throws Exception {

 @Test
 public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 Cel cel = CelFactory.standardCelBuilder().setResultType(SimpleType.STRING).build();
 Cel cel = runtimeEnv.newCelBuilder().setResultType(SimpleType.STRING).build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
Expand All@@ -419,10 +458,11 @@ public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNotSet()
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .build();
 CelOptimizer celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
Expand DownExpand Up@@ -492,9 +532,9 @@ public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNot

 @Test
 public void constantFold_astProducesConsistentlyNumberedIds() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("[1] + [2] + [3]").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("[1] + [2] + [3]").getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(optimizedAst.getExpr().toString())
 .isEqualTo(
Expand All@@ -515,8 +555,13 @@ public void iterationLimitReached_throws() throws Exception {
 sb.append(" + ").append(i);
 } // 0 + 1 + 2 + 3 + ... 200
 Cel cel =
 CelFactory.standardCelBuilder()
 .setOptions(CelOptions.current().maxParseRecursionDepth(200).build())
 runtimeEnv
 .newCelBuilder()
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .maxParseRecursionDepth(200)
 .build())
 .build();
 CelAbstractSyntaxTree ast = cel.compile(sb.toString()).getAst();
 CelOptimizer optimizer =
Expand Down

7 changes: 6 additions & 1 deletion
runtime/src/main/java/dev/cel/runtime/PartialVars.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -37,7 +37,12 @@ public abstract class PartialVars {

 /** Constructs a new {@code PartialVars} from one or more {@link CelAttributePattern}s. */
 public static PartialVars of(CelAttributePattern... unknownAttributes) {
 return of((unused) -> Optional.empty(), ImmutableList.copyOf(unknownAttributes));
 return of(ImmutableList.copyOf(unknownAttributes));
 }

 /** Constructs a new {@code PartialVars} from a list of {@link CelAttributePattern}s. */
 public static PartialVars of(Iterable<CelAttributePattern> unknownAttributes) {
 return of((unused) -> Optional.empty(), unknownAttributes);
 }

 /**
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Fix constant folding to not error when sub-asts contain unbound variables#1005

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 Merged

copybara-service
merged 1 commit into

from

Apr 2, 2026
 Merged


Fix constant folding to not error when sub-asts contain unbound variables
#1005
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2 changes: 2 additions & 0 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -35,6 +35,8 @@ java_library(
 "//optimizer:mutable_ast",
 "//optimizer:optimization_exception",
 "//runtime",
 "//runtime:partial_vars",
 "//runtime:unknown_attributes",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 ],
Expand Down

22 changes: 17 additions & 5 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizer.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -30,7 +30,6 @@
import dev.cel.common.CelValidationException;
import dev.cel.common.Operator;
import dev.cel.common.ast.CelConstant;
import dev.cel.common.ast.CelExpr;
import dev.cel.common.ast.CelExpr.ExprKind.Kind;
import dev.cel.common.ast.CelMutableExpr;
import dev.cel.common.ast.CelMutableExpr.CelMutableCall;
Expand All@@ -47,7 +46,10 @@
import dev.cel.optimizer.AstMutator;
import dev.cel.optimizer.CelAstOptimizer;
import dev.cel.optimizer.CelOptimizationException;
import dev.cel.runtime.CelAttribute.Qualifier;
import dev.cel.runtime.CelAttributePattern;
import dev.cel.runtime.CelEvaluationException;
import dev.cel.runtime.PartialVars;
import java.time.Duration;
import java.time.Instant;
import java.util.ArrayList;
Expand DownExpand Up@@ -282,7 +284,7 @@ private Optional<CelMutableAst> maybeFold(
 throws CelOptimizationException {
 Object result;
 try {
 result = evaluateExpr(cel, CelMutableExprConverter.fromMutableExpr(node.expr()));
 result = evaluateExpr(cel, node);
 } catch (CelValidationException | CelEvaluationException e) {
 throw new CelOptimizationException(
 "Constant folding failure. Failed to evaluate subtree due to: " + e.getMessage(), e);
Expand DownExpand Up@@ -674,13 +676,23 @@ private CelMutableAst pruneOptionalStructElements(CelMutableAst ast, CelMutableE
 }

 @CanIgnoreReturnValue
 private static Object evaluateExpr(Cel cel, CelExpr expr)
 private static Object evaluateExpr(Cel cel, CelNavigableMutableExpr navigableMutableExpr)
 throws CelValidationException, CelEvaluationException {
 ImmutableList<CelAttributePattern> attributePatterns =
 navigableMutableExpr
 .allNodes()
 .filter(node -> node.getKind().equals(Kind.IDENT))
 .map(node -> node.expr().ident().name())
 .filter(Qualifier::isLegalIdentifier)
 .map(CelAttributePattern::create)
 .collect(toImmutableList());
 CelAbstractSyntaxTree ast =
 CelAbstractSyntaxTree.newParsedAst(expr, CelSource.newBuilder().build());
 CelAbstractSyntaxTree.newParsedAst(
 CelMutableExprConverter.fromMutableExpr(navigableMutableExpr.expr()),
 CelSource.newBuilder().build());
 ast = cel.check(ast).getAst();

 return cel.createProgram(ast).eval();
 return cel.createProgram(ast).eval(PartialVars.of(attributePatterns));
 }

 /** Options to configure how Constant Folding behave. */
Expand Down

1 change: 1 addition & 0 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@ java_library(
 deps = [
 # "//java/com/google/testing/testsize:annotations",
 "//bundle:cel",
 "//bundle:cel_experimental_factory",
 "//common:cel_ast",
 "//common:cel_source",
 "//common:compiler_common",
Expand Down

97 changes: 71 additions & 26 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizerTest.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -18,9 +18,12 @@
import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableList;
import com.google.testing.junit.testparameterinjector.TestParameter;
import com.google.testing.junit.testparameterinjector.TestParameterInjector;
import com.google.testing.junit.testparameterinjector.TestParameters;
import dev.cel.bundle.Cel;
import dev.cel.bundle.CelBuilder;
import dev.cel.bundle.CelExperimentalFactory;
import dev.cel.bundle.CelFactory;
import dev.cel.common.CelAbstractSyntaxTree;
import dev.cel.common.CelContainer;
Expand All@@ -47,9 +50,23 @@
@RunWith(TestParameterInjector.class)
public class ConstantFoldingOptimizerTest {
 private static final CelOptions CEL_OPTIONS =
 CelOptions.current().populateMacroCalls(true).build();
 private static final Cel CEL =
 CelFactory.standardCelBuilder()
 CelOptions.current()
 .populateMacroCalls(true)
 .enableHeterogeneousNumericComparisons(true)
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();

 @SuppressWarnings("ImmutableEnumChecker") // test only
 private enum RuntimeEnv {
 LEGACY(setupEnv(CelFactory.standardCelBuilder())),
 PLANNER(setupEnv(CelExperimentalFactory.plannerCelBuilder()));

 private final Cel cel;
 private final CelOptimizer celOptimizer;

 private static Cel setupEnv(CelBuilder celBuilder) {
 return celBuilder
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addVar("list_var", ListType.create(SimpleType.STRING))
Expand DownExpand Up@@ -84,13 +101,28 @@ public class ConstantFoldingOptimizerTest {
 CelExtensions.sets(CEL_OPTIONS),
 CelExtensions.encoders(CEL_OPTIONS))
 .build();
 }

 RuntimeEnv(Cel cel) {
 this.cel = cel;
 this.celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();
 }

 private CelBuilder newCelBuilder() {
 switch (this) {
 case LEGACY:
 return CelFactory.standardCelBuilder();
 case PLANNER:
 return CelExperimentalFactory.plannerCelBuilder();
 }
 throw new AssertionError("Unknown RuntimeEnv: " + this);
 }
 }

 private static final CelOptimizer CEL_OPTIMIZER =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();
 @TestParameter RuntimeEnv runtimeEnv;

 @Test
 @TestParameters("{source: 'null', expected: 'null'}")
Expand DownExpand Up@@ -238,9 +270,9 @@ public class ConstantFoldingOptimizerTest {
 // TODO: Support folding lists with mixed types. This requires mutable lists.
 // @TestParameters("{source: 'dyn([1]) + [1.0]'}")
 public void constantFold_success(String source, String expected) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(expected);
 }
Expand DownExpand Up@@ -285,12 +317,13 @@ public void constantFold_success(String source, String expected) throws Exceptio
 public void constantFold_macros_macroCallMetadataPopulated(String source, String expected)
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .addCompilerLibraries(
 CelExtensions.bindings(), CelExtensions.optional(), CelExtensions.comprehensions())
 .addRuntimeLibraries(CelExtensions.optional(), CelExtensions.comprehensions())
Expand DownExpand Up@@ -330,12 +363,17 @@ public void constantFold_macros_macroCallMetadataPopulated(String source, String
 @TestParameters("{source: 'false ? false : cel.bind(a, true, a)'}")
 public void constantFold_macros_withoutMacroCallMetadata(String source) throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(false).build())
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .populateMacroCalls(false)
 .build())
 .addCompilerLibraries(CelExtensions.bindings(), CelOptionalLibrary.INSTANCE)
 .addRuntimeLibraries(CelOptionalLibrary.INSTANCE)
 .build();
Expand DownExpand Up@@ -378,21 +416,22 @@ public void constantFold_macros_withoutMacroCallMetadata(String source) throws E
 @TestParameters("{source: 'duration(\"1h\")'}")
 @TestParameters("{source: '[true].exists(x, x == get_true())'}")
 @TestParameters("{source: 'get_list([1, 2]).map(x, x * 2)'}")
 @TestParameters("{source: '[(x - 1 > 3) ? (x - 1) : 5].exists(x, x - 1 > 3)'}")
 public void constantFold_noOp(String source) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(source);
 }

 @Test
 public void constantFold_addFoldableFunction_success() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("get_true() == get_true()").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("get_true() == get_true()").getAst();
 ConstantFoldingOptions options =
 ConstantFoldingOptions.newBuilder().addFoldableFunctions("get_true").build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 CelOptimizerFactory.standardCelOptimizerBuilder(runtimeEnv.cel)
 .addAstOptimizers(ConstantFoldingOptimizer.newInstance(options))
 .build();

Expand All@@ -403,7 +442,7 @@ public void constantFold_addFoldableFunction_success() throws Exception {

 @Test
 public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 Cel cel = CelFactory.standardCelBuilder().setResultType(SimpleType.STRING).build();
 Cel cel = runtimeEnv.newCelBuilder().setResultType(SimpleType.STRING).build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
Expand All@@ -419,10 +458,11 @@ public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNotSet()
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .build();
 CelOptimizer celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
Expand DownExpand Up@@ -492,9 +532,9 @@ public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNot

 @Test
 public void constantFold_astProducesConsistentlyNumberedIds() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("[1] + [2] + [3]").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("[1] + [2] + [3]").getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(optimizedAst.getExpr().toString())
 .isEqualTo(
Expand All@@ -515,8 +555,13 @@ public void iterationLimitReached_throws() throws Exception {
 sb.append(" + ").append(i);
 } // 0 + 1 + 2 + 3 + ... 200
 Cel cel =
 CelFactory.standardCelBuilder()
 .setOptions(CelOptions.current().maxParseRecursionDepth(200).build())
 runtimeEnv
 .newCelBuilder()
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .maxParseRecursionDepth(200)
 .build())
 .build();
 CelAbstractSyntaxTree ast = cel.compile(sb.toString()).getAst();
 CelOptimizer optimizer =
Expand Down

7 changes: 6 additions & 1 deletion
runtime/src/main/java/dev/cel/runtime/PartialVars.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -37,7 +37,12 @@ public abstract class PartialVars {

 /** Constructs a new {@code PartialVars} from one or more {@link CelAttributePattern}s. */
 public static PartialVars of(CelAttributePattern... unknownAttributes) {
 return of((unused) -> Optional.empty(), ImmutableList.copyOf(unknownAttributes));
 return of(ImmutableList.copyOf(unknownAttributes));
 }

 /** Constructs a new {@code PartialVars} from a list of {@link CelAttributePattern}s. */
 public static PartialVars of(Iterable<CelAttributePattern> unknownAttributes) {
 return of((unused) -> Optional.empty(), unknownAttributes);
 }

 /**
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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Fix constant folding to not error when sub-asts contain unbound variables#1005

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 Merged

copybara-service
merged 1 commit into

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Apr 2, 2026
 Merged


Fix constant folding to not error when sub-asts contain unbound variables
#1005
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2 changes: 2 additions & 0 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -35,6 +35,8 @@ java_library(
 "//optimizer:mutable_ast",
 "//optimizer:optimization_exception",
 "//runtime",
 "//runtime:partial_vars",
 "//runtime:unknown_attributes",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 ],
Expand Down

22 changes: 17 additions & 5 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizer.java

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -30,7 +30,6 @@
import dev.cel.common.CelValidationException;
import dev.cel.common.Operator;
import dev.cel.common.ast.CelConstant;
import dev.cel.common.ast.CelExpr;
import dev.cel.common.ast.CelExpr.ExprKind.Kind;
import dev.cel.common.ast.CelMutableExpr;
import dev.cel.common.ast.CelMutableExpr.CelMutableCall;
Expand All@@ -47,7 +46,10 @@
import dev.cel.optimizer.AstMutator;
import dev.cel.optimizer.CelAstOptimizer;
import dev.cel.optimizer.CelOptimizationException;
import dev.cel.runtime.CelAttribute.Qualifier;
import dev.cel.runtime.CelAttributePattern;
import dev.cel.runtime.CelEvaluationException;
import dev.cel.runtime.PartialVars;
import java.time.Duration;
import java.time.Instant;
import java.util.ArrayList;
Expand DownExpand Up@@ -282,7 +284,7 @@ private Optional<CelMutableAst> maybeFold(
 throws CelOptimizationException {
 Object result;
 try {
 result = evaluateExpr(cel, CelMutableExprConverter.fromMutableExpr(node.expr()));
 result = evaluateExpr(cel, node);
 } catch (CelValidationException | CelEvaluationException e) {
 throw new CelOptimizationException(
 "Constant folding failure. Failed to evaluate subtree due to: " + e.getMessage(), e);
Expand DownExpand Up@@ -674,13 +676,23 @@ private CelMutableAst pruneOptionalStructElements(CelMutableAst ast, CelMutableE
 }

 @CanIgnoreReturnValue
 private static Object evaluateExpr(Cel cel, CelExpr expr)
 private static Object evaluateExpr(Cel cel, CelNavigableMutableExpr navigableMutableExpr)
 throws CelValidationException, CelEvaluationException {
 ImmutableList<CelAttributePattern> attributePatterns =
 navigableMutableExpr
 .allNodes()
 .filter(node -> node.getKind().equals(Kind.IDENT))
 .map(node -> node.expr().ident().name())
 .filter(Qualifier::isLegalIdentifier)
 .map(CelAttributePattern::create)
 .collect(toImmutableList());
 CelAbstractSyntaxTree ast =
 CelAbstractSyntaxTree.newParsedAst(expr, CelSource.newBuilder().build());
 CelAbstractSyntaxTree.newParsedAst(
 CelMutableExprConverter.fromMutableExpr(navigableMutableExpr.expr()),
 CelSource.newBuilder().build());
 ast = cel.check(ast).getAst();

 return cel.createProgram(ast).eval();
 return cel.createProgram(ast).eval(PartialVars.of(attributePatterns));
 }

 /** Options to configure how Constant Folding behave. */
Expand Down

1 change: 1 addition & 0 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@ java_library(
 deps = [
 # "//java/com/google/testing/testsize:annotations",
 "//bundle:cel",
 "//bundle:cel_experimental_factory",
 "//common:cel_ast",
 "//common:cel_source",
 "//common:compiler_common",
Expand Down

97 changes: 71 additions & 26 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizerTest.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -18,9 +18,12 @@
import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableList;
import com.google.testing.junit.testparameterinjector.TestParameter;
import com.google.testing.junit.testparameterinjector.TestParameterInjector;
import com.google.testing.junit.testparameterinjector.TestParameters;
import dev.cel.bundle.Cel;
import dev.cel.bundle.CelBuilder;
import dev.cel.bundle.CelExperimentalFactory;
import dev.cel.bundle.CelFactory;
import dev.cel.common.CelAbstractSyntaxTree;
import dev.cel.common.CelContainer;
Expand All@@ -47,9 +50,23 @@
@RunWith(TestParameterInjector.class)
public class ConstantFoldingOptimizerTest {
 private static final CelOptions CEL_OPTIONS =
 CelOptions.current().populateMacroCalls(true).build();
 private static final Cel CEL =
 CelFactory.standardCelBuilder()
 CelOptions.current()
 .populateMacroCalls(true)
 .enableHeterogeneousNumericComparisons(true)
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();

 @SuppressWarnings("ImmutableEnumChecker") // test only
 private enum RuntimeEnv {
 LEGACY(setupEnv(CelFactory.standardCelBuilder())),
 PLANNER(setupEnv(CelExperimentalFactory.plannerCelBuilder()));

 private final Cel cel;
 private final CelOptimizer celOptimizer;

 private static Cel setupEnv(CelBuilder celBuilder) {
 return celBuilder
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addVar("list_var", ListType.create(SimpleType.STRING))
Expand DownExpand Up@@ -84,13 +101,28 @@ public class ConstantFoldingOptimizerTest {
 CelExtensions.sets(CEL_OPTIONS),
 CelExtensions.encoders(CEL_OPTIONS))
 .build();
 }

 RuntimeEnv(Cel cel) {
 this.cel = cel;
 this.celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();
 }

 private CelBuilder newCelBuilder() {
 switch (this) {
 case LEGACY:
 return CelFactory.standardCelBuilder();
 case PLANNER:
 return CelExperimentalFactory.plannerCelBuilder();
 }
 throw new AssertionError("Unknown RuntimeEnv: " + this);
 }
 }

 private static final CelOptimizer CEL_OPTIMIZER =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();
 @TestParameter RuntimeEnv runtimeEnv;

 @Test
 @TestParameters("{source: 'null', expected: 'null'}")
Expand DownExpand Up@@ -238,9 +270,9 @@ public class ConstantFoldingOptimizerTest {
 // TODO: Support folding lists with mixed types. This requires mutable lists.
 // @TestParameters("{source: 'dyn([1]) + [1.0]'}")
 public void constantFold_success(String source, String expected) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(expected);
 }
Expand DownExpand Up@@ -285,12 +317,13 @@ public void constantFold_success(String source, String expected) throws Exceptio
 public void constantFold_macros_macroCallMetadataPopulated(String source, String expected)
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .addCompilerLibraries(
 CelExtensions.bindings(), CelExtensions.optional(), CelExtensions.comprehensions())
 .addRuntimeLibraries(CelExtensions.optional(), CelExtensions.comprehensions())
Expand DownExpand Up@@ -330,12 +363,17 @@ public void constantFold_macros_macroCallMetadataPopulated(String source, String
 @TestParameters("{source: 'false ? false : cel.bind(a, true, a)'}")
 public void constantFold_macros_withoutMacroCallMetadata(String source) throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(false).build())
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .populateMacroCalls(false)
 .build())
 .addCompilerLibraries(CelExtensions.bindings(), CelOptionalLibrary.INSTANCE)
 .addRuntimeLibraries(CelOptionalLibrary.INSTANCE)
 .build();
Expand DownExpand Up@@ -378,21 +416,22 @@ public void constantFold_macros_withoutMacroCallMetadata(String source) throws E
 @TestParameters("{source: 'duration(\"1h\")'}")
 @TestParameters("{source: '[true].exists(x, x == get_true())'}")
 @TestParameters("{source: 'get_list([1, 2]).map(x, x * 2)'}")
 @TestParameters("{source: '[(x - 1 > 3) ? (x - 1) : 5].exists(x, x - 1 > 3)'}")
 public void constantFold_noOp(String source) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(source);
 }

 @Test
 public void constantFold_addFoldableFunction_success() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("get_true() == get_true()").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("get_true() == get_true()").getAst();
 ConstantFoldingOptions options =
 ConstantFoldingOptions.newBuilder().addFoldableFunctions("get_true").build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 CelOptimizerFactory.standardCelOptimizerBuilder(runtimeEnv.cel)
 .addAstOptimizers(ConstantFoldingOptimizer.newInstance(options))
 .build();

Expand All@@ -403,7 +442,7 @@ public void constantFold_addFoldableFunction_success() throws Exception {

 @Test
 public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 Cel cel = CelFactory.standardCelBuilder().setResultType(SimpleType.STRING).build();
 Cel cel = runtimeEnv.newCelBuilder().setResultType(SimpleType.STRING).build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
Expand All@@ -419,10 +458,11 @@ public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNotSet()
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .build();
 CelOptimizer celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
Expand DownExpand Up@@ -492,9 +532,9 @@ public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNot

 @Test
 public void constantFold_astProducesConsistentlyNumberedIds() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("[1] + [2] + [3]").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("[1] + [2] + [3]").getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(optimizedAst.getExpr().toString())
 .isEqualTo(
Expand All@@ -515,8 +555,13 @@ public void iterationLimitReached_throws() throws Exception {
 sb.append(" + ").append(i);
 } // 0 + 1 + 2 + 3 + ... 200
 Cel cel =
 CelFactory.standardCelBuilder()
 .setOptions(CelOptions.current().maxParseRecursionDepth(200).build())
 runtimeEnv
 .newCelBuilder()
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .maxParseRecursionDepth(200)
 .build())
 .build();
 CelAbstractSyntaxTree ast = cel.compile(sb.toString()).getAst();
 CelOptimizer optimizer =
Expand Down

7 changes: 6 additions & 1 deletion
runtime/src/main/java/dev/cel/runtime/PartialVars.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -37,7 +37,12 @@ public abstract class PartialVars {

 /** Constructs a new {@code PartialVars} from one or more {@link CelAttributePattern}s. */
 public static PartialVars of(CelAttributePattern... unknownAttributes) {
 return of((unused) -> Optional.empty(), ImmutableList.copyOf(unknownAttributes));
 return of(ImmutableList.copyOf(unknownAttributes));
 }

 /** Constructs a new {@code PartialVars} from a list of {@link CelAttributePattern}s. */
 public static PartialVars of(Iterable<CelAttributePattern> unknownAttributes) {
 return of((unused) -> Optional.empty(), unknownAttributes);
 }

 /**
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Fix constant folding to not error when sub-asts contain unbound variables#1005

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Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

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privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Merged

copybara-service
merged 1 commit into

from

Apr 2, 2026
 Merged


Fix constant folding to not error when sub-asts contain unbound variables
#1005
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2 changes: 2 additions & 0 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/BUILD.bazel

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Original file line numberDiff line numberDiff line change
Expand Up@@ -35,6 +35,8 @@ java_library(
 "//optimizer:mutable_ast",
 "//optimizer:optimization_exception",
 "//runtime",
 "//runtime:partial_vars",
 "//runtime:unknown_attributes",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 ],
Expand Down

22 changes: 17 additions & 5 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizer.java

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Original file line numberDiff line numberDiff line change
Expand Up@@ -30,7 +30,6 @@
import dev.cel.common.CelValidationException;
import dev.cel.common.Operator;
import dev.cel.common.ast.CelConstant;
import dev.cel.common.ast.CelExpr;
import dev.cel.common.ast.CelExpr.ExprKind.Kind;
import dev.cel.common.ast.CelMutableExpr;
import dev.cel.common.ast.CelMutableExpr.CelMutableCall;
Expand All@@ -47,7 +46,10 @@
import dev.cel.optimizer.AstMutator;
import dev.cel.optimizer.CelAstOptimizer;
import dev.cel.optimizer.CelOptimizationException;
import dev.cel.runtime.CelAttribute.Qualifier;
import dev.cel.runtime.CelAttributePattern;
import dev.cel.runtime.CelEvaluationException;
import dev.cel.runtime.PartialVars;
import java.time.Duration;
import java.time.Instant;
import java.util.ArrayList;
Expand DownExpand Up@@ -282,7 +284,7 @@ private Optional<CelMutableAst> maybeFold(
 throws CelOptimizationException {
 Object result;
 try {
 result = evaluateExpr(cel, CelMutableExprConverter.fromMutableExpr(node.expr()));
 result = evaluateExpr(cel, node);
 } catch (CelValidationException | CelEvaluationException e) {
 throw new CelOptimizationException(
 "Constant folding failure. Failed to evaluate subtree due to: " + e.getMessage(), e);
Expand DownExpand Up@@ -674,13 +676,23 @@ private CelMutableAst pruneOptionalStructElements(CelMutableAst ast, CelMutableE
 }

 @CanIgnoreReturnValue
 private static Object evaluateExpr(Cel cel, CelExpr expr)
 private static Object evaluateExpr(Cel cel, CelNavigableMutableExpr navigableMutableExpr)
 throws CelValidationException, CelEvaluationException {
 ImmutableList<CelAttributePattern> attributePatterns =
 navigableMutableExpr
 .allNodes()
 .filter(node -> node.getKind().equals(Kind.IDENT))
 .map(node -> node.expr().ident().name())
 .filter(Qualifier::isLegalIdentifier)
 .map(CelAttributePattern::create)
 .collect(toImmutableList());
 CelAbstractSyntaxTree ast =
 CelAbstractSyntaxTree.newParsedAst(expr, CelSource.newBuilder().build());
 CelAbstractSyntaxTree.newParsedAst(
 CelMutableExprConverter.fromMutableExpr(navigableMutableExpr.expr()),
 CelSource.newBuilder().build());
 ast = cel.check(ast).getAst();

 return cel.createProgram(ast).eval();
 return cel.createProgram(ast).eval(PartialVars.of(attributePatterns));
 }

 /** Options to configure how Constant Folding behave. */
Expand Down

1 change: 1 addition & 0 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@ java_library(
 deps = [
 # "//java/com/google/testing/testsize:annotations",
 "//bundle:cel",
 "//bundle:cel_experimental_factory",
 "//common:cel_ast",
 "//common:cel_source",
 "//common:compiler_common",
Expand Down

97 changes: 71 additions & 26 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizerTest.java

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -18,9 +18,12 @@
import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableList;
import com.google.testing.junit.testparameterinjector.TestParameter;
import com.google.testing.junit.testparameterinjector.TestParameterInjector;
import com.google.testing.junit.testparameterinjector.TestParameters;
import dev.cel.bundle.Cel;
import dev.cel.bundle.CelBuilder;
import dev.cel.bundle.CelExperimentalFactory;
import dev.cel.bundle.CelFactory;
import dev.cel.common.CelAbstractSyntaxTree;
import dev.cel.common.CelContainer;
Expand All@@ -47,9 +50,23 @@
@RunWith(TestParameterInjector.class)
public class ConstantFoldingOptimizerTest {
 private static final CelOptions CEL_OPTIONS =
 CelOptions.current().populateMacroCalls(true).build();
 private static final Cel CEL =
 CelFactory.standardCelBuilder()
 CelOptions.current()
 .populateMacroCalls(true)
 .enableHeterogeneousNumericComparisons(true)
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();

 @SuppressWarnings("ImmutableEnumChecker") // test only
 private enum RuntimeEnv {
 LEGACY(setupEnv(CelFactory.standardCelBuilder())),
 PLANNER(setupEnv(CelExperimentalFactory.plannerCelBuilder()));

 private final Cel cel;
 private final CelOptimizer celOptimizer;

 private static Cel setupEnv(CelBuilder celBuilder) {
 return celBuilder
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addVar("list_var", ListType.create(SimpleType.STRING))
Expand DownExpand Up@@ -84,13 +101,28 @@ public class ConstantFoldingOptimizerTest {
 CelExtensions.sets(CEL_OPTIONS),
 CelExtensions.encoders(CEL_OPTIONS))
 .build();
 }

 RuntimeEnv(Cel cel) {
 this.cel = cel;
 this.celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();
 }

 private CelBuilder newCelBuilder() {
 switch (this) {
 case LEGACY:
 return CelFactory.standardCelBuilder();
 case PLANNER:
 return CelExperimentalFactory.plannerCelBuilder();
 }
 throw new AssertionError("Unknown RuntimeEnv: " + this);
 }
 }

 private static final CelOptimizer CEL_OPTIMIZER =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();
 @TestParameter RuntimeEnv runtimeEnv;

 @Test
 @TestParameters("{source: 'null', expected: 'null'}")
Expand DownExpand Up@@ -238,9 +270,9 @@ public class ConstantFoldingOptimizerTest {
 // TODO: Support folding lists with mixed types. This requires mutable lists.
 // @TestParameters("{source: 'dyn([1]) + [1.0]'}")
 public void constantFold_success(String source, String expected) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(expected);
 }
Expand DownExpand Up@@ -285,12 +317,13 @@ public void constantFold_success(String source, String expected) throws Exceptio
 public void constantFold_macros_macroCallMetadataPopulated(String source, String expected)
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .addCompilerLibraries(
 CelExtensions.bindings(), CelExtensions.optional(), CelExtensions.comprehensions())
 .addRuntimeLibraries(CelExtensions.optional(), CelExtensions.comprehensions())
Expand DownExpand Up@@ -330,12 +363,17 @@ public void constantFold_macros_macroCallMetadataPopulated(String source, String
 @TestParameters("{source: 'false ? false : cel.bind(a, true, a)'}")
 public void constantFold_macros_withoutMacroCallMetadata(String source) throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(false).build())
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .populateMacroCalls(false)
 .build())
 .addCompilerLibraries(CelExtensions.bindings(), CelOptionalLibrary.INSTANCE)
 .addRuntimeLibraries(CelOptionalLibrary.INSTANCE)
 .build();
Expand DownExpand Up@@ -378,21 +416,22 @@ public void constantFold_macros_withoutMacroCallMetadata(String source) throws E
 @TestParameters("{source: 'duration(\"1h\")'}")
 @TestParameters("{source: '[true].exists(x, x == get_true())'}")
 @TestParameters("{source: 'get_list([1, 2]).map(x, x * 2)'}")
 @TestParameters("{source: '[(x - 1 > 3) ? (x - 1) : 5].exists(x, x - 1 > 3)'}")
 public void constantFold_noOp(String source) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(source);
 }

 @Test
 public void constantFold_addFoldableFunction_success() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("get_true() == get_true()").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("get_true() == get_true()").getAst();
 ConstantFoldingOptions options =
 ConstantFoldingOptions.newBuilder().addFoldableFunctions("get_true").build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 CelOptimizerFactory.standardCelOptimizerBuilder(runtimeEnv.cel)
 .addAstOptimizers(ConstantFoldingOptimizer.newInstance(options))
 .build();

Expand All@@ -403,7 +442,7 @@ public void constantFold_addFoldableFunction_success() throws Exception {

 @Test
 public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 Cel cel = CelFactory.standardCelBuilder().setResultType(SimpleType.STRING).build();
 Cel cel = runtimeEnv.newCelBuilder().setResultType(SimpleType.STRING).build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
Expand All@@ -419,10 +458,11 @@ public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNotSet()
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .build();
 CelOptimizer celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
Expand DownExpand Up@@ -492,9 +532,9 @@ public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNot

 @Test
 public void constantFold_astProducesConsistentlyNumberedIds() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("[1] + [2] + [3]").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("[1] + [2] + [3]").getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(optimizedAst.getExpr().toString())
 .isEqualTo(
Expand All@@ -515,8 +555,13 @@ public void iterationLimitReached_throws() throws Exception {
 sb.append(" + ").append(i);
 } // 0 + 1 + 2 + 3 + ... 200
 Cel cel =
 CelFactory.standardCelBuilder()
 .setOptions(CelOptions.current().maxParseRecursionDepth(200).build())
 runtimeEnv
 .newCelBuilder()
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .maxParseRecursionDepth(200)
 .build())
 .build();
 CelAbstractSyntaxTree ast = cel.compile(sb.toString()).getAst();
 CelOptimizer optimizer =
Expand Down

7 changes: 6 additions & 1 deletion
runtime/src/main/java/dev/cel/runtime/PartialVars.java

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Original file line numberDiff line numberDiff line change
Expand Up@@ -37,7 +37,12 @@ public abstract class PartialVars {

 /** Constructs a new {@code PartialVars} from one or more {@link CelAttributePattern}s. */
 public static PartialVars of(CelAttributePattern... unknownAttributes) {
 return of((unused) -> Optional.empty(), ImmutableList.copyOf(unknownAttributes));
 return of(ImmutableList.copyOf(unknownAttributes));
 }

 /** Constructs a new {@code PartialVars} from a list of {@link CelAttributePattern}s. */
 public static PartialVars of(Iterable<CelAttributePattern> unknownAttributes) {
 return of((unused) -> Optional.empty(), unknownAttributes);
 }

 /**
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Fix constant folding to not error when sub-asts contain unbound variables#1005

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 Merged

copybara-service
merged 1 commit into

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Apr 2, 2026
 Merged


Fix constant folding to not error when sub-asts contain unbound variables
#1005
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2 changes: 2 additions & 0 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -35,6 +35,8 @@ java_library(
 "//optimizer:mutable_ast",
 "//optimizer:optimization_exception",
 "//runtime",
 "//runtime:partial_vars",
 "//runtime:unknown_attributes",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 ],
Expand Down

22 changes: 17 additions & 5 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizer.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -30,7 +30,6 @@
import dev.cel.common.CelValidationException;
import dev.cel.common.Operator;
import dev.cel.common.ast.CelConstant;
import dev.cel.common.ast.CelExpr;
import dev.cel.common.ast.CelExpr.ExprKind.Kind;
import dev.cel.common.ast.CelMutableExpr;
import dev.cel.common.ast.CelMutableExpr.CelMutableCall;
Expand All@@ -47,7 +46,10 @@
import dev.cel.optimizer.AstMutator;
import dev.cel.optimizer.CelAstOptimizer;
import dev.cel.optimizer.CelOptimizationException;
import dev.cel.runtime.CelAttribute.Qualifier;
import dev.cel.runtime.CelAttributePattern;
import dev.cel.runtime.CelEvaluationException;
import dev.cel.runtime.PartialVars;
import java.time.Duration;
import java.time.Instant;
import java.util.ArrayList;
Expand DownExpand Up@@ -282,7 +284,7 @@ private Optional<CelMutableAst> maybeFold(
 throws CelOptimizationException {
 Object result;
 try {
 result = evaluateExpr(cel, CelMutableExprConverter.fromMutableExpr(node.expr()));
 result = evaluateExpr(cel, node);
 } catch (CelValidationException | CelEvaluationException e) {
 throw new CelOptimizationException(
 "Constant folding failure. Failed to evaluate subtree due to: " + e.getMessage(), e);
Expand DownExpand Up@@ -674,13 +676,23 @@ private CelMutableAst pruneOptionalStructElements(CelMutableAst ast, CelMutableE
 }

 @CanIgnoreReturnValue
 private static Object evaluateExpr(Cel cel, CelExpr expr)
 private static Object evaluateExpr(Cel cel, CelNavigableMutableExpr navigableMutableExpr)
 throws CelValidationException, CelEvaluationException {
 ImmutableList<CelAttributePattern> attributePatterns =
 navigableMutableExpr
 .allNodes()
 .filter(node -> node.getKind().equals(Kind.IDENT))
 .map(node -> node.expr().ident().name())
 .filter(Qualifier::isLegalIdentifier)
 .map(CelAttributePattern::create)
 .collect(toImmutableList());
 CelAbstractSyntaxTree ast =
 CelAbstractSyntaxTree.newParsedAst(expr, CelSource.newBuilder().build());
 CelAbstractSyntaxTree.newParsedAst(
 CelMutableExprConverter.fromMutableExpr(navigableMutableExpr.expr()),
 CelSource.newBuilder().build());
 ast = cel.check(ast).getAst();

 return cel.createProgram(ast).eval();
 return cel.createProgram(ast).eval(PartialVars.of(attributePatterns));
 }

 /** Options to configure how Constant Folding behave. */
Expand Down

1 change: 1 addition & 0 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@ java_library(
 deps = [
 # "//java/com/google/testing/testsize:annotations",
 "//bundle:cel",
 "//bundle:cel_experimental_factory",
 "//common:cel_ast",
 "//common:cel_source",
 "//common:compiler_common",
Expand Down

97 changes: 71 additions & 26 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizerTest.java

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -18,9 +18,12 @@
import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableList;
import com.google.testing.junit.testparameterinjector.TestParameter;
import com.google.testing.junit.testparameterinjector.TestParameterInjector;
import com.google.testing.junit.testparameterinjector.TestParameters;
import dev.cel.bundle.Cel;
import dev.cel.bundle.CelBuilder;
import dev.cel.bundle.CelExperimentalFactory;
import dev.cel.bundle.CelFactory;
import dev.cel.common.CelAbstractSyntaxTree;
import dev.cel.common.CelContainer;
Expand All@@ -47,9 +50,23 @@
@RunWith(TestParameterInjector.class)
public class ConstantFoldingOptimizerTest {
 private static final CelOptions CEL_OPTIONS =
 CelOptions.current().populateMacroCalls(true).build();
 private static final Cel CEL =
 CelFactory.standardCelBuilder()
 CelOptions.current()
 .populateMacroCalls(true)
 .enableHeterogeneousNumericComparisons(true)
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();

 @SuppressWarnings("ImmutableEnumChecker") // test only
 private enum RuntimeEnv {
 LEGACY(setupEnv(CelFactory.standardCelBuilder())),
 PLANNER(setupEnv(CelExperimentalFactory.plannerCelBuilder()));

 private final Cel cel;
 private final CelOptimizer celOptimizer;

 private static Cel setupEnv(CelBuilder celBuilder) {
 return celBuilder
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addVar("list_var", ListType.create(SimpleType.STRING))
Expand DownExpand Up@@ -84,13 +101,28 @@ public class ConstantFoldingOptimizerTest {
 CelExtensions.sets(CEL_OPTIONS),
 CelExtensions.encoders(CEL_OPTIONS))
 .build();
 }

 RuntimeEnv(Cel cel) {
 this.cel = cel;
 this.celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();
 }

 private CelBuilder newCelBuilder() {
 switch (this) {
 case LEGACY:
 return CelFactory.standardCelBuilder();
 case PLANNER:
 return CelExperimentalFactory.plannerCelBuilder();
 }
 throw new AssertionError("Unknown RuntimeEnv: " + this);
 }
 }

 private static final CelOptimizer CEL_OPTIMIZER =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();
 @TestParameter RuntimeEnv runtimeEnv;

 @Test
 @TestParameters("{source: 'null', expected: 'null'}")
Expand DownExpand Up@@ -238,9 +270,9 @@ public class ConstantFoldingOptimizerTest {
 // TODO: Support folding lists with mixed types. This requires mutable lists.
 // @TestParameters("{source: 'dyn([1]) + [1.0]'}")
 public void constantFold_success(String source, String expected) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(expected);
 }
Expand DownExpand Up@@ -285,12 +317,13 @@ public void constantFold_success(String source, String expected) throws Exceptio
 public void constantFold_macros_macroCallMetadataPopulated(String source, String expected)
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .addCompilerLibraries(
 CelExtensions.bindings(), CelExtensions.optional(), CelExtensions.comprehensions())
 .addRuntimeLibraries(CelExtensions.optional(), CelExtensions.comprehensions())
Expand DownExpand Up@@ -330,12 +363,17 @@ public void constantFold_macros_macroCallMetadataPopulated(String source, String
 @TestParameters("{source: 'false ? false : cel.bind(a, true, a)'}")
 public void constantFold_macros_withoutMacroCallMetadata(String source) throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(false).build())
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .populateMacroCalls(false)
 .build())
 .addCompilerLibraries(CelExtensions.bindings(), CelOptionalLibrary.INSTANCE)
 .addRuntimeLibraries(CelOptionalLibrary.INSTANCE)
 .build();
Expand DownExpand Up@@ -378,21 +416,22 @@ public void constantFold_macros_withoutMacroCallMetadata(String source) throws E
 @TestParameters("{source: 'duration(\"1h\")'}")
 @TestParameters("{source: '[true].exists(x, x == get_true())'}")
 @TestParameters("{source: 'get_list([1, 2]).map(x, x * 2)'}")
 @TestParameters("{source: '[(x - 1 > 3) ? (x - 1) : 5].exists(x, x - 1 > 3)'}")
 public void constantFold_noOp(String source) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(source);
 }

 @Test
 public void constantFold_addFoldableFunction_success() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("get_true() == get_true()").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("get_true() == get_true()").getAst();
 ConstantFoldingOptions options =
 ConstantFoldingOptions.newBuilder().addFoldableFunctions("get_true").build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 CelOptimizerFactory.standardCelOptimizerBuilder(runtimeEnv.cel)
 .addAstOptimizers(ConstantFoldingOptimizer.newInstance(options))
 .build();

Expand All@@ -403,7 +442,7 @@ public void constantFold_addFoldableFunction_success() throws Exception {

 @Test
 public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 Cel cel = CelFactory.standardCelBuilder().setResultType(SimpleType.STRING).build();
 Cel cel = runtimeEnv.newCelBuilder().setResultType(SimpleType.STRING).build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
Expand All@@ -419,10 +458,11 @@ public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNotSet()
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .build();
 CelOptimizer celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
Expand DownExpand Up@@ -492,9 +532,9 @@ public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNot

 @Test
 public void constantFold_astProducesConsistentlyNumberedIds() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("[1] + [2] + [3]").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("[1] + [2] + [3]").getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(optimizedAst.getExpr().toString())
 .isEqualTo(
Expand All@@ -515,8 +555,13 @@ public void iterationLimitReached_throws() throws Exception {
 sb.append(" + ").append(i);
 } // 0 + 1 + 2 + 3 + ... 200
 Cel cel =
 CelFactory.standardCelBuilder()
 .setOptions(CelOptions.current().maxParseRecursionDepth(200).build())
 runtimeEnv
 .newCelBuilder()
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .maxParseRecursionDepth(200)
 .build())
 .build();
 CelAbstractSyntaxTree ast = cel.compile(sb.toString()).getAst();
 CelOptimizer optimizer =
Expand Down

7 changes: 6 additions & 1 deletion
runtime/src/main/java/dev/cel/runtime/PartialVars.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -37,7 +37,12 @@ public abstract class PartialVars {

 /** Constructs a new {@code PartialVars} from one or more {@link CelAttributePattern}s. */
 public static PartialVars of(CelAttributePattern... unknownAttributes) {
 return of((unused) -> Optional.empty(), ImmutableList.copyOf(unknownAttributes));
 return of(ImmutableList.copyOf(unknownAttributes));
 }

 /** Constructs a new {@code PartialVars} from a list of {@link CelAttributePattern}s. */
 public static PartialVars of(Iterable<CelAttributePattern> unknownAttributes) {
 return of((unused) -> Optional.empty(), unknownAttributes);
 }

 /**
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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Fix constant folding to not error when sub-asts contain unbound variables#1005

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 Merged

copybara-service
merged 1 commit into

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Apr 2, 2026
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Fix constant folding to not error when sub-asts contain unbound variables
#1005
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2 changes: 2 additions & 0 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/BUILD.bazel

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -35,6 +35,8 @@ java_library(
 "//optimizer:mutable_ast",
 "//optimizer:optimization_exception",
 "//runtime",
 "//runtime:partial_vars",
 "//runtime:unknown_attributes",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 ],
Expand Down

22 changes: 17 additions & 5 deletions
optimizer/src/main/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizer.java

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -30,7 +30,6 @@
import dev.cel.common.CelValidationException;
import dev.cel.common.Operator;
import dev.cel.common.ast.CelConstant;
import dev.cel.common.ast.CelExpr;
import dev.cel.common.ast.CelExpr.ExprKind.Kind;
import dev.cel.common.ast.CelMutableExpr;
import dev.cel.common.ast.CelMutableExpr.CelMutableCall;
Expand All@@ -47,7 +46,10 @@
import dev.cel.optimizer.AstMutator;
import dev.cel.optimizer.CelAstOptimizer;
import dev.cel.optimizer.CelOptimizationException;
import dev.cel.runtime.CelAttribute.Qualifier;
import dev.cel.runtime.CelAttributePattern;
import dev.cel.runtime.CelEvaluationException;
import dev.cel.runtime.PartialVars;
import java.time.Duration;
import java.time.Instant;
import java.util.ArrayList;
Expand DownExpand Up@@ -282,7 +284,7 @@ private Optional<CelMutableAst> maybeFold(
 throws CelOptimizationException {
 Object result;
 try {
 result = evaluateExpr(cel, CelMutableExprConverter.fromMutableExpr(node.expr()));
 result = evaluateExpr(cel, node);
 } catch (CelValidationException | CelEvaluationException e) {
 throw new CelOptimizationException(
 "Constant folding failure. Failed to evaluate subtree due to: " + e.getMessage(), e);
Expand DownExpand Up@@ -674,13 +676,23 @@ private CelMutableAst pruneOptionalStructElements(CelMutableAst ast, CelMutableE
 }

 @CanIgnoreReturnValue
 private static Object evaluateExpr(Cel cel, CelExpr expr)
 private static Object evaluateExpr(Cel cel, CelNavigableMutableExpr navigableMutableExpr)
 throws CelValidationException, CelEvaluationException {
 ImmutableList<CelAttributePattern> attributePatterns =
 navigableMutableExpr
 .allNodes()
 .filter(node -> node.getKind().equals(Kind.IDENT))
 .map(node -> node.expr().ident().name())
 .filter(Qualifier::isLegalIdentifier)
 .map(CelAttributePattern::create)
 .collect(toImmutableList());
 CelAbstractSyntaxTree ast =
 CelAbstractSyntaxTree.newParsedAst(expr, CelSource.newBuilder().build());
 CelAbstractSyntaxTree.newParsedAst(
 CelMutableExprConverter.fromMutableExpr(navigableMutableExpr.expr()),
 CelSource.newBuilder().build());
 ast = cel.check(ast).getAst();

 return cel.createProgram(ast).eval();
 return cel.createProgram(ast).eval(PartialVars.of(attributePatterns));
 }

 /** Options to configure how Constant Folding behave. */
Expand Down

1 change: 1 addition & 0 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/BUILD.bazel

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -11,6 +11,7 @@ java_library(
 deps = [
 # "//java/com/google/testing/testsize:annotations",
 "//bundle:cel",
 "//bundle:cel_experimental_factory",
 "//common:cel_ast",
 "//common:cel_source",
 "//common:compiler_common",
Expand Down

97 changes: 71 additions & 26 deletions
optimizer/src/test/java/dev/cel/optimizer/optimizers/ConstantFoldingOptimizerTest.java

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -18,9 +18,12 @@
import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableList;
import com.google.testing.junit.testparameterinjector.TestParameter;
import com.google.testing.junit.testparameterinjector.TestParameterInjector;
import com.google.testing.junit.testparameterinjector.TestParameters;
import dev.cel.bundle.Cel;
import dev.cel.bundle.CelBuilder;
import dev.cel.bundle.CelExperimentalFactory;
import dev.cel.bundle.CelFactory;
import dev.cel.common.CelAbstractSyntaxTree;
import dev.cel.common.CelContainer;
Expand All@@ -47,9 +50,23 @@
@RunWith(TestParameterInjector.class)
public class ConstantFoldingOptimizerTest {
 private static final CelOptions CEL_OPTIONS =
 CelOptions.current().populateMacroCalls(true).build();
 private static final Cel CEL =
 CelFactory.standardCelBuilder()
 CelOptions.current()
 .populateMacroCalls(true)
 .enableHeterogeneousNumericComparisons(true)
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();

 @SuppressWarnings("ImmutableEnumChecker") // test only
 private enum RuntimeEnv {
 LEGACY(setupEnv(CelFactory.standardCelBuilder())),
 PLANNER(setupEnv(CelExperimentalFactory.plannerCelBuilder()));

 private final Cel cel;
 private final CelOptimizer celOptimizer;

 private static Cel setupEnv(CelBuilder celBuilder) {
 return celBuilder
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addVar("list_var", ListType.create(SimpleType.STRING))
Expand DownExpand Up@@ -84,13 +101,28 @@ public class ConstantFoldingOptimizerTest {
 CelExtensions.sets(CEL_OPTIONS),
 CelExtensions.encoders(CEL_OPTIONS))
 .build();
 }

 RuntimeEnv(Cel cel) {
 this.cel = cel;
 this.celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();
 }

 private CelBuilder newCelBuilder() {
 switch (this) {
 case LEGACY:
 return CelFactory.standardCelBuilder();
 case PLANNER:
 return CelExperimentalFactory.plannerCelBuilder();
 }
 throw new AssertionError("Unknown RuntimeEnv: " + this);
 }
 }

 private static final CelOptimizer CEL_OPTIMIZER =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
 .build();

 private static final CelUnparser CEL_UNPARSER = CelUnparserFactory.newUnparser();
 @TestParameter RuntimeEnv runtimeEnv;

 @Test
 @TestParameters("{source: 'null', expected: 'null'}")
Expand DownExpand Up@@ -238,9 +270,9 @@ public class ConstantFoldingOptimizerTest {
 // TODO: Support folding lists with mixed types. This requires mutable lists.
 // @TestParameters("{source: 'dyn([1]) + [1.0]'}")
 public void constantFold_success(String source, String expected) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(expected);
 }
Expand DownExpand Up@@ -285,12 +317,13 @@ public void constantFold_success(String source, String expected) throws Exceptio
 public void constantFold_macros_macroCallMetadataPopulated(String source, String expected)
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .addCompilerLibraries(
 CelExtensions.bindings(), CelExtensions.optional(), CelExtensions.comprehensions())
 .addRuntimeLibraries(CelExtensions.optional(), CelExtensions.comprehensions())
Expand DownExpand Up@@ -330,12 +363,17 @@ public void constantFold_macros_macroCallMetadataPopulated(String source, String
 @TestParameters("{source: 'false ? false : cel.bind(a, true, a)'}")
 public void constantFold_macros_withoutMacroCallMetadata(String source) throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .addVar("y", SimpleType.DYN)
 .addMessageTypes(TestAllTypes.getDescriptor())
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(false).build())
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .populateMacroCalls(false)
 .build())
 .addCompilerLibraries(CelExtensions.bindings(), CelOptionalLibrary.INSTANCE)
 .addRuntimeLibraries(CelOptionalLibrary.INSTANCE)
 .build();
Expand DownExpand Up@@ -378,21 +416,22 @@ public void constantFold_macros_withoutMacroCallMetadata(String source) throws E
 @TestParameters("{source: 'duration(\"1h\")'}")
 @TestParameters("{source: '[true].exists(x, x == get_true())'}")
 @TestParameters("{source: 'get_list([1, 2]).map(x, x * 2)'}")
 @TestParameters("{source: '[(x - 1 > 3) ? (x - 1) : 5].exists(x, x - 1 > 3)'}")
 public void constantFold_noOp(String source) throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile(source).getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile(source).getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(CEL_UNPARSER.unparse(optimizedAst)).isEqualTo(source);
 }

 @Test
 public void constantFold_addFoldableFunction_success() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("get_true() == get_true()").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("get_true() == get_true()").getAst();
 ConstantFoldingOptions options =
 ConstantFoldingOptions.newBuilder().addFoldableFunctions("get_true").build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(CEL)
 CelOptimizerFactory.standardCelOptimizerBuilder(runtimeEnv.cel)
 .addAstOptimizers(ConstantFoldingOptimizer.newInstance(options))
 .build();

Expand All@@ -403,7 +442,7 @@ public void constantFold_addFoldableFunction_success() throws Exception {

 @Test
 public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 Cel cel = CelFactory.standardCelBuilder().setResultType(SimpleType.STRING).build();
 Cel cel = runtimeEnv.newCelBuilder().setResultType(SimpleType.STRING).build();
 CelOptimizer optimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
 .addAstOptimizers(ConstantFoldingOptimizer.getInstance())
Expand All@@ -419,10 +458,11 @@ public void constantFold_withExpectedResultTypeSet_success() throws Exception {
 public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNotSet()
 throws Exception {
 Cel cel =
 CelFactory.standardCelBuilder()
 runtimeEnv
 .newCelBuilder()
 .addVar("x", SimpleType.DYN)
 .setStandardMacros(CelStandardMacro.STANDARD_MACROS)
 .setOptions(CelOptions.current().populateMacroCalls(true).build())
 .setOptions(CEL_OPTIONS)
 .build();
 CelOptimizer celOptimizer =
 CelOptimizerFactory.standardCelOptimizerBuilder(cel)
Expand DownExpand Up@@ -492,9 +532,9 @@ public void constantFold_withMacroCallPopulated_comprehensionsAreReplacedWithNot

 @Test
 public void constantFold_astProducesConsistentlyNumberedIds() throws Exception {
 CelAbstractSyntaxTree ast = CEL.compile("[1] + [2] + [3]").getAst();
 CelAbstractSyntaxTree ast = runtimeEnv.cel.compile("[1] + [2] + [3]").getAst();

 CelAbstractSyntaxTree optimizedAst = CEL_OPTIMIZER.optimize(ast);
 CelAbstractSyntaxTree optimizedAst = runtimeEnv.celOptimizer.optimize(ast);

 assertThat(optimizedAst.getExpr().toString())
 .isEqualTo(
Expand All@@ -515,8 +555,13 @@ public void iterationLimitReached_throws() throws Exception {
 sb.append(" + ").append(i);
 } // 0 + 1 + 2 + 3 + ... 200
 Cel cel =
 CelFactory.standardCelBuilder()
 .setOptions(CelOptions.current().maxParseRecursionDepth(200).build())
 runtimeEnv
 .newCelBuilder()
 .setOptions(
 CelOptions.current()
 .enableHeterogeneousNumericComparisons(true)
 .maxParseRecursionDepth(200)
 .build())
 .build();
 CelAbstractSyntaxTree ast = cel.compile(sb.toString()).getAst();
 CelOptimizer optimizer =
Expand Down

7 changes: 6 additions & 1 deletion
runtime/src/main/java/dev/cel/runtime/PartialVars.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -37,7 +37,12 @@ public abstract class PartialVars {

 /** Constructs a new {@code PartialVars} from one or more {@link CelAttributePattern}s. */
 public static PartialVars of(CelAttributePattern... unknownAttributes) {
 return of((unused) -> Optional.empty(), ImmutableList.copyOf(unknownAttributes));
 return of(ImmutableList.copyOf(unknownAttributes));
 }

 /** Constructs a new {@code PartialVars} from a list of {@link CelAttributePattern}s. */
 public static PartialVars of(Iterable<CelAttributePattern> unknownAttributes) {
 return of((unused) -> Optional.empty(), unknownAttributes);
 }

 /**
Expand Down
Loading