Adding the CEL regex extensions#708

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Merged
copybara-service merged 1 commit into from
Jun 5, 2025
Merged

Adding the CEL regex extensions #708

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17 changes: 17 additions & 0 deletions extensions/src/main/java/dev/cel/extensions/BUILD.bazel
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -22,6 +22,7 @@ java_library(
":lists",
":math",
":protos",
":regex",
":sets",
":sets_function",
":strings",
Expand DownExpand Up@@ -241,3 +242,19 @@ java_library(
"@maven//:com_google_guava_guava",
],
)

java_library(
name = "regex",
srcs = ["CelRegexExtensions.java"],
deps = [
"//checker:checker_builder",
"//common:compiler_common",
"//common/types",
"//compiler:compiler_builder",
"//runtime",
"//runtime:function_binding",
"@maven//:com_google_errorprone_error_prone_annotations",
"@maven//:com_google_guava_guava",
"@maven//:com_google_re2j_re2j",
],
)
17 changes: 16 additions & 1 deletion extensions/src/main/java/dev/cel/extensions/CelExtensions.java
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -36,6 +36,7 @@ public final class CelExtensions {
private static final CelBindingsExtensions BINDINGS_EXTENSIONS = new CelBindingsExtensions();
private static final CelEncoderExtensions ENCODER_EXTENSIONS = new CelEncoderExtensions();
private static final CelListsExtensions LISTS_EXTENSIONS_ALL = new CelListsExtensions();
private static final CelRegexExtensions REGEX_EXTENSIONS = new CelRegexExtensions();

/**
* Extended functions for string manipulation.
Expand DownExpand Up@@ -248,6 +249,18 @@ public static CelListsExtensions lists(Set<CelListsExtensions.Function> function
return new CelListsExtensions(functions);
}

/**
* Extended functions for Regular Expressions.
*
* <p>Refer to README.md for available functions.
*
* <p>This will include all functions denoted in {@link CelRegexExtensions.Function}, including
* any future additions.
*/
public static CelRegexExtensions regex() {
return REGEX_EXTENSIONS;
}

/**
* Retrieves all function names used by every extension libraries.
*
Expand All@@ -265,7 +278,9 @@ public static ImmutableSet<String> getAllFunctionNames() {
stream(CelEncoderExtensions.Function.values())
.map(CelEncoderExtensions.Function::getFunction),
stream(CelListsExtensions.Function.values())
.map(CelListsExtensions.Function::getFunction))
.map(CelListsExtensions.Function::getFunction),
stream(CelRegexExtensions.Function.values())
.map(CelRegexExtensions.Function::getFunction))
.collect(toImmutableSet());
}

Expand Down
266 changes: 266 additions & 0 deletions extensions/src/main/java/dev/cel/extensions/CelRegexExtensions.java
View file
Open in desktop
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,266 @@
// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package dev.cel.extensions;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.errorprone.annotations.Immutable;
import com.google.re2j.Matcher;
import com.google.re2j.Pattern;
import com.google.re2j.PatternSyntaxException;
import dev.cel.checker.CelCheckerBuilder;
import dev.cel.common.CelFunctionDecl;
import dev.cel.common.CelOverloadDecl;
import dev.cel.common.types.ListType;
import dev.cel.common.types.MapType;
import dev.cel.common.types.OptionalType;
import dev.cel.common.types.SimpleType;
import dev.cel.compiler.CelCompilerLibrary;
import dev.cel.runtime.CelFunctionBinding;
import dev.cel.runtime.CelRuntimeBuilder;
import dev.cel.runtime.CelRuntimeLibrary;
import java.util.Optional;
import java.util.Set;

/** Internal implementation of CEL regex extensions. */
@Immutable
final class CelRegexExtensions implements CelCompilerLibrary, CelRuntimeLibrary {

private static final String REGEX_REPLACE_FUNCTION = "regex.replace";
private static final String REGEX_CAPTURE_FUNCTION = "regex.capture";
private static final String REGEX_CAPTUREALL_FUNCTION = "regex.captureAll";
private static final String REGEX_CAPTUREALLNAMED_FUNCTION = "regex.captureAllNamed";

enum Function {
REPLACE(
CelFunctionDecl.newFunctionDeclaration(
REGEX_REPLACE_FUNCTION,
CelOverloadDecl.newGlobalOverload(
"regex_replaceAll_string_string_string",
"Replaces all the matched values using the given replace string.",
SimpleType.STRING,
SimpleType.STRING,
SimpleType.STRING,
SimpleType.STRING),
CelOverloadDecl.newGlobalOverload(
"regex_replaceCount_string_string_string_int",
"Replaces the given number of matched values using the given replace string.",
SimpleType.STRING,
SimpleType.STRING,
SimpleType.STRING,
SimpleType.STRING,
SimpleType.INT)),
ImmutableSet.of(
CelFunctionBinding.from(
"regex_replaceAll_string_string_string",
ImmutableList.of(String.class, String.class, String.class),
(args) -> {
String target = (String) args[0];
String pattern = (String) args[1];
String replaceStr = (String) args[2];
return CelRegexExtensions.replace(target, pattern, replaceStr);
}),
CelFunctionBinding.from(
"regex_replaceCount_string_string_string_int",
ImmutableList.of(String.class, String.class, String.class, Long.class),
(args) -> {
String target = (String) args[0];
String pattern = (String) args[1];
String replaceStr = (String) args[2];
long count = (long) args[3];
return CelRegexExtensions.replace(target, pattern, replaceStr, count);
}))),
CAPTURE(
CelFunctionDecl.newFunctionDeclaration(
REGEX_CAPTURE_FUNCTION,
CelOverloadDecl.newGlobalOverload(
"regex_capture_string_string",
"Returns the first substring that matches the regex.",
OptionalType.create(SimpleType.STRING),
SimpleType.STRING,
SimpleType.STRING)),
ImmutableSet.of(
CelFunctionBinding.from(
"regex_capture_string_string",
String.class,
String.class,
CelRegexExtensions::captureFirstMatch))),
CAPTUREALL(
CelFunctionDecl.newFunctionDeclaration(
REGEX_CAPTUREALL_FUNCTION,
CelOverloadDecl.newGlobalOverload(
"regex_captureAll_string_string",
"Returns an arrat of all substrings that match the regex.",
ListType.create(SimpleType.STRING),
SimpleType.STRING,
SimpleType.STRING)),
ImmutableSet.of(
CelFunctionBinding.from(
"regex_captureAll_string_string",
String.class,
String.class,
CelRegexExtensions::captureAllMatches))),
CAPTUREALLNAMED(
CelFunctionDecl.newFunctionDeclaration(
REGEX_CAPTUREALLNAMED_FUNCTION,
CelOverloadDecl.newGlobalOverload(
"regex_captureAllNamed_string_string",
"Returns a map of all named captured groups as <named_group_name, captured_string>."
+ " Ignores the unnamed capture groups.",
MapType.create(SimpleType.STRING, SimpleType.STRING),
SimpleType.STRING,
SimpleType.STRING)),
ImmutableSet.of(
CelFunctionBinding.from(
"regex_captureAllNamed_string_string",
String.class,
String.class,
CelRegexExtensions::captureAllNamedGroups)));

private final CelFunctionDecl functionDecl;
private final ImmutableSet<CelFunctionBinding> functionBindings;

String getFunction() {
return functionDecl.name();
}

Function(CelFunctionDecl functionDecl, ImmutableSet<CelFunctionBinding> functionBindings) {
this.functionDecl = functionDecl;
this.functionBindings = functionBindings;
}
}

private final ImmutableSet<Function> functions;

CelRegexExtensions() {
this.functions = ImmutableSet.copyOf(Function.values());
}

CelRegexExtensions(Set<Function> functions) {
this.functions = ImmutableSet.copyOf(functions);
}

@Override
public void setCheckerOptions(CelCheckerBuilder checkerBuilder) {
functions.forEach(function -> checkerBuilder.addFunctionDeclarations(function.functionDecl));
}

@Override
public void setRuntimeOptions(CelRuntimeBuilder runtimeBuilder) {
functions.forEach(function -> runtimeBuilder.addFunctionBindings(function.functionBindings));
}

private static Pattern compileRegexPattern(String regex) {
try {
return Pattern.compile(regex);
} catch (PatternSyntaxException e) {
throw new IllegalArgumentException("Failed to compile regex: " + regex, e);
}
}

private static String replace(String target, String regex, String replaceStr) {
Pattern pattern = compileRegexPattern(regex);
Matcher matcher = pattern.matcher(target);
return matcher.replaceAll(replaceStr);
}

private static String replace(String target, String regex, String replaceStr, long replaceCount) {
Pattern pattern = compileRegexPattern(regex);

if (replaceCount == 0) {
return target;
}

Matcher matcher = pattern.matcher(target);
StringBuffer sb = new StringBuffer();
int counter = 0;

while (matcher.find()) {
if (replaceCount != -1 && counter >= replaceCount) {
break;
}
matcher.appendReplacement(sb, replaceStr);
counter++;
}
matcher.appendTail(sb);

return sb.toString();
}

private static Optional<String> captureFirstMatch(String target, String regex) {
Pattern pattern = compileRegexPattern(regex);
Matcher matcher = pattern.matcher(target);

if (matcher.find()) {
// If there are capture groups, return the first one.
if (matcher.groupCount() > 0) {
return Optional.ofNullable(matcher.group(1));
} else {
// If there are no capture groups, return the entire match.
return Optional.of(matcher.group(0));
}
}

return Optional.empty();
}

private static ImmutableList<String> captureAllMatches(String target, String regex) {
Pattern pattern = compileRegexPattern(regex);

Matcher matcher = pattern.matcher(target);
ImmutableList.Builder<String> builder = ImmutableList.builder();

while (matcher.find()) {
// If there are capture groups, return all of them. Otherwise, return the entire match.
if (matcher.groupCount() > 0) {
// Add all the capture groups to the result list.
for (int i = 1; i <= matcher.groupCount(); i++) {
String group = matcher.group(i);
if (group != null) {
builder.add(group);
}
}
} else {
builder.add(matcher.group(0));
}
}

return builder.build();
}

private static ImmutableMap<String, String> captureAllNamedGroups(String target, String regex) {
ImmutableMap.Builder<String, String> builder = ImmutableMap.builder();
Pattern pattern = compileRegexPattern(regex);

Set<String> groupNames = pattern.namedGroups().keySet();
if (groupNames.isEmpty()) {
return builder.buildOrThrow();
}

Matcher matcher = pattern.matcher(target);

while (matcher.find()) {

for (String groupName : groupNames) {
String capturedValue = matcher.group(groupName);
if (capturedValue != null) {
builder.put(groupName, capturedValue);
}
}
}
return builder.buildOrThrow();
}
}
6 changes: 5 additions & 1 deletion extensions/src/test/java/dev/cel/extensions/CelExtensionsTest.java
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -178,6 +178,10 @@ public void getAllFunctionNames() {
"base64.decode",
"base64.encode",
"flatten",
"lists.range");
"lists.range",
"regex.replace",
"regex.capture",
"regex.captureAll",
"regex.captureAllNamed");
}
}
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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Adding the CEL regex extensions#708

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

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to your account

 Merged

copybara-service
merged 1 commit into

from

Jun 5, 2025
 Merged


Adding the CEL regex extensions
#708
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17 changes: 17 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -22,6 +22,7 @@ java_library(
 ":lists",
 ":math",
 ":protos",
 ":regex",
 ":sets",
 ":sets_function",
 ":strings",
Expand DownExpand Up@@ -241,3 +242,19 @@ java_library(
 "@maven//:com_google_guava_guava",
 ],
)

java_library(
 name = "regex",
 srcs = ["CelRegexExtensions.java"],
 deps = [
 "//checker:checker_builder",
 "//common:compiler_common",
 "//common/types",
 "//compiler:compiler_builder",
 "//runtime",
 "//runtime:function_binding",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 "@maven//:com_google_re2j_re2j",
 ],
)

17 changes: 16 additions & 1 deletion
extensions/src/main/java/dev/cel/extensions/CelExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -36,6 +36,7 @@ public final class CelExtensions {
 private static final CelBindingsExtensions BINDINGS_EXTENSIONS = new CelBindingsExtensions();
 private static final CelEncoderExtensions ENCODER_EXTENSIONS = new CelEncoderExtensions();
 private static final CelListsExtensions LISTS_EXTENSIONS_ALL = new CelListsExtensions();
 private static final CelRegexExtensions REGEX_EXTENSIONS = new CelRegexExtensions();

 /**
 * Extended functions for string manipulation.
Expand DownExpand Up@@ -248,6 +249,18 @@ public static CelListsExtensions lists(Set<CelListsExtensions.Function> function
 return new CelListsExtensions(functions);
 }

 /**
 * Extended functions for Regular Expressions.
 *
 * <p>Refer to README.md for available functions.
 *
 * <p>This will include all functions denoted in {@link CelRegexExtensions.Function}, including
 * any future additions.
 */
 public static CelRegexExtensions regex() {
 return REGEX_EXTENSIONS;
 }

 /**
 * Retrieves all function names used by every extension libraries.
 *
Expand All@@ -265,7 +278,9 @@ public static ImmutableSet<String> getAllFunctionNames() {
 stream(CelEncoderExtensions.Function.values())
 .map(CelEncoderExtensions.Function::getFunction),
 stream(CelListsExtensions.Function.values())
 .map(CelListsExtensions.Function::getFunction))
 .map(CelListsExtensions.Function::getFunction),
 stream(CelRegexExtensions.Function.values())
 .map(CelRegexExtensions.Function::getFunction))
 .collect(toImmutableSet());
 }

Expand Down

266 changes: 266 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/CelRegexExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,266 @@
// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package dev.cel.extensions;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.errorprone.annotations.Immutable;
import com.google.re2j.Matcher;
import com.google.re2j.Pattern;
import com.google.re2j.PatternSyntaxException;
import dev.cel.checker.CelCheckerBuilder;
import dev.cel.common.CelFunctionDecl;
import dev.cel.common.CelOverloadDecl;
import dev.cel.common.types.ListType;
import dev.cel.common.types.MapType;
import dev.cel.common.types.OptionalType;
import dev.cel.common.types.SimpleType;
import dev.cel.compiler.CelCompilerLibrary;
import dev.cel.runtime.CelFunctionBinding;
import dev.cel.runtime.CelRuntimeBuilder;
import dev.cel.runtime.CelRuntimeLibrary;
import java.util.Optional;
import java.util.Set;

/** Internal implementation of CEL regex extensions. */
@Immutable
final class CelRegexExtensions implements CelCompilerLibrary, CelRuntimeLibrary {

 private static final String REGEX_REPLACE_FUNCTION = "regex.replace";
 private static final String REGEX_CAPTURE_FUNCTION = "regex.capture";
 private static final String REGEX_CAPTUREALL_FUNCTION = "regex.captureAll";
 private static final String REGEX_CAPTUREALLNAMED_FUNCTION = "regex.captureAllNamed";

 enum Function {
 REPLACE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_REPLACE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceAll_string_string_string",
 "Replaces all the matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING),
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceCount_string_string_string_int",
 "Replaces the given number of matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.INT)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_replaceAll_string_string_string",
 ImmutableList.of(String.class, String.class, String.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 return CelRegexExtensions.replace(target, pattern, replaceStr);
 }),
 CelFunctionBinding.from(
 "regex_replaceCount_string_string_string_int",
 ImmutableList.of(String.class, String.class, String.class, Long.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 long count = (long) args[3];
 return CelRegexExtensions.replace(target, pattern, replaceStr, count);
 }))),
 CAPTURE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTURE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_capture_string_string",
 "Returns the first substring that matches the regex.",
 OptionalType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_capture_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureFirstMatch))),
 CAPTUREALL(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALL_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAll_string_string",
 "Returns an arrat of all substrings that match the regex.",
 ListType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAll_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllMatches))),
 CAPTUREALLNAMED(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALLNAMED_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAllNamed_string_string",
 "Returns a map of all named captured groups as <named_group_name, captured_string>."
 + " Ignores the unnamed capture groups.",
 MapType.create(SimpleType.STRING, SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAllNamed_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllNamedGroups)));

 private final CelFunctionDecl functionDecl;
 private final ImmutableSet<CelFunctionBinding> functionBindings;

 String getFunction() {
 return functionDecl.name();
 }

 Function(CelFunctionDecl functionDecl, ImmutableSet<CelFunctionBinding> functionBindings) {
 this.functionDecl = functionDecl;
 this.functionBindings = functionBindings;
 }
 }

 private final ImmutableSet<Function> functions;

 CelRegexExtensions() {
 this.functions = ImmutableSet.copyOf(Function.values());
 }

 CelRegexExtensions(Set<Function> functions) {
 this.functions = ImmutableSet.copyOf(functions);
 }

 @Override
 public void setCheckerOptions(CelCheckerBuilder checkerBuilder) {
 functions.forEach(function -> checkerBuilder.addFunctionDeclarations(function.functionDecl));
 }

 @Override
 public void setRuntimeOptions(CelRuntimeBuilder runtimeBuilder) {
 functions.forEach(function -> runtimeBuilder.addFunctionBindings(function.functionBindings));
 }

 private static Pattern compileRegexPattern(String regex) {
 try {
 return Pattern.compile(regex);
 } catch (PatternSyntaxException e) {
 throw new IllegalArgumentException("Failed to compile regex: " + regex, e);
 }
 }

 private static String replace(String target, String regex, String replaceStr) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);
 return matcher.replaceAll(replaceStr);
 }

 private static String replace(String target, String regex, String replaceStr, long replaceCount) {
 Pattern pattern = compileRegexPattern(regex);

 if (replaceCount == 0) {
 return target;
 }

 Matcher matcher = pattern.matcher(target);
 StringBuffer sb = new StringBuffer();
 int counter = 0;

 while (matcher.find()) {
 if (replaceCount != -1 && counter >= replaceCount) {
 break;
 }
 matcher.appendReplacement(sb, replaceStr);
 counter++;
 }
 matcher.appendTail(sb);

 return sb.toString();
 }

 private static Optional<String> captureFirstMatch(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);

 if (matcher.find()) {
 // If there are capture groups, return the first one.
 if (matcher.groupCount() > 0) {
 return Optional.ofNullable(matcher.group(1));
 } else {
 // If there are no capture groups, return the entire match.
 return Optional.of(matcher.group(0));
 }
 }

 return Optional.empty();
 }

 private static ImmutableList<String> captureAllMatches(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);

 Matcher matcher = pattern.matcher(target);
 ImmutableList.Builder<String> builder = ImmutableList.builder();

 while (matcher.find()) {
 // If there are capture groups, return all of them. Otherwise, return the entire match.
 if (matcher.groupCount() > 0) {
 // Add all the capture groups to the result list.
 for (int i = 1; i <= matcher.groupCount(); i++) {
 String group = matcher.group(i);
 if (group != null) {
 builder.add(group);
 }
 }
 } else {
 builder.add(matcher.group(0));
 }
 }

 return builder.build();
 }

 private static ImmutableMap<String, String> captureAllNamedGroups(String target, String regex) {
 ImmutableMap.Builder<String, String> builder = ImmutableMap.builder();
 Pattern pattern = compileRegexPattern(regex);

 Set<String> groupNames = pattern.namedGroups().keySet();
 if (groupNames.isEmpty()) {
 return builder.buildOrThrow();
 }

 Matcher matcher = pattern.matcher(target);

 while (matcher.find()) {

 for (String groupName : groupNames) {
 String capturedValue = matcher.group(groupName);
 if (capturedValue != null) {
 builder.put(groupName, capturedValue);
 }
 }
 }
 return builder.buildOrThrow();
 }
}

6 changes: 5 additions & 1 deletion
extensions/src/test/java/dev/cel/extensions/CelExtensionsTest.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -178,6 +178,10 @@ public void getAllFunctionNames() {
 "base64.decode",
 "base64.encode",
 "flatten",
 "lists.range");
 "lists.range",
 "regex.replace",
 "regex.capture",
 "regex.captureAll",
 "regex.captureAllNamed");
 }
}
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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Adding the CEL regex extensions#708

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 Merged

copybara-service
merged 1 commit into

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Jun 5, 2025
 Merged


Adding the CEL regex extensions
#708
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17 changes: 17 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -22,6 +22,7 @@ java_library(
 ":lists",
 ":math",
 ":protos",
 ":regex",
 ":sets",
 ":sets_function",
 ":strings",
Expand DownExpand Up@@ -241,3 +242,19 @@ java_library(
 "@maven//:com_google_guava_guava",
 ],
)

java_library(
 name = "regex",
 srcs = ["CelRegexExtensions.java"],
 deps = [
 "//checker:checker_builder",
 "//common:compiler_common",
 "//common/types",
 "//compiler:compiler_builder",
 "//runtime",
 "//runtime:function_binding",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 "@maven//:com_google_re2j_re2j",
 ],
)

17 changes: 16 additions & 1 deletion
extensions/src/main/java/dev/cel/extensions/CelExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -36,6 +36,7 @@ public final class CelExtensions {
 private static final CelBindingsExtensions BINDINGS_EXTENSIONS = new CelBindingsExtensions();
 private static final CelEncoderExtensions ENCODER_EXTENSIONS = new CelEncoderExtensions();
 private static final CelListsExtensions LISTS_EXTENSIONS_ALL = new CelListsExtensions();
 private static final CelRegexExtensions REGEX_EXTENSIONS = new CelRegexExtensions();

 /**
 * Extended functions for string manipulation.
Expand DownExpand Up@@ -248,6 +249,18 @@ public static CelListsExtensions lists(Set<CelListsExtensions.Function> function
 return new CelListsExtensions(functions);
 }

 /**
 * Extended functions for Regular Expressions.
 *
 * <p>Refer to README.md for available functions.
 *
 * <p>This will include all functions denoted in {@link CelRegexExtensions.Function}, including
 * any future additions.
 */
 public static CelRegexExtensions regex() {
 return REGEX_EXTENSIONS;
 }

 /**
 * Retrieves all function names used by every extension libraries.
 *
Expand All@@ -265,7 +278,9 @@ public static ImmutableSet<String> getAllFunctionNames() {
 stream(CelEncoderExtensions.Function.values())
 .map(CelEncoderExtensions.Function::getFunction),
 stream(CelListsExtensions.Function.values())
 .map(CelListsExtensions.Function::getFunction))
 .map(CelListsExtensions.Function::getFunction),
 stream(CelRegexExtensions.Function.values())
 .map(CelRegexExtensions.Function::getFunction))
 .collect(toImmutableSet());
 }

Expand Down

266 changes: 266 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/CelRegexExtensions.java

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Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,266 @@
// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package dev.cel.extensions;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.errorprone.annotations.Immutable;
import com.google.re2j.Matcher;
import com.google.re2j.Pattern;
import com.google.re2j.PatternSyntaxException;
import dev.cel.checker.CelCheckerBuilder;
import dev.cel.common.CelFunctionDecl;
import dev.cel.common.CelOverloadDecl;
import dev.cel.common.types.ListType;
import dev.cel.common.types.MapType;
import dev.cel.common.types.OptionalType;
import dev.cel.common.types.SimpleType;
import dev.cel.compiler.CelCompilerLibrary;
import dev.cel.runtime.CelFunctionBinding;
import dev.cel.runtime.CelRuntimeBuilder;
import dev.cel.runtime.CelRuntimeLibrary;
import java.util.Optional;
import java.util.Set;

/** Internal implementation of CEL regex extensions. */
@Immutable
final class CelRegexExtensions implements CelCompilerLibrary, CelRuntimeLibrary {

 private static final String REGEX_REPLACE_FUNCTION = "regex.replace";
 private static final String REGEX_CAPTURE_FUNCTION = "regex.capture";
 private static final String REGEX_CAPTUREALL_FUNCTION = "regex.captureAll";
 private static final String REGEX_CAPTUREALLNAMED_FUNCTION = "regex.captureAllNamed";

 enum Function {
 REPLACE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_REPLACE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceAll_string_string_string",
 "Replaces all the matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING),
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceCount_string_string_string_int",
 "Replaces the given number of matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.INT)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_replaceAll_string_string_string",
 ImmutableList.of(String.class, String.class, String.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 return CelRegexExtensions.replace(target, pattern, replaceStr);
 }),
 CelFunctionBinding.from(
 "regex_replaceCount_string_string_string_int",
 ImmutableList.of(String.class, String.class, String.class, Long.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 long count = (long) args[3];
 return CelRegexExtensions.replace(target, pattern, replaceStr, count);
 }))),
 CAPTURE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTURE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_capture_string_string",
 "Returns the first substring that matches the regex.",
 OptionalType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_capture_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureFirstMatch))),
 CAPTUREALL(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALL_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAll_string_string",
 "Returns an arrat of all substrings that match the regex.",
 ListType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAll_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllMatches))),
 CAPTUREALLNAMED(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALLNAMED_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAllNamed_string_string",
 "Returns a map of all named captured groups as <named_group_name, captured_string>."
 + " Ignores the unnamed capture groups.",
 MapType.create(SimpleType.STRING, SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAllNamed_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllNamedGroups)));

 private final CelFunctionDecl functionDecl;
 private final ImmutableSet<CelFunctionBinding> functionBindings;

 String getFunction() {
 return functionDecl.name();
 }

 Function(CelFunctionDecl functionDecl, ImmutableSet<CelFunctionBinding> functionBindings) {
 this.functionDecl = functionDecl;
 this.functionBindings = functionBindings;
 }
 }

 private final ImmutableSet<Function> functions;

 CelRegexExtensions() {
 this.functions = ImmutableSet.copyOf(Function.values());
 }

 CelRegexExtensions(Set<Function> functions) {
 this.functions = ImmutableSet.copyOf(functions);
 }

 @Override
 public void setCheckerOptions(CelCheckerBuilder checkerBuilder) {
 functions.forEach(function -> checkerBuilder.addFunctionDeclarations(function.functionDecl));
 }

 @Override
 public void setRuntimeOptions(CelRuntimeBuilder runtimeBuilder) {
 functions.forEach(function -> runtimeBuilder.addFunctionBindings(function.functionBindings));
 }

 private static Pattern compileRegexPattern(String regex) {
 try {
 return Pattern.compile(regex);
 } catch (PatternSyntaxException e) {
 throw new IllegalArgumentException("Failed to compile regex: " + regex, e);
 }
 }

 private static String replace(String target, String regex, String replaceStr) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);
 return matcher.replaceAll(replaceStr);
 }

 private static String replace(String target, String regex, String replaceStr, long replaceCount) {
 Pattern pattern = compileRegexPattern(regex);

 if (replaceCount == 0) {
 return target;
 }

 Matcher matcher = pattern.matcher(target);
 StringBuffer sb = new StringBuffer();
 int counter = 0;

 while (matcher.find()) {
 if (replaceCount != -1 && counter >= replaceCount) {
 break;
 }
 matcher.appendReplacement(sb, replaceStr);
 counter++;
 }
 matcher.appendTail(sb);

 return sb.toString();
 }

 private static Optional<String> captureFirstMatch(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);

 if (matcher.find()) {
 // If there are capture groups, return the first one.
 if (matcher.groupCount() > 0) {
 return Optional.ofNullable(matcher.group(1));
 } else {
 // If there are no capture groups, return the entire match.
 return Optional.of(matcher.group(0));
 }
 }

 return Optional.empty();
 }

 private static ImmutableList<String> captureAllMatches(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);

 Matcher matcher = pattern.matcher(target);
 ImmutableList.Builder<String> builder = ImmutableList.builder();

 while (matcher.find()) {
 // If there are capture groups, return all of them. Otherwise, return the entire match.
 if (matcher.groupCount() > 0) {
 // Add all the capture groups to the result list.
 for (int i = 1; i <= matcher.groupCount(); i++) {
 String group = matcher.group(i);
 if (group != null) {
 builder.add(group);
 }
 }
 } else {
 builder.add(matcher.group(0));
 }
 }

 return builder.build();
 }

 private static ImmutableMap<String, String> captureAllNamedGroups(String target, String regex) {
 ImmutableMap.Builder<String, String> builder = ImmutableMap.builder();
 Pattern pattern = compileRegexPattern(regex);

 Set<String> groupNames = pattern.namedGroups().keySet();
 if (groupNames.isEmpty()) {
 return builder.buildOrThrow();
 }

 Matcher matcher = pattern.matcher(target);

 while (matcher.find()) {

 for (String groupName : groupNames) {
 String capturedValue = matcher.group(groupName);
 if (capturedValue != null) {
 builder.put(groupName, capturedValue);
 }
 }
 }
 return builder.buildOrThrow();
 }
}

6 changes: 5 additions & 1 deletion
extensions/src/test/java/dev/cel/extensions/CelExtensionsTest.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -178,6 +178,10 @@ public void getAllFunctionNames() {
 "base64.decode",
 "base64.encode",
 "flatten",
 "lists.range");
 "lists.range",
 "regex.replace",
 "regex.capture",
 "regex.captureAll",
 "regex.captureAllNamed");
 }
}
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
Adding the CEL regex extensions#708

New issue

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

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
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

Jun 5, 2025
 Merged


Adding the CEL regex extensions
#708
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Hide file tree
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17 changes: 17 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -22,6 +22,7 @@ java_library(
 ":lists",
 ":math",
 ":protos",
 ":regex",
 ":sets",
 ":sets_function",
 ":strings",
Expand DownExpand Up@@ -241,3 +242,19 @@ java_library(
 "@maven//:com_google_guava_guava",
 ],
)

java_library(
 name = "regex",
 srcs = ["CelRegexExtensions.java"],
 deps = [
 "//checker:checker_builder",
 "//common:compiler_common",
 "//common/types",
 "//compiler:compiler_builder",
 "//runtime",
 "//runtime:function_binding",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 "@maven//:com_google_re2j_re2j",
 ],
)

17 changes: 16 additions & 1 deletion
extensions/src/main/java/dev/cel/extensions/CelExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -36,6 +36,7 @@ public final class CelExtensions {
 private static final CelBindingsExtensions BINDINGS_EXTENSIONS = new CelBindingsExtensions();
 private static final CelEncoderExtensions ENCODER_EXTENSIONS = new CelEncoderExtensions();
 private static final CelListsExtensions LISTS_EXTENSIONS_ALL = new CelListsExtensions();
 private static final CelRegexExtensions REGEX_EXTENSIONS = new CelRegexExtensions();

 /**
 * Extended functions for string manipulation.
Expand DownExpand Up@@ -248,6 +249,18 @@ public static CelListsExtensions lists(Set<CelListsExtensions.Function> function
 return new CelListsExtensions(functions);
 }

 /**
 * Extended functions for Regular Expressions.
 *
 * <p>Refer to README.md for available functions.
 *
 * <p>This will include all functions denoted in {@link CelRegexExtensions.Function}, including
 * any future additions.
 */
 public static CelRegexExtensions regex() {
 return REGEX_EXTENSIONS;
 }

 /**
 * Retrieves all function names used by every extension libraries.
 *
Expand All@@ -265,7 +278,9 @@ public static ImmutableSet<String> getAllFunctionNames() {
 stream(CelEncoderExtensions.Function.values())
 .map(CelEncoderExtensions.Function::getFunction),
 stream(CelListsExtensions.Function.values())
 .map(CelListsExtensions.Function::getFunction))
 .map(CelListsExtensions.Function::getFunction),
 stream(CelRegexExtensions.Function.values())
 .map(CelRegexExtensions.Function::getFunction))
 .collect(toImmutableSet());
 }

Expand Down

266 changes: 266 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/CelRegexExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,266 @@
// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package dev.cel.extensions;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.errorprone.annotations.Immutable;
import com.google.re2j.Matcher;
import com.google.re2j.Pattern;
import com.google.re2j.PatternSyntaxException;
import dev.cel.checker.CelCheckerBuilder;
import dev.cel.common.CelFunctionDecl;
import dev.cel.common.CelOverloadDecl;
import dev.cel.common.types.ListType;
import dev.cel.common.types.MapType;
import dev.cel.common.types.OptionalType;
import dev.cel.common.types.SimpleType;
import dev.cel.compiler.CelCompilerLibrary;
import dev.cel.runtime.CelFunctionBinding;
import dev.cel.runtime.CelRuntimeBuilder;
import dev.cel.runtime.CelRuntimeLibrary;
import java.util.Optional;
import java.util.Set;

/** Internal implementation of CEL regex extensions. */
@Immutable
final class CelRegexExtensions implements CelCompilerLibrary, CelRuntimeLibrary {

 private static final String REGEX_REPLACE_FUNCTION = "regex.replace";
 private static final String REGEX_CAPTURE_FUNCTION = "regex.capture";
 private static final String REGEX_CAPTUREALL_FUNCTION = "regex.captureAll";
 private static final String REGEX_CAPTUREALLNAMED_FUNCTION = "regex.captureAllNamed";

 enum Function {
 REPLACE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_REPLACE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceAll_string_string_string",
 "Replaces all the matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING),
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceCount_string_string_string_int",
 "Replaces the given number of matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.INT)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_replaceAll_string_string_string",
 ImmutableList.of(String.class, String.class, String.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 return CelRegexExtensions.replace(target, pattern, replaceStr);
 }),
 CelFunctionBinding.from(
 "regex_replaceCount_string_string_string_int",
 ImmutableList.of(String.class, String.class, String.class, Long.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 long count = (long) args[3];
 return CelRegexExtensions.replace(target, pattern, replaceStr, count);
 }))),
 CAPTURE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTURE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_capture_string_string",
 "Returns the first substring that matches the regex.",
 OptionalType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_capture_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureFirstMatch))),
 CAPTUREALL(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALL_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAll_string_string",
 "Returns an arrat of all substrings that match the regex.",
 ListType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAll_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllMatches))),
 CAPTUREALLNAMED(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALLNAMED_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAllNamed_string_string",
 "Returns a map of all named captured groups as <named_group_name, captured_string>."
 + " Ignores the unnamed capture groups.",
 MapType.create(SimpleType.STRING, SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAllNamed_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllNamedGroups)));

 private final CelFunctionDecl functionDecl;
 private final ImmutableSet<CelFunctionBinding> functionBindings;

 String getFunction() {
 return functionDecl.name();
 }

 Function(CelFunctionDecl functionDecl, ImmutableSet<CelFunctionBinding> functionBindings) {
 this.functionDecl = functionDecl;
 this.functionBindings = functionBindings;
 }
 }

 private final ImmutableSet<Function> functions;

 CelRegexExtensions() {
 this.functions = ImmutableSet.copyOf(Function.values());
 }

 CelRegexExtensions(Set<Function> functions) {
 this.functions = ImmutableSet.copyOf(functions);
 }

 @Override
 public void setCheckerOptions(CelCheckerBuilder checkerBuilder) {
 functions.forEach(function -> checkerBuilder.addFunctionDeclarations(function.functionDecl));
 }

 @Override
 public void setRuntimeOptions(CelRuntimeBuilder runtimeBuilder) {
 functions.forEach(function -> runtimeBuilder.addFunctionBindings(function.functionBindings));
 }

 private static Pattern compileRegexPattern(String regex) {
 try {
 return Pattern.compile(regex);
 } catch (PatternSyntaxException e) {
 throw new IllegalArgumentException("Failed to compile regex: " + regex, e);
 }
 }

 private static String replace(String target, String regex, String replaceStr) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);
 return matcher.replaceAll(replaceStr);
 }

 private static String replace(String target, String regex, String replaceStr, long replaceCount) {
 Pattern pattern = compileRegexPattern(regex);

 if (replaceCount == 0) {
 return target;
 }

 Matcher matcher = pattern.matcher(target);
 StringBuffer sb = new StringBuffer();
 int counter = 0;

 while (matcher.find()) {
 if (replaceCount != -1 && counter >= replaceCount) {
 break;
 }
 matcher.appendReplacement(sb, replaceStr);
 counter++;
 }
 matcher.appendTail(sb);

 return sb.toString();
 }

 private static Optional<String> captureFirstMatch(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);

 if (matcher.find()) {
 // If there are capture groups, return the first one.
 if (matcher.groupCount() > 0) {
 return Optional.ofNullable(matcher.group(1));
 } else {
 // If there are no capture groups, return the entire match.
 return Optional.of(matcher.group(0));
 }
 }

 return Optional.empty();
 }

 private static ImmutableList<String> captureAllMatches(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);

 Matcher matcher = pattern.matcher(target);
 ImmutableList.Builder<String> builder = ImmutableList.builder();

 while (matcher.find()) {
 // If there are capture groups, return all of them. Otherwise, return the entire match.
 if (matcher.groupCount() > 0) {
 // Add all the capture groups to the result list.
 for (int i = 1; i <= matcher.groupCount(); i++) {
 String group = matcher.group(i);
 if (group != null) {
 builder.add(group);
 }
 }
 } else {
 builder.add(matcher.group(0));
 }
 }

 return builder.build();
 }

 private static ImmutableMap<String, String> captureAllNamedGroups(String target, String regex) {
 ImmutableMap.Builder<String, String> builder = ImmutableMap.builder();
 Pattern pattern = compileRegexPattern(regex);

 Set<String> groupNames = pattern.namedGroups().keySet();
 if (groupNames.isEmpty()) {
 return builder.buildOrThrow();
 }

 Matcher matcher = pattern.matcher(target);

 while (matcher.find()) {

 for (String groupName : groupNames) {
 String capturedValue = matcher.group(groupName);
 if (capturedValue != null) {
 builder.put(groupName, capturedValue);
 }
 }
 }
 return builder.buildOrThrow();
 }
}

6 changes: 5 additions & 1 deletion
extensions/src/test/java/dev/cel/extensions/CelExtensionsTest.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -178,6 +178,10 @@ public void getAllFunctionNames() {
 "base64.decode",
 "base64.encode",
 "flatten",
 "lists.range");
 "lists.range",
 "regex.replace",
 "regex.capture",
 "regex.captureAll",
 "regex.captureAllNamed");
 }
}
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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Adding the CEL regex extensions#708

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 Merged

copybara-service
merged 1 commit into

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Jun 5, 2025
 Merged


Adding the CEL regex extensions
#708
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17 changes: 17 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -22,6 +22,7 @@ java_library(
 ":lists",
 ":math",
 ":protos",
 ":regex",
 ":sets",
 ":sets_function",
 ":strings",
Expand DownExpand Up@@ -241,3 +242,19 @@ java_library(
 "@maven//:com_google_guava_guava",
 ],
)

java_library(
 name = "regex",
 srcs = ["CelRegexExtensions.java"],
 deps = [
 "//checker:checker_builder",
 "//common:compiler_common",
 "//common/types",
 "//compiler:compiler_builder",
 "//runtime",
 "//runtime:function_binding",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 "@maven//:com_google_re2j_re2j",
 ],
)

17 changes: 16 additions & 1 deletion
extensions/src/main/java/dev/cel/extensions/CelExtensions.java

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -36,6 +36,7 @@ public final class CelExtensions {
 private static final CelBindingsExtensions BINDINGS_EXTENSIONS = new CelBindingsExtensions();
 private static final CelEncoderExtensions ENCODER_EXTENSIONS = new CelEncoderExtensions();
 private static final CelListsExtensions LISTS_EXTENSIONS_ALL = new CelListsExtensions();
 private static final CelRegexExtensions REGEX_EXTENSIONS = new CelRegexExtensions();

 /**
 * Extended functions for string manipulation.
Expand DownExpand Up@@ -248,6 +249,18 @@ public static CelListsExtensions lists(Set<CelListsExtensions.Function> function
 return new CelListsExtensions(functions);
 }

 /**
 * Extended functions for Regular Expressions.
 *
 * <p>Refer to README.md for available functions.
 *
 * <p>This will include all functions denoted in {@link CelRegexExtensions.Function}, including
 * any future additions.
 */
 public static CelRegexExtensions regex() {
 return REGEX_EXTENSIONS;
 }

 /**
 * Retrieves all function names used by every extension libraries.
 *
Expand All@@ -265,7 +278,9 @@ public static ImmutableSet<String> getAllFunctionNames() {
 stream(CelEncoderExtensions.Function.values())
 .map(CelEncoderExtensions.Function::getFunction),
 stream(CelListsExtensions.Function.values())
 .map(CelListsExtensions.Function::getFunction))
 .map(CelListsExtensions.Function::getFunction),
 stream(CelRegexExtensions.Function.values())
 .map(CelRegexExtensions.Function::getFunction))
 .collect(toImmutableSet());
 }

Expand Down

266 changes: 266 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/CelRegexExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,266 @@
// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package dev.cel.extensions;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.errorprone.annotations.Immutable;
import com.google.re2j.Matcher;
import com.google.re2j.Pattern;
import com.google.re2j.PatternSyntaxException;
import dev.cel.checker.CelCheckerBuilder;
import dev.cel.common.CelFunctionDecl;
import dev.cel.common.CelOverloadDecl;
import dev.cel.common.types.ListType;
import dev.cel.common.types.MapType;
import dev.cel.common.types.OptionalType;
import dev.cel.common.types.SimpleType;
import dev.cel.compiler.CelCompilerLibrary;
import dev.cel.runtime.CelFunctionBinding;
import dev.cel.runtime.CelRuntimeBuilder;
import dev.cel.runtime.CelRuntimeLibrary;
import java.util.Optional;
import java.util.Set;

/** Internal implementation of CEL regex extensions. */
@Immutable
final class CelRegexExtensions implements CelCompilerLibrary, CelRuntimeLibrary {

 private static final String REGEX_REPLACE_FUNCTION = "regex.replace";
 private static final String REGEX_CAPTURE_FUNCTION = "regex.capture";
 private static final String REGEX_CAPTUREALL_FUNCTION = "regex.captureAll";
 private static final String REGEX_CAPTUREALLNAMED_FUNCTION = "regex.captureAllNamed";

 enum Function {
 REPLACE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_REPLACE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceAll_string_string_string",
 "Replaces all the matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING),
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceCount_string_string_string_int",
 "Replaces the given number of matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.INT)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_replaceAll_string_string_string",
 ImmutableList.of(String.class, String.class, String.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 return CelRegexExtensions.replace(target, pattern, replaceStr);
 }),
 CelFunctionBinding.from(
 "regex_replaceCount_string_string_string_int",
 ImmutableList.of(String.class, String.class, String.class, Long.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 long count = (long) args[3];
 return CelRegexExtensions.replace(target, pattern, replaceStr, count);
 }))),
 CAPTURE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTURE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_capture_string_string",
 "Returns the first substring that matches the regex.",
 OptionalType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_capture_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureFirstMatch))),
 CAPTUREALL(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALL_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAll_string_string",
 "Returns an arrat of all substrings that match the regex.",
 ListType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAll_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllMatches))),
 CAPTUREALLNAMED(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALLNAMED_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAllNamed_string_string",
 "Returns a map of all named captured groups as <named_group_name, captured_string>."
 + " Ignores the unnamed capture groups.",
 MapType.create(SimpleType.STRING, SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAllNamed_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllNamedGroups)));

 private final CelFunctionDecl functionDecl;
 private final ImmutableSet<CelFunctionBinding> functionBindings;

 String getFunction() {
 return functionDecl.name();
 }

 Function(CelFunctionDecl functionDecl, ImmutableSet<CelFunctionBinding> functionBindings) {
 this.functionDecl = functionDecl;
 this.functionBindings = functionBindings;
 }
 }

 private final ImmutableSet<Function> functions;

 CelRegexExtensions() {
 this.functions = ImmutableSet.copyOf(Function.values());
 }

 CelRegexExtensions(Set<Function> functions) {
 this.functions = ImmutableSet.copyOf(functions);
 }

 @Override
 public void setCheckerOptions(CelCheckerBuilder checkerBuilder) {
 functions.forEach(function -> checkerBuilder.addFunctionDeclarations(function.functionDecl));
 }

 @Override
 public void setRuntimeOptions(CelRuntimeBuilder runtimeBuilder) {
 functions.forEach(function -> runtimeBuilder.addFunctionBindings(function.functionBindings));
 }

 private static Pattern compileRegexPattern(String regex) {
 try {
 return Pattern.compile(regex);
 } catch (PatternSyntaxException e) {
 throw new IllegalArgumentException("Failed to compile regex: " + regex, e);
 }
 }

 private static String replace(String target, String regex, String replaceStr) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);
 return matcher.replaceAll(replaceStr);
 }

 private static String replace(String target, String regex, String replaceStr, long replaceCount) {
 Pattern pattern = compileRegexPattern(regex);

 if (replaceCount == 0) {
 return target;
 }

 Matcher matcher = pattern.matcher(target);
 StringBuffer sb = new StringBuffer();
 int counter = 0;

 while (matcher.find()) {
 if (replaceCount != -1 && counter >= replaceCount) {
 break;
 }
 matcher.appendReplacement(sb, replaceStr);
 counter++;
 }
 matcher.appendTail(sb);

 return sb.toString();
 }

 private static Optional<String> captureFirstMatch(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);

 if (matcher.find()) {
 // If there are capture groups, return the first one.
 if (matcher.groupCount() > 0) {
 return Optional.ofNullable(matcher.group(1));
 } else {
 // If there are no capture groups, return the entire match.
 return Optional.of(matcher.group(0));
 }
 }

 return Optional.empty();
 }

 private static ImmutableList<String> captureAllMatches(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);

 Matcher matcher = pattern.matcher(target);
 ImmutableList.Builder<String> builder = ImmutableList.builder();

 while (matcher.find()) {
 // If there are capture groups, return all of them. Otherwise, return the entire match.
 if (matcher.groupCount() > 0) {
 // Add all the capture groups to the result list.
 for (int i = 1; i <= matcher.groupCount(); i++) {
 String group = matcher.group(i);
 if (group != null) {
 builder.add(group);
 }
 }
 } else {
 builder.add(matcher.group(0));
 }
 }

 return builder.build();
 }

 private static ImmutableMap<String, String> captureAllNamedGroups(String target, String regex) {
 ImmutableMap.Builder<String, String> builder = ImmutableMap.builder();
 Pattern pattern = compileRegexPattern(regex);

 Set<String> groupNames = pattern.namedGroups().keySet();
 if (groupNames.isEmpty()) {
 return builder.buildOrThrow();
 }

 Matcher matcher = pattern.matcher(target);

 while (matcher.find()) {

 for (String groupName : groupNames) {
 String capturedValue = matcher.group(groupName);
 if (capturedValue != null) {
 builder.put(groupName, capturedValue);
 }
 }
 }
 return builder.buildOrThrow();
 }
}

6 changes: 5 additions & 1 deletion
extensions/src/test/java/dev/cel/extensions/CelExtensionsTest.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -178,6 +178,10 @@ public void getAllFunctionNames() {
 "base64.decode",
 "base64.encode",
 "flatten",
 "lists.range");
 "lists.range",
 "regex.replace",
 "regex.capture",
 "regex.captureAll",
 "regex.captureAllNamed");
 }
}
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
Adding the CEL regex extensions#708

New issue

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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By clicking “Sign up for GitHub”, you agree to our terms of service and
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

Jun 5, 2025
 Merged


Adding the CEL regex extensions
#708
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17 changes: 17 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -22,6 +22,7 @@ java_library(
 ":lists",
 ":math",
 ":protos",
 ":regex",
 ":sets",
 ":sets_function",
 ":strings",
Expand DownExpand Up@@ -241,3 +242,19 @@ java_library(
 "@maven//:com_google_guava_guava",
 ],
)

java_library(
 name = "regex",
 srcs = ["CelRegexExtensions.java"],
 deps = [
 "//checker:checker_builder",
 "//common:compiler_common",
 "//common/types",
 "//compiler:compiler_builder",
 "//runtime",
 "//runtime:function_binding",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 "@maven//:com_google_re2j_re2j",
 ],
)

17 changes: 16 additions & 1 deletion
extensions/src/main/java/dev/cel/extensions/CelExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -36,6 +36,7 @@ public final class CelExtensions {
 private static final CelBindingsExtensions BINDINGS_EXTENSIONS = new CelBindingsExtensions();
 private static final CelEncoderExtensions ENCODER_EXTENSIONS = new CelEncoderExtensions();
 private static final CelListsExtensions LISTS_EXTENSIONS_ALL = new CelListsExtensions();
 private static final CelRegexExtensions REGEX_EXTENSIONS = new CelRegexExtensions();

 /**
 * Extended functions for string manipulation.
Expand DownExpand Up@@ -248,6 +249,18 @@ public static CelListsExtensions lists(Set<CelListsExtensions.Function> function
 return new CelListsExtensions(functions);
 }

 /**
 * Extended functions for Regular Expressions.
 *
 * <p>Refer to README.md for available functions.
 *
 * <p>This will include all functions denoted in {@link CelRegexExtensions.Function}, including
 * any future additions.
 */
 public static CelRegexExtensions regex() {
 return REGEX_EXTENSIONS;
 }

 /**
 * Retrieves all function names used by every extension libraries.
 *
Expand All@@ -265,7 +278,9 @@ public static ImmutableSet<String> getAllFunctionNames() {
 stream(CelEncoderExtensions.Function.values())
 .map(CelEncoderExtensions.Function::getFunction),
 stream(CelListsExtensions.Function.values())
 .map(CelListsExtensions.Function::getFunction))
 .map(CelListsExtensions.Function::getFunction),
 stream(CelRegexExtensions.Function.values())
 .map(CelRegexExtensions.Function::getFunction))
 .collect(toImmutableSet());
 }

Expand Down

266 changes: 266 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/CelRegexExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,266 @@
// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package dev.cel.extensions;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.errorprone.annotations.Immutable;
import com.google.re2j.Matcher;
import com.google.re2j.Pattern;
import com.google.re2j.PatternSyntaxException;
import dev.cel.checker.CelCheckerBuilder;
import dev.cel.common.CelFunctionDecl;
import dev.cel.common.CelOverloadDecl;
import dev.cel.common.types.ListType;
import dev.cel.common.types.MapType;
import dev.cel.common.types.OptionalType;
import dev.cel.common.types.SimpleType;
import dev.cel.compiler.CelCompilerLibrary;
import dev.cel.runtime.CelFunctionBinding;
import dev.cel.runtime.CelRuntimeBuilder;
import dev.cel.runtime.CelRuntimeLibrary;
import java.util.Optional;
import java.util.Set;

/** Internal implementation of CEL regex extensions. */
@Immutable
final class CelRegexExtensions implements CelCompilerLibrary, CelRuntimeLibrary {

 private static final String REGEX_REPLACE_FUNCTION = "regex.replace";
 private static final String REGEX_CAPTURE_FUNCTION = "regex.capture";
 private static final String REGEX_CAPTUREALL_FUNCTION = "regex.captureAll";
 private static final String REGEX_CAPTUREALLNAMED_FUNCTION = "regex.captureAllNamed";

 enum Function {
 REPLACE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_REPLACE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceAll_string_string_string",
 "Replaces all the matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING),
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceCount_string_string_string_int",
 "Replaces the given number of matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.INT)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_replaceAll_string_string_string",
 ImmutableList.of(String.class, String.class, String.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 return CelRegexExtensions.replace(target, pattern, replaceStr);
 }),
 CelFunctionBinding.from(
 "regex_replaceCount_string_string_string_int",
 ImmutableList.of(String.class, String.class, String.class, Long.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 long count = (long) args[3];
 return CelRegexExtensions.replace(target, pattern, replaceStr, count);
 }))),
 CAPTURE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTURE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_capture_string_string",
 "Returns the first substring that matches the regex.",
 OptionalType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_capture_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureFirstMatch))),
 CAPTUREALL(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALL_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAll_string_string",
 "Returns an arrat of all substrings that match the regex.",
 ListType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAll_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllMatches))),
 CAPTUREALLNAMED(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALLNAMED_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAllNamed_string_string",
 "Returns a map of all named captured groups as <named_group_name, captured_string>."
 + " Ignores the unnamed capture groups.",
 MapType.create(SimpleType.STRING, SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAllNamed_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllNamedGroups)));

 private final CelFunctionDecl functionDecl;
 private final ImmutableSet<CelFunctionBinding> functionBindings;

 String getFunction() {
 return functionDecl.name();
 }

 Function(CelFunctionDecl functionDecl, ImmutableSet<CelFunctionBinding> functionBindings) {
 this.functionDecl = functionDecl;
 this.functionBindings = functionBindings;
 }
 }

 private final ImmutableSet<Function> functions;

 CelRegexExtensions() {
 this.functions = ImmutableSet.copyOf(Function.values());
 }

 CelRegexExtensions(Set<Function> functions) {
 this.functions = ImmutableSet.copyOf(functions);
 }

 @Override
 public void setCheckerOptions(CelCheckerBuilder checkerBuilder) {
 functions.forEach(function -> checkerBuilder.addFunctionDeclarations(function.functionDecl));
 }

 @Override
 public void setRuntimeOptions(CelRuntimeBuilder runtimeBuilder) {
 functions.forEach(function -> runtimeBuilder.addFunctionBindings(function.functionBindings));
 }

 private static Pattern compileRegexPattern(String regex) {
 try {
 return Pattern.compile(regex);
 } catch (PatternSyntaxException e) {
 throw new IllegalArgumentException("Failed to compile regex: " + regex, e);
 }
 }

 private static String replace(String target, String regex, String replaceStr) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);
 return matcher.replaceAll(replaceStr);
 }

 private static String replace(String target, String regex, String replaceStr, long replaceCount) {
 Pattern pattern = compileRegexPattern(regex);

 if (replaceCount == 0) {
 return target;
 }

 Matcher matcher = pattern.matcher(target);
 StringBuffer sb = new StringBuffer();
 int counter = 0;

 while (matcher.find()) {
 if (replaceCount != -1 && counter >= replaceCount) {
 break;
 }
 matcher.appendReplacement(sb, replaceStr);
 counter++;
 }
 matcher.appendTail(sb);

 return sb.toString();
 }

 private static Optional<String> captureFirstMatch(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);

 if (matcher.find()) {
 // If there are capture groups, return the first one.
 if (matcher.groupCount() > 0) {
 return Optional.ofNullable(matcher.group(1));
 } else {
 // If there are no capture groups, return the entire match.
 return Optional.of(matcher.group(0));
 }
 }

 return Optional.empty();
 }

 private static ImmutableList<String> captureAllMatches(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);

 Matcher matcher = pattern.matcher(target);
 ImmutableList.Builder<String> builder = ImmutableList.builder();

 while (matcher.find()) {
 // If there are capture groups, return all of them. Otherwise, return the entire match.
 if (matcher.groupCount() > 0) {
 // Add all the capture groups to the result list.
 for (int i = 1; i <= matcher.groupCount(); i++) {
 String group = matcher.group(i);
 if (group != null) {
 builder.add(group);
 }
 }
 } else {
 builder.add(matcher.group(0));
 }
 }

 return builder.build();
 }

 private static ImmutableMap<String, String> captureAllNamedGroups(String target, String regex) {
 ImmutableMap.Builder<String, String> builder = ImmutableMap.builder();
 Pattern pattern = compileRegexPattern(regex);

 Set<String> groupNames = pattern.namedGroups().keySet();
 if (groupNames.isEmpty()) {
 return builder.buildOrThrow();
 }

 Matcher matcher = pattern.matcher(target);

 while (matcher.find()) {

 for (String groupName : groupNames) {
 String capturedValue = matcher.group(groupName);
 if (capturedValue != null) {
 builder.put(groupName, capturedValue);
 }
 }
 }
 return builder.buildOrThrow();
 }
}

6 changes: 5 additions & 1 deletion
extensions/src/test/java/dev/cel/extensions/CelExtensionsTest.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -178,6 +178,10 @@ public void getAllFunctionNames() {
 "base64.decode",
 "base64.encode",
 "flatten",
 "lists.range");
 "lists.range",
 "regex.replace",
 "regex.capture",
 "regex.captureAll",
 "regex.captureAllNamed");
 }
}
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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Adding the CEL regex extensions#708

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 Merged

copybara-service
merged 1 commit into

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Jun 5, 2025
 Merged


Adding the CEL regex extensions
#708
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17 changes: 17 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -22,6 +22,7 @@ java_library(
 ":lists",
 ":math",
 ":protos",
 ":regex",
 ":sets",
 ":sets_function",
 ":strings",
Expand DownExpand Up@@ -241,3 +242,19 @@ java_library(
 "@maven//:com_google_guava_guava",
 ],
)

java_library(
 name = "regex",
 srcs = ["CelRegexExtensions.java"],
 deps = [
 "//checker:checker_builder",
 "//common:compiler_common",
 "//common/types",
 "//compiler:compiler_builder",
 "//runtime",
 "//runtime:function_binding",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 "@maven//:com_google_re2j_re2j",
 ],
)

17 changes: 16 additions & 1 deletion
extensions/src/main/java/dev/cel/extensions/CelExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -36,6 +36,7 @@ public final class CelExtensions {
 private static final CelBindingsExtensions BINDINGS_EXTENSIONS = new CelBindingsExtensions();
 private static final CelEncoderExtensions ENCODER_EXTENSIONS = new CelEncoderExtensions();
 private static final CelListsExtensions LISTS_EXTENSIONS_ALL = new CelListsExtensions();
 private static final CelRegexExtensions REGEX_EXTENSIONS = new CelRegexExtensions();

 /**
 * Extended functions for string manipulation.
Expand DownExpand Up@@ -248,6 +249,18 @@ public static CelListsExtensions lists(Set<CelListsExtensions.Function> function
 return new CelListsExtensions(functions);
 }

 /**
 * Extended functions for Regular Expressions.
 *
 * <p>Refer to README.md for available functions.
 *
 * <p>This will include all functions denoted in {@link CelRegexExtensions.Function}, including
 * any future additions.
 */
 public static CelRegexExtensions regex() {
 return REGEX_EXTENSIONS;
 }

 /**
 * Retrieves all function names used by every extension libraries.
 *
Expand All@@ -265,7 +278,9 @@ public static ImmutableSet<String> getAllFunctionNames() {
 stream(CelEncoderExtensions.Function.values())
 .map(CelEncoderExtensions.Function::getFunction),
 stream(CelListsExtensions.Function.values())
 .map(CelListsExtensions.Function::getFunction))
 .map(CelListsExtensions.Function::getFunction),
 stream(CelRegexExtensions.Function.values())
 .map(CelRegexExtensions.Function::getFunction))
 .collect(toImmutableSet());
 }

Expand Down

266 changes: 266 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/CelRegexExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,266 @@
// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package dev.cel.extensions;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.errorprone.annotations.Immutable;
import com.google.re2j.Matcher;
import com.google.re2j.Pattern;
import com.google.re2j.PatternSyntaxException;
import dev.cel.checker.CelCheckerBuilder;
import dev.cel.common.CelFunctionDecl;
import dev.cel.common.CelOverloadDecl;
import dev.cel.common.types.ListType;
import dev.cel.common.types.MapType;
import dev.cel.common.types.OptionalType;
import dev.cel.common.types.SimpleType;
import dev.cel.compiler.CelCompilerLibrary;
import dev.cel.runtime.CelFunctionBinding;
import dev.cel.runtime.CelRuntimeBuilder;
import dev.cel.runtime.CelRuntimeLibrary;
import java.util.Optional;
import java.util.Set;

/** Internal implementation of CEL regex extensions. */
@Immutable
final class CelRegexExtensions implements CelCompilerLibrary, CelRuntimeLibrary {

 private static final String REGEX_REPLACE_FUNCTION = "regex.replace";
 private static final String REGEX_CAPTURE_FUNCTION = "regex.capture";
 private static final String REGEX_CAPTUREALL_FUNCTION = "regex.captureAll";
 private static final String REGEX_CAPTUREALLNAMED_FUNCTION = "regex.captureAllNamed";

 enum Function {
 REPLACE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_REPLACE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceAll_string_string_string",
 "Replaces all the matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING),
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceCount_string_string_string_int",
 "Replaces the given number of matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.INT)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_replaceAll_string_string_string",
 ImmutableList.of(String.class, String.class, String.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 return CelRegexExtensions.replace(target, pattern, replaceStr);
 }),
 CelFunctionBinding.from(
 "regex_replaceCount_string_string_string_int",
 ImmutableList.of(String.class, String.class, String.class, Long.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 long count = (long) args[3];
 return CelRegexExtensions.replace(target, pattern, replaceStr, count);
 }))),
 CAPTURE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTURE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_capture_string_string",
 "Returns the first substring that matches the regex.",
 OptionalType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_capture_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureFirstMatch))),
 CAPTUREALL(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALL_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAll_string_string",
 "Returns an arrat of all substrings that match the regex.",
 ListType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAll_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllMatches))),
 CAPTUREALLNAMED(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALLNAMED_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAllNamed_string_string",
 "Returns a map of all named captured groups as <named_group_name, captured_string>."
 + " Ignores the unnamed capture groups.",
 MapType.create(SimpleType.STRING, SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAllNamed_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllNamedGroups)));

 private final CelFunctionDecl functionDecl;
 private final ImmutableSet<CelFunctionBinding> functionBindings;

 String getFunction() {
 return functionDecl.name();
 }

 Function(CelFunctionDecl functionDecl, ImmutableSet<CelFunctionBinding> functionBindings) {
 this.functionDecl = functionDecl;
 this.functionBindings = functionBindings;
 }
 }

 private final ImmutableSet<Function> functions;

 CelRegexExtensions() {
 this.functions = ImmutableSet.copyOf(Function.values());
 }

 CelRegexExtensions(Set<Function> functions) {
 this.functions = ImmutableSet.copyOf(functions);
 }

 @Override
 public void setCheckerOptions(CelCheckerBuilder checkerBuilder) {
 functions.forEach(function -> checkerBuilder.addFunctionDeclarations(function.functionDecl));
 }

 @Override
 public void setRuntimeOptions(CelRuntimeBuilder runtimeBuilder) {
 functions.forEach(function -> runtimeBuilder.addFunctionBindings(function.functionBindings));
 }

 private static Pattern compileRegexPattern(String regex) {
 try {
 return Pattern.compile(regex);
 } catch (PatternSyntaxException e) {
 throw new IllegalArgumentException("Failed to compile regex: " + regex, e);
 }
 }

 private static String replace(String target, String regex, String replaceStr) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);
 return matcher.replaceAll(replaceStr);
 }

 private static String replace(String target, String regex, String replaceStr, long replaceCount) {
 Pattern pattern = compileRegexPattern(regex);

 if (replaceCount == 0) {
 return target;
 }

 Matcher matcher = pattern.matcher(target);
 StringBuffer sb = new StringBuffer();
 int counter = 0;

 while (matcher.find()) {
 if (replaceCount != -1 && counter >= replaceCount) {
 break;
 }
 matcher.appendReplacement(sb, replaceStr);
 counter++;
 }
 matcher.appendTail(sb);

 return sb.toString();
 }

 private static Optional<String> captureFirstMatch(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);

 if (matcher.find()) {
 // If there are capture groups, return the first one.
 if (matcher.groupCount() > 0) {
 return Optional.ofNullable(matcher.group(1));
 } else {
 // If there are no capture groups, return the entire match.
 return Optional.of(matcher.group(0));
 }
 }

 return Optional.empty();
 }

 private static ImmutableList<String> captureAllMatches(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);

 Matcher matcher = pattern.matcher(target);
 ImmutableList.Builder<String> builder = ImmutableList.builder();

 while (matcher.find()) {
 // If there are capture groups, return all of them. Otherwise, return the entire match.
 if (matcher.groupCount() > 0) {
 // Add all the capture groups to the result list.
 for (int i = 1; i <= matcher.groupCount(); i++) {
 String group = matcher.group(i);
 if (group != null) {
 builder.add(group);
 }
 }
 } else {
 builder.add(matcher.group(0));
 }
 }

 return builder.build();
 }

 private static ImmutableMap<String, String> captureAllNamedGroups(String target, String regex) {
 ImmutableMap.Builder<String, String> builder = ImmutableMap.builder();
 Pattern pattern = compileRegexPattern(regex);

 Set<String> groupNames = pattern.namedGroups().keySet();
 if (groupNames.isEmpty()) {
 return builder.buildOrThrow();
 }

 Matcher matcher = pattern.matcher(target);

 while (matcher.find()) {

 for (String groupName : groupNames) {
 String capturedValue = matcher.group(groupName);
 if (capturedValue != null) {
 builder.put(groupName, capturedValue);
 }
 }
 }
 return builder.buildOrThrow();
 }
}

6 changes: 5 additions & 1 deletion
extensions/src/test/java/dev/cel/extensions/CelExtensionsTest.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -178,6 +178,10 @@ public void getAllFunctionNames() {
 "base64.decode",
 "base64.encode",
 "flatten",
 "lists.range");
 "lists.range",
 "regex.replace",
 "regex.capture",
 "regex.captureAll",
 "regex.captureAllNamed");
 }
}
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); }
})();
})();

Skip to content
Adding the CEL regex extensions#708

New issue

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

Jun 5, 2025
 Merged


Adding the CEL regex extensions
#708
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Hide file tree
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Filter by extension
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17 changes: 17 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/BUILD.bazel

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -22,6 +22,7 @@ java_library(
 ":lists",
 ":math",
 ":protos",
 ":regex",
 ":sets",
 ":sets_function",
 ":strings",
Expand DownExpand Up@@ -241,3 +242,19 @@ java_library(
 "@maven//:com_google_guava_guava",
 ],
)

java_library(
 name = "regex",
 srcs = ["CelRegexExtensions.java"],
 deps = [
 "//checker:checker_builder",
 "//common:compiler_common",
 "//common/types",
 "//compiler:compiler_builder",
 "//runtime",
 "//runtime:function_binding",
 "@maven//:com_google_errorprone_error_prone_annotations",
 "@maven//:com_google_guava_guava",
 "@maven//:com_google_re2j_re2j",
 ],
)

17 changes: 16 additions & 1 deletion
extensions/src/main/java/dev/cel/extensions/CelExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -36,6 +36,7 @@ public final class CelExtensions {
 private static final CelBindingsExtensions BINDINGS_EXTENSIONS = new CelBindingsExtensions();
 private static final CelEncoderExtensions ENCODER_EXTENSIONS = new CelEncoderExtensions();
 private static final CelListsExtensions LISTS_EXTENSIONS_ALL = new CelListsExtensions();
 private static final CelRegexExtensions REGEX_EXTENSIONS = new CelRegexExtensions();

 /**
 * Extended functions for string manipulation.
Expand DownExpand Up@@ -248,6 +249,18 @@ public static CelListsExtensions lists(Set<CelListsExtensions.Function> function
 return new CelListsExtensions(functions);
 }

 /**
 * Extended functions for Regular Expressions.
 *
 * <p>Refer to README.md for available functions.
 *
 * <p>This will include all functions denoted in {@link CelRegexExtensions.Function}, including
 * any future additions.
 */
 public static CelRegexExtensions regex() {
 return REGEX_EXTENSIONS;
 }

 /**
 * Retrieves all function names used by every extension libraries.
 *
Expand All@@ -265,7 +278,9 @@ public static ImmutableSet<String> getAllFunctionNames() {
 stream(CelEncoderExtensions.Function.values())
 .map(CelEncoderExtensions.Function::getFunction),
 stream(CelListsExtensions.Function.values())
 .map(CelListsExtensions.Function::getFunction))
 .map(CelListsExtensions.Function::getFunction),
 stream(CelRegexExtensions.Function.values())
 .map(CelRegexExtensions.Function::getFunction))
 .collect(toImmutableSet());
 }

Expand Down

266 changes: 266 additions & 0 deletions
extensions/src/main/java/dev/cel/extensions/CelRegexExtensions.java

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,266 @@
// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package dev.cel.extensions;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.errorprone.annotations.Immutable;
import com.google.re2j.Matcher;
import com.google.re2j.Pattern;
import com.google.re2j.PatternSyntaxException;
import dev.cel.checker.CelCheckerBuilder;
import dev.cel.common.CelFunctionDecl;
import dev.cel.common.CelOverloadDecl;
import dev.cel.common.types.ListType;
import dev.cel.common.types.MapType;
import dev.cel.common.types.OptionalType;
import dev.cel.common.types.SimpleType;
import dev.cel.compiler.CelCompilerLibrary;
import dev.cel.runtime.CelFunctionBinding;
import dev.cel.runtime.CelRuntimeBuilder;
import dev.cel.runtime.CelRuntimeLibrary;
import java.util.Optional;
import java.util.Set;

/** Internal implementation of CEL regex extensions. */
@Immutable
final class CelRegexExtensions implements CelCompilerLibrary, CelRuntimeLibrary {

 private static final String REGEX_REPLACE_FUNCTION = "regex.replace";
 private static final String REGEX_CAPTURE_FUNCTION = "regex.capture";
 private static final String REGEX_CAPTUREALL_FUNCTION = "regex.captureAll";
 private static final String REGEX_CAPTUREALLNAMED_FUNCTION = "regex.captureAllNamed";

 enum Function {
 REPLACE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_REPLACE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceAll_string_string_string",
 "Replaces all the matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING),
 CelOverloadDecl.newGlobalOverload(
 "regex_replaceCount_string_string_string_int",
 "Replaces the given number of matched values using the given replace string.",
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.STRING,
 SimpleType.INT)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_replaceAll_string_string_string",
 ImmutableList.of(String.class, String.class, String.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 return CelRegexExtensions.replace(target, pattern, replaceStr);
 }),
 CelFunctionBinding.from(
 "regex_replaceCount_string_string_string_int",
 ImmutableList.of(String.class, String.class, String.class, Long.class),
 (args) -> {
 String target = (String) args[0];
 String pattern = (String) args[1];
 String replaceStr = (String) args[2];
 long count = (long) args[3];
 return CelRegexExtensions.replace(target, pattern, replaceStr, count);
 }))),
 CAPTURE(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTURE_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_capture_string_string",
 "Returns the first substring that matches the regex.",
 OptionalType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_capture_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureFirstMatch))),
 CAPTUREALL(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALL_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAll_string_string",
 "Returns an arrat of all substrings that match the regex.",
 ListType.create(SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAll_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllMatches))),
 CAPTUREALLNAMED(
 CelFunctionDecl.newFunctionDeclaration(
 REGEX_CAPTUREALLNAMED_FUNCTION,
 CelOverloadDecl.newGlobalOverload(
 "regex_captureAllNamed_string_string",
 "Returns a map of all named captured groups as <named_group_name, captured_string>."
 + " Ignores the unnamed capture groups.",
 MapType.create(SimpleType.STRING, SimpleType.STRING),
 SimpleType.STRING,
 SimpleType.STRING)),
 ImmutableSet.of(
 CelFunctionBinding.from(
 "regex_captureAllNamed_string_string",
 String.class,
 String.class,
 CelRegexExtensions::captureAllNamedGroups)));

 private final CelFunctionDecl functionDecl;
 private final ImmutableSet<CelFunctionBinding> functionBindings;

 String getFunction() {
 return functionDecl.name();
 }

 Function(CelFunctionDecl functionDecl, ImmutableSet<CelFunctionBinding> functionBindings) {
 this.functionDecl = functionDecl;
 this.functionBindings = functionBindings;
 }
 }

 private final ImmutableSet<Function> functions;

 CelRegexExtensions() {
 this.functions = ImmutableSet.copyOf(Function.values());
 }

 CelRegexExtensions(Set<Function> functions) {
 this.functions = ImmutableSet.copyOf(functions);
 }

 @Override
 public void setCheckerOptions(CelCheckerBuilder checkerBuilder) {
 functions.forEach(function -> checkerBuilder.addFunctionDeclarations(function.functionDecl));
 }

 @Override
 public void setRuntimeOptions(CelRuntimeBuilder runtimeBuilder) {
 functions.forEach(function -> runtimeBuilder.addFunctionBindings(function.functionBindings));
 }

 private static Pattern compileRegexPattern(String regex) {
 try {
 return Pattern.compile(regex);
 } catch (PatternSyntaxException e) {
 throw new IllegalArgumentException("Failed to compile regex: " + regex, e);
 }
 }

 private static String replace(String target, String regex, String replaceStr) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);
 return matcher.replaceAll(replaceStr);
 }

 private static String replace(String target, String regex, String replaceStr, long replaceCount) {
 Pattern pattern = compileRegexPattern(regex);

 if (replaceCount == 0) {
 return target;
 }

 Matcher matcher = pattern.matcher(target);
 StringBuffer sb = new StringBuffer();
 int counter = 0;

 while (matcher.find()) {
 if (replaceCount != -1 && counter >= replaceCount) {
 break;
 }
 matcher.appendReplacement(sb, replaceStr);
 counter++;
 }
 matcher.appendTail(sb);

 return sb.toString();
 }

 private static Optional<String> captureFirstMatch(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);
 Matcher matcher = pattern.matcher(target);

 if (matcher.find()) {
 // If there are capture groups, return the first one.
 if (matcher.groupCount() > 0) {
 return Optional.ofNullable(matcher.group(1));
 } else {
 // If there are no capture groups, return the entire match.
 return Optional.of(matcher.group(0));
 }
 }

 return Optional.empty();
 }

 private static ImmutableList<String> captureAllMatches(String target, String regex) {
 Pattern pattern = compileRegexPattern(regex);

 Matcher matcher = pattern.matcher(target);
 ImmutableList.Builder<String> builder = ImmutableList.builder();

 while (matcher.find()) {
 // If there are capture groups, return all of them. Otherwise, return the entire match.
 if (matcher.groupCount() > 0) {
 // Add all the capture groups to the result list.
 for (int i = 1; i <= matcher.groupCount(); i++) {
 String group = matcher.group(i);
 if (group != null) {
 builder.add(group);
 }
 }
 } else {
 builder.add(matcher.group(0));
 }
 }

 return builder.build();
 }

 private static ImmutableMap<String, String> captureAllNamedGroups(String target, String regex) {
 ImmutableMap.Builder<String, String> builder = ImmutableMap.builder();
 Pattern pattern = compileRegexPattern(regex);

 Set<String> groupNames = pattern.namedGroups().keySet();
 if (groupNames.isEmpty()) {
 return builder.buildOrThrow();
 }

 Matcher matcher = pattern.matcher(target);

 while (matcher.find()) {

 for (String groupName : groupNames) {
 String capturedValue = matcher.group(groupName);
 if (capturedValue != null) {
 builder.put(groupName, capturedValue);
 }
 }
 }
 return builder.buildOrThrow();
 }
}

6 changes: 5 additions & 1 deletion
extensions/src/test/java/dev/cel/extensions/CelExtensionsTest.java

View file


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Original file line numberDiff line numberDiff line change
Expand Up@@ -178,6 +178,10 @@ public void getAllFunctionNames() {
 "base64.decode",
 "base64.encode",
 "flatten",
 "lists.range");
 "lists.range",
 "regex.replace",
 "regex.capture",
 "regex.captureAll",
 "regex.captureAllNamed");
 }
}
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