test_runner: calculate executed lines using source map

PR-URL: #53315
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Chemi Atlow <chemi@atlow.co.il>

Author: MoLow

lib/internal/test_runner/coverage.js

@@ -36,14 +36,14 @@ const kLineSplitRegex = /(?<=\r?\n)/u;
 constkStatusRegex=/\/\*node:coverage(?<status>enable|disable)\*\//;
 
 classCoverageLine{
-constructor(line,src,startOffset){
-constnewlineLength=
+constructor(line,startOffset,src,length=src?.length){
+constnewlineLength=src==null ? 0 :
 RegExpPrototypeExec(kLineEndingRegex,src)?.[0].length??0;
 
 this.line=line;
 this.src=src;
 this.startOffset=startOffset;
-this.endOffset=startOffset+src.length-newlineLength;
+this.endOffset=startOffset+length-newlineLength;
 this.ignore=false;
 this.count=this.startOffset===this.endOffset ? 1 : 0;
 }
@@ -83,7 +83,7 @@ class TestCoverage {
 
 constlines=ArrayPrototypeMap(linesWithBreaks,(line,i)=>{
 conststartOffset=offset;
-constcoverageLine=newCoverageLine(i+1,line,startOffset);
+constcoverageLine=newCoverageLine(i+1,startOffset,line);
 
 offset+=line.length;
 
@@ -335,8 +335,13 @@ class TestCoverage {
 newResult.set(url,script);
 continue;
 }
-constoriginalLines=this.getLines(url);
 const{ data, lineLengths }=sourceMapCache[url];
+letoffset=0;
+constexecutedLines=ArrayPrototypeMap(lineLengths,(length,i)=>{
+constcoverageLine=newCoverageLine(i+1,offset,null,length);
+offset+=length;
+returncoverageLine;
+});
 if(data.sourcesContent!=null){
 for(letj=0;j<data.sources.length;++j){
 this.getLines(data.sources[j],data.sourcesContent[j]);
@@ -353,7 +358,7 @@ class TestCoverage {
 constnewRanges=[];
 for(letk=0;k<ranges.length;++k){
 const{ startOffset, endOffset, count }=ranges[k];
-const{ lines }=mapRangeToLines(ranges[k],originalLines);
+const{ lines }=mapRangeToLines(ranges[k],executedLines);
 
 letstartEntry=sourceMap
 .findEntry(lines[0].line-1,MathMax(0,startOffset-lines[0].startOffset));

test/fixtures/test-runner/coverage-loader/hooks.mjs

@@ -1,11 +1,25 @@
-constsource=`
+constsources={
+// Virtual file. Dosen't exist on disk
+"virtual.js": `
  import { test } from 'node:test';
  test('test', async () => {});
-`;
+`,
+// file with source map. this emulates the behavior of tsx
+"sum.test.ts": `\
+import{describe,it}from"node:test";import assert from"node:assert";import{sum}from"./sum.ts";describe("sum",()=>{it("should sum two numbers",()=>{assert.deepStrictEqual(sum(1,2),3)});it("should error out if one is not a number",()=>{assert.throws(()=>sum(1,"b"),Error)})});
+
+//# sourceMappingURL=data:application/json;base64,eyJ2ZXJzaW9uIjozLCJtYXBwaW5ncyI6IkFBQUEsT0FBUyxTQUFVLE9BQVUsWUFDN0IsT0FBTyxXQUFZLGNBQ25CLE9BQVMsUUFBVyxRQUVwQixTQUFTLE1BQU8sSUFBTSxDQUNwQixHQUFHLHlCQUEwQixJQUFNLENBQy9CLE9BQU8sZ0JBQWdCLElBQUksRUFBRSxDQUFDLEVBQUcsQ0FBQyxDQUN0QyxDQUFDLEVBRUQsR0FBRywwQ0FBMkMsSUFBTSxDQUNsRCxPQUFPLE9BQU8sSUFBTSxJQUFJLEVBQUcsR0FBRyxFQUFHLEtBQUssQ0FDeEMsQ0FBQyxDQUNILENBQUMiLCJuYW1lcyI6W10sImlnbm9yZUxpc3QiOltdLCJzb3VyY2VzIjpbIi4vc3VtLnRlc3QudHMiXSwic291cmNlc0NvbnRlbnQiOltudWxsXX0=`,
+// file with source map. this emulates the behavior of tsx
+"sum.ts": `\
+ var __defProp=Object.defineProperty;var __name=(target,value)=>__defProp(target,"name",{value,configurable:true});function sum(...n){if(!n.every(num=>typeof num==="number"))throw new Error("Not a number");return n.reduce((acc,cur)=>acc+cur)}__name(sum,"sum");export{sum};
+
+ //# sourceMappingURL=data:application/json;base64,eyJ2ZXJzaW9uIjozLCJtYXBwaW5ncyI6ImtIQUFPLFNBQVMsT0FBUSxFQUFHLENBQ3pCLEdBQUksQ0FBQyxFQUFFLE1BQU8sS0FBUSxPQUFPLE1BQVEsUUFBUSxFQUFHLE1BQU0sSUFBSSxNQUFNLGNBQWMsRUFDOUUsT0FBTyxFQUFFLE9BQU8sQ0FBQyxJQUFLLE1BQVEsSUFBTSxHQUFHLENBQ3pDLENBSGdCIiwibmFtZXMiOltdLCJpZ25vcmVMaXN0IjpbXSwic291cmNlcyI6WyIuL3N1bS50cyJdLCJzb3VyY2VzQ29udGVudCI6W251bGxdfQ==`,
+};
 
 exportasyncfunctionload(url,context,nextLoad){
-if(url.endsWith('virtual.js')){
-return{format: "module", source,shortCircuit: true};
+constfile=url.split('/').at(-1);
+if(sources[file]!==undefined){
+return{format: "module",source: sources[file],shortCircuit: true};
 }
 returnnextLoad(url,context);
 }

test/fixtures/test-runner/coverage-loader/sum.test.ts

@@ -0,0 +1,13 @@
+import{describe,it}from'node:test'
+importassertfrom'node:assert'
+import{sum}from'./sum'
+
+describe('sum',()=>{
+it('should sum two numbers',()=>{
+assert.deepStrictEqual(sum(1,2),3)
+})
+
+it('should error out if one is not a number',()=>{
+assert.throws(()=>sum(1,'b'),Error)
+})
+})

test/fixtures/test-runner/coverage-loader/sum.ts

@@ -0,0 +1,4 @@
+exportfunctionsum(...n){
+if(!n.every((num)=>typeofnum==='number'))thrownewError('Not a number')
+returnn.reduce((acc,cur)=>acc+cur)
+}

test/parallel/test-runner-coverage.js

@@ -303,3 +303,35 @@ test('coverage with ESM hook - source irrelevant', skipIfNoInspector, () => {
 assert(result.stdout.toString().includes(report));
 assert.strictEqual(result.status,0);
 });
+
+test('coverage with ESM hook - source transpiled',skipIfNoInspector,()=>{
+letreport=[
+'# start of coverage report',
+'# ------------------------------------------------------------------',
+'# file | line % | branch % | funcs % | uncovered lines',
+'# ------------------------------------------------------------------',
+'# hooks.mjs | 100.00 | 100.00 | 100.00 | ',
+'# register-hooks.js | 100.00 | 100.00 | 100.00 | ',
+'# sum.test.ts | 100.00 | 100.00 | 100.00 | ',
+'# sum.ts | 100.00 | 100.00 | 100.00 | ',
+'# ------------------------------------------------------------------',
+'# all files | 100.00 | 100.00 | 100.00 |',
+'# ------------------------------------------------------------------',
+'# end of coverage report',
+].join('\n');
+
+if(common.isWindows){
+report=report.replaceAll('/','\\');
+}
+
+constfixture=fixtures.path('test-runner','coverage-loader');
+constargs=[
+'--import','./register-hooks.js','--test','--experimental-test-coverage',
+'--test-reporter','tap','sum.test.ts',
+];
+constresult=spawnSync(process.execPath,args,{cwd: fixture});
+
+assert.strictEqual(result.stderr.toString(),'');
+assert(result.stdout.toString().includes(report));
+assert.strictEqual(result.status,0);
+});