fix: source maps

Author: AriPerkkio

packages/coverage-v8/src/intercept-new-run-context.ts

@@ -38,7 +38,6 @@ async function initialize() {
       moduleExecutionInfo: undefined,
     }) as { result: ScriptCoverageWithOffset[] }
 
-    // TODO: Now where do we get source maps
     ws.send(JSON.stringify(coverage.result))
 
     await provider.stopCoverage?.({ isolate: true })

packages/coverage-v8/src/provider.ts

@@ -3,6 +3,8 @@ import type { ProxifiedModule } from 'magicast'
 import type { Profiler } from 'node:inspector'
 import type { CoverageProvider, ReportContext, TestProject, Vite, Vitest } from 'vitest/node'
 import { existsSync, promises as fs } from 'node:fs'
+import { stripTypeScriptTypes } from 'node:module'
+import { extname } from 'node:path'
 import { fileURLToPath } from 'node:url'
 // @ts-expect-error -- untyped
 import { mergeProcessCovs } from '@bcoe/v8-coverage'
@@ -333,6 +335,7 @@ export class V8CoverageProvider extends BaseCoverageProvider implements Coverage
     url: string,
     onTransform: (filepath: string) => Promise<Vite.TransformResult | undefined | null>,
     functions: Profiler.FunctionCoverage[] = [],
+    context = { transformed: true },
   ): Promise<{
     code: string
     map?: Vite.Rollup.SourceMap
@@ -347,16 +350,20 @@ export class V8CoverageProvider extends BaseCoverageProvider implements Coverage
     const map = transformResult?.map as Vite.Rollup.SourceMap | undefined
     const code = transformResult?.code
 
-    if (code == null) {
+    if (code == null || !context.transformed) {
       const filePath = normalize(fileURLToPath(url))
 
-      const original = await fs.readFile(filePath, 'utf-8').catch(() => {
+      let original = await fs.readFile(filePath, 'utf-8').catch(() => {
         // If file does not exist construct a dummy source for it.
         // These can be files that were generated dynamically during the test run and were removed after it.
         const length = findLongestFunctionLength(functions)
         return '/'.repeat(length)
       })
 
+      if (extname(filepath.split('?')[0]) === '.ts') {
+        original = stripTypeScriptTypes(original)
+      }
+
       return { code: original }
     }
 
@@ -436,6 +443,7 @@ export class V8CoverageProvider extends BaseCoverageProvider implements Coverage
             url,
             onTransform,
             functions,
+            { transformed: startOffset !== 0 },
           )
 
           coverageMap.merge(await this.remapCoverage(

test/coverage-test/fixtures/src/worker-or-process.ts

@@ -15,13 +15,31 @@ function execute(options: Options) {
 
 const result = execute({ left: 10, right: 5 });
 
-// v8 ignore else -- testing coverage hints too
 if (isMainThread && process.send) {
+  // Comment
+  interface Padding {
+    left: number;
+    right: number;
+  }
+  // Comment
   process.send({ result });
+  interface Padding2 {
+    left: number;
+    right: number;
+  }
+  // Comment
 }
 else if (parentPort) {
+  // Comment
+  // Comment
+  // Comment
+  // Comment
   parentPort.postMessage({ result });
 }
 else {
-  throw new Error("Where is this running?")
+  // Comment
+  type A = "B"
+  type B = "C"
+  // Comment
+  throw new Error("Where is this running?" as unknown as A | B)
 }

test/coverage-test/fixtures/test/child-process.test.ts

@@ -1,7 +1,10 @@
 import { test , expect } from "vitest"
 import { runFork } from "../src/start-fork-and-thread";
 
-test("child process", async () => {
+test("child process typescript", async () => {
   const result = await runFork();
   expect(result).toBe(5);
 })
+
+test.todo("child process javascript source file")
+test.todo("child process transpiled javascript with source maps")

test/coverage-test/test/extended-run-context.v8.test.ts

@@ -19,6 +19,14 @@ test('{ trackProcessAndWorker: true } includes files from child process', async
       "<process-cwd>/fixtures/src/worker-or-process.ts",
     ]
   `)
+
+  /* See {@link file://./../fixtures/src/worker-or-process.ts} */
+  const fileCoverage = coverageMap.fileCoverageFor('<process-cwd>/fixtures/src/worker-or-process.ts')
+  const lines = fileCoverage.getLineCoverage()
+
+  expect(lines[25]).toBe(1)
+  expect(lines[37]).toBe(0)
+  expect(lines[44]).toBe(0)
 })
 
 test.todo('{ trackProcessAndWorker: true } includes files from worker thread')