fix(coverage): apply vite-node's wrapper only to executed files (#5642)

Author: AriPerkkio

Diff for: packages/coverage-v8/src/provider.ts

@@ -310,10 +310,17 @@ export class V8CoverageProvider extends BaseCoverageProvider implements Coverage
     source: string
     originalSource: string
     sourceMap?: { sourcemap: EncodedSourceMap }
+    isExecuted: boolean
   }> {
     const filePath = normalize(fileURLToPath(url))
 
-    const transformResult = transformResults.get(filePath) || await this.ctx.vitenode.transformRequest(filePath).catch(() => {})
+    let isExecuted = true
+    let transformResult: FetchResult | Awaited<ReturnType<typeof this.ctx.vitenode.transformRequest>> = transformResults.get(filePath)
+
+    if (!transformResult) {
+      isExecuted = false
+      transformResult = await this.ctx.vitenode.transformRequest(filePath).catch(() => null)
+    }
 
     const map = transformResult?.map as (EncodedSourceMap | undefined)
     const code = transformResult?.code
@@ -327,6 +334,7 @@ export class V8CoverageProvider extends BaseCoverageProvider implements Coverage
     // These can be uncovered files included by "all: true" or files that are loaded outside vite-node
     if (!map) {
       return {
+        isExecuted,
         source: code || sourcesContent,
         originalSource: sourcesContent,
       }
@@ -337,6 +345,7 @@ export class V8CoverageProvider extends BaseCoverageProvider implements Coverage
       sources[0] = new URL(map.sources[0], url).href
 
     return {
+      isExecuted,
       originalSource: sourcesContent,
       source: code || sourcesContent,
       sourceMap: {
@@ -368,8 +377,8 @@ export class V8CoverageProvider extends BaseCoverageProvider implements Coverage
       await Promise.all(chunk.map(async ({ url, functions }) => {
         const sources = await this.getSources(url, transformResults, functions)
 
-        // If no source map was found from vite-node we can assume this file was not run in the wrapper
-        const wrapperLength = sources.sourceMap ? WRAPPER_LENGTH : 0
+        // If file was executed by vite-node we'll need to add its wrapper
+        const wrapperLength = sources.isExecuted ? WRAPPER_LENGTH : 0
 
         const converter = v8ToIstanbul(url, wrapperLength, sources, undefined, this.options.ignoreEmptyLines)
         await converter.load()

Diff for: test/coverage-test/coverage-report-tests/__snapshots__/istanbul.report.test.ts.snap

@@ -1895,6 +1895,54 @@ exports[`istanbul json report 1`] = `
       },
     },
   },
+  "<process-cwd>/src/load-outside-vite.cjs": {
+    "b": {},
+    "branchMap": {},
+    "f": {
+      "0": 0,
+    },
+    "fnMap": {
+      "0": {
+        "decl": {
+          "end": {
+            "column": 30,
+            "line": 1,
+          },
+          "start": {
+            "column": 26,
+            "line": 1,
+          },
+        },
+        "loc": {
+          "end": {
+            "column": 35,
+            "line": 1,
+          },
+          "start": {
+            "column": 33,
+            "line": 1,
+          },
+        },
+        "name": "noop",
+      },
+    },
+    "path": "<process-cwd>/src/load-outside-vite.cjs",
+    "s": {
+      "0": 0,
+    },
+    "statementMap": {
+      "0": {
+        "end": {
+          "column": 35,
+          "line": 1,
+        },
+        "start": {
+          "column": 0,
+          "line": 1,
+        },
+      },
+    },
+  },
   "<process-cwd>/src/multi-environment.ts": {
     "b": {
       "0": [

Diff for: test/coverage-test/coverage-report-tests/__snapshots__/v8.report.test.ts.snap

@@ -4345,6 +4345,56 @@ exports[`v8 json report 1`] = `
       },
     },
   },
+  "<process-cwd>/src/load-outside-vite.cjs": {
+    "all": false,
+    "b": {},
+    "branchMap": {},
+    "f": {
+      "0": 0,
+    },
+    "fnMap": {
+      "0": {
+        "decl": {
+          "end": {
+            "column": 35,
+            "line": 1,
+          },
+          "start": {
+            "column": 17,
+            "line": 1,
+          },
+        },
+        "line": 1,
+        "loc": {
+          "end": {
+            "column": 35,
+            "line": 1,
+          },
+          "start": {
+            "column": 17,
+            "line": 1,
+          },
+        },
+        "name": "noop",
+      },
+    },
+    "path": "<process-cwd>/src/load-outside-vite.cjs",
+    "s": {
+      "0": 1,
+    },
+    "statementMap": {
+      "0": {
+        "end": {
+          "column": 35,
+          "line": 1,
+        },
+        "start": {
+          "column": 0,
+          "line": 1,
+        },
+      },
+    },
+  },
   "<process-cwd>/src/multi-environment.ts": {
     "all": false,
     "b": {

Diff for: test/coverage-test/src/load-outside-vite.cjs

@@ -0,0 +1 @@
+module.exports = function noop() {}

Diff for: test/coverage-test/test/coverage.test.ts

@@ -84,3 +84,10 @@ test.runIf(provider === 'v8' || provider === 'custom')('pre-transpiled code with
 
   transpiled.hello()
 })
+
+test.runIf(provider === 'v8' || provider === 'custom')('file loaded outside Vite, #5639', async () => {
+  const { Module: { createRequire } } = await import('node:module')
+
+  const noop = createRequire(import.meta.url)('../src/load-outside-vite.cjs')
+  expect(noop).toBeTypeOf('function')
+})