test: debug Vite PR 18983

examples/repro/README.md

@@ -0,0 +1,3 @@
+```sh
+VITE_NODE_DEBUG_DUMP=1 pnpm -C examples/repro test -- --coverage
+```

examples/repro/package.json

@@ -0,0 +1,16 @@
+{
+  "name": "@vitest/example-repro",
+  "type": "module",
+  "private": true,
+  "license": "MIT",
+  "scripts": {
+    "test": "vitest"
+  },
+  "devDependencies": {
+    "magic-string": "^0.30.17",
+    "vitest": "latest"
+  },
+  "stackblitz": {
+    "startCommand": "npm run test:ui"
+  }
+}

examples/repro/src/basic.test.ts

@@ -0,0 +1,6 @@
+import { expect, test } from 'vitest'
+import { squared } from './basic'
+
+test('repro', () => {
+  expect(squared(2)).toBe(4)
+})

examples/repro/src/basic.ts

@@ -0,0 +1,2 @@
+export const squared = (n: number) => n * n
+export const cube = (n: number) => n * n * n

examples/repro/vite.config.ts

@@ -0,0 +1,26 @@
+import MagicString from 'magic-string'
+import { defineConfig } from 'vitest/config'
+
+export default defineConfig({
+  test: {
+    coverage: {
+      reporter: ['text', 'text-summary', 'html', 'clover', 'json'],
+    },
+  },
+  plugins: [
+    {
+      name: 'repro',
+      transform(code, id, _options) {
+        if (id.endsWith('/basic.ts')) {
+          const output = new MagicString(code)
+          output.prepend(`function prepended(){};`)
+          output.append(`;function appended(){};`)
+          return {
+            code: output.toString(),
+            map: output.generateMap({ hires: 'boundary' }),
+          }
+        }
+      },
+    },
+  ],
+})

package.json

@@ -62,7 +62,7 @@
     "tinyglobby": "^0.2.10",
     "tsx": "^4.19.2",
     "typescript": "^5.7.2",
-    "vite": "^5.4.0",
+    "vite": "https://pkg.pr.new/vite@059d132",
     "vitest": "workspace:*",
     "zx": "^8.2.4"
   },

packages/coverage-v8/src/provider.ts

@@ -23,6 +23,7 @@ import v8ToIstanbul from 'v8-to-istanbul'
 import { cleanUrl } from 'vite-node/utils'
 
 import { BaseCoverageProvider } from 'vitest/coverage'
+import { offsetToPosition, originalPositionFor, TraceMap } from 'vitest/utils'
 import { version } from '../package.json' with { type: 'json' }
 
 type TransformResults = Map<string, FetchResult>
@@ -277,6 +278,7 @@ export class V8CoverageProvider extends BaseCoverageProvider<ResolvedCoverageOpt
       originalSource: sourcesContent[0],
       source: code || sourcesContent[0],
       sourceMap: {
+        // sourcemap: map,
         sourcemap: excludeGeneratedCode(code, {
           ...map,
           version: 3,
@@ -348,6 +350,32 @@ export class V8CoverageProvider extends BaseCoverageProvider<ResolvedCoverageOpt
 
           // If file was executed by vite-node we'll need to add its wrapper
           const wrapperLength = sources.isExecuted ? WRAPPER_LENGTH : 0
+          // console.log({ sources, wrapperLength, url })
+          // console.log(...functions)
+
+          // filter out functions without mappings,
+          // for example, "export getter" injected by Vite ssr transform.
+          // https://github.com/vitest-dev/vitest/issues/7130
+          if (sources.isExecuted && sources.sourceMap) {
+            const traceMap = new TraceMap(sources.sourceMap.sourcemap)
+            functions = functions.filter((f) => {
+              if (f.ranges.length === 1) {
+                const start = f.ranges[0].startOffset - wrapperLength
+                const end = f.ranges[0].endOffset - wrapperLength
+                if (start < 0) {
+                  return true
+                }
+                const startPos = offsetToPosition(sources.source, start)
+                const endPos = offsetToPosition(sources.source, end)
+                const startSourcePos = originalPositionFor(traceMap, startPos)
+                const endSourcePos = originalPositionFor(traceMap, endPos)
+                if (startSourcePos.line === null && endSourcePos.line === null) {
+                  return false
+                }
+              }
+              return true
+            })
+          }
 
           const converter = v8ToIstanbul(
             url,
@@ -365,6 +393,9 @@ export class V8CoverageProvider extends BaseCoverageProvider<ResolvedCoverageOpt
             this.ctx.logger.error(`Failed to convert coverage for ${url}.\n`, error)
           }
 
+          // const converted = converter.toIstanbul()
+          // console.log(Object.values(converted)[0])
+          // coverageMap.merge(converted)
           coverageMap.merge(converter.toIstanbul())
         }),
       )
@@ -400,7 +431,7 @@ function excludeGeneratedCode(
   }
 
   const trimmed = new MagicString(source)
-  trimmed.replaceAll(VITE_EXPORTS_LINE_PATTERN, '\n')
+  // trimmed.replaceAll(VITE_EXPORTS_LINE_PATTERN, '\n')
   trimmed.replaceAll(DECORATOR_METADATA_PATTERN, match =>
     '\n'.repeat(match.split('\n').length - 1))
 

packages/utils/src/index.ts

@@ -33,6 +33,7 @@ export { nanoid } from './nanoid'
 export {
   lineSplitRE,
   offsetToLineNumber,
+  offsetToPosition,
   positionToOffset,
 } from './offset'
 export { shuffle } from './random'

packages/utils/src/offset.ts

@@ -40,3 +40,25 @@ export function offsetToLineNumber(source: string, offset: number): number {
   }
   return line + 1
 }
+
+export function offsetToPosition(
+  source: string,
+  offset: number,
+): { line: number; column: number } {
+  const lineLengths = source
+    .split(/(?<=\n)|(?<=\r\n)/)
+    .map(line => line.length)
+  let acc = 0
+  for (let i = 0; i < lineLengths.length; i++) {
+    if (offset <= acc + lineLengths[i]) {
+      return {
+        line: i + 1,
+        column: offset - acc,
+      }
+    }
+    acc += lineLengths[i]
+  }
+  throw new Error(
+    `offset is longer than source length! offset ${offset} > length ${source.length}`,
+  )
+}

packages/vite-node/src/source-map.ts

@@ -64,7 +64,7 @@ export function withInlineSourcemap(
   // If the first line is not present on source maps, add simple 1:1 mapping ([0,0,0,0], [1,0,0,0])
   // so that debuggers can be set to break on first line
   if (map.mappings.startsWith(';')) {
-    map.mappings = `AAAA,CAAA${map.mappings}`
+    // map.mappings = `AAAA,CAAA${map.mappings}`
   }
 
   const sourceMap = Buffer.from(JSON.stringify(map), 'utf-8').toString(

packages/vitest/src/utils/source-map.ts

@@ -1,6 +1,7 @@
 export {
   lineSplitRE,
   offsetToLineNumber,
+  offsetToPosition,
   positionToOffset,
 } from '@vitest/utils'
 export {