From ff1600403db8687ec9ade3bf68a667d899b6d83c Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 16:04:57 +0900
Subject: [PATCH 01/15] fix: save and restore module graph in blob reporter

---
 packages/vitest/src/node/reporters/blob.ts | 158 ++++++++++++++++-----
 1 file changed, 123 insertions(+), 35 deletions(-)

diff --git a/packages/vitest/src/node/reporters/blob.ts b/packages/vitest/src/node/reporters/blob.ts
index e2e89ce47985..9beed554b298 100644
--- a/packages/vitest/src/node/reporters/blob.ts
+++ b/packages/vitest/src/node/reporters/blob.ts
@@ -1,5 +1,6 @@
 import type { File } from '@vitest/runner'
 import type { SerializedError } from '@vitest/utils'
+import type { EnvironmentModuleNode } from 'vite'
 import type { Vitest } from '../core'
 import type { TestProject } from '../project'
 import type { Reporter } from '../types/reporter'
@@ -54,27 +55,59 @@ export class BlobReporter implements Reporter {
         : '.vitest-reports/blob.json'
     }
 
-    const modules = this.ctx.projects.map<MergeReportModuleKeys>(
-      (project) => {
-        return [
-          project.name,
-          [...project.vite.moduleGraph.idToModuleMap.entries()].map<SerializedModuleNode | null>((mod) => {
-            if (!mod[1].file) {
-              return null
+    const environmentModules: MergeReportEnvironmentModules = {}
+    this.ctx.projects.forEach((project) => {
+      environmentModules[project.name] = {}
+      Object.entries(project.vite.environments).forEach(([environmentName, environment]) => {
+        const idTable: string[] = []
+        const idMap = new Map<string, number>()
+
+        const getIdIndex = (id: string) => {
+          const existing = idMap.get(id)
+          if (existing != null) {
+            return existing
+          }
+          const next = idTable.length
+          idMap.set(id, next)
+          idTable.push(id)
+          return next
+        }
+
+        const modules: SerializedEnvironmentModuleNode[] = []
+        for (const [id, mod] of environment.moduleGraph.idToModuleMap.entries()) {
+          if (!mod.file) {
+            continue
+          }
+
+          const importedIds: number[] = []
+          for (const importedNode of mod.importedModules) {
+            if (importedNode.id) {
+              importedIds.push(getIdIndex(importedNode.id))
             }
-            return [mod[0], mod[1].file, mod[1].url]
-          }).filter(x => x != null),
-        ]
-      },
-    )
+          }
+
+          modules.push([
+            getIdIndex(id),
+            getIdIndex(mod.file),
+            getIdIndex(mod.url),
+            importedIds,
+          ])
+        }
+
+        environmentModules[project.name][environmentName] = {
+          idTable,
+          modules,
+        }
+      })
+    })
 
     const report = [
       this.ctx.version,
       files,
       errors,
-      modules,
       coverage,
       executionTime,
+      environmentModules,
     ] satisfies MergeReport
 
     const reportFile = resolve(this.ctx.config.root, outputFile)
@@ -112,7 +145,7 @@ export async function readBlobs(
       )
     }
     const content = await readFile(fullPath, 'utf-8')
-    const [version, files, errors, moduleKeys, coverage, executionTime] = parse(
+    const [version, files, errors, coverage, executionTime, environmentModules] = parse(
       content,
     ) as MergeReport
     if (!version) {
@@ -120,7 +153,7 @@ export async function readBlobs(
         `vitest.mergeReports() expects all paths in "${blobsDirectory}" to be files generated by the blob reporter, but "${filename}" is not a valid blob file`,
       )
     }
-    return { version, files, errors, moduleKeys, coverage, file: filename, executionTime }
+    return { version, files, errors, coverage, file: filename, executionTime, environmentModules }
   })
   const blobs = await Promise.all(promises)
 
@@ -143,27 +176,77 @@ export async function readBlobs(
     )
   }
 
-  // fake module graph - it is used to check if module is imported, but we don't use values inside
+  // Restore per-environment module graphs so merge mode can reuse
+  // the same module graph based flows as regular test runs.
   const projects = Object.fromEntries(
     projectsArray.map(p => [p.name, p]),
   )
 
   blobs.forEach((blob) => {
-    blob.moduleKeys.forEach(([projectName, moduleIds]) => {
+    Object.entries(blob.environmentModules).forEach(([projectName, environments]) => {
       const project = projects[projectName]
       if (!project) {
         return
       }
-      moduleIds.forEach(([moduleId, file, url]) => {
-        const moduleNode = project.vite.moduleGraph.createFileOnlyEntry(file)
-        moduleNode.url = url
-        moduleNode.id = moduleId
-        moduleNode.transformResult = {
-          // print error checks that transformResult is set
-          code: ' ',
-          map: null,
+
+      const createdByEnvironment = new Map<string, Map<string, EnvironmentModuleNode>>()
+
+      Object.entries(environments).forEach(([environmentName, moduleGraph]) => {
+        const environment = project.vite.environments[environmentName]
+        if (!environment) {
+          return
         }
-        project.vite.moduleGraph.idToModuleMap.set(moduleId, moduleNode)
+
+        const nodesById = new Map<string, EnvironmentModuleNode>()
+        createdByEnvironment.set(environmentName, nodesById)
+
+        moduleGraph.modules.forEach(([id, file, url]) => {
+          const moduleId = moduleGraph.idTable[id]
+          const filePath = moduleGraph.idTable[file]
+          const urlPath = moduleGraph.idTable[url]
+          if (!moduleId || !filePath || !urlPath) {
+            return
+          }
+          const moduleNode = environment.moduleGraph.createFileOnlyEntry(filePath)
+          moduleNode.url = urlPath
+          moduleNode.id = moduleId
+          moduleNode.transformResult = {
+            code: ' ',
+            map: null,
+          }
+          environment.moduleGraph.idToModuleMap.set(moduleId, moduleNode)
+          nodesById.set(moduleId, moduleNode)
+        })
+      })
+
+      Object.entries(environments).forEach(([environmentName, moduleGraph]) => {
+        const nodesById = createdByEnvironment.get(environmentName)
+        if (!nodesById) {
+          return
+        }
+
+        moduleGraph.modules.forEach(([id, _file, _url, importedIds]) => {
+          const moduleId = moduleGraph.idTable[id]
+          if (!moduleId) {
+            return
+          }
+          const moduleNode = nodesById.get(moduleId)
+          if (!moduleNode) {
+            return
+          }
+          importedIds.forEach((importedIdIndex) => {
+            const importedId = moduleGraph.idTable[importedIdIndex]
+            if (!importedId) {
+              return
+            }
+            const importedNode = nodesById.get(importedId)
+            if (!importedNode) {
+              return
+            }
+            moduleNode.importedModules.add(importedNode)
+            importedNode.importers.add(moduleNode)
+          })
+        })
       })
     })
   })
@@ -198,18 +281,23 @@ type MergeReport = [
   vitestVersion: string,
   files: File[],
   errors: unknown[],
-  modules: MergeReportModuleKeys[],
   coverage: unknown,
   executionTime: number,
+  environmentModules: MergeReportEnvironmentModules,
 ]
 
-type SerializedModuleNode = [
-  id: string,
-  file: string,
-  url: string,
-]
+type MergeReportEnvironmentModules = {
+  [projectName: string]: {
+    [environmentName: string]: {
+      idTable: string[]
+      modules: SerializedEnvironmentModuleNode[]
+    }
+  }
+}
 
-type MergeReportModuleKeys = [
-  projectName: string,
-  modules: SerializedModuleNode[],
+type SerializedEnvironmentModuleNode = [
+  id: number,
+  file: number,
+  url: number,
+  importedIds: number[],
 ]

From a4cbef3fd1e41d2c72b52cc55003698a4e5ab955 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 16:11:13 +0900
Subject: [PATCH 02/15] test: copied from
 https://github.com/vitest-dev/vitest/pull/9728

---
 packages/vitest/src/node/reporters/blob.ts    |  2 +-
 .../merge-reports-module-graph/basic.test.ts  |  8 ++
 .../merge-reports-module-graph/second.test.ts |  6 ++
 .../merge-reports-module-graph/sub/format.ts  |  5 ++
 .../merge-reports-module-graph/sub/subject.ts |  3 +
 .../merge-reports-module-graph/util.ts        |  5 ++
 .../vitest.config.js                          |  1 +
 test/cli/test/reporters/merge-reports.test.ts | 84 ++++++++++++++++++-
 8 files changed, 112 insertions(+), 2 deletions(-)
 create mode 100644 test/cli/fixtures/reporters/merge-reports-module-graph/basic.test.ts
 create mode 100644 test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts
 create mode 100644 test/cli/fixtures/reporters/merge-reports-module-graph/sub/format.ts
 create mode 100644 test/cli/fixtures/reporters/merge-reports-module-graph/sub/subject.ts
 create mode 100644 test/cli/fixtures/reporters/merge-reports-module-graph/util.ts
 create mode 100644 test/cli/fixtures/reporters/merge-reports-module-graph/vitest.config.js

diff --git a/packages/vitest/src/node/reporters/blob.ts b/packages/vitest/src/node/reporters/blob.ts
index 9beed554b298..e0ed34b2d06f 100644
--- a/packages/vitest/src/node/reporters/blob.ts
+++ b/packages/vitest/src/node/reporters/blob.ts
@@ -286,7 +286,7 @@ type MergeReport = [
   environmentModules: MergeReportEnvironmentModules,
 ]
 
-type MergeReportEnvironmentModules = {
+interface MergeReportEnvironmentModules {
   [projectName: string]: {
     [environmentName: string]: {
       idTable: string[]
diff --git a/test/cli/fixtures/reporters/merge-reports-module-graph/basic.test.ts b/test/cli/fixtures/reporters/merge-reports-module-graph/basic.test.ts
new file mode 100644
index 000000000000..c567ed10f00b
--- /dev/null
+++ b/test/cli/fixtures/reporters/merge-reports-module-graph/basic.test.ts
@@ -0,0 +1,8 @@
+import { test, expect } from 'vitest'
+import { formatHello } from './sub/format'
+import { hello } from './util'
+
+test('passes', () => {
+  expect(hello()).toBe('Hello, graph!')
+  expect(formatHello()).toBe('Hello, graph!')
+})
diff --git a/test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts b/test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts
new file mode 100644
index 000000000000..538861171d37
--- /dev/null
+++ b/test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts
@@ -0,0 +1,6 @@
+import { test, expect } from 'vitest'
+import { hello } from './util'
+
+test('also passes', () => {
+  expect(hello()).toBe('Hello, graph!')
+})
diff --git a/test/cli/fixtures/reporters/merge-reports-module-graph/sub/format.ts b/test/cli/fixtures/reporters/merge-reports-module-graph/sub/format.ts
new file mode 100644
index 000000000000..f653729ee14b
--- /dev/null
+++ b/test/cli/fixtures/reporters/merge-reports-module-graph/sub/format.ts
@@ -0,0 +1,5 @@
+import { getSubject } from './subject'
+
+export function formatHello() {
+  return `Hello, ${getSubject()}!`
+}
diff --git a/test/cli/fixtures/reporters/merge-reports-module-graph/sub/subject.ts b/test/cli/fixtures/reporters/merge-reports-module-graph/sub/subject.ts
new file mode 100644
index 000000000000..7a7bc073b1c3
--- /dev/null
+++ b/test/cli/fixtures/reporters/merge-reports-module-graph/sub/subject.ts
@@ -0,0 +1,3 @@
+export function getSubject() {
+  return 'graph'
+}
diff --git a/test/cli/fixtures/reporters/merge-reports-module-graph/util.ts b/test/cli/fixtures/reporters/merge-reports-module-graph/util.ts
new file mode 100644
index 000000000000..49981c185118
--- /dev/null
+++ b/test/cli/fixtures/reporters/merge-reports-module-graph/util.ts
@@ -0,0 +1,5 @@
+import { getSubject } from './sub/subject'
+
+export function hello() {
+  return `Hello, ${getSubject()}!`
+}
diff --git a/test/cli/fixtures/reporters/merge-reports-module-graph/vitest.config.js b/test/cli/fixtures/reporters/merge-reports-module-graph/vitest.config.js
new file mode 100644
index 000000000000..b1c6ea436a54
--- /dev/null
+++ b/test/cli/fixtures/reporters/merge-reports-module-graph/vitest.config.js
@@ -0,0 +1 @@
+export default {}
diff --git a/test/cli/test/reporters/merge-reports.test.ts b/test/cli/test/reporters/merge-reports.test.ts
index e52f6c0e2129..38f1c4777e5d 100644
--- a/test/cli/test/reporters/merge-reports.test.ts
+++ b/test/cli/test/reporters/merge-reports.test.ts
@@ -6,6 +6,7 @@ import { createFileTask } from '@vitest/runner/utils'
 import { beforeEach, expect, test } from 'vitest'
 import { version } from 'vitest/package.json'
 import { writeBlob } from 'vitest/src/node/reporters/blob.js'
+import { getModuleGraph } from '../../../../packages/vitest/src/utils/graph'
 
 // always relative to CWD because it's used only from the CLI,
 // so we need to correctly resolve it here
@@ -254,7 +255,7 @@ test('total and merged execution times are shown', async () => {
     file.tasks.push(createTest('some test', file))
 
     await writeBlob(
-      [version, [file], [], [], undefined, 1500 * index],
+      [version, [file], [], undefined, 1500 * index, {}],
       resolve(`./fixtures/reporters/merge-reports/.vitest-reports/blob-${index}-2.json`),
     )
   }
@@ -272,6 +273,87 @@ test('total and merged execution times are shown', async () => {
   expect(stdout).toContain('Per blob  1.50s 3.00s')
 })
 
+test('module graph available', async () => {
+  const root = resolve('./fixtures/reporters/merge-reports-module-graph')
+  const reportsDir = resolve(root, '.vitest-reports')
+  rmSync(reportsDir, { force: true, recursive: true })
+
+  // generate blob
+  await runVitest({
+    root,
+    reporters: ['blob'],
+  })
+
+  // test restored blob has module graph
+  const { stderr, ctx } = await runVitest({
+    root,
+    mergeReports: reportsDir,
+  })
+  expect(stderr).toMatchInlineSnapshot(`""`)
+  expect.assert(ctx)
+  // TODO: test with getModuleGraph
+  expect.assert(getModuleGraph)
+  // const moduleGraphJson = JSON.stringify(ctx.state.blobs?.moduleGraphData, null, 2).replaceAll(ctx.config.root, '<root>')
+  // expect(moduleGraphJson).toMatchInlineSnapshot(`
+  //   "{
+  //     "": {
+  //       "<root>/basic.test.ts": {
+  //         "graph": {
+  //           "<root>/sub/subject.ts": [],
+  //           "<root>/sub/format.ts": [
+  //             "<root>/sub/subject.ts"
+  //           ],
+  //           "<root>/util.ts": [
+  //             "<root>/sub/subject.ts"
+  //           ],
+  //           "<root>/basic.test.ts": [
+  //             "<root>/sub/format.ts",
+  //             "<root>/util.ts"
+  //           ]
+  //         },
+  //         "externalized": [],
+  //         "inlined": [
+  //           "<root>/basic.test.ts",
+  //           "<root>/sub/format.ts",
+  //           "<root>/sub/subject.ts",
+  //           "<root>/util.ts"
+  //         ]
+  //       },
+  //       "<root>/second.test.ts": {
+  //         "graph": {
+  //           "<root>/sub/subject.ts": [],
+  //           "<root>/util.ts": [
+  //             "<root>/sub/subject.ts"
+  //           ],
+  //           "<root>/second.test.ts": [
+  //             "<root>/util.ts"
+  //           ]
+  //         },
+  //         "externalized": [],
+  //         "inlined": [
+  //           "<root>/second.test.ts",
+  //           "<root>/util.ts",
+  //           "<root>/sub/subject.ts"
+  //         ]
+  //       }
+  //     }
+  //   }"
+  // `)
+
+  // also check html reporter doesn't crash
+  const result = await runVitest({
+    root,
+    mergeReports: resolve(root, '.vitest-reports'),
+    reporters: ['html'],
+  })
+  expect(result.stderr).toMatchInlineSnapshot(`""`)
+  expect(result.stdout).toMatchInlineSnapshot(`
+    " HTML  Report is generated
+           You can run npx vite preview --outDir html to see the test results.
+    "
+  `)
+})
+
 function trimReporterOutput(report: string) {
   const rows = report
     .replace(/\d+ms/g, '<time>')

From 26187f155f3ad7c478defc4d357d3694e60e469e Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 16:24:47 +0900
Subject: [PATCH 03/15] test: verify module graph

---
 .../merge-reports-module-graph/second.test.ts |   5 +
 test/cli/test/reporters/merge-reports.test.ts | 102 +++++++++---------
 2 files changed, 59 insertions(+), 48 deletions(-)

diff --git a/test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts b/test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts
index 538861171d37..3af7ee0bf433 100644
--- a/test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts
+++ b/test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts
@@ -1,6 +1,11 @@
 import { test, expect } from 'vitest'
 import { hello } from './util'
+// import * as obug from "obug"
 
 test('also passes', () => {
   expect(hello()).toBe('Hello, graph!')
 })
+
+// test('external', () => {
+//   expect(obug).toBeTypeOf('object')
+// })
diff --git a/test/cli/test/reporters/merge-reports.test.ts b/test/cli/test/reporters/merge-reports.test.ts
index 38f1c4777e5d..9705f8abfe93 100644
--- a/test/cli/test/reporters/merge-reports.test.ts
+++ b/test/cli/test/reporters/merge-reports.test.ts
@@ -290,55 +290,61 @@ test('module graph available', async () => {
     mergeReports: reportsDir,
   })
   expect(stderr).toMatchInlineSnapshot(`""`)
+
   expect.assert(ctx)
-  // TODO: test with getModuleGraph
-  expect.assert(getModuleGraph)
-  // const moduleGraphJson = JSON.stringify(ctx.state.blobs?.moduleGraphData, null, 2).replaceAll(ctx.config.root, '<root>')
-  // expect(moduleGraphJson).toMatchInlineSnapshot(`
-  //   "{
-  //     "": {
-  //       "<root>/basic.test.ts": {
-  //         "graph": {
-  //           "<root>/sub/subject.ts": [],
-  //           "<root>/sub/format.ts": [
-  //             "<root>/sub/subject.ts"
-  //           ],
-  //           "<root>/util.ts": [
-  //             "<root>/sub/subject.ts"
-  //           ],
-  //           "<root>/basic.test.ts": [
-  //             "<root>/sub/format.ts",
-  //             "<root>/util.ts"
-  //           ]
-  //         },
-  //         "externalized": [],
-  //         "inlined": [
-  //           "<root>/basic.test.ts",
-  //           "<root>/sub/format.ts",
-  //           "<root>/sub/subject.ts",
-  //           "<root>/util.ts"
-  //         ]
-  //       },
-  //       "<root>/second.test.ts": {
-  //         "graph": {
-  //           "<root>/sub/subject.ts": [],
-  //           "<root>/util.ts": [
-  //             "<root>/sub/subject.ts"
-  //           ],
-  //           "<root>/second.test.ts": [
-  //             "<root>/util.ts"
-  //           ]
-  //         },
-  //         "externalized": [],
-  //         "inlined": [
-  //           "<root>/second.test.ts",
-  //           "<root>/util.ts",
-  //           "<root>/sub/subject.ts"
-  //         ]
-  //       }
-  //     }
-  //   }"
-  // `)
+  const files = ctx.state.getFiles().map(file => file.filepath).sort()
+  const moduleGraphs = Object.fromEntries(
+    await Promise.all(
+      files.map(async (file) => {
+        const graph = await getModuleGraph(ctx, '', file)
+        return [file, graph]
+      }),
+    ),
+  )
+  const moduleGraphJson = JSON.stringify(moduleGraphs, null, 2).replaceAll(ctx.config.root, '<root>')
+  expect(moduleGraphJson).toMatchInlineSnapshot(`
+    "{
+      "<root>/basic.test.ts": {
+        "graph": {
+          "<root>/sub/subject.ts": [],
+          "<root>/sub/format.ts": [
+            "<root>/sub/subject.ts"
+          ],
+          "<root>/util.ts": [
+            "<root>/sub/subject.ts"
+          ],
+          "<root>/basic.test.ts": [
+            "<root>/sub/format.ts",
+            "<root>/util.ts"
+          ]
+        },
+        "externalized": [],
+        "inlined": [
+          "<root>/basic.test.ts",
+          "<root>/sub/format.ts",
+          "<root>/sub/subject.ts",
+          "<root>/util.ts"
+        ]
+      },
+      "<root>/second.test.ts": {
+        "graph": {
+          "<root>/sub/subject.ts": [],
+          "<root>/util.ts": [
+            "<root>/sub/subject.ts"
+          ],
+          "<root>/second.test.ts": [
+            "<root>/util.ts"
+          ]
+        },
+        "externalized": [],
+        "inlined": [
+          "<root>/second.test.ts",
+          "<root>/util.ts",
+          "<root>/sub/subject.ts"
+        ]
+      }
+    }"
+  `)
 
   // also check html reporter doesn't crash
   const result = await runVitest({

From bc4b9279a071d9f644a896b7cd4a00372eae7a9e Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 16:31:17 +0900
Subject: [PATCH 04/15] test: before and after

---
 test/cli/test/reporters/merge-reports.test.ts | 56 ++++++++++++-------
 1 file changed, 35 insertions(+), 21 deletions(-)

diff --git a/test/cli/test/reporters/merge-reports.test.ts b/test/cli/test/reporters/merge-reports.test.ts
index 9705f8abfe93..bf36ca0c525c 100644
--- a/test/cli/test/reporters/merge-reports.test.ts
+++ b/test/cli/test/reporters/merge-reports.test.ts
@@ -1,4 +1,5 @@
 import type { File, Test } from '@vitest/runner/types'
+import type { Vitest } from 'vitest/node'
 import { rmSync } from 'node:fs'
 import { resolve } from 'node:path'
 import { runVitest } from '#test-utils'
@@ -278,31 +279,34 @@ test('module graph available', async () => {
   const reportsDir = resolve(root, '.vitest-reports')
   rmSync(reportsDir, { force: true, recursive: true })
 
+  async function getModuleGraphs(ctx: Vitest) {
+    const files = ctx.state.getFiles().slice().sort((a, b) => a.filepath.localeCompare(b.filepath))
+    const moduleGraphs = Object.fromEntries(
+      await Promise.all(
+        files.map(async (file) => {
+          const projectName = file.projectName || ''
+          const project = ctx.getProjectByName(projectName)
+          const graph = await getModuleGraph(
+            ctx,
+            projectName,
+            file.filepath,
+            project.config.browser.enabled,
+          )
+          return [file.filepath, graph] as const
+        }),
+      ),
+    )
+    return JSON.stringify(moduleGraphs, null, 2).replaceAll(ctx.config.root, '<root>')
+  }
+
   // generate blob
-  await runVitest({
+  const result1 = await runVitest({
     root,
     reporters: ['blob'],
   })
-
-  // test restored blob has module graph
-  const { stderr, ctx } = await runVitest({
-    root,
-    mergeReports: reportsDir,
-  })
-  expect(stderr).toMatchInlineSnapshot(`""`)
-
-  expect.assert(ctx)
-  const files = ctx.state.getFiles().map(file => file.filepath).sort()
-  const moduleGraphs = Object.fromEntries(
-    await Promise.all(
-      files.map(async (file) => {
-        const graph = await getModuleGraph(ctx, '', file)
-        return [file, graph]
-      }),
-    ),
-  )
-  const moduleGraphJson = JSON.stringify(moduleGraphs, null, 2).replaceAll(ctx.config.root, '<root>')
-  expect(moduleGraphJson).toMatchInlineSnapshot(`
+  expect.assert(result1.ctx)
+  const generatedModuleGraphJson = await getModuleGraphs(result1.ctx)
+  expect(generatedModuleGraphJson).toMatchInlineSnapshot(`
     "{
       "<root>/basic.test.ts": {
         "graph": {
@@ -346,6 +350,16 @@ test('module graph available', async () => {
     }"
   `)
 
+  // test restored blob has module graph
+  const { stderr, ctx } = await runVitest({
+    root,
+    mergeReports: reportsDir,
+  })
+  expect(stderr).toMatchInlineSnapshot(`""`)
+  expect.assert(ctx)
+  const restoredModuleGraphJson = await getModuleGraphs(ctx)
+  expect(restoredModuleGraphJson).toBe(generatedModuleGraphJson)
+
   // also check html reporter doesn't crash
   const result = await runVitest({
     root,

From 62221850db8d5bf5ec1150c79a5ca077c220b57f Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 16:33:00 +0900
Subject: [PATCH 05/15] test: rename merge-reports module graph run results

---
 test/cli/test/reporters/merge-reports.test.ts | 20 +++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/test/cli/test/reporters/merge-reports.test.ts b/test/cli/test/reporters/merge-reports.test.ts
index bf36ca0c525c..82ac9b6e8236 100644
--- a/test/cli/test/reporters/merge-reports.test.ts
+++ b/test/cli/test/reporters/merge-reports.test.ts
@@ -300,12 +300,12 @@ test('module graph available', async () => {
   }
 
   // generate blob
-  const result1 = await runVitest({
+  const result = await runVitest({
     root,
     reporters: ['blob'],
   })
-  expect.assert(result1.ctx)
-  const generatedModuleGraphJson = await getModuleGraphs(result1.ctx)
+  expect.assert(result.ctx)
+  const generatedModuleGraphJson = await getModuleGraphs(result.ctx)
   expect(generatedModuleGraphJson).toMatchInlineSnapshot(`
     "{
       "<root>/basic.test.ts": {
@@ -351,23 +351,23 @@ test('module graph available', async () => {
   `)
 
   // test restored blob has module graph
-  const { stderr, ctx } = await runVitest({
+  const result2 = await runVitest({
     root,
     mergeReports: reportsDir,
   })
-  expect(stderr).toMatchInlineSnapshot(`""`)
-  expect.assert(ctx)
-  const restoredModuleGraphJson = await getModuleGraphs(ctx)
+  expect(result2.stderr).toMatchInlineSnapshot(`""`)
+  expect.assert(result2.ctx)
+  const restoredModuleGraphJson = await getModuleGraphs(result2.ctx)
   expect(restoredModuleGraphJson).toBe(generatedModuleGraphJson)
 
   // also check html reporter doesn't crash
-  const result = await runVitest({
+  const result3 = await runVitest({
     root,
     mergeReports: resolve(root, '.vitest-reports'),
     reporters: ['html'],
   })
-  expect(result.stderr).toMatchInlineSnapshot(`""`)
-  expect(result.stdout).toMatchInlineSnapshot(`
+  expect(result3.stderr).toMatchInlineSnapshot(`""`)
+  expect(result3.stdout).toMatchInlineSnapshot(`
     " HTML  Report is generated
            You can run npx vite preview --outDir html to see the test results.
     "

From eb541a70457604661fe08db10ada5375cf67f295 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 16:53:30 +0900
Subject: [PATCH 06/15] fix: fix external

---
 packages/vitest/src/node/reporters/blob.ts    | 30 +++++++++++++++++--
 packages/vitest/src/node/resolver.ts          |  2 +-
 .../merge-reports-module-graph/second.test.ts |  8 ++---
 test/cli/test/reporters/merge-reports.test.ts | 21 ++++++++-----
 4 files changed, 46 insertions(+), 15 deletions(-)

diff --git a/packages/vitest/src/node/reporters/blob.ts b/packages/vitest/src/node/reporters/blob.ts
index e0ed34b2d06f..2d7debadf3cc 100644
--- a/packages/vitest/src/node/reporters/blob.ts
+++ b/packages/vitest/src/node/reporters/blob.ts
@@ -101,6 +101,16 @@ export class BlobReporter implements Reporter {
       })
     })
 
+    const externalized: SerializedExternalizedByProject = {}
+    this.ctx.projects.forEach((project) => {
+      externalized[project.name] = []
+      for (const [k, v] of project._resolver.externalizeCache.entries()) {
+        if (typeof v === 'string') {
+          externalized[project.name].push([k, v])
+        }
+      }
+    })
+
     const report = [
       this.ctx.version,
       files,
@@ -108,6 +118,7 @@ export class BlobReporter implements Reporter {
       coverage,
       executionTime,
       environmentModules,
+      externalized,
     ] satisfies MergeReport
 
     const reportFile = resolve(this.ctx.config.root, outputFile)
@@ -145,7 +156,7 @@ export async function readBlobs(
       )
     }
     const content = await readFile(fullPath, 'utf-8')
-    const [version, files, errors, coverage, executionTime, environmentModules] = parse(
+    const [version, files, errors, coverage, executionTime, environmentModules, externalized] = parse(
       content,
     ) as MergeReport
     if (!version) {
@@ -153,7 +164,7 @@ export async function readBlobs(
         `vitest.mergeReports() expects all paths in "${blobsDirectory}" to be files generated by the blob reporter, but "${filename}" is not a valid blob file`,
       )
     }
-    return { version, files, errors, coverage, file: filename, executionTime, environmentModules }
+    return { version, files, errors, coverage, file: filename, executionTime, environmentModules, externalized }
   })
   const blobs = await Promise.all(promises)
 
@@ -183,6 +194,16 @@ export async function readBlobs(
   )
 
   blobs.forEach((blob) => {
+    Object.entries(blob.externalized).forEach(([projectName, entries]) => {
+      const project = projects[projectName]
+      if (!project) {
+        return
+      }
+      entries.forEach(([id, externalized]) => {
+        project._resolver.externalizeCache.set(id, externalized)
+      })
+    })
+
     Object.entries(blob.environmentModules).forEach(([projectName, environments]) => {
       const project = projects[projectName]
       if (!project) {
@@ -284,6 +305,7 @@ type MergeReport = [
   coverage: unknown,
   executionTime: number,
   environmentModules: MergeReportEnvironmentModules,
+  externalized: SerializedExternalizedByProject,
 ]
 
 interface MergeReportEnvironmentModules {
@@ -295,6 +317,10 @@ interface MergeReportEnvironmentModules {
   }
 }
 
+interface SerializedExternalizedByProject {
+  [projectName: string]: [id: string, externalized: string][]
+}
+
 type SerializedEnvironmentModuleNode = [
   id: number,
   file: number,
diff --git a/packages/vitest/src/node/resolver.ts b/packages/vitest/src/node/resolver.ts
index 09443df349ae..658aa4ea5b93 100644
--- a/packages/vitest/src/node/resolver.ts
+++ b/packages/vitest/src/node/resolver.ts
@@ -12,7 +12,7 @@ import { isWindows } from '../utils/env'
 export class VitestResolver {
   public readonly options: ExternalizeOptions
   private externalizeConcurrentCache = new Map<string, Promise<string | false | undefined>>()
-  private externalizeCache = new Map<string, string | false | undefined>()
+  public externalizeCache: Map<string, string | false | undefined> = new Map<string, string | false | undefined>()
 
   constructor(cacheDir: string, config: ResolvedConfig) {
     // sorting to make cache consistent
diff --git a/test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts b/test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts
index 3af7ee0bf433..b08172727353 100644
--- a/test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts
+++ b/test/cli/fixtures/reporters/merge-reports-module-graph/second.test.ts
@@ -1,11 +1,11 @@
 import { test, expect } from 'vitest'
 import { hello } from './util'
-// import * as obug from "obug"
+import * as obug from "obug"
 
 test('also passes', () => {
   expect(hello()).toBe('Hello, graph!')
 })
 
-// test('external', () => {
-//   expect(obug).toBeTypeOf('object')
-// })
+test('external', () => {
+  expect(obug).toBeTypeOf('object')
+})
diff --git a/test/cli/test/reporters/merge-reports.test.ts b/test/cli/test/reporters/merge-reports.test.ts
index 82ac9b6e8236..6b2cf56410aa 100644
--- a/test/cli/test/reporters/merge-reports.test.ts
+++ b/test/cli/test/reporters/merge-reports.test.ts
@@ -256,7 +256,7 @@ test('total and merged execution times are shown', async () => {
     file.tasks.push(createTest('some test', file))
 
     await writeBlob(
-      [version, [file], [], undefined, 1500 * index, {}],
+      [version, [file], [], undefined, 1500 * index, {}, {}],
       resolve(`./fixtures/reporters/merge-reports/.vitest-reports/blob-${index}-2.json`),
     )
   }
@@ -279,8 +279,8 @@ test('module graph available', async () => {
   const reportsDir = resolve(root, '.vitest-reports')
   rmSync(reportsDir, { force: true, recursive: true })
 
-  async function getModuleGraphs(ctx: Vitest) {
-    const files = ctx.state.getFiles().slice().sort((a, b) => a.filepath.localeCompare(b.filepath))
+  async function getSerializedModuleGraph(ctx: Vitest) {
+    const files = ctx.state.getFiles().slice().sort()
     const moduleGraphs = Object.fromEntries(
       await Promise.all(
         files.map(async (file) => {
@@ -296,7 +296,9 @@ test('module graph available', async () => {
         }),
       ),
     )
-    return JSON.stringify(moduleGraphs, null, 2).replaceAll(ctx.config.root, '<root>')
+    return JSON.stringify(moduleGraphs, null, 2)
+      .replaceAll(ctx.config.root, '<root>')
+      .replace(/"\/[^"\n]*\/node_modules\//g, '"<node_modules>/')
   }
 
   // generate blob
@@ -305,7 +307,7 @@ test('module graph available', async () => {
     reporters: ['blob'],
   })
   expect.assert(result.ctx)
-  const generatedModuleGraphJson = await getModuleGraphs(result.ctx)
+  const generatedModuleGraphJson = await getSerializedModuleGraph(result.ctx)
   expect(generatedModuleGraphJson).toMatchInlineSnapshot(`
     "{
       "<root>/basic.test.ts": {
@@ -337,10 +339,13 @@ test('module graph available', async () => {
             "<root>/sub/subject.ts"
           ],
           "<root>/second.test.ts": [
-            "<root>/util.ts"
+            "<root>/util.ts",
+            "<node_modules>/obug/dist/node.js"
           ]
         },
-        "externalized": [],
+        "externalized": [
+          "<node_modules>/obug/dist/node.js"
+        ],
         "inlined": [
           "<root>/second.test.ts",
           "<root>/util.ts",
@@ -357,7 +362,7 @@ test('module graph available', async () => {
   })
   expect(result2.stderr).toMatchInlineSnapshot(`""`)
   expect.assert(result2.ctx)
-  const restoredModuleGraphJson = await getModuleGraphs(result2.ctx)
+  const restoredModuleGraphJson = await getSerializedModuleGraph(result2.ctx)
   expect(restoredModuleGraphJson).toBe(generatedModuleGraphJson)
 
   // also check html reporter doesn't crash

From 0bf12d3aabc1ebef25414cc13c1db72ec3d20cbb Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 17:50:25 +0900
Subject: [PATCH 07/15] fix: save browser module graph

---
 packages/vitest/src/node/reporters/blob.ts    | 280 ++++++++++--------
 test/cli/test/reporters/merge-reports.test.ts |   4 +-
 2 files changed, 159 insertions(+), 125 deletions(-)

diff --git a/packages/vitest/src/node/reporters/blob.ts b/packages/vitest/src/node/reporters/blob.ts
index 2d7debadf3cc..ffc7d4fbe443 100644
--- a/packages/vitest/src/node/reporters/blob.ts
+++ b/packages/vitest/src/node/reporters/blob.ts
@@ -1,6 +1,6 @@
 import type { File } from '@vitest/runner'
 import type { SerializedError } from '@vitest/utils'
-import type { EnvironmentModuleNode } from 'vite'
+import type { DevEnvironment, EnvironmentModuleNode } from 'vite'
 import type { Vitest } from '../core'
 import type { TestProject } from '../project'
 import type { Reporter } from '../types/reporter'
@@ -57,58 +57,29 @@ export class BlobReporter implements Reporter {
 
     const environmentModules: MergeReportEnvironmentModules = {}
     this.ctx.projects.forEach((project) => {
-      environmentModules[project.name] = {}
+      const serializedProject: MergeReportEnvironmentModules[string] = {
+        environments: {},
+        external: [],
+      }
       Object.entries(project.vite.environments).forEach(([environmentName, environment]) => {
-        const idTable: string[] = []
-        const idMap = new Map<string, number>()
-
-        const getIdIndex = (id: string) => {
-          const existing = idMap.get(id)
-          if (existing != null) {
-            return existing
-          }
-          const next = idTable.length
-          idMap.set(id, next)
-          idTable.push(id)
-          return next
-        }
-
-        const modules: SerializedEnvironmentModuleNode[] = []
-        for (const [id, mod] of environment.moduleGraph.idToModuleMap.entries()) {
-          if (!mod.file) {
-            continue
-          }
-
-          const importedIds: number[] = []
-          for (const importedNode of mod.importedModules) {
-            if (importedNode.id) {
-              importedIds.push(getIdIndex(importedNode.id))
-            }
-          }
-
-          modules.push([
-            getIdIndex(id),
-            getIdIndex(mod.file),
-            getIdIndex(mod.url),
-            importedIds,
-          ])
-        }
-
-        environmentModules[project.name][environmentName] = {
-          idTable,
-          modules,
-        }
+        serializedProject.environments[environmentName] = serializeEnvironmentModuleGraph(
+          environment,
+        )
       })
-    })
 
-    const externalized: SerializedExternalizedByProject = {}
-    this.ctx.projects.forEach((project) => {
-      externalized[project.name] = []
-      for (const [k, v] of project._resolver.externalizeCache.entries()) {
-        if (typeof v === 'string') {
-          externalized[project.name].push([k, v])
+      if (project.browser?.vite.environments.client) {
+        serializedProject.browser = serializeEnvironmentModuleGraph(
+          project.browser.vite.environments.client,
+        )
+      }
+
+      for (const [id, value] of project._resolver.externalizeCache.entries()) {
+        if (typeof value === 'string') {
+          serializedProject.external.push([id, value])
         }
       }
+
+      environmentModules[project.name] = serializedProject
     })
 
     const report = [
@@ -118,7 +89,6 @@ export class BlobReporter implements Reporter {
       coverage,
       executionTime,
       environmentModules,
-      externalized,
     ] satisfies MergeReport
 
     const reportFile = resolve(this.ctx.config.root, outputFile)
@@ -156,7 +126,7 @@ export async function readBlobs(
       )
     }
     const content = await readFile(fullPath, 'utf-8')
-    const [version, files, errors, coverage, executionTime, environmentModules, externalized] = parse(
+    const [version, files, errors, coverage, executionTime, environmentModules] = parse(
       content,
     ) as MergeReport
     if (!version) {
@@ -164,7 +134,7 @@ export async function readBlobs(
         `vitest.mergeReports() expects all paths in "${blobsDirectory}" to be files generated by the blob reporter, but "${filename}" is not a valid blob file`,
       )
     }
-    return { version, files, errors, coverage, file: filename, executionTime, environmentModules, externalized }
+    return { version, files, errors, coverage, file: filename, executionTime, environmentModules }
   })
   const blobs = await Promise.all(promises)
 
@@ -194,81 +164,35 @@ export async function readBlobs(
   )
 
   blobs.forEach((blob) => {
-    Object.entries(blob.externalized).forEach(([projectName, entries]) => {
+    Object.entries(blob.environmentModules).forEach(([projectName, modulesByProject]) => {
       const project = projects[projectName]
       if (!project) {
         return
       }
-      entries.forEach(([id, externalized]) => {
+
+      modulesByProject.external.forEach(([id, externalized]) => {
         project._resolver.externalizeCache.set(id, externalized)
       })
-    })
 
-    Object.entries(blob.environmentModules).forEach(([projectName, environments]) => {
-      const project = projects[projectName]
-      if (!project) {
-        return
-      }
-
-      const createdByEnvironment = new Map<string, Map<string, EnvironmentModuleNode>>()
-
-      Object.entries(environments).forEach(([environmentName, moduleGraph]) => {
+      Object.entries(modulesByProject.environments).forEach(([environmentName, moduleGraph]) => {
         const environment = project.vite.environments[environmentName]
-        if (!environment) {
-          return
-        }
-
-        const nodesById = new Map<string, EnvironmentModuleNode>()
-        createdByEnvironment.set(environmentName, nodesById)
-
-        moduleGraph.modules.forEach(([id, file, url]) => {
-          const moduleId = moduleGraph.idTable[id]
-          const filePath = moduleGraph.idTable[file]
-          const urlPath = moduleGraph.idTable[url]
-          if (!moduleId || !filePath || !urlPath) {
-            return
-          }
-          const moduleNode = environment.moduleGraph.createFileOnlyEntry(filePath)
-          moduleNode.url = urlPath
-          moduleNode.id = moduleId
-          moduleNode.transformResult = {
-            code: ' ',
-            map: null,
-          }
-          environment.moduleGraph.idToModuleMap.set(moduleId, moduleNode)
-          nodesById.set(moduleId, moduleNode)
-        })
+        restoreAndWireEnvironmentModuleGraph(environment, moduleGraph)
       })
 
-      Object.entries(environments).forEach(([environmentName, moduleGraph]) => {
-        const nodesById = createdByEnvironment.get(environmentName)
-        if (!nodesById) {
-          return
-        }
+      const browserModuleGraph = modulesByProject.browser
+      if (!browserModuleGraph) {
+        return
+      }
 
-        moduleGraph.modules.forEach(([id, _file, _url, importedIds]) => {
-          const moduleId = moduleGraph.idTable[id]
-          if (!moduleId) {
-            return
-          }
-          const moduleNode = nodesById.get(moduleId)
-          if (!moduleNode) {
-            return
-          }
-          importedIds.forEach((importedIdIndex) => {
-            const importedId = moduleGraph.idTable[importedIdIndex]
-            if (!importedId) {
-              return
-            }
-            const importedNode = nodesById.get(importedId)
-            if (!importedNode) {
-              return
-            }
-            moduleNode.importedModules.add(importedNode)
-            importedNode.importers.add(moduleNode)
-          })
-        })
-      })
+      // TODO: how to restore project.browser?
+      const browserEnvironment = project.browser?.vite.environments.client
+      const fallbackEnvironment = project.vite.environments.client
+      const targetEnvironment = browserEnvironment || fallbackEnvironment
+      if (!targetEnvironment) {
+        return
+      }
+
+      restoreAndWireEnvironmentModuleGraph(targetEnvironment, browserModuleGraph)
     })
   })
 
@@ -305,25 +229,135 @@ type MergeReport = [
   coverage: unknown,
   executionTime: number,
   environmentModules: MergeReportEnvironmentModules,
-  externalized: SerializedExternalizedByProject,
 ]
 
 interface MergeReportEnvironmentModules {
   [projectName: string]: {
-    [environmentName: string]: {
-      idTable: string[]
-      modules: SerializedEnvironmentModuleNode[]
+    environments: {
+      [environmentName: string]: SerializedEnvironmentModuleGraph
     }
+    browser?: SerializedEnvironmentModuleGraph
+    external: [id: string, externalized: string][]
   }
 }
 
-interface SerializedExternalizedByProject {
-  [projectName: string]: [id: string, externalized: string][]
-}
-
 type SerializedEnvironmentModuleNode = [
   id: number,
   file: number,
   url: number,
   importedIds: number[],
 ]
+
+interface SerializedEnvironmentModuleGraph {
+  idTable: string[]
+  modules: SerializedEnvironmentModuleNode[]
+}
+
+function serializeEnvironmentModuleGraph(
+  environment: DevEnvironment,
+): SerializedEnvironmentModuleGraph {
+  const idTable: string[] = []
+  const idMap = new Map<string, number>()
+
+  const getIdIndex = (id: string) => {
+    const existing = idMap.get(id)
+    if (existing != null) {
+      return existing
+    }
+    const next = idTable.length
+    idMap.set(id, next)
+    idTable.push(id)
+    return next
+  }
+
+  const modules: SerializedEnvironmentModuleNode[] = []
+  for (const [id, mod] of environment.moduleGraph.idToModuleMap.entries()) {
+    if (!mod.file) {
+      continue
+    }
+
+    const importedIds: number[] = []
+    for (const importedNode of mod.importedModules) {
+      if (importedNode.id) {
+        importedIds.push(getIdIndex(importedNode.id))
+      }
+    }
+
+    modules.push([
+      getIdIndex(id),
+      getIdIndex(mod.file),
+      getIdIndex(mod.url),
+      importedIds,
+    ])
+  }
+
+  return {
+    idTable,
+    modules,
+  }
+}
+
+function restoreEnvironmentModuleGraph(
+  environment: DevEnvironment,
+  serialized: SerializedEnvironmentModuleGraph,
+): Map<string, EnvironmentModuleNode> {
+  const nodesById = new Map<string, EnvironmentModuleNode>()
+
+  serialized.modules.forEach(([id, file, url]) => {
+    const moduleId = serialized.idTable[id]
+    const filePath = serialized.idTable[file]
+    const urlPath = serialized.idTable[url]
+    if (!moduleId || !filePath || !urlPath) {
+      return
+    }
+    const moduleNode = environment.moduleGraph.createFileOnlyEntry(filePath)
+    moduleNode.url = urlPath
+    moduleNode.id = moduleId
+    moduleNode.transformResult = {
+      code: ' ',
+      map: null,
+    }
+    environment.moduleGraph.idToModuleMap.set(moduleId, moduleNode)
+    nodesById.set(moduleId, moduleNode)
+  })
+
+  return nodesById
+}
+
+function restoreAndWireEnvironmentModuleGraph(
+  environment: DevEnvironment,
+  serialized: SerializedEnvironmentModuleGraph,
+): void {
+  wireEnvironmentModuleGraph(
+    restoreEnvironmentModuleGraph(environment, serialized),
+    serialized,
+  )
+}
+
+function wireEnvironmentModuleGraph(
+  nodesById: Map<string, EnvironmentModuleNode>,
+  serialized: SerializedEnvironmentModuleGraph,
+): void {
+  serialized.modules.forEach(([id, _file, _url, importedIds]) => {
+    const moduleId = serialized.idTable[id]
+    if (!moduleId) {
+      return
+    }
+    const moduleNode = nodesById.get(moduleId)
+    if (!moduleNode) {
+      return
+    }
+    importedIds.forEach((importedIdIndex) => {
+      const importedId = serialized.idTable[importedIdIndex]
+      if (!importedId) {
+        return
+      }
+      const importedNode = nodesById.get(importedId)
+      if (!importedNode) {
+        return
+      }
+      moduleNode.importedModules.add(importedNode)
+      importedNode.importers.add(moduleNode)
+    })
+  })
+}
diff --git a/test/cli/test/reporters/merge-reports.test.ts b/test/cli/test/reporters/merge-reports.test.ts
index 6b2cf56410aa..24d4c3448710 100644
--- a/test/cli/test/reporters/merge-reports.test.ts
+++ b/test/cli/test/reporters/merge-reports.test.ts
@@ -256,7 +256,7 @@ test('total and merged execution times are shown', async () => {
     file.tasks.push(createTest('some test', file))
 
     await writeBlob(
-      [version, [file], [], undefined, 1500 * index, {}, {}],
+      [version, [file], [], undefined, 1500 * index, {}],
       resolve(`./fixtures/reporters/merge-reports/.vitest-reports/blob-${index}-2.json`),
     )
   }
@@ -280,7 +280,7 @@ test('module graph available', async () => {
   rmSync(reportsDir, { force: true, recursive: true })
 
   async function getSerializedModuleGraph(ctx: Vitest) {
-    const files = ctx.state.getFiles().slice().sort()
+    const files = ctx.state.getFiles().slice().sort((a, b) => a.filepath.localeCompare(b.filepath))
     const moduleGraphs = Object.fromEntries(
       await Promise.all(
         files.map(async (file) => {

From 9e0572d7b959daf7d9d7ff6aabe5373f1622e0ec Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 17:53:49 +0900
Subject: [PATCH 08/15] refactor: minor

---
 packages/vitest/src/node/reporters/blob.ts | 21 ++-------------------
 1 file changed, 2 insertions(+), 19 deletions(-)

diff --git a/packages/vitest/src/node/reporters/blob.ts b/packages/vitest/src/node/reporters/blob.ts
index ffc7d4fbe443..b14b87e5cb02 100644
--- a/packages/vitest/src/node/reporters/blob.ts
+++ b/packages/vitest/src/node/reporters/blob.ts
@@ -297,10 +297,10 @@ function serializeEnvironmentModuleGraph(
   }
 }
 
-function restoreEnvironmentModuleGraph(
+function restoreAndWireEnvironmentModuleGraph(
   environment: DevEnvironment,
   serialized: SerializedEnvironmentModuleGraph,
-): Map<string, EnvironmentModuleNode> {
+): void {
   const nodesById = new Map<string, EnvironmentModuleNode>()
 
   serialized.modules.forEach(([id, file, url]) => {
@@ -321,23 +321,6 @@ function restoreEnvironmentModuleGraph(
     nodesById.set(moduleId, moduleNode)
   })
 
-  return nodesById
-}
-
-function restoreAndWireEnvironmentModuleGraph(
-  environment: DevEnvironment,
-  serialized: SerializedEnvironmentModuleGraph,
-): void {
-  wireEnvironmentModuleGraph(
-    restoreEnvironmentModuleGraph(environment, serialized),
-    serialized,
-  )
-}
-
-function wireEnvironmentModuleGraph(
-  nodesById: Map<string, EnvironmentModuleNode>,
-  serialized: SerializedEnvironmentModuleGraph,
-): void {
   serialized.modules.forEach(([id, _file, _url, importedIds]) => {
     const moduleId = serialized.idTable[id]
     if (!moduleId) {

From 1684a9c7444f88c375d9b1fa778e33de6506f38d Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 19:03:24 +0900
Subject: [PATCH 09/15] test: fix windows

---
 test/cli/test/reporters/merge-reports.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/cli/test/reporters/merge-reports.test.ts b/test/cli/test/reporters/merge-reports.test.ts
index 24d4c3448710..f34d1f489d44 100644
--- a/test/cli/test/reporters/merge-reports.test.ts
+++ b/test/cli/test/reporters/merge-reports.test.ts
@@ -298,7 +298,7 @@ test('module graph available', async () => {
     )
     return JSON.stringify(moduleGraphs, null, 2)
       .replaceAll(ctx.config.root, '<root>')
-      .replace(/"\/[^"\n]*\/node_modules\//g, '"<node_modules>/')
+      .replace(/"[^"\n]*\/node_modules\//g, '"<node_modules>/')
   }
 
   // generate blob

From 27e2798c70feab64e3ef22acaff83e6a146eed0f Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 19:19:46 +0900
Subject: [PATCH 10/15] fix: restore browser mode

---
 packages/vitest/src/node/reporters/blob.ts | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/packages/vitest/src/node/reporters/blob.ts b/packages/vitest/src/node/reporters/blob.ts
index b14b87e5cb02..393c5c2930ec 100644
--- a/packages/vitest/src/node/reporters/blob.ts
+++ b/packages/vitest/src/node/reporters/blob.ts
@@ -163,6 +163,12 @@ export async function readBlobs(
     projectsArray.map(p => [p.name, p]),
   )
 
+  for (const project of projectsArray) {
+    if (project.isBrowserEnabled()) {
+      await project._initBrowserServer()
+    }
+  }
+
   blobs.forEach((blob) => {
     Object.entries(blob.environmentModules).forEach(([projectName, modulesByProject]) => {
       const project = projects[projectName]
@@ -183,16 +189,11 @@ export async function readBlobs(
       if (!browserModuleGraph) {
         return
       }
-
-      // TODO: how to restore project.browser?
       const browserEnvironment = project.browser?.vite.environments.client
-      const fallbackEnvironment = project.vite.environments.client
-      const targetEnvironment = browserEnvironment || fallbackEnvironment
-      if (!targetEnvironment) {
-        return
+      if (!browserEnvironment) {
+        throw new Error(`Cannot find browser environment for project "${projectName}" while restoring module graph in merge mode`)
       }
-
-      restoreAndWireEnvironmentModuleGraph(targetEnvironment, browserModuleGraph)
+      restoreAndWireEnvironmentModuleGraph(browserEnvironment, browserModuleGraph)
     })
   })
 

From 65092ab0dd6905791efec24f1ebb05b94cb4e954 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 19:21:46 +0900
Subject: [PATCH 11/15] refactor: minor

---
 packages/vitest/src/node/reporters/blob.ts | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/packages/vitest/src/node/reporters/blob.ts b/packages/vitest/src/node/reporters/blob.ts
index 393c5c2930ec..d6efc5a7f56d 100644
--- a/packages/vitest/src/node/reporters/blob.ts
+++ b/packages/vitest/src/node/reporters/blob.ts
@@ -182,18 +182,14 @@ export async function readBlobs(
 
       Object.entries(modulesByProject.environments).forEach(([environmentName, moduleGraph]) => {
         const environment = project.vite.environments[environmentName]
-        restoreAndWireEnvironmentModuleGraph(environment, moduleGraph)
+        deserializeEnvironmentModuleGraph(environment, moduleGraph)
       })
 
       const browserModuleGraph = modulesByProject.browser
-      if (!browserModuleGraph) {
-        return
-      }
-      const browserEnvironment = project.browser?.vite.environments.client
-      if (!browserEnvironment) {
-        throw new Error(`Cannot find browser environment for project "${projectName}" while restoring module graph in merge mode`)
+      if (browserModuleGraph) {
+        const browserEnvironment = project.browser!.vite.environments.client
+        deserializeEnvironmentModuleGraph(browserEnvironment, browserModuleGraph)
       }
-      restoreAndWireEnvironmentModuleGraph(browserEnvironment, browserModuleGraph)
     })
   })
 
@@ -298,7 +294,7 @@ function serializeEnvironmentModuleGraph(
   }
 }
 
-function restoreAndWireEnvironmentModuleGraph(
+function deserializeEnvironmentModuleGraph(
   environment: DevEnvironment,
   serialized: SerializedEnvironmentModuleGraph,
 ): void {

From a0036d1318ea6521ebe7b7cea1a7445016061f67 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 19:22:59 +0900
Subject: [PATCH 12/15] refactor: minor

---
 packages/vitest/src/node/resolver.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/vitest/src/node/resolver.ts b/packages/vitest/src/node/resolver.ts
index 658aa4ea5b93..94670766646d 100644
--- a/packages/vitest/src/node/resolver.ts
+++ b/packages/vitest/src/node/resolver.ts
@@ -12,7 +12,7 @@ import { isWindows } from '../utils/env'
 export class VitestResolver {
   public readonly options: ExternalizeOptions
   private externalizeConcurrentCache = new Map<string, Promise<string | false | undefined>>()
-  public externalizeCache: Map<string, string | false | undefined> = new Map<string, string | false | undefined>()
+  public externalizeCache: Map<string, string | false | undefined> = new Map()
 
   constructor(cacheDir: string, config: ResolvedConfig) {
     // sorting to make cache consistent

From e47b727d50be9fd88c60d45f792f457bfa96e5f3 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 19:35:45 +0900
Subject: [PATCH 13/15] test: wip

---
 .../vitest.config.js                          |   4 +-
 test/cli/test/reporters/merge-reports.test.ts | 142 ++++++++++++++++++
 2 files changed, 145 insertions(+), 1 deletion(-)

diff --git a/test/cli/fixtures/reporters/merge-reports-module-graph/vitest.config.js b/test/cli/fixtures/reporters/merge-reports-module-graph/vitest.config.js
index b1c6ea436a54..94a64e2f78ac 100644
--- a/test/cli/fixtures/reporters/merge-reports-module-graph/vitest.config.js
+++ b/test/cli/fixtures/reporters/merge-reports-module-graph/vitest.config.js
@@ -1 +1,3 @@
-export default {}
+import { defineConfig } from "vitest/config"
+
+export default defineConfig({})
diff --git a/test/cli/test/reporters/merge-reports.test.ts b/test/cli/test/reporters/merge-reports.test.ts
index f34d1f489d44..bc7e578d0ba4 100644
--- a/test/cli/test/reporters/merge-reports.test.ts
+++ b/test/cli/test/reporters/merge-reports.test.ts
@@ -8,6 +8,7 @@ import { beforeEach, expect, test } from 'vitest'
 import { version } from 'vitest/package.json'
 import { writeBlob } from 'vitest/src/node/reporters/blob.js'
 import { getModuleGraph } from '../../../../packages/vitest/src/utils/graph'
+import { playwright } from '@vitest/browser-playwright'
 
 // always relative to CWD because it's used only from the CLI,
 // so we need to correctly resolve it here
@@ -299,6 +300,8 @@ test('module graph available', async () => {
     return JSON.stringify(moduleGraphs, null, 2)
       .replaceAll(ctx.config.root, '<root>')
       .replace(/"[^"\n]*\/node_modules\//g, '"<node_modules>/')
+      .replace(/<node_modules>\/\.vite\/vitest\/[a-f0-9]{40}\/deps\/([^"?]+)/g, '<optimized-deps>/$1')
+      .replace(/\?v=[a-f0-9]+/g, '?v=<hash>')
   }
 
   // generate blob
@@ -379,6 +382,145 @@ test('module graph available', async () => {
   `)
 })
 
+
+
+test('module graph available', async () => {
+  const root = resolve('./fixtures/reporters/merge-reports-module-graph')
+  const reportsDir = resolve(root, '.vitest-reports')
+  rmSync(reportsDir, { force: true, recursive: true })
+
+  async function getSerializedModuleGraph(ctx: Vitest) {
+    const files = ctx.state.getFiles().slice().sort((a, b) => a.filepath.localeCompare(b.filepath))
+    const moduleGraphs = Object.fromEntries(
+      await Promise.all(
+        files.map(async (file) => {
+          const projectName = file.projectName || ''
+          const project = ctx.getProjectByName(projectName)
+          const graph = await getModuleGraph(
+            ctx,
+            projectName,
+            file.filepath,
+            project.config.browser.enabled,
+          )
+          return [file.filepath, graph] as const
+        }),
+      ),
+    )
+    return JSON.stringify(moduleGraphs, null, 2)
+      .replaceAll(ctx.config.root, '<root>')
+      .replace(/"[^"\n]*\/node_modules\//g, '"<node_modules>/')
+      .replace(/<node_modules>\/\.vite\/vitest\/[a-f0-9]*\/deps\/([^"?]+)/g, '<optimized-deps>/$1')
+      .replace(/\?v=[a-f0-9]+/g, '?v=<hash>')
+  }
+
+  // generate blob
+  const result = await runVitest({
+    root,
+    reporters: ['blob'],
+    browser: {
+      enabled: true,
+      provider: playwright(),
+      instances: [
+        {
+          browser: 'chromium',
+        }
+      ],
+      headless: true,
+    }
+  })
+  expect.assert(result.ctx)
+  const generatedModuleGraphJson = await getSerializedModuleGraph(result.ctx)
+  expect(generatedModuleGraphJson).toMatchInlineSnapshot(`
+    "{
+      "<root>/basic.test.ts": {
+        "graph": {
+          "<root>/sub/subject.ts": [],
+          "<root>/sub/format.ts": [
+            "<root>/sub/subject.ts"
+          ],
+          "<root>/util.ts": [
+            "<root>/sub/subject.ts"
+          ],
+          "<root>/basic.test.ts": [
+            "<root>/sub/format.ts",
+            "<root>/util.ts"
+          ]
+        },
+        "externalized": [],
+        "inlined": [
+          "<root>/basic.test.ts",
+          "<root>/sub/format.ts",
+          "<root>/sub/subject.ts",
+          "<root>/util.ts"
+        ]
+      },
+      "<root>/second.test.ts": {
+        "graph": {
+          "<root>/sub/subject.ts": [],
+          "<root>/util.ts": [
+            "<root>/sub/subject.ts"
+          ],
+          "<root>/second.test.ts": [
+            "<root>/util.ts",
+            "<optimized-deps>/obug.js"
+          ]
+        },
+        "externalized": [
+          "<optimized-deps>/obug.js?v=<hash>"
+        ],
+        "inlined": [
+          "<root>/second.test.ts",
+          "<root>/util.ts",
+          "<root>/sub/subject.ts"
+        ]
+      }
+    }"
+  `)
+
+  // test restored blob has module graph
+  const result2 = await runVitest({
+    root,
+    mergeReports: reportsDir,
+    browser: {
+      enabled: true,
+      provider: playwright(),
+      instances: [
+        {
+          browser: 'chromium',
+        }
+      ],
+      headless: true,
+    }
+  })
+  expect(result2.stderr).toMatchInlineSnapshot(`""`)
+  expect.assert(result2.ctx)
+  const restoredModuleGraphJson = await getSerializedModuleGraph(result2.ctx)
+  expect(restoredModuleGraphJson).toBe(generatedModuleGraphJson)
+
+  // also check html reporter doesn't crash
+  const result3 = await runVitest({
+    root,
+    mergeReports: resolve(root, '.vitest-reports'),
+    reporters: ['html'],
+    browser: {
+      enabled: true,
+      provider: playwright(),
+      instances: [
+        {
+          browser: 'chromium',
+        }
+      ],
+      headless: true,
+    }
+  })
+  expect(result3.stderr).toMatchInlineSnapshot(`""`)
+  expect(result3.stdout).toMatchInlineSnapshot(`
+    " HTML  Report is generated
+           You can run npx vite preview --outDir html to see the test results.
+    "
+  `)
+})
+
 function trimReporterOutput(report: string) {
   const rows = report
     .replace(/\d+ms/g, '<time>')

From 721bb7e79040316abc973a3eb1deb8f26a1c28d3 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 19:40:53 +0900
Subject: [PATCH 14/15] test: refactor

---
 test/cli/test/reporters/merge-reports.test.ts | 329 +++++++-----------
 1 file changed, 128 insertions(+), 201 deletions(-)

diff --git a/test/cli/test/reporters/merge-reports.test.ts b/test/cli/test/reporters/merge-reports.test.ts
index bc7e578d0ba4..2f445b5c20f9 100644
--- a/test/cli/test/reporters/merge-reports.test.ts
+++ b/test/cli/test/reporters/merge-reports.test.ts
@@ -1,14 +1,14 @@
 import type { File, Test } from '@vitest/runner/types'
-import type { Vitest } from 'vitest/node'
+import type { TestUserConfig, Vitest } from 'vitest/node'
 import { rmSync } from 'node:fs'
 import { resolve } from 'node:path'
 import { runVitest } from '#test-utils'
+import { playwright } from '@vitest/browser-playwright'
 import { createFileTask } from '@vitest/runner/utils'
 import { beforeEach, expect, test } from 'vitest'
 import { version } from 'vitest/package.json'
 import { writeBlob } from 'vitest/src/node/reporters/blob.js'
 import { getModuleGraph } from '../../../../packages/vitest/src/utils/graph'
-import { playwright } from '@vitest/browser-playwright'
 
 // always relative to CWD because it's used only from the CLI,
 // so we need to correctly resolve it here
@@ -275,243 +275,146 @@ test('total and merged execution times are shown', async () => {
   expect(stdout).toContain('Per blob  1.50s 3.00s')
 })
 
-test('module graph available', async () => {
+test.for([
+  'node',
+  'browser',
+])('module graph and html reporter $0', async (mode) => {
   const root = resolve('./fixtures/reporters/merge-reports-module-graph')
   const reportsDir = resolve(root, '.vitest-reports')
   rmSync(reportsDir, { force: true, recursive: true })
 
-  async function getSerializedModuleGraph(ctx: Vitest) {
-    const files = ctx.state.getFiles().slice().sort((a, b) => a.filepath.localeCompare(b.filepath))
-    const moduleGraphs = Object.fromEntries(
-      await Promise.all(
-        files.map(async (file) => {
-          const projectName = file.projectName || ''
-          const project = ctx.getProjectByName(projectName)
-          const graph = await getModuleGraph(
-            ctx,
-            projectName,
-            file.filepath,
-            project.config.browser.enabled,
-          )
-          return [file.filepath, graph] as const
-        }),
-      ),
-    )
-    return JSON.stringify(moduleGraphs, null, 2)
-      .replaceAll(ctx.config.root, '<root>')
-      .replace(/"[^"\n]*\/node_modules\//g, '"<node_modules>/')
-      .replace(/<node_modules>\/\.vite\/vitest\/[a-f0-9]{40}\/deps\/([^"?]+)/g, '<optimized-deps>/$1')
-      .replace(/\?v=[a-f0-9]+/g, '?v=<hash>')
-  }
-
-  // generate blob
-  const result = await runVitest({
+  const baseConfig: TestUserConfig = {
     root,
-    reporters: ['blob'],
-  })
-  expect.assert(result.ctx)
-  const generatedModuleGraphJson = await getSerializedModuleGraph(result.ctx)
-  expect(generatedModuleGraphJson).toMatchInlineSnapshot(`
-    "{
-      "<root>/basic.test.ts": {
-        "graph": {
-          "<root>/sub/subject.ts": [],
-          "<root>/sub/format.ts": [
-            "<root>/sub/subject.ts"
-          ],
-          "<root>/util.ts": [
-            "<root>/sub/subject.ts"
-          ],
-          "<root>/basic.test.ts": [
-            "<root>/sub/format.ts",
-            "<root>/util.ts"
-          ]
-        },
-        "externalized": [],
-        "inlined": [
-          "<root>/basic.test.ts",
-          "<root>/sub/format.ts",
-          "<root>/sub/subject.ts",
-          "<root>/util.ts"
-        ]
-      },
-      "<root>/second.test.ts": {
-        "graph": {
-          "<root>/sub/subject.ts": [],
-          "<root>/util.ts": [
-            "<root>/sub/subject.ts"
-          ],
-          "<root>/second.test.ts": [
-            "<root>/util.ts",
-            "<node_modules>/obug/dist/node.js"
-          ]
-        },
-        "externalized": [
-          "<node_modules>/obug/dist/node.js"
-        ],
-        "inlined": [
-          "<root>/second.test.ts",
-          "<root>/util.ts",
-          "<root>/sub/subject.ts"
-        ]
-      }
-    }"
-  `)
-
-  // test restored blob has module graph
-  const result2 = await runVitest({
-    root,
-    mergeReports: reportsDir,
-  })
-  expect(result2.stderr).toMatchInlineSnapshot(`""`)
-  expect.assert(result2.ctx)
-  const restoredModuleGraphJson = await getSerializedModuleGraph(result2.ctx)
-  expect(restoredModuleGraphJson).toBe(generatedModuleGraphJson)
-
-  // also check html reporter doesn't crash
-  const result3 = await runVitest({
-    root,
-    mergeReports: resolve(root, '.vitest-reports'),
-    reporters: ['html'],
-  })
-  expect(result3.stderr).toMatchInlineSnapshot(`""`)
-  expect(result3.stdout).toMatchInlineSnapshot(`
-    " HTML  Report is generated
-           You can run npx vite preview --outDir html to see the test results.
-    "
-  `)
-})
-
-
-
-test('module graph available', async () => {
-  const root = resolve('./fixtures/reporters/merge-reports-module-graph')
-  const reportsDir = resolve(root, '.vitest-reports')
-  rmSync(reportsDir, { force: true, recursive: true })
-
-  async function getSerializedModuleGraph(ctx: Vitest) {
-    const files = ctx.state.getFiles().slice().sort((a, b) => a.filepath.localeCompare(b.filepath))
-    const moduleGraphs = Object.fromEntries(
-      await Promise.all(
-        files.map(async (file) => {
-          const projectName = file.projectName || ''
-          const project = ctx.getProjectByName(projectName)
-          const graph = await getModuleGraph(
-            ctx,
-            projectName,
-            file.filepath,
-            project.config.browser.enabled,
-          )
-          return [file.filepath, graph] as const
-        }),
-      ),
-    )
-    return JSON.stringify(moduleGraphs, null, 2)
-      .replaceAll(ctx.config.root, '<root>')
-      .replace(/"[^"\n]*\/node_modules\//g, '"<node_modules>/')
-      .replace(/<node_modules>\/\.vite\/vitest\/[a-f0-9]*\/deps\/([^"?]+)/g, '<optimized-deps>/$1')
-      .replace(/\?v=[a-f0-9]+/g, '?v=<hash>')
   }
-
-  // generate blob
-  const result = await runVitest({
-    root,
-    reporters: ['blob'],
-    browser: {
+  if (mode === 'browser') {
+    baseConfig.browser = {
       enabled: true,
       provider: playwright(),
       instances: [
         {
           browser: 'chromium',
-        }
+        },
       ],
       headless: true,
     }
+  }
+
+  const result = await runVitest({
+    ...baseConfig,
+    reporters: ['blob'],
   })
   expect.assert(result.ctx)
   const generatedModuleGraphJson = await getSerializedModuleGraph(result.ctx)
-  expect(generatedModuleGraphJson).toMatchInlineSnapshot(`
-    "{
-      "<root>/basic.test.ts": {
-        "graph": {
-          "<root>/sub/subject.ts": [],
-          "<root>/sub/format.ts": [
-            "<root>/sub/subject.ts"
+  if (mode === 'browser') {
+    expect(generatedModuleGraphJson).toMatchInlineSnapshot(`
+      "{
+        "<root>/basic.test.ts": {
+          "graph": {
+            "<root>/sub/subject.ts": [],
+            "<root>/sub/format.ts": [
+              "<root>/sub/subject.ts"
+            ],
+            "<root>/util.ts": [
+              "<root>/sub/subject.ts"
+            ],
+            "<root>/basic.test.ts": [
+              "<root>/sub/format.ts",
+              "<root>/util.ts"
+            ]
+          },
+          "externalized": [],
+          "inlined": [
+            "<root>/basic.test.ts",
+            "<root>/sub/format.ts",
+            "<root>/sub/subject.ts",
+            "<root>/util.ts"
+          ]
+        },
+        "<root>/second.test.ts": {
+          "graph": {
+            "<root>/sub/subject.ts": [],
+            "<root>/util.ts": [
+              "<root>/sub/subject.ts"
+            ],
+            "<root>/second.test.ts": [
+              "<root>/util.ts",
+              "<optimized-deps>/obug.js"
+            ]
+          },
+          "externalized": [
+            "<optimized-deps>/obug.js?v=<hash>"
           ],
-          "<root>/util.ts": [
+          "inlined": [
+            "<root>/second.test.ts",
+            "<root>/util.ts",
             "<root>/sub/subject.ts"
-          ],
-          "<root>/basic.test.ts": [
+          ]
+        }
+      }"
+    `)
+  }
+  else {
+    expect(generatedModuleGraphJson).toMatchInlineSnapshot(`
+      "{
+        "<root>/basic.test.ts": {
+          "graph": {
+            "<root>/sub/subject.ts": [],
+            "<root>/sub/format.ts": [
+              "<root>/sub/subject.ts"
+            ],
+            "<root>/util.ts": [
+              "<root>/sub/subject.ts"
+            ],
+            "<root>/basic.test.ts": [
+              "<root>/sub/format.ts",
+              "<root>/util.ts"
+            ]
+          },
+          "externalized": [],
+          "inlined": [
+            "<root>/basic.test.ts",
             "<root>/sub/format.ts",
+            "<root>/sub/subject.ts",
             "<root>/util.ts"
           ]
         },
-        "externalized": [],
-        "inlined": [
-          "<root>/basic.test.ts",
-          "<root>/sub/format.ts",
-          "<root>/sub/subject.ts",
-          "<root>/util.ts"
-        ]
-      },
-      "<root>/second.test.ts": {
-        "graph": {
-          "<root>/sub/subject.ts": [],
-          "<root>/util.ts": [
-            "<root>/sub/subject.ts"
+        "<root>/second.test.ts": {
+          "graph": {
+            "<root>/sub/subject.ts": [],
+            "<root>/util.ts": [
+              "<root>/sub/subject.ts"
+            ],
+            "<root>/second.test.ts": [
+              "<root>/util.ts",
+              "<node_modules>/obug/dist/node.js"
+            ]
+          },
+          "externalized": [
+            "<node_modules>/obug/dist/node.js"
           ],
-          "<root>/second.test.ts": [
+          "inlined": [
+            "<root>/second.test.ts",
             "<root>/util.ts",
-            "<optimized-deps>/obug.js"
+            "<root>/sub/subject.ts"
           ]
-        },
-        "externalized": [
-          "<optimized-deps>/obug.js?v=<hash>"
-        ],
-        "inlined": [
-          "<root>/second.test.ts",
-          "<root>/util.ts",
-          "<root>/sub/subject.ts"
-        ]
-      }
-    }"
-  `)
+        }
+      }"
+    `)
+  }
 
-  // test restored blob has module graph
   const result2 = await runVitest({
-    root,
+    ...baseConfig,
     mergeReports: reportsDir,
-    browser: {
-      enabled: true,
-      provider: playwright(),
-      instances: [
-        {
-          browser: 'chromium',
-        }
-      ],
-      headless: true,
-    }
   })
   expect(result2.stderr).toMatchInlineSnapshot(`""`)
   expect.assert(result2.ctx)
   const restoredModuleGraphJson = await getSerializedModuleGraph(result2.ctx)
   expect(restoredModuleGraphJson).toBe(generatedModuleGraphJson)
 
-  // also check html reporter doesn't crash
   const result3 = await runVitest({
-    root,
+    ...baseConfig,
     mergeReports: resolve(root, '.vitest-reports'),
     reporters: ['html'],
-    browser: {
-      enabled: true,
-      provider: playwright(),
-      instances: [
-        {
-          browser: 'chromium',
-        }
-      ],
-      headless: true,
-    }
   })
   expect(result3.stderr).toMatchInlineSnapshot(`""`)
   expect(result3.stdout).toMatchInlineSnapshot(`
@@ -521,6 +424,30 @@ test('module graph available', async () => {
   `)
 })
 
+async function getSerializedModuleGraph(ctx: Vitest) {
+  const files = ctx.state.getFiles().slice().sort((a, b) => a.filepath.localeCompare(b.filepath))
+  const moduleGraphs = Object.fromEntries(
+    await Promise.all(
+      files.map(async (file) => {
+        const projectName = file.projectName || ''
+        const project = ctx.getProjectByName(projectName)
+        const graph = await getModuleGraph(
+          ctx,
+          projectName,
+          file.filepath,
+          project.config.browser.enabled,
+        )
+        return [file.filepath, graph] as const
+      }),
+    ),
+  )
+  return JSON.stringify(moduleGraphs, null, 2)
+    .replaceAll(ctx.config.root, '<root>')
+    .replace(/"[^"\n]*\/node_modules\//g, '"<node_modules>/')
+    .replace(/<node_modules>\/\.vite\/vitest\/[a-f0-9]{40}\/deps\/([^"?]+)/g, '<optimized-deps>/$1')
+    .replace(/\?v=[a-f0-9]+/g, '?v=<hash>')
+}
+
 function trimReporterOutput(report: string) {
   const rows = report
     .replace(/\d+ms/g, '<time>')

From 94540d3e5a3688df022eaf0d879fc1d600451db4 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 25 Feb 2026 19:56:43 +0900
Subject: [PATCH 15/15] refactor: minor

---
 packages/vitest/src/node/reporters/blob.ts | 23 ++++------------------
 1 file changed, 4 insertions(+), 19 deletions(-)

diff --git a/packages/vitest/src/node/reporters/blob.ts b/packages/vitest/src/node/reporters/blob.ts
index d6efc5a7f56d..32dd65948bd7 100644
--- a/packages/vitest/src/node/reporters/blob.ts
+++ b/packages/vitest/src/node/reporters/blob.ts
@@ -157,8 +157,7 @@ export async function readBlobs(
     )
   }
 
-  // Restore per-environment module graphs so merge mode can reuse
-  // the same module graph based flows as regular test runs.
+  // Restore module graph
   const projects = Object.fromEntries(
     projectsArray.map(p => [p.name, p]),
   )
@@ -304,13 +303,11 @@ function deserializeEnvironmentModuleGraph(
     const moduleId = serialized.idTable[id]
     const filePath = serialized.idTable[file]
     const urlPath = serialized.idTable[url]
-    if (!moduleId || !filePath || !urlPath) {
-      return
-    }
     const moduleNode = environment.moduleGraph.createFileOnlyEntry(filePath)
     moduleNode.url = urlPath
     moduleNode.id = moduleId
     moduleNode.transformResult = {
+      // print error checks that transformResult is set
       code: ' ',
       map: null,
     }
@@ -320,22 +317,10 @@ function deserializeEnvironmentModuleGraph(
 
   serialized.modules.forEach(([id, _file, _url, importedIds]) => {
     const moduleId = serialized.idTable[id]
-    if (!moduleId) {
-      return
-    }
-    const moduleNode = nodesById.get(moduleId)
-    if (!moduleNode) {
-      return
-    }
+    const moduleNode = nodesById.get(moduleId)!
     importedIds.forEach((importedIdIndex) => {
       const importedId = serialized.idTable[importedIdIndex]
-      if (!importedId) {
-        return
-      }
-      const importedNode = nodesById.get(importedId)
-      if (!importedNode) {
-        return
-      }
+      const importedNode = nodesById.get(importedId)!
       moduleNode.importedModules.add(importedNode)
       importedNode.importers.add(moduleNode)
     })