fix(gatsby): Allow "gatsby-node" directory for Parcel Compilation

packages/gatsby-cli/src/structured-errors/error-map.ts

@@ -358,9 +358,9 @@ const errors = {
   },
   "10124": {
     text: (context): string =>
-      `It looks like you were trying to add the config file? Please rename "${
-        context.nearMatch
-      }" to "${context.configName}.${context.isTSX ? `ts` : `js`}"`,
+      ` the config file? Please rename "${context.nearMatch}" to "${
+        context.configName
+      }.${context.isTSX ? `ts` : `js`}"`,
     type: Type.CONFIG,
     level: Level.ERROR,
     category: ErrorCategory.USER,

packages/gatsby/src/utils/parcel/__tests__/compile-gatsby-files.ts

@@ -17,6 +17,7 @@ const dir = {
   tsOnlyInLocal: `${__dirname}/fixtures/ts-only-in-local-plugin`,
   misnamedJS: `${__dirname}/fixtures/misnamed-js`,
   misnamedTS: `${__dirname}/fixtures/misnamed-ts`,
+  gatsbyNode: `${__dirname}/fixtures/gatsby-node`,
 }
 
 jest.setTimeout(15000)
@@ -173,6 +174,30 @@ describe(`gatsby file compilation`, () => {
   })
 })
 
+describe(`gatsby-node directory is allowed`, () => {
+  beforeEach(() => {
+    reporterPanicMock.mockClear()
+  })
+  it(`should not panic on gatsby-node dir`, async () => {
+    process.chdir(dir.gatsbyNode)
+    await remove(`${dir.gatsbyNode}/.cache`)
+    await compileGatsbyFiles(dir.gatsbyNode)
+
+    expect(reporterPanicMock).not.toHaveBeenCalled()
+  })
+
+  it(`should not compile gatsby-node dir`, async () => {
+    process.chdir(dir.gatsbyNode)
+    await remove(`${dir.gatsbyNode}/.cache`)
+    await compileGatsbyFiles(dir.gatsbyNode)
+    const isCompiled = await pathExists(
+      `${dir.gatsbyNode}/.cache/compiled/gatsby-node`
+    )
+    expect(isCompiled).toEqual(false)
+    expect(reporterPanicMock).not.toHaveBeenCalled()
+  })
+})
+
 describe(`misnamed gatsby-node files`, () => {
   beforeEach(() => {
     reporterPanicMock.mockClear()

packages/gatsby/src/utils/parcel/__tests__/fixtures/gatsby-node/createPages.js

@@ -0,0 +1,3 @@
+export default createPages() {
+    console.log('createPages!');
+}

packages/gatsby/src/utils/parcel/compile-gatsby-files.ts

@@ -3,7 +3,14 @@ import { LMDBCache, Cache } from "@parcel/cache"
 import path from "path"
 import type { Diagnostic } from "@parcel/diagnostic"
 import reporter from "gatsby-cli/lib/reporter"
-import { ensureDir, emptyDir, existsSync, remove, readdir } from "fs-extra"
+import {
+  ensureDir,
+  emptyDir,
+  existsSync,
+  remove,
+  readdir,
+  lstat,
+} from "fs-extra"
 import telemetry from "gatsby-telemetry"
 import { isNearMatch } from "../is-near-match"
 
@@ -61,24 +68,36 @@ export async function compileGatsbyFiles(
   retry: number = 0
 ): Promise<void> {
   try {
+    const configName = `gatsby-node`
+
     // Check for gatsby-node.jsx and gatsby-node.tsx (or other misnamed variations)
-    const files = await readdir(siteRoot)
+    const filesAndDirectories = await readdir(siteRoot, { withFileTypes: true })
+    const files = filesAndDirectories
+      .filter(dirent => !dirent.isDirectory())
+      .map(dirent => dirent.name)
+
+    // Check if they have a gatsby-node directory for lifecycle function code.
+    const hasGatsbyNodeDir =
+      filesAndDirectories.filter(
+        dirent => dirent.isDirectory() && dirent.name === configName
+      ).length > 0
 
     let nearMatch = ``
-    const configName = `gatsby-node`
 
     for (const file of files) {
       if (nearMatch) {
         break
       }
 
       const { name } = path.parse(file)
+
       // Of course, allow valid gatsby-node files
       if (file === `gatsby-node.js` || file === `gatsby-node.ts`) {
         break
       }
 
-      if (isNearMatch(name, configName, 3)) {
+      // Check for likely misnamed files, but allow a 'gatsby-node' directory.
+      if (isNearMatch(name, configName, 3) && !hasGatsbyNodeDir) {
         nearMatch = file
       }
     }