fix(core): avoid changing existing project name if a project.json file is added to a project

packages/nx/src/generators/utils/project-configuration.ts

@@ -279,14 +279,29 @@ function readAndCombineAllProjectConfigurations(tree: Tree): {
     if (basename(projectFile) === 'project.json') {
       const json = readJson(tree, projectFile);
       const config = buildProjectFromProjectJson(json, projectFile);
+      if (!config.name) {
+        try {
+          const packageJson = readJson<PackageJson>(
+            tree,
+            joinPathFragments(config.root, 'package.json')
+          );
+          if (packageJson.name) {
+            config.name = packageJson.name;
+          }
+        } catch {
+          // Maybe no package json, is ok.
+        }
+        config.name ??= toProjectName(projectFile);
+      }
       mergeProjectConfigurationIntoRootMap(
         rootMap,
         config,
         undefined,
         undefined,
         true
       );
-    } else if (basename(projectFile) === 'package.json') {
+    }
+    if (basename(projectFile) === 'package.json') {
       const packageJson = readJson<PackageJson>(tree, projectFile);
 
       // We don't want to have all of the extra inferred stuff in here, as

packages/nx/src/plugins/package-json/create-nodes.ts

@@ -202,7 +202,7 @@ export function buildProjectConfigurationFromPackageJson(
     }
   }
 
-  if (!packageJson.name && projectRoot === '.') {
+  if (!packageJson.name && projectRoot === '.' && !packageJson.nx?.name) {
     throw new Error(
       'Nx requires the root package.json to specify a name if it is being used as an Nx project.'
     );

packages/nx/src/plugins/project-json/build-nodes/project-json.ts

@@ -1,13 +1,11 @@
 import { dirname, join } from 'node:path';
 
 import { ProjectConfiguration } from '../../../config/workspace-json-project-json';
-import { toProjectName } from '../../../config/to-project-name';
 import { readJsonFile } from '../../../utils/fileutils';
 import {
   createNodesFromFiles,
   NxPluginV2,
 } from '../../../project-graph/plugins';
-import { PackageJson } from '../../../utils/package-json';
 
 export const ProjectJsonProjectsPlugin: NxPluginV2 = {
   name: 'nx/core/project-json',
@@ -42,21 +40,10 @@ export function buildProjectFromProjectJson(
   json: Partial<ProjectConfiguration>,
   path: string
 ): ProjectConfiguration {
-  const packageJsonPath = join(dirname(path), 'package.json');
   const { name, root, ...rest } = json;
   return {
-    name:
-      name ?? readNameFromPackageJson(packageJsonPath) ?? toProjectName(path),
+    name,
     root: root ?? dirname(path),
     ...rest,
   };
 }
-
-export function readNameFromPackageJson(path: string): string {
-  try {
-    const json = readJsonFile<PackageJson>(path);
-    return json.nx?.name ?? json.name;
-  } catch {
-    return undefined;
-  }
-}

packages/nx/src/project-graph/utils/project-configuration-utils.ts

@@ -13,6 +13,7 @@ import { workspaceRoot } from '../../utils/workspace-root';
 import { minimatch } from 'minimatch';
 import { join } from 'path';
 import { performance } from 'perf_hooks';
+import { existsSync } from 'node:fs';
 
 import { LoadedNxPlugin } from '../plugins/loaded-nx-plugin';
 import {
@@ -37,6 +38,7 @@ import {
   getExecutorInformation,
   parseExecutor,
 } from '../../command-line/run/executor-utils';
+import { toProjectName } from '../../config/to-project-name';
 
 export type SourceInformation = [file: string | null, plugin: string];
 export type ConfigurationSourceMaps = Record<
@@ -668,6 +670,16 @@ function validateAndNormalizeProjectRootMap(
     // Strip it before returning configuration for usage.
     if (project['// targets']) delete project['// targets'];
 
+    // We initially did this in the project.json plugin, but
+    // that resulted in project.json files without names causing
+    // the resulting project to change names from earlier plugins...
+    if (
+      !project.name &&
+      existsSync(join(workspaceRoot, project.root, 'project.json'))
+    ) {
+      project.name = toProjectName(join(root, 'project.json'));
+    }
+
     try {
       validateProject(project, projects);
       projects[project.name] = project;