Improve and clarify error for missing scheme file (#2599)

* Add test for getBuildConfigurationFromXcScheme

* Remove extra apostrophe from schemes error message

* Improve and clarify error for missing scheme file

Author: friederbluemle

packages/cli-platform-apple/src/tools/__tests__/getBuildConfigurationFromXcScheme.test.ts

@@ -0,0 +1,100 @@
+import {getBuildConfigurationFromXcScheme} from '../getBuildConfigurationFromXcScheme';
+import fs from 'fs';
+import path from 'path';
+import {CLIError} from '@react-native-community/cli-tools';
+
+jest.mock('fs', () => ({
+  readFileSync: jest.fn(),
+  readdirSync: jest.fn(),
+}));
+
+describe('getBuildConfigurationFromXcScheme', () => {
+  afterEach(() => {
+    jest.resetAllMocks();
+  });
+
+  it('returns build configuration when the shared scheme file exists', () => {
+    (fs.readdirSync as jest.Mock).mockReturnValue(['Test.xcodeproj']);
+
+    const xmlContent = `<Scheme>
+  <LaunchAction buildConfiguration="Debug"/>
+</Scheme>`;
+    (fs.readFileSync as jest.Mock).mockReturnValue(xmlContent);
+
+    const sourceDir = '/some/dir';
+    const scheme = 'Test';
+    const defaultConfig = 'Release';
+    const projectInfo = {name: 'Test', schemes: [scheme]};
+
+    const result = getBuildConfigurationFromXcScheme(
+      scheme,
+      defaultConfig,
+      sourceDir,
+      projectInfo,
+    );
+
+    expect(result).toBe('Debug');
+
+    const expectedPath = path.join(
+      sourceDir,
+      'Test.xcodeproj',
+      'xcshareddata',
+      'xcschemes',
+      `${scheme}.xcscheme`,
+    );
+    expect(fs.readFileSync).toHaveBeenCalledWith(expectedPath, {
+      encoding: 'utf-8',
+    });
+  });
+
+  it('throws CLIError when reading the shared scheme file fails', () => {
+    process.env.FORCE_COLOR = '0'; // To disable chalk
+    (fs.readdirSync as jest.Mock).mockReturnValue(['Test.xcodeproj']);
+    (fs.readFileSync as jest.Mock).mockImplementation(() => {
+      throw new Error('File not found');
+    });
+
+    const sourceDir = '/some/dir';
+    const scheme = 'Test';
+    const defaultConfig = 'Release';
+    const projectInfo = {name: 'Test', schemes: [scheme]};
+
+    expect(() => {
+      getBuildConfigurationFromXcScheme(
+        scheme,
+        defaultConfig,
+        sourceDir,
+        projectInfo,
+      );
+    }).toThrow(CLIError);
+
+    try {
+      getBuildConfigurationFromXcScheme(
+        scheme,
+        defaultConfig,
+        sourceDir,
+        projectInfo,
+      );
+    } catch (err) {
+      const msg = (err as CLIError).message;
+      expect(msg).toContain(`Could not load the shared scheme for ${scheme}`);
+      expect(msg).toContain(`includes: ${projectInfo.schemes[0]}`);
+    }
+  });
+
+  it('returns the default configuration when no .xcodeproj folder is found', () => {
+    (fs.readdirSync as jest.Mock).mockReturnValue([]);
+
+    const sourceDir = '/some/dir';
+    const scheme = 'Test';
+    const defaultConfig = 'Release';
+    const result = getBuildConfigurationFromXcScheme(
+      scheme,
+      defaultConfig,
+      sourceDir,
+      undefined,
+    );
+
+    expect(result).toBe(defaultConfig);
+  });
+});

packages/cli-platform-apple/src/tools/getBuildConfigurationFromXcScheme.ts

@@ -39,15 +39,13 @@ export function getBuildConfigurationFromXcScheme(
       return Scheme.LaunchAction['@_buildConfiguration'];
     }
   } catch {
-    const availableSchemas =
-      projectInfo && projectInfo.schemes && projectInfo.schemes.length > 0
-        ? `Available schemas are: ${projectInfo.schemes
-            .map((name) => chalk.bold(name))
-            .join(', ')}'`
-        : '';
+    const projectSchemes =
+      projectInfo?.schemes && projectInfo.schemes.length > 0
+        ? `${projectInfo.schemes.map((name) => chalk.bold(name)).join(', ')}`
+        : 'No schemes';
 
     throw new CLIError(
-      `Could not find scheme ${scheme}. Please make sure the schema you want to run exists. ${availableSchemas}`,
+      `Could not load the shared scheme for ${scheme}. Your project configuration includes: ${projectSchemes}. Please ensure a valid .xcscheme file exists in xcshareddata/xcschemes.`,
     );
   }