feat: exit with error when cmkOptions.enabled is false

When css-modules-kit is disabled by configuration (`enabled: false`),
the codegen now throws CMKDisabledError and exits with code 1 instead
of silently proceeding. This applies to both normal and watch modes.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: mizdra

packages/codegen/src/error.ts

@@ -17,3 +17,12 @@ export class ReadCSSModuleFileError extends SystemError {
     super('READ_CSS_MODULE_FILE_ERROR', `Failed to read CSS Module file ${fileName}.`, cause);
   }
 }
+
+export class CMKDisabledError extends SystemError {
+  constructor(configFileName: string) {
+    super(
+      'CMK_DISABLED_ERROR',
+      `css-modules-kit is disabled by configuration. Set \`"cmkOptions": { "enabled": true }\` in ${configFileName} to enable it.`,
+    );
+  }
+}

packages/codegen/src/index.ts

@@ -1,5 +1,5 @@
 export { runCMK, runCMKInWatchMode } from './runner.js';
 export { type Logger, createLogger } from './logger/logger.js';
-export { WriteDtsFileError, ReadCSSModuleFileError } from './error.js';
+export { WriteDtsFileError, ReadCSSModuleFileError, CMKDisabledError } from './error.js';
 export { parseCLIArgs, printHelpText, printVersion } from './cli.js';
 export { shouldBePretty } from './3rd-party/typescript.js';

packages/codegen/src/runner.test.ts

@@ -2,6 +2,7 @@ import { access, rm, writeFile } from 'node:fs/promises';
 import { platform } from 'node:process';
 import dedent from 'dedent';
 import { afterEach, describe, expect, test, vi } from 'vitest';
+import { CMKDisabledError } from './error.js';
 import type { Watcher } from './runner.js';
 import { runCMK, runCMKInWatchMode } from './runner.js';
 import { formatDiagnostics } from './test/diagnostic.js';
@@ -100,6 +101,13 @@ describe('runCMK', () => {
     await expect(access(iff.join('generated/src/a.module.css.d.ts'))).resolves.not.toThrow();
     await expect(access(iff.join('generated/src/old.module.css.d.ts'))).rejects.toThrow();
   });
+  test('throws CMKDisabledError if enabled is false', async () => {
+    const iff = await createIFF({
+      'tsconfig.json': '{ "cmkOptions": { "enabled": false } }',
+      'src/a.module.css': '.a_1 { color: red; }',
+    });
+    await expect(runCMK(fakeParsedArgs({ project: iff.rootDir }), createLoggerSpy())).rejects.toThrow(CMKDisabledError);
+  });
 });
 
 describe('runCMKInWatchMode', () => {
@@ -305,4 +313,13 @@ describe('runCMKInWatchMode', () => {
     watcher = await runCMKInWatchMode(fakeParsedArgs({ project: iff.rootDir, preserveWatchOutput: true }), loggerSpy2);
     expect(loggerSpy2.clearScreen).toHaveBeenCalledTimes(0);
   });
+  test('throws CMKDisabledError if enabled is false', async () => {
+    const iff = await createIFF({
+      'tsconfig.json': '{ "cmkOptions": { "enabled": false } }',
+      'src/a.module.css': '.a_1 { color: red; }',
+    });
+    await expect(runCMKInWatchMode(fakeParsedArgs({ project: iff.rootDir }), createLoggerSpy())).rejects.toThrow(
+      CMKDisabledError,
+    );
+  });
 });

packages/codegen/src/runner.ts

@@ -1,6 +1,7 @@
 import type { Stats } from 'node:fs';
 import { rm } from 'node:fs/promises';
 import chokidar, { type FSWatcher } from 'chokidar';
+import { CMKDisabledError } from './error.js';
 import type { Logger } from './logger/logger.js';
 import { createProject, type Project } from './project.js';
 
@@ -19,12 +20,16 @@ export interface Watcher {
 /**
  * Run css-modules-kit .d.ts generation.
  * @param project The absolute path to the project directory or the path to `tsconfig.json`.
+ * @throws {CMKDisabledError} When css-modules-kit is disabled.
  * @throws {ReadCSSModuleFileError} When failed to read CSS Module file.
  * @throws {WriteDtsFileError}
  * @returns Whether the process succeeded without errors.
  */
 export async function runCMK(args: RunnerArgs, logger: Logger): Promise<boolean> {
   const project = createProject(args);
+  if (project.config.enabled === false) {
+    throw new CMKDisabledError(project.config.configFileName);
+  }
   if (args.clean) {
     await rm(project.config.dtsOutDir, { recursive: true, force: true });
   }
@@ -46,13 +51,17 @@ export async function runCMK(args: RunnerArgs, logger: Logger): Promise<boolean>
  *
  * NOTE: For implementation simplicity, config file changes are not watched.
  * @param project The absolute path to the project directory or the path to `tsconfig.json`.
+ * @throws {CMKDisabledError} When css-modules-kit is disabled.
  * @throws {TsConfigFileNotFoundError}
  * @throws {ReadCSSModuleFileError}
  * @throws {WriteDtsFileError}
  */
 export async function runCMKInWatchMode(args: RunnerArgs, logger: Logger): Promise<Watcher> {
   const fsWatchers: FSWatcher[] = [];
   const project = createProject(args);
+  if (project.config.enabled === false) {
+    throw new CMKDisabledError(project.config.configFileName);
+  }
   let emitAndReportDiagnosticsTimer: NodeJS.Timeout | undefined = undefined;
 
   if (args.clean) {