fix: make mapESLintTemplate optional with default value

Author: chenjiahan

src/index.ts

@@ -234,7 +234,11 @@ export async function create({
   skipFiles?: string[];
   templates: string[];
   getTemplateName: (argv: Argv) => Promise<string>;
-  mapESLintTemplate: (
+  /**
+   * Map the template name to the ESLint template name.
+   * @default () => 'vanilla-ts'
+   */
+  mapESLintTemplate?: (
     templateName: string,
     context: { distFolder: string },
   ) => ESLintTemplateName | null;
@@ -351,9 +355,11 @@ export async function create({
     const toolFolder = path.join(packageRoot, `template-${tool}`);
 
     if (tool === 'eslint') {
-      const eslintTemplateName = mapESLintTemplate(templateName, {
-        distFolder,
-      });
+      const eslintTemplateName = mapESLintTemplate
+        ? mapESLintTemplate(templateName, {
+            distFolder,
+          })
+        : 'vanilla-ts';
 
       if (!eslintTemplateName) {
         continue;

test/agents.test.ts

@@ -37,7 +37,6 @@ test('should generate AGENTS.md with no tools selected', async () => {
     root: fixturesDir,
     templates: ['vanilla'],
     getTemplateName: async () => 'vanilla',
-    mapESLintTemplate: () => null,
   });
 
   const agentsPath = path.join(projectDir, 'AGENTS.md');
@@ -92,7 +91,6 @@ test('should generate AGENTS.md with single tool selected', async () => {
     root: fixturesDir,
     templates: ['vanilla'],
     getTemplateName: async () => 'vanilla',
-    mapESLintTemplate: () => null,
   });
 
   const agentsPath = path.join(projectDir, 'AGENTS.md');
@@ -205,7 +203,6 @@ test('should merge top-level sections from AGENTS.md files', async () => {
     root: fixturesDir,
     templates: ['vanilla'],
     getTemplateName: async () => 'vanilla',
-    mapESLintTemplate: () => null,
   });
 
   const agentsPath = path.join(projectDir, 'AGENTS.md');

test/custom-tools.test.ts

@@ -45,7 +45,6 @@ test('should run extra tool action', async () => {
     root: fixturesDir,
     templates: ['vanilla'],
     getTemplateName: async () => 'vanilla',
-    mapESLintTemplate: () => null,
     extraTools: [
       {
         value: 'custom-action',
@@ -82,7 +81,6 @@ test('should run extra tool command', async () => {
     root: fixturesDir,
     templates: ['vanilla'],
     getTemplateName: async () => 'vanilla',
-    mapESLintTemplate: () => null,
     extraTools: [
       {
         value: 'custom-command',