template-missing-invokable: add built-in invokables and always auto-fix from config

.gitignore

@@ -14,3 +14,6 @@ npm-debug.log
 
 # eslint-remote-tester
 eslint-remote-tester-results
+
+# npm lock file (project uses pnpm)
+package-lock.json

lib/rules/template-missing-invokable.js

@@ -1,3 +1,58 @@
+'use strict';
+
+const path = require('node:path');
+const fs = require('node:fs');
+
+// Packages that ship with Ember/Glimmer are always available to auto-fix.
+function isBuiltinPackage(moduleName) {
+  return moduleName.startsWith('@ember/') || moduleName.startsWith('@glimmer/');
+}
+
+// Returns the root package name from a module specifier, e.g.
+//   'ember-truth-helpers'          -> 'ember-truth-helpers'
+//   'ember-truth-helpers/helpers'  -> 'ember-truth-helpers'
+//   '@scope/pkg/deep'              -> '@scope/pkg'
+function rootPackageName(moduleName) {
+  if (moduleName.startsWith('@')) {
+    const parts = moduleName.split('/');
+    return parts.slice(0, 2).join('/');
+  }
+  return moduleName.split('/')[0];
+}
+
+// Walk up the directory tree from startDir to find the nearest package.json.
+function findNearestPackageJson(startDir) {
+  let dir = startDir;
+  let parent = path.dirname(dir);
+  while (dir !== parent) {
+    const candidate = path.join(dir, 'package.json');
+    if (fs.existsSync(candidate)) {
+      return candidate;
+    }
+    dir = parent;
+    parent = path.dirname(dir);
+  }
+  return null;
+}
+
+function isPackageInProjectDeps(moduleName, fileDir) {
+  try {
+    const pkgPath = findNearestPackageJson(fileDir);
+    if (!pkgPath) {
+      return false;
+    }
+    const packageJson = JSON.parse(fs.readFileSync(pkgPath, 'utf8'));
+    const pkg = rootPackageName(moduleName);
+    return Boolean(
+      (packageJson.dependencies && pkg in packageJson.dependencies) ||
+        (packageJson.devDependencies && pkg in packageJson.devDependencies) ||
+        (packageJson.peerDependencies && pkg in packageJson.peerDependencies)
+    );
+  } catch {
+    return false;
+  }
+}
+
 /** @type {import('eslint').Rule.RuleModule} */
 module.exports = {
   meta: {
@@ -41,14 +96,23 @@ module.exports = {
         if (!isBound(node.path.head, sourceCode.getScope(node.path))) {
           const matched = context.options[0]?.invokables?.[node.path.head.name];
           if (matched) {
-            const [name, module] = matched;
-            const importStatement = buildImportStatement(node.path.head.name, name, module);
+            const [name, moduleName] = matched;
+            const fileDir = path.dirname(
+              path.resolve(context.getPhysicalFilename?.() ?? context.getFilename())
+            );
+            const canAutoFix =
+              isBuiltinPackage(moduleName) ||
+              isPackageInProjectDeps(moduleName, fileDir);
+
+            const importStatement = buildImportStatement(node.path.head.name, name, moduleName);
             context.report({
               node: node.path,
               messageId: 'missing-invokable',
-              fix(fixer) {
-                return fixer.insertTextBeforeRange([0, 0], `${importStatement};\n`);
-              },
+              fix: canAutoFix
+                ? function (fixer) {
+                    return fixer.insertTextBeforeRange([0, 0], `${importStatement};\n`);
+                  }
+                : null,
             });
           }
         }

tests/fixtures/projects/has-ember-truth-helpers/package.json

@@ -0,0 +1,6 @@
+{
+  "name": "has-ember-truth-helpers",
+  "dependencies": {
+    "ember-truth-helpers": "*"
+  }
+}

tests/lib/rules/template-missing-invokable.js

@@ -2,9 +2,20 @@
 // Requirements
 //------------------------------------------------------------------------------
 
+const path = require('node:path');
 const rule = require('../../../lib/rules/template-missing-invokable');
 const RuleTester = require('eslint').RuleTester;
 
+//------------------------------------------------------------------------------
+// Helpers
+//------------------------------------------------------------------------------
+
+// A filename inside a fixture project that has ember-truth-helpers installed.
+const filenameInProjectWithTruthHelpers = path.join(
+  __dirname,
+  '../../fixtures/projects/has-ember-truth-helpers/test.gjs'
+);
+
 //------------------------------------------------------------------------------
 // Tests
 //------------------------------------------------------------------------------
@@ -68,8 +79,30 @@ ruleTester.run('template-missing-invokable', rule, {
   ],
 
   invalid: [
-    // Subexpression invocations
+    // Subexpression invocations — no auto-fix when package is not in project deps
+    {
+      code: `
+      <template>
+        {{#if (eq 1 1)}}
+          They're equal
+        {{/if}}
+      </template>
+      `,
+      output: null,
+      options: [
+        {
+          invokables: {
+            eq: ['eq', 'ember-truth-helpers'],
+          },
+        },
+      ],
+
+      errors: [{ type: 'GlimmerPathExpression', message: rule.meta.messages['missing-invokable'] }],
+    },
+
+    // Subexpression invocations — auto-fix when package IS in project deps
     {
+      filename: filenameInProjectWithTruthHelpers,
       code: `
       <template>
         {{#if (eq 1 1)}}
@@ -96,19 +129,14 @@ ruleTester.run('template-missing-invokable', rule, {
       errors: [{ type: 'GlimmerPathExpression', message: rule.meta.messages['missing-invokable'] }],
     },
 
-    // Mustache Invocations
+    // Mustache Invocations — no auto-fix when package is not in project deps
     {
       code: `
       <template>
         {{eq 1 1}}
       </template>
     `,
-      output: `import { eq } from 'ember-truth-helpers';
-
-      <template>
-        {{eq 1 1}}
-      </template>
-    `,
+      output: null,
       options: [
         {
           invokables: {
@@ -119,6 +147,7 @@ ruleTester.run('template-missing-invokable', rule, {
       errors: [{ type: 'GlimmerPathExpression', message: rule.meta.messages['missing-invokable'] }],
     },
     {
+      filename: filenameInProjectWithTruthHelpers,
       code: `
       import MyComponent from 'somewhere';
       <template>
@@ -142,7 +171,7 @@ ruleTester.run('template-missing-invokable', rule, {
       errors: [{ type: 'GlimmerPathExpression', message: rule.meta.messages['missing-invokable'] }],
     },
 
-    // Modifier Inovcations
+    // Modifier Invocations — built-in package always auto-fixes
     {
       code: `
         function doSomething() {}
@@ -167,8 +196,9 @@ ruleTester.run('template-missing-invokable', rule, {
       errors: [{ type: 'GlimmerPathExpression', message: rule.meta.messages['missing-invokable'] }],
     },
 
-    // Multiple copies of a fixable invocation
+    // Multiple copies of a fixable invocation — with package installed
     {
+      filename: filenameInProjectWithTruthHelpers,
       code: `
         let other = <template>
           {{#if (eq 3 3) }}
@@ -216,8 +246,9 @@ ruleTester.run('template-missing-invokable', rule, {
       ],
     },
 
-    // Auto-fix with a default export
+    // Auto-fix with a default export — package installed
     {
+      filename: filenameInProjectWithTruthHelpers,
       code: `
       <template>
         {{#if (eq 1 1)}}