Fix template-require-form-method: throw on bad config; default disabled

parseConfig now throws on invalid allowedMethods (matches upstream's
strictness instead of silently disabling). parseConfig(undefined)
returns false so the rule doesn't run when options are omitted
(matches upstream default). Schema accepts boolean root for parity.

Author: johanrd

lib/rules/template-require-form-method.js

@@ -26,7 +26,16 @@ function parseConfig(config) {
     }
   }
 
-  return false;
+  // Invalid configuration (e.g. unknown method in allowedMethods). Throw a
+  // descriptive error to surface the problem to the user, matching upstream
+  // ember-template-lint (which throws instead of silently disabling).
+  throw new Error(
+    'template-require-form-method: invalid configuration. Expected one of:\n' +
+      '  * boolean - `true` to enable / `false` to disable\n' +
+      '  * object -- An object with the following keys:\n' +
+      `    * \`allowedMethods\` -- An array of allowed form \`method\` attribute values of \`${VALID_FORM_METHODS}\`\n` +
+      `Received: ${JSON.stringify(config)}`
+  );
 }
 
 function makeErrorMessage(methods) {
@@ -51,12 +60,16 @@ module.exports = {
     schema: [
       {
         oneOf: [
+          { type: 'boolean' },
           {
             type: 'object',
             properties: {
               allowedMethods: {
                 type: 'array',
                 items: {
+                  // Accept any string so case-insensitive values like "get"
+                  // still pass schema validation; parseConfig normalizes to
+                  // upper-case and throws on values not in VALID_FORM_METHODS.
                   type: 'string',
                 },
               },
@@ -78,9 +91,12 @@ module.exports = {
   },
 
   create(context) {
-    // If no options provided, use defaults
-    let config = context.options[0];
-    config = config ? parseConfig(config) : DEFAULT_CONFIG;
+    // Match upstream ember-template-lint: when no options are provided,
+    // parseConfig(undefined) returns false and the rule is disabled. This
+    // rule must be enabled explicitly via `true` or an `allowedMethods`
+    // object.
+    const rawOption = context.options[0];
+    const config = parseConfig(rawOption);
 
     if (config === false) {
       return {};

tests/lib/rules/template-require-form-method.js

@@ -9,17 +9,22 @@ const validHbs = [
     options: [{ allowedMethods: ['get'] }],
     code: '<form method="GET"></form>',
   },
-  '<form method="POST"></form>',
-  '<form method="post"></form>',
-  '<form method="GET"></form>',
-  '<form method="get"></form>',
-  '<form method="DIALOG"></form>',
-  '<form method="dialog"></form>',
-  '<form method="{{formMethod}}"></form>',
-  '<form method={{formMethod}}></form>',
-  '<div/>',
-  '<div></div>',
-  '<div method="randomType"></div>',
+  // Default behavior: when no options are provided, the rule is disabled
+  // (matching upstream ember-template-lint). A bare <form> should NOT error.
+  '<form></form>',
+  '<form method="NOT_A_VALID_METHOD"></form>',
+  { options: [true], code: '<form method="POST"></form>' },
+  { options: [true], code: '<form method="post"></form>' },
+  { options: [true], code: '<form method="GET"></form>' },
+  { options: [true], code: '<form method="get"></form>' },
+  { options: [true], code: '<form method="DIALOG"></form>' },
+  { options: [true], code: '<form method="dialog"></form>' },
+  { options: [true], code: '<form method="{{formMethod}}"></form>' },
+  { options: [true], code: '<form method={{formMethod}}></form>' },
+  { options: [true], code: '<div/>' },
+  { options: [true], code: '<div></div>' },
+  { options: [true], code: '<div method="randomType"></div>' },
+  { options: [false], code: '<form></form>' },
 ];
 
 const invalidHbs = [
@@ -40,26 +45,31 @@ const invalidHbs = [
     ],
   },
   {
+    options: [true],
     code: '<form></form>',
     output: '<form method="POST"></form>',
     errors: [{ message: DEFAULT_ERROR }],
   },
   {
+    options: [true],
     code: '<form method=""></form>',
     output: '<form method="POST"></form>',
     errors: [{ message: DEFAULT_ERROR }],
   },
   {
+    options: [true],
     code: '<form method=42></form>',
     output: '<form method="POST"></form>',
     errors: [{ message: DEFAULT_ERROR }],
   },
   {
+    options: [true],
     code: '<form method=" ge t "></form>',
     output: '<form method="POST"></form>',
     errors: [{ message: DEFAULT_ERROR }],
   },
   {
+    options: [true],
     code: '<form method=" pos t "></form>',
     output: '<form method="POST"></form>',
     errors: [{ message: DEFAULT_ERROR }],
@@ -100,3 +110,28 @@ hbsRuleTester.run('template-require-form-method', rule, {
   valid: validHbs,
   invalid: invalidHbs,
 });
+
+// Upstream-aligned error-surfacing tests. parseConfig should throw on an
+// invalid `allowedMethods` entry rather than silently disabling the rule.
+describe('template-require-form-method invalid configuration', () => {
+  const { Linter } = require('eslint');
+
+  function lintWith(options) {
+    const linter = new Linter();
+    linter.defineParser('ember-eslint-parser/hbs', require('ember-eslint-parser/hbs'));
+    linter.defineRule('template-require-form-method', rule);
+    return linter.verify('<form method="POST"></form>', {
+      parser: 'ember-eslint-parser/hbs',
+      parserOptions: { ecmaVersion: 2022, sourceType: 'module' },
+      rules: { 'template-require-form-method': ['error', options] },
+    });
+  }
+
+  test('throws on unknown method in allowedMethods', () => {
+    expect(() => lintWith({ allowedMethods: ['PATCH'] })).toThrow(/invalid configuration/);
+  });
+
+  test('throws on mixed valid/invalid method list', () => {
+    expect(() => lintWith({ allowedMethods: ['GET', 'BOGUS'] })).toThrow(/invalid configuration/);
+  });
+});