fix(eslint-plugin): [member-naming] should match constructor args (#771)

packages/eslint-plugin/src/rules/member-naming.ts

@@ -1,4 +1,7 @@
-import { TSESTree } from '@typescript-eslint/experimental-utils';
+import {
+  TSESTree,
+  AST_NODE_TYPES,
+} from '@typescript-eslint/experimental-utils';
 import * as util from '../util';
 
 interface Config<T = string> {
@@ -61,37 +64,73 @@ export default util.createRule<Options, MessageIds>({
       return acc;
     }, {});
 
-    /**
-     * Check that the property name matches the convention for its
-     * accessibility.
-     * @param {ASTNode} node the named node to evaluate.
-     * @returns {void}
-     * @private
-     */
+    function getParameterNode(
+      node: TSESTree.TSParameterProperty,
+    ): TSESTree.Identifier | null {
+      if (node.parameter.type === AST_NODE_TYPES.AssignmentPattern) {
+        return node.parameter.left as TSESTree.Identifier;
+      }
+
+      if (node.parameter.type === AST_NODE_TYPES.Identifier) {
+        return node.parameter;
+      }
+
+      return null;
+    }
+
+    function validateParameterName(node: TSESTree.TSParameterProperty): void {
+      const parameterNode = getParameterNode(node);
+      if (!parameterNode) {
+        return;
+      }
+
+      validate(parameterNode, parameterNode.name, node.accessibility);
+    }
+
     function validateName(
       node: TSESTree.MethodDefinition | TSESTree.ClassProperty,
     ): void {
-      const name = util.getNameFromClassMember(node, sourceCode);
-      const accessibility: Modifiers = node.accessibility || 'public';
-      const convention = conventions[accessibility];
-
-      const method = node as TSESTree.MethodDefinition;
-      if (method.kind === 'constructor') {
+      if (
+        node.type === AST_NODE_TYPES.MethodDefinition &&
+        node.kind === 'constructor'
+      ) {
         return;
       }
 
+      validate(
+        node.key,
+        util.getNameFromClassMember(node, sourceCode),
+        node.accessibility,
+      );
+    }
+
+    /**
+     * Check that the name matches the convention for its accessibility.
+     * @param {ASTNode}   node the named node to evaluate.
+     * @param {string}    name
+     * @param {Modifiers} accessibility
+     * @returns {void}
+     * @private
+     */
+    function validate(
+      node: TSESTree.Identifier | TSESTree.Expression,
+      name: string,
+      accessibility: Modifiers = 'public',
+    ): void {
+      const convention = conventions[accessibility];
       if (!convention || convention.test(name)) {
         return;
       }
 
       context.report({
-        node: node.key,
+        node,
         messageId: 'incorrectName',
         data: { accessibility, name, convention },
       });
     }
 
     return {
+      TSParameterProperty: validateParameterName,
       MethodDefinition: validateName,
       ClassProperty: validateName,
     };

packages/eslint-plugin/tests/rules/member-naming.test.ts

@@ -86,6 +86,30 @@ class Class {
         },
       ],
     },
+
+    {
+      code: `
+class Test {
+    constructor(public __a: string, protected __b: string, private __c: string = 100) {}
+}
+      `,
+      options: [
+        {
+          protected: '^__',
+          private: '^__',
+          public: '^__',
+        },
+      ],
+    },
+    {
+      code:
+        // Semantically invalid test case, TS has to throw an error.
+        `
+class Foo {
+    constructor(private ...name: string[], private [test]: [string]) {}
+}
+      `,
+    },
   ],
   invalid: [
     {
@@ -329,5 +353,51 @@ class Class {
         },
       ],
     },
+    {
+      code: `
+class Test {
+    constructor(public a: string, protected b: string, private c: string = 100) {}
+}
+      `,
+      options: [
+        {
+          public: '^__',
+          protected: '^__',
+          private: '^__',
+        },
+      ],
+      errors: [
+        {
+          messageId: 'incorrectName',
+          data: {
+            accessibility: 'public',
+            convention: '/^__/',
+            name: 'a',
+          },
+          line: 3,
+          column: 24,
+        },
+        {
+          messageId: 'incorrectName',
+          data: {
+            accessibility: 'protected',
+            convention: '/^__/',
+            name: 'b',
+          },
+          line: 3,
+          column: 45,
+        },
+        {
+          messageId: 'incorrectName',
+          data: {
+            accessibility: 'private',
+            convention: '/^__/',
+            name: 'c',
+          },
+          line: 3,
+          column: 64,
+        },
+      ],
+    },
   ],
 });