fix(eslint-plugin): [prefer-includes] don't auto fix when test meth…

…od's argument type doesn't have an 'includes' method (#2391)
typescript-eslint · Aug 13, 2020 · 71c4c72 · 71c4c72
1 parent 8318c36
commit 71c4c72
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diff --git a/packages/eslint-plugin/src/rules/prefer-includes.ts b/packages/eslint-plugin/src/rules/prefer-includes.ts
@@ -4,7 +4,12 @@ import {
 } from '@typescript-eslint/experimental-utils';
 import { AST as RegExpAST, parseRegExpLiteral } from 'regexpp';
 import * as ts from 'typescript';
-import { createRule, getParserServices, getStaticValue } from '../util';
+import {
+  createRule,
+  getParserServices,
+  getStaticValue,
+  getConstrainedTypeAtLocation,
+} from '../util';
 
 export default createRule({
   name: 'prefer-includes',
@@ -191,6 +196,18 @@ export default createRule({
           return;
         }
 
+        //check the argument type of test methods
+        const argument = callNode.arguments[0];
+        const tsNode = services.esTreeNodeToTSNodeMap.get(argument);
+        const type = getConstrainedTypeAtLocation(types, tsNode);
+
+        const includesMethodDecl = type
+          .getProperty('includes')
+          ?.getDeclarations();
+        if (includesMethodDecl == null) {
+          return;
+        }
+
         context.report({
           node: callNode,
           messageId: 'preferStringIncludes',

diff --git a/packages/eslint-plugin/tests/rules/prefer-includes.test.ts b/packages/eslint-plugin/tests/rules/prefer-includes.test.ts
@@ -115,6 +115,12 @@ ruleTester.run('prefer-includes', rule, {
         something.test(a)
       }
     `,
+    `
+      const pattern = new RegExp("bar")
+      function f(a) {
+        return pattern.test(a)
+      }
+    `,
   ]),
   invalid: addOptional([
     // positive