fix: Escape RegExp characters in suffix.

Author: cartant

source/rules/suffix-subjects.ts

@@ -11,7 +11,7 @@ import {
   getParserServices,
   getTypeServices,
 } from "eslint-etc";
-import { ruleCreator } from "../utils";
+import { escapeRegExp, ruleCreator } from "../utils";
 
 const defaultOptions: readonly {
   parameters?: boolean;
@@ -75,7 +75,10 @@ const rule = ruleCreator({
     }
 
     const { suffix = "Subject" } = config;
-    const suffixRegex = new RegExp(String.raw`${suffix}\$?$`, "i");
+    const suffixRegex = new RegExp(
+      String.raw`${escapeRegExp(suffix)}\$?$`,
+      "i"
+    );
 
     function checkNode(nameNode: es.Node, typeNode?: es.Node) {
       let tsNode = esTreeNodeToTSNodeMap.get(nameNode);

source/utils.ts

@@ -20,6 +20,11 @@ export function createRegExpForWords(
   return new RegExp(`(${joined})`, flags);
 }
 
+export function escapeRegExp(text: string): string {
+  // https://stackoverflow.com/a/3561711/6680611
+  return text.replace(/[-\/\\^$*+?.()|[\]{}]/g, "\\$&");
+}
+
 export const ruleCreator = ESLintUtils.RuleCreator(
   (name) =>
     `https://github.com/cartant/eslint-plugin-rxjs/tree/main/docs/rules/${name}.md`

tests/rules/suffix-subjects.ts

@@ -591,6 +591,19 @@ ruleTester({ types: true }).run("suffix-subjects", rule, {
               ~~~~~~ [forbidden { "suffix": "Subject" }]
       `
     ),
+    fromFixture(
+      stripIndent`
+        // BehaviorSubject with $$ suffix
+        // https://github.com/cartant/eslint-plugin-rxjs/issues/88
+        import { BehaviorSubject } from "rxjs";
+
+        const subject$ = new BehaviorSubject<number>(42);
+              ~~~~~~~~ [forbidden { "suffix": "$$" }]
+        const someSubject$ = new BehaviorSubject<number>(54);
+              ~~~~~~~~~~~~ [forbidden { "suffix": "$$" }]
+      `,
+      { options: [{ suffix: "$$" }] }
+    ),
     fromFixture(
       stripIndent`
         // MySubject without suffix