1 files changed, 38 insertions, 0 deletions
diff --git a/tools/lint/eslint/eslint-plugin-mozilla/tests/use-includes-instead-of-indexOf.js b/tools/lint/eslint/eslint-plugin-mozilla/tests/use-includes-instead-of-indexOf.js
new file mode 100644
index 0000000000..0979a99ed7
--- /dev/null
+++ b/tools/lint/eslint/eslint-plugin-mozilla/tests/use-includes-instead-of-indexOf.js
@@ -0,0 +1,38 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// ------------------------------------------------------------------------------
+// Requirements
+// ------------------------------------------------------------------------------
+
+var rule = require("../lib/rules/use-includes-instead-of-indexOf");
+var RuleTester = require("eslint").RuleTester;
+
+const ruleTester = new RuleTester({ parserOptions: { ecmaVersion: "latest" } });
+
+// ------------------------------------------------------------------------------
+// Tests
+// ------------------------------------------------------------------------------
+
+function invalidCode(code) {
+  let message = "use .includes instead of .indexOf";
+  return { code, errors: [{ message, type: "BinaryExpression" }] };
+}
+
+ruleTester.run("use-includes-instead-of-indexOf", rule, {
+  valid: [
+    "let a = foo.includes(bar);",
+    "let a = foo.indexOf(bar) > 0;",
+    "let a = foo.indexOf(bar) != 0;",
+  ],
+  invalid: [
+    invalidCode("let a = foo.indexOf(bar) >= 0;"),
+    invalidCode("let a = foo.indexOf(bar) != -1;"),
+    invalidCode("let a = foo.indexOf(bar) !== -1;"),
+    invalidCode("let a = foo.indexOf(bar) == -1;"),
+    invalidCode("let a = foo.indexOf(bar) === -1;"),
+    invalidCode("let a = foo.indexOf(bar) < 0;"),
+  ],
+});