New: Adding rule no-only (fixes #11)

docs/rules/no-only.md

@@ -0,0 +1,29 @@
+# Forbid the use of QUnit.only (no-only)
+
+`QUnit.only` is useful for restricting a test run to just one test while developing, but committing a test file using this function to a repository is dangerous because it will ensure that the rest of the test suite is not run.
+
+## Rule Details
+
+The following patterns are considered warnings:
+
+```js
+
+QUnit.only('Name', function () { });
+
+```
+
+The following patterns are not considered warnings:
+
+```js
+
+QUnit.test('Name', function () { });
+
+```
+
+## When Not to Use It
+
+If your development pipeline would make running this rule annoying, it could be safely disabled. However, it would be a good idea to ensure that this rule is run in continuous integration at the very least.
+
+## Further Reading
+
+* [QUnit.only](https://api.qunitjs.com/QUnit.only/)

index.js

@@ -6,13 +6,15 @@ module.exports = {
         "no-async-in-loops": require("./lib/rules/no-async-in-loops"),
         "no-commented-tests": require("./lib/rules/no-commented-tests"),
         "no-ok-equality": require("./lib/rules/no-ok-equality"),
+        "no-only": require("./lib/rules/no-only"),
         "resolve-async": require("./lib/rules/resolve-async")
     },
     rulesConfig: {
         "no-assert-equal": 0,
         "no-async-in-loops": 1,
         "no-commented-tests": 0,
         "no-ok-equality": 1,
+        "no-only": 1,
         "resolve-async": 2
     }
 };

lib/rules/no-only.js

@@ -0,0 +1,41 @@
+/**
+ * @fileoverview Forbid the use of QUnit.only.
+ * @author Kevin Partington
+ */
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+var utils = require("../utils");
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = function (context) {
+    var MESSAGE = "Unexpected QUnit.only call.";
+
+    function isQUnitOnly (calleeNode) {
+        return calleeNode &&
+            calleeNode.type === "MemberExpression" &&
+            calleeNode.object &&
+            calleeNode.object.type === "Identifier" &&
+            calleeNode.object.name === "QUnit" &&
+            calleeNode.property &&
+            calleeNode.property.type === "Identifier" &&
+            calleeNode.property.name === "only";
+    }
+
+    return {
+        "CallExpression": function (node) {
+            if (isQUnitOnly(node.callee)) {
+                context.report({
+                    node: node,
+                    message: MESSAGE
+                });
+            }
+        }
+    };
+};

tests/lib/rules/no-only.js

@@ -0,0 +1,36 @@
+/**
+ * @fileoverview Forbid the use of QUnit.only.
+ * @author Kevin Partington
+ */
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+var rule = require("../../../lib/rules/no-only"),
+    RuleTester = require("eslint").RuleTester;
+
+//------------------------------------------------------------------------------
+// Tests
+//------------------------------------------------------------------------------
+
+var ruleTester = new RuleTester();
+
+ruleTester.run("no-only", rule, {
+    valid: [
+        "QUnit.test('Name', function() { });",
+
+        // QUnit.only is not exposed globally so this is valid
+        "only('Name', function() { });"
+    ],
+
+    invalid: [
+        {
+            code: "QUnit.only('Name', function() { });",
+            errors: [
+                "Unexpected QUnit.only call."
+            ]
+        }
+    ]
+});