Fix: no-dupe-args to work with destructuring (fixes #2148)

eslint · Mar 27, 2015 · f9b0724 · f9b0724
1 parent 0653cf7
commit f9b0724
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Showing 2 changed files with 42 additions and 8 deletions.
diff --git a/lib/rules/no-dupe-args.js b/lib/rules/no-dupe-args.js
@@ -23,15 +23,45 @@ module.exports = function(context) {
      * @private
      */
     function checkParams(node) {
-        var dups = {};
+        var params = {},
+            dups = {};
+
+
+        /**
+         * Marks a given param as either seen or duplicated.
+         * @param {string} name The name of the param to mark.
+         * @returns {void}
+         * @private
+         */
+        function markParam(name) {
+            if (params.hasOwnProperty(name)) {
+                dups[name] = 1;
+            } else {
+                params[name] = 1;
+            }
+        }
 
         // loop through and find each duplicate param
-        node.params.map(function(param) {
-            return param.name;
-        }).forEach(function(param, i, params) {
-            var lastPos = params.lastIndexOf(param);
-            if (i !== lastPos) {
-                dups[param] = [i, lastPos];
+        node.params.forEach(function(param) {
+
+            switch (param.type) {
+                case "Identifier":
+                    markParam(param.name);
+                    break;
+
+                case "ObjectPattern":
+                    param.properties.forEach(function(property) {
+                        markParam(property.key.name);
+                    });
+                    break;
+
+                case "ArrayPattern":
+                    param.elements.forEach(function(element) {
+                        markParam(element.name);
+                    });
+                    break;
+
+                // no default
             }
         });
 

diff --git a/tests/lib/rules/no-dupe-args.js b/tests/lib/rules/no-dupe-args.js
@@ -21,10 +21,14 @@ var eslintTester = new ESLintTester(eslint);
 eslintTester.addRuleTest("lib/rules/no-dupe-args", {
     valid: [
         "function a(a, b, c){}",
-        "var a = function(a, b, c){}"
+        "var a = function(a, b, c){}",
+        { code: "function a({a, b}, {c, d}){}", ecmaFeatures: { destructuring: true } }
     ],
     invalid: [
         { code: "function a(a, b, b) {}", errors: [{ message: "Duplicate param 'b'." }] },
+        { code: "function a({a, b}, b) {}", ecmaFeatures: { destructuring: true }, errors: [{ message: "Duplicate param 'b'." }] },
+        { code: "function a([a, b], b) {}", ecmaFeatures: { destructuring: true }, errors: [{ message: "Duplicate param 'b'." }] },
+        { code: "function a([a, b], {b}) {}", ecmaFeatures: { destructuring: true }, errors: [{ message: "Duplicate param 'b'." }] },
         { code: "function a(a, a, a) {}", errors: [{ message: "Duplicate param 'a'." }] },
         { code: "function a(a, b, a) {}", errors: [{ message: "Duplicate param 'a'." }]},
         { code: "function a(a, b, a, b) {}", errors: [{ message: "Duplicate param 'a'." }, { message: "Duplicate param 'b'." }]},