From 462ff572b3cd2e1e1b1d3336c9fc718db3f68b7f Mon Sep 17 00:00:00 2001
From: Amjad Masad <amjad.masad@gmail.com>
Date: Tue, 12 May 2015 13:19:21 -0700
Subject: [PATCH 1/2] Add failing test for trailing commas in methods

---
 test/acorn/tests-babel.js | 59 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/test/acorn/tests-babel.js b/test/acorn/tests-babel.js
index 71cfa9813b..5b429aba26 100644
--- a/test/acorn/tests-babel.js
+++ b/test/acorn/tests-babel.js
@@ -3255,6 +3255,65 @@ test("function log(n, op, val,) { }", {
   features: { "es7.trailingFunctionCommas": true }
 });
 
+test("class Foo { bar(a,) { } }", {
+  type: "Program",
+  start: 0,
+  end: 25,
+  body: [{
+    type: "ClassDeclaration",
+    start: 0,
+    end: 25,
+    id: {
+      type: "Identifier",
+      name: "Foo",
+      start: 6,
+      end: 9
+    },
+    superClass: null,
+    body: {
+      type: "ClassBody",
+      start: 10,
+      end: 25,
+      body: [{
+        type: "MethodDefinition",
+        start: 12,
+        end: 23,
+        static: false,
+        key: {
+          type: "Identifier",
+          start: 12,
+          end: 15,
+          name: "bar"
+        },
+        kind: "method",
+        value: {
+          type: "FunctionExpression",
+          start: 15,
+          end: 23,
+          id: null,
+          params: [{
+            type: "Identifier",
+            name: "a",
+            start: 16,
+            end: 17
+          }],
+          generator: false,
+          body: {
+            type: "BlockStatement",
+            start: 20,
+            end: 23,
+            body: []
+          },
+          expression: false
+        }
+      }]
+    }
+  }]
+}, {
+  ecmaVersion: 7,
+  features: { "es7.trailingFunctionCommas": true }
+});
+
 testFail("log(,);", "Unexpected token (1:4)", {
   ecmaVersion: 7,
   features: { "es7.trailingFunctionCommas": true }

From 0452e0fdd216bc8db4cccd21f291ff84a8fb3e0f Mon Sep 17 00:00:00 2001
From: Amjad Masad <amjad.masad@gmail.com>
Date: Tue, 12 May 2015 13:20:36 -0700
Subject: [PATCH 2/2] Allow trailing commas in methods

---
 src/acorn/src/expression.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/acorn/src/expression.js b/src/acorn/src/expression.js
index 6b8e842e8d..b820a6bf64 100755
--- a/src/acorn/src/expression.js
+++ b/src/acorn/src/expression.js
@@ -635,7 +635,7 @@ pp.parseMethod = function(isGenerator, isAsync) {
   let node = this.startNode()
   this.initFunction(node, isAsync)
   this.expect(tt.parenL)
-  node.params = this.parseBindingList(tt.parenR, false, false)
+  node.params = this.parseBindingList(tt.parenR, false, this.options.features["es7.trailingFunctionCommas"])
   if (this.options.ecmaVersion >= 6) {
     node.generator = isGenerator
   }