Forbid semicolons after decorators in classes (#352)

src/parser/statement.js

@@ -648,6 +648,9 @@ pp.parseClassBody = function (node) {
 
   while (!this.eat(tt.braceR)) {
     if (this.eat(tt.semi)) {
+      if (decorators.length > 0) {
+        this.raise(this.state.lastTokEnd, "Decorators must not be followed by a semicolon");
+      }
       continue;
     }
 

test/fixtures/experimental/decorators/no-semi/actual.js

@@ -0,0 +1,4 @@
+class A {
+  @a;
+  m(){}
+}

test/fixtures/experimental/decorators/no-semi/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Decorators must not be followed by a semicolon (2:5)"
+}