babylon: throw parse error if class properties do not have a semicolon (fixes T6873)

src/parser/statement.js

@@ -594,7 +594,7 @@ pp.parseClass = function (node, isStatement, optionalId) {
 };
 
 pp.isClassProperty = function () {
-  return this.match(tt.eq) || this.isLineTerminator();
+  return this.match(tt.eq) || this.match(tt.semi) || this.canInsertSemicolon();
 };
 
 pp.parseClassBody = function (node) {
@@ -746,7 +746,9 @@ pp.parseClassProperty = function (node) {
   } else {
     node.value = null;
   }
-  this.semicolon();
+  if (!this.eat(tt.semi)) {
+    this.raise(this.state.start, "A semicolon is required after a class property");
+  }
   return this.finishNode(node, "ClassProperty");
 };
 

test/fixtures/experimental/class-properties/semicolons-required-with-value/actual.js

@@ -0,0 +1,3 @@
+class A {
+  asdf = 1
+}

test/fixtures/experimental/class-properties/semicolons-required-with-value/options.json

@@ -0,0 +1,4 @@
+{
+  "throws": "A semicolon is required after a class property (3:0)",
+  "plugins": ["classProperties"]
+}

test/fixtures/experimental/class-properties/semicolons-required-without-value/actual.js

@@ -0,0 +1,3 @@
+class A {
+  asdf
+}

test/fixtures/experimental/class-properties/semicolons-required-without-value/options.json

@@ -0,0 +1,4 @@
+{
+  "throws": "A semicolon is required after a class property (3:0)",
+  "plugins": ["classProperties"]
+}