From eb691425b60be4354f8be86d56b4bb3135c73614 Mon Sep 17 00:00:00 2001
From: Daniel Tschinder <daniel@tschinder.de>
Date: Fri, 29 Jul 2016 20:22:49 +0200
Subject: [PATCH] Only allow declares inside declare module (#73)

* Only allow declares inside declare module

* Better error message
---
 src/parser/util.js                               | 8 ++++----
 src/plugins/flow.js                              | 3 +--
 test/fixtures/flow/declare-module/8/actual.js    | 3 +++
 test/fixtures/flow/declare-module/8/options.json | 3 +++
 4 files changed, 11 insertions(+), 6 deletions(-)
 create mode 100644 test/fixtures/flow/declare-module/8/actual.js
 create mode 100644 test/fixtures/flow/declare-module/8/options.json

diff --git a/src/parser/util.js b/src/parser/util.js
index c8cdeda9f1..992e3432ca 100644
--- a/src/parser/util.js
+++ b/src/parser/util.js
@@ -45,8 +45,8 @@ pp.eatContextual = function (name) {
 
 // Asserts that following token is given contextual keyword.
 
-pp.expectContextual = function (name) {
-  if (!this.eatContextual(name)) this.unexpected();
+pp.expectContextual = function (name, message) {
+  if (!this.eatContextual(name)) this.unexpected(null, message);
 };
 
 // Test whether a semicolon can be inserted at the current position.
@@ -79,6 +79,6 @@ pp.expect = function (type) {
 
 // Raise an unexpected token error.
 
-pp.unexpected = function (pos) {
-  this.raise(pos != null ? pos : this.state.start, "Unexpected token");
+pp.unexpected = function (pos, message = "Unexpected token") {
+  this.raise(pos != null ? pos : this.state.start, message);
 };
diff --git a/src/plugins/flow.js b/src/plugins/flow.js
index cbad58e5ea..4a61599ba1 100644
--- a/src/plugins/flow.js
+++ b/src/plugins/flow.js
@@ -102,8 +102,7 @@ pp.flowParseDeclareModule = function (node) {
   while (!this.match(tt.braceR)) {
     let node2 = this.startNode();
 
-    // todo: declare check
-    this.next();
+    this.expectContextual("declare", "Unexpected token. Only declares are allowed inside declare module");
 
     body.push(this.flowParseDeclare(node2));
   }
diff --git a/test/fixtures/flow/declare-module/8/actual.js b/test/fixtures/flow/declare-module/8/actual.js
new file mode 100644
index 0000000000..093f9927d9
--- /dev/null
+++ b/test/fixtures/flow/declare-module/8/actual.js
@@ -0,0 +1,3 @@
+declare module A {
+  declar var a:number
+}
diff --git a/test/fixtures/flow/declare-module/8/options.json b/test/fixtures/flow/declare-module/8/options.json
new file mode 100644
index 0000000000..ae5e7790e2
--- /dev/null
+++ b/test/fixtures/flow/declare-module/8/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Unexpected token. Only declares are allowed inside declare module (2:2)"
+}