Merge pull request #200 from apollostack/memoize-gql

Memoize gql parse results

CHANGELOG.md

@@ -5,6 +5,7 @@ Expect active development and potentially significant breaking changes in the `0
 ### vNEXT
 
 - Improve error message when a dev forgets `gql` to link to docs. [PR #181](https://github.com/apollostack/apollo-client/pull/181)
+- Memoize results from `gql`, so that we save time on parsing, and we can use `===` to compare queries for performance. [Issue #199](https://github.com/apollostack/apollo-client/issues/199) [PR #200](https://github.com/apollostack/apollo-client/pull/200)
 - ...
 
 

src/gql.ts

@@ -4,13 +4,21 @@ import {
   Document,
 } from 'graphql';
 
+const cache: {[queryString: string]: Document} = {};
+
 function parseDocument(doc: string): Document {
+  if (cache[doc]) {
+    return cache[doc];
+  }
+
   const parsed = parse(doc);
 
   if (!parsed || parsed.kind !== 'Document') {
     throw new Error('Not a valid GraphQL document.');
   }
 
+  cache[doc] = parsed;
+
   return parsed as Document;
 }
 

test/gql.ts

@@ -0,0 +1,13 @@
+import { assert } from 'chai';
+
+import gql from '../src/gql';
+
+describe('gql', () => {
+  it('parses queries', () => {
+    assert.equal(gql`{ testQuery }`.kind, 'Document');
+  });
+
+  it('returns the same object for the same query', () => {
+    assert.isTrue(gql`{ sameQuery }` === gql`{ sameQuery }`);
+  });
+});

test/tests.ts

@@ -17,3 +17,4 @@ import './QueryManager';
 import './client';
 import './middleware';
 import './store';
+import './gql';