Replace custom rolled stable string hashing with library

Reviewed By: cpojer

Differential Revision: D2937202

fb-gh-sync-id: dc08547c71da2bc35cfad108e63fd5e87f0ba734
shipit-source-id: dc08547c71da2bc35cfad108e63fd5e87f0ba734

react-packager/src/DependencyResolver/Module.js

@@ -11,6 +11,7 @@
 const crypto = require('crypto');
 const docblock = require('./DependencyGraph/docblock');
 const isAbsolutePath = require('absolute-path');
+const jsonStableStringify = require('json-stable-stringify');
 const path = require('path');
 const extractRequires = require('./lib/extractRequires');
 
@@ -206,29 +207,15 @@ function whileInDocBlock(chunk, i, result) {
 const knownHashes = new WeakMap();
 function stableObjectHash(object) {
   let digest = knownHashes.get(object);
-
   if (!digest) {
-    const hash = crypto.createHash('md5');
-    stableObjectHash.addTo(object, hash);
-    digest = hash.digest('base64');
+    digest = crypto.createHash('md5')
+      .update(jsonStableStringify(object))
+      .digest('base64');
     knownHashes.set(object, digest);
   }
 
   return digest;
 }
-stableObjectHash.addTo = function addTo(value, hash) {
-  if (value === null || typeof value !== 'object') {
-    hash.update(JSON.stringify(value));
-  } else {
-    Object.keys(value).sort().forEach(key => {
-      const valueForKey = value[key];
-      if (valueForKey !== undefined) {
-        hash.update(key);
-        addTo(valueForKey, hash);
-      }
-    });
-  }
-};
 
 function cacheKey(field, transformOptions) {
   return transformOptions !== undefined

react-packager/src/DependencyResolver/__tests__/Module-test.js

@@ -10,6 +10,7 @@
 
 jest
   .dontMock('absolute-path')
+  .dontMock('json-stable-stringify')
   .dontMock('../fastfs')
   .dontMock('../lib/extractRequires')
   .dontMock('../lib/replacePatterns')