Use "getSha1" from HasteFS

Reviewed By: cpojer

Differential Revision: D7721378

fbshipit-source-id: 441666df325c60d94eb6e14b50c3c4cde76b3dfe

packages/metro/src/node-haste/DependencyGraph.js

@@ -219,14 +219,7 @@ class DependencyGraph extends EventEmitter {
   }
 
   getSha1(filename: string): string {
-    // $FlowFixMe: TODO T27501330: Use getSha1 from HasteFS.
-    const file = this._hasteFS._files[filename];
-
-    if (!file) {
-      throw new ReferenceError(`File ${filename} is not tracked by haste-map`);
-    }
-
-    const sha1 = file[4];
+    const sha1 = this._hasteFS.getSha1(filename);
 
     if (!sha1) {
       throw new ReferenceError(`SHA-1 for file ${filename} is not computed`);

packages/metro/src/node-haste/types.js

@@ -15,5 +15,6 @@ export type HasteFS = {
   exists(filePath: string): boolean,
   getAllFiles(): Array<string>,
   getModuleName(filePath: string): ?string,
+  getSha1(string): ?string,
   matchFiles(pattern: RegExp | string): Array<string>,
 };