Add per-field cache invalidation

Summary:
Jest needs this for efficient caching of resolution responses.

public

Reviewed By: voideanvalue

Differential Revision: D2873291

fb-gh-sync-id: fee27d2ffdfe64bd68fdb4d9e4259e721b33631f

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

@@ -303,4 +303,33 @@ describe('Cache', () => {
         });
     });
   });
+
+  describe('invalidate', () => {
+    it('invalidates the cache per file or per-field', () => {
+      fs.stat.mockImpl((file, callback) =>
+        callback(null, {
+          mtime: {
+            getTime: () => {},
+          },
+        })
+      );
+
+      var cache = new Cache({
+        cacheKey: 'cache',
+      });
+      var loaderCb = jest.genMockFn().mockImpl(() =>
+        Promise.resolve('banana')
+      );
+      var file = '/rootDir/someFile';
+
+      return cache.get(file, 'field', loaderCb).then(() => {
+        expect(cache.has(file)).toBe(true);
+        cache.invalidate(file, 'field');
+        expect(cache.has(file)).toBe(true);
+        expect(cache.has(file, 'field')).toBe(false);
+        cache.invalidate(file);
+        expect(cache.has(file)).toBe(false);
+      });
+    });
+  });
 });

react-packager/src/DependencyResolver/Cache/index.js

@@ -58,9 +58,13 @@ class Cache {
     return recordP.then(record => record);
   }
 
-  invalidate(filepath) {
-    if (this.has(filepath)) {
-      delete this._data[filepath];
+  invalidate(filepath, field) {
+    if (this.has(filepath, field)) {
+      if (field == null) {
+        delete this._data[filepath];
+      } else {
+        delete this._data[filepath].data[field];
+      }
     }
   }
 
@@ -70,7 +74,7 @@ class Cache {
 
   has(filepath, field) {
     return Object.prototype.hasOwnProperty.call(this._data, filepath) &&
-      (!field || Object.prototype.hasOwnProperty.call(this._data[filepath].data, field));
+      (field == null || Object.prototype.hasOwnProperty.call(this._data[filepath].data, field));
   }
 
   _set(filepath, field, loaderPromise) {

react-packager/src/DependencyResolver/DependencyGraph/index.js

@@ -59,7 +59,7 @@ class DependencyGraph {
       mocksPattern,
       extractRequires,
       shouldThrowOnUnresolvedErrors,
-      transformCode
+      transformCode,
     };
     this._cache = cache;
     this._helpers = new DependencyGraphHelpers(this._opts);