packager: Module: tweak isHaste return type

Reviewed By: cpojer

Differential Revision: D5036181

fbshipit-source-id: 6042beb44bc67e64dd57c8dd6043f8dd690e9382

packages/metro-bundler/src/node-haste/AssetModule.js

@@ -37,7 +37,7 @@ class AssetModule extends Module {
   }
 
   isHaste() {
-    return Promise.resolve(false);
+    return false;
   }
 
   readCached(): CachedReadResult {

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

@@ -123,30 +123,32 @@ class HasteMap extends EventEmitter {
 
   _processHasteModule(file, previousName) {
     const module = this._moduleCache.getModule(file);
-    return module.isHaste().then(
-      isHaste => isHaste && module.getName()
+    return Promise.resolve().then(() => {
+      const isHaste = module.isHaste();
+      return isHaste && module.getName()
         .then(name => {
           const result = this._updateHasteMap(name, module);
           if (previousName && name !== previousName) {
             this.emit('change');
           }
           return result;
-        })
-    );
+        });
+    });
   }
 
   _processHastePackage(file, previousName) {
     const p = this._moduleCache.getPackage(file);
-    return p.isHaste()
-      .then(isHaste => isHaste && p.getName()
+    return Promise.resolve().then(() => {
+      const isHaste = p.isHaste();
+      return isHaste && p.getName()
         .then(name => {
           const result = this._updateHasteMap(name, p);
           if (previousName && name !== previousName) {
             this.emit('change');
           }
           return result;
-        }))
-      .catch(e => {
+        });
+    }).catch(e => {
       if (e instanceof SyntaxError) {
         // Malformed package.json.
         return;

packages/metro-bundler/src/node-haste/Module.js

@@ -133,8 +133,8 @@ class Module {
     this._readResultsByOptionsKey = new Map();
   }
 
-  isHaste(): Promise<boolean> {
-    return Promise.resolve().then(() => this._getHasteName() != null);
+  isHaste(): boolean {
+    return this._getHasteName() != null;
   }
 
   getCode(transformOptions: WorkerOptions) {

packages/metro-bundler/src/node-haste/Polyfill.js

@@ -32,7 +32,7 @@ class Polyfill extends Module {
   }
 
   isHaste() {
-    return Promise.resolve(false);
+    return false;
   }
 
   getName() {

packages/metro-bundler/src/node-haste/__tests__/Module-test.js

@@ -107,7 +107,7 @@ describe('Module', () => {
       );
 
       it('identifies the module as haste module', () =>
-        module.isHaste().then(isHaste => expect(isHaste).toBe(true))
+        expect(module.isHaste()).toBe(true)
       );
 
       it('does not transform the file in order to access the name', () => {
@@ -120,8 +120,8 @@ describe('Module', () => {
       it('does not transform the file in order to access the haste status', () => {
         const transformCode =
           jest.genMockFn().mockReturnValue(Promise.resolve());
-        return createModule({transformCode}).isHaste()
-          .then(() => expect(transformCode).not.toBeCalled());
+        createModule({transformCode}).isHaste();
+        expect(transformCode).not.toBeCalled();
       });
     });
 
@@ -135,7 +135,7 @@ describe('Module', () => {
       );
 
       it('does not identify the module as haste module', () =>
-        module.isHaste().then(isHaste => expect(isHaste).toBe(false))
+        expect(module.isHaste()).toBe(false)
       );
 
       it('does not transform the file in order to access the name', () => {
@@ -148,8 +148,8 @@ describe('Module', () => {
       it('does not transform the file in order to access the haste status', () => {
         const transformCode =
           jest.genMockFn().mockReturnValue(Promise.resolve());
-        return createModule({transformCode}).isHaste()
-          .then(() => expect(transformCode).not.toBeCalled());
+        createModule({transformCode}).isHaste();
+        expect(transformCode).not.toBeCalled();
       });
     });
   });