Implementation of caching functionality for setup-go action (#228)

__tests__/cache-restore.test.ts

@@ -0,0 +1,86 @@
+import * as cache from '@actions/cache';
+import * as core from '@actions/core';
+import * as glob from '@actions/glob';
+
+import * as cacheRestore from '../src/cache-restore';
+import * as cacheUtils from '../src/cache-utils';
+import {PackageManagerInfo} from '../src/package-managers';
+
+describe('restoreCache', () => {
+  //Arrange
+  let hashFilesSpy = jest.spyOn(glob, 'hashFiles');
+  let getCacheDirectoryPathSpy = jest.spyOn(
+    cacheUtils,
+    'getCacheDirectoryPath'
+  );
+  let restoreCacheSpy = jest.spyOn(cache, 'restoreCache');
+  let infoSpy = jest.spyOn(core, 'info');
+  let setOutputSpy = jest.spyOn(core, 'setOutput');
+
+  const packageManager = 'default';
+  const cacheDependencyPath = 'path';
+
+  beforeEach(() => {
+    getCacheDirectoryPathSpy.mockImplementation(
+      (PackageManager: PackageManagerInfo) => {
+        return new Promise<string[]>(resolve => {
+          resolve(['cache_directory_path', 'cache_directory_path']);
+        });
+      }
+    );
+  });
+
+  it('should throw if dependency file path is not valid', async () => {
+    //Arrange
+    hashFilesSpy.mockImplementation((somePath: string) => {
+      return new Promise<string>(resolve => {
+        resolve('');
+      });
+    });
+
+    //Act + Assert
+    expect(async () => {
+      await cacheRestore.restoreCache(packageManager, cacheDependencyPath);
+    }).rejects.toThrowError(
+      'Some specified paths were not resolved, unable to cache dependencies.'
+    );
+  });
+
+  it('should inform if cache hit is not occured', async () => {
+    //Arrange
+    hashFilesSpy.mockImplementation((somePath: string) => {
+      return new Promise<string>(resolve => {
+        resolve('file_hash');
+      });
+    });
+
+    restoreCacheSpy.mockImplementation(() => {
+      return new Promise<string>(resolve => {
+        resolve('');
+      });
+    });
+
+    //Act + Assert
+    await cacheRestore.restoreCache(packageManager, cacheDependencyPath);
+    expect(infoSpy).toBeCalledWith(`Cache is not found`);
+  });
+
+  it('should set output if cache hit is occured', async () => {
+    //Arrange
+    hashFilesSpy.mockImplementation((somePath: string) => {
+      return new Promise<string>(resolve => {
+        resolve('file_hash');
+      });
+    });
+
+    restoreCacheSpy.mockImplementation(() => {
+      return new Promise<string>(resolve => {
+        resolve('cache_key');
+      });
+    });
+
+    //Act + Assert
+    await cacheRestore.restoreCache(packageManager, cacheDependencyPath);
+    expect(setOutputSpy).toBeCalledWith('cache-hit', true);
+  });
+});