From 0986ec525e941cb416c1f27355a0782a399a205f Mon Sep 17 00:00:00 2001
From: Don Jayamanne <don.jayamanne@yahoo.com>
Date: Tue, 13 Aug 2019 09:37:45 -0700
Subject: [PATCH] Throw error when unable to compute hash

---
 src/client/common/platform/fileSystem.ts         |  6 +++---
 src/client/common/platform/types.ts              |  2 +-
 src/test/common/platform/filesystem.unit.test.ts | 11 +++++++++++
 3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/src/client/common/platform/fileSystem.ts b/src/client/common/platform/fileSystem.ts
index 8e31446c4774..dede671d3fc6 100644
--- a/src/client/common/platform/fileSystem.ts
+++ b/src/client/common/platform/fileSystem.ts
@@ -146,11 +146,11 @@ export class FileSystem implements IFileSystem {
         return deferred.promise;
     }
 
-    public getFileHash(filePath: string): Promise<string | undefined> {
-        return new Promise<string | undefined>(resolve => {
+    public getFileHash(filePath: string): Promise<string> {
+        return new Promise<string>((resolve, reject) => {
             fs.lstat(filePath, (err, stats) => {
                 if (err) {
-                    resolve();
+                    reject(err);
                 } else {
                     const actual = createHash('sha512').update(`${stats.ctimeMs}-${stats.mtimeMs}`).digest('hex');
                     resolve(actual);
diff --git a/src/client/common/platform/types.ts b/src/client/common/platform/types.ts
index d14a5001cef1..aa0baa2e2aa5 100644
--- a/src/client/common/platform/types.ts
+++ b/src/client/common/platform/types.ts
@@ -56,7 +56,7 @@ export interface IFileSystem {
     getRealPath(path: string): Promise<string>;
     copyFile(src: string, dest: string): Promise<void>;
     deleteFile(filename: string): Promise<void>;
-    getFileHash(filePath: string): Promise<string | undefined>;
+    getFileHash(filePath: string): Promise<string>;
     search(globPattern: string): Promise<string[]>;
     createTemporaryFile(extension: string): Promise<TemporaryFile>;
     createWriteStream(path: string): fs.WriteStream;
diff --git a/src/test/common/platform/filesystem.unit.test.ts b/src/test/common/platform/filesystem.unit.test.ts
index 2e65335b057f..2100e0810d9a 100644
--- a/src/test/common/platform/filesystem.unit.test.ts
+++ b/src/test/common/platform/filesystem.unit.test.ts
@@ -9,6 +9,7 @@ import { FileSystem } from '../../../client/common/platform/fileSystem';
 import { IFileSystem, IPlatformService, TemporaryFile } from '../../../client/common/platform/types';
 // tslint:disable-next-line:no-require-imports no-var-requires
 const assertArrays = require('chai-arrays');
+use(require('chai-as-promised'));
 use(assertArrays);
 
 // tslint:disable-next-line:max-func-body-length
@@ -116,4 +117,14 @@ suite('FileSystem', () => {
                 });
         });
     });
+    test('Getting hash for non existent file should throw error', async () => {
+        const promise = fileSystem.getFileHash('some unknown file');
+
+        await expect(promise).to.eventually.be.rejected;
+    });
+    test('Getting hash for a file should return non-empty string', async () => {
+        const hash = await fileSystem.getFileHash(__filename);
+
+        expect(hash).to.be.length.greaterThan(0);
+    });
 });