Fixes #1 Allow for multiple artifacts

__tests__/ArtifactUploader.test.ts

@@ -0,0 +1,43 @@
+import { Artifact } from "../src/Artifact"
+import { GithubArtifactUploader } from "../src/ArtifactUploader"
+import { Releases } from "../src/Releases";
+
+const artifacts = [
+    new Artifact('a/art1'),
+    new Artifact('b/art2')
+]
+const fileContents = Buffer.from('artful facts', 'utf-8')
+const contentLength = 42
+const uploadMock = jest.fn()
+const url = 'http://api.example.com'
+
+jest.mock('fs', () => {
+    return {
+        readFileSync: () => fileContents,
+        statSync: () => { return { size: contentLength } }
+    };
+})
+
+describe('ArtifactUploader', () => {
+    it('uploads artifacts', () => {
+        const uploader = createUploader()
+        
+        uploader.uploadArtifacts(artifacts, url)
+        
+        expect(uploadMock).toBeCalledTimes(2)
+        expect(uploadMock)
+            .toBeCalledWith(url, contentLength, 'raw', fileContents, 'art1')
+        expect(uploadMock)
+            .toBeCalledWith(url, contentLength, 'raw', fileContents, 'art2')
+    })
+
+    function createUploader(): GithubArtifactUploader {
+        const MockReleases = jest.fn<Releases, any>(() => {
+            return {
+                create: jest.fn(),
+                uploadArtifact: uploadMock
+            }
+        })
+        return new GithubArtifactUploader(new MockReleases())
+    }
+});