2 files changed, 35 insertions, 0 deletions
diff --git a/webAO/services/__tests__/downloadFile.test.ts b/webAO/services/__tests__/downloadFile.test.ts
new file mode 100644
index 0000000..b217b2c
--- /dev/null
+++ b/webAO/services/__tests__/downloadFile.test.ts
@@ -0,0 +1,27 @@
+import downloadFile from '../downloadFile'
+jest
+  .useFakeTimers()
+  .setSystemTime(new Date('2020-01-01').getTime());
+
+  global.URL.createObjectURL = jest.fn();
+(window as any).global.Blob = function (content, options){return  ({content, options})}
+
+describe('downloadFile', () => {
+    it('Creates an <a> tag', () => {
+        const createElementSpy = jest.spyOn(document, 'createElement');
+        downloadFile('hi', 'filename')
+        expect(createElementSpy).toBeCalled()
+    })
+    it('Creates the blob with the correct data', () => {
+        const data = 'writingtestsishard'
+        global.URL.createObjectURL = jest.fn(() => data);
+        downloadFile(data, 'filename')
+        const expected = {
+            content: [data],
+            options: {
+                type: "text"
+            }
+        }
+        expect(global.URL.createObjectURL).toBeCalledWith(expected)
+    })
+})
+\ No newline at end of file
diff --git a/webAO/services/downloadFile.ts b/webAO/services/downloadFile.ts
new file mode 100644
index 0000000..058075f
--- /dev/null
+++ b/webAO/services/downloadFile.ts
@@ -0,0 +1,8 @@
+const downloadFile = (content: string, filename: string) => {
+  const a = document.createElement('a');
+  const file = new Blob([content], {type: 'text'});
+  a.href= URL.createObjectURL(file);
+  a.download = filename;
+  a.click();
+}
+export default downloadFile
+\ No newline at end of file