fix #861 : Verify file download

cypress/e2e/actions.spec.ts

@@ -3,6 +3,7 @@ describe('Check actions', () => {
 		cy.clearLocalStorage();
 		cy.visit('/edit');
 	});
+
 	it('should update markdown code', () => {
 		cy.get('#markdown')
 			.invoke('val')
@@ -21,4 +22,33 @@ describe('Check actions', () => {
 		cy.contains('Load Gist').click();
 		cy.contains('Go shopping!!');
 	});
+
+	it('should download png and svg', () => {
+		const now = new Date(2022, 0, 1).getTime();
+		cy.clock(now);
+		const downloadsFolder = Cypress.config('downloadsFolder');
+
+		const verifyFileSize = (fileType: string, size: number) => {
+			cy.get(`#download${fileType.toUpperCase()}`).click();
+			const fileName = `mermaid-diagram-2022-01-01-000000.${fileType}`;
+			const filePath = `${downloadsFolder}/${fileName}`;
+			cy.verifyDownload(fileName);
+			cy.readFile(filePath, null, {
+				log: false
+			}).then((buffer) => expect((buffer as ArrayBuffer).byteLength).to.be.gt(size));
+			cy.task('deleteFile', filePath);
+		};
+
+		verifyFileSize('png', 21_000);
+		verifyFileSize('svg', 11_000);
+
+		// Verify downloaded file is different for different diagrams
+		cy.contains('Sample Diagrams').click();
+		cy.contains('ER Diagram').click();
+
+		verifyFileSize('png', 46_000);
+		verifyFileSize('svg', 12_000);
+
+		cy.clock().invoke('restore');
+	});
 });

cypress/snapshots.js

@@ -16,7 +16,7 @@ module.exports = {
       "1": "{\"code\":\"graph TD\\n    A[Party] -->|Get money| B(Go shopping!!)\\n    \",\"mermaid\":\"{\\n  \\\"theme\\\": \\\"forest\\\",\\n  \\\"test\\\": \\\"hello world\\\"\\n}\",\"updateEditor\":false,\"autoSync\":true,\"updateDiagram\":true,\"loader\":{\"type\":\"files\",\"config\":{\"codeURL\":\"https://gist.githubusercontent.com/sidharthv96/6268a23e673a533dcb198f241fd7012a/raw/4eb03887e6a41397e80bdcdbf94017c498f8f1e2/code.mmd\",\"configURL\":\"https://gist.githubusercontent.com/sidharthv96/6268a23e673a533dcb198f241fd7012a/raw/4eb03887e6a41397e80bdcdbf94017c498f8f1e2/config.json\"}}}"
     }
   },
-  "__version": "10.0.3",
+  "__version": "10.2.0",
   "Auto sync tests": {
     "should dim diagram when code is edited": {
       "1": "{\"code\":\"graph TD\\n    A[Christmas] -->|Get money| B(Go shopping)\\n    B --> C{Let me think}\\n    C -->|One| D[Laptop]\\n    C -->|Two| E[iPhone]\\n    C -->|Three| F[fa:fa-car Car]\\n    C --> Test\",\"mermaid\":\"{\\n  \\\"theme\\\": \\\"default\\\"\\n}\",\"updateEditor\":false,\"autoSync\":false,\"updateDiagram\":false}"

cypress/support/e2e.js

@@ -15,6 +15,7 @@
 
 // Import commands.js using ES2015 syntax:
 import './commands';
+require('cy-verify-downloads').addCustomCommand();
 
 // Alternatively you can use CommonJS syntax:
 // require('./commands')

cypress/tsconfig.json

@@ -1,7 +1,7 @@
 {
 	"compilerOptions": {
 		"allowJs": true,
-		"types": ["cypress", "cypress-localstorage-commands"]
+		"types": ["cypress", "cypress-localstorage-commands", "cy-verify-downloads"]
 	},
 	"include": ["**/*.ts"]
 }