Add StackBlitz example for macros

Author: SamVerschueren

.gitignore

@@ -3,3 +3,4 @@
 /node_modules/
 /test-tap/**/node_modules/
 /test/**/fixtures/**/node_modules/*/
+/examples/**/node_modules/

docs/01-writing-tests.md

@@ -290,6 +290,8 @@ console.log('Test file currently being run:', test.meta.file);
 
 ## Reusing test logic through macros
 
+[![Open in StackBlitz](https://developer.stackblitz.com/img/open_in_stackblitz.svg)](https://stackblitz.com/github/avajs/ava/tree/main/examples/macros?file=test.js&terminal=test&view=editor)
+
 Additional arguments passed to the test declaration will be passed to the test implementation. This is useful for creating reusable test macros.
 
 ```js

examples/macros/index.js

@@ -0,0 +1 @@
+exports.sum = (a, b) => a + b;

examples/macros/package.json

@@ -0,0 +1,10 @@
+{
+	"name": "ava-macros",
+	"description": "Example for reusing test logic through macros",
+	"scripts": {
+		"test": "ava"
+	},
+	"devDependencies": {
+		"ava": "^3.15.0"
+	}
+}

examples/macros/readme.md

@@ -0,0 +1,5 @@
+# Macros
+
+> Example for [reusing test logic through macros](https://github.com/avajs/ava/blob/main/docs/01-writing-tests.md#reusing-test-logic-through-macros)
+
+[![Open in StackBlitz](https://developer.stackblitz.com/img/open_in_stackblitz.svg)](https://stackblitz.com/github/avajs/ava/tree/main/examples/macros?file=test.js&terminal=test&view=editor)

examples/macros/test.js

@@ -0,0 +1,14 @@
+'use strict';
+const test = require('ava');
+
+const {sum} = require('.');
+
+function macro(t, a, b, expected) {
+	t.is(sum(a, b), expected);
+}
+
+macro.title = (providedTitle, a, b, expected) => `${providedTitle || ''} ${a}+${b} = ${expected}`.trim();
+
+test(macro, 2, 2, 4);
+test(macro, 3, 3, 6);
+test('providedTitle', macro, 4, 4, 8);