Debug serially in the "Debugging tests with VS Code" recipe (#1634)

Author: troysandal

docs/recipes/debugging-with-vscode.md

@@ -33,3 +33,22 @@ Save this configuration after you added it.
 Set breakpoints in the code **or** write `debugger;` at the point where it should stop.
 
 Hit the green `Debug` button next to the list of configurations on the top left in the `Debug` view. Once the breakpoint is hit, you can evaluate variables and step through the code.
+
+## Serial debugging
+
+By default AVA runs tests concurrently. This may complicate debugging. Add a configuration with the `--serial` argument so AVA runs only one test at a time:
+
+```json
+{
+	"type": "node",
+	"request": "launch",
+	"name": "Run AVA test serially",
+	"program": "${workspaceRoot}/node_modules/ava/profile.js",
+	"args": [
+	  "--serial",
+	  "${file}"
+	]
+}
+```
+
+*Note that, if your tests aren't properly isolated, certain test failures may not appear when running the tests serially.*