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Nov 14, 2017
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Docs: How to Debug Unit Tests #2992

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docs: adding section about debugging tests
mattmorgis Aug 22, 2017
abc6143
docs: removing node-inspector references
mattmorgis Aug 31, 2017
b03b7b1
docs: replacing terminal command with npm script
mattmorgis Sep 3, 2017
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Update README.md
Timer Nov 14, 2017
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docs: removing node-inspector references
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@mattmorgis
mattmorgis committed Aug 31, 2017
commit abc6143637b160053468f5c57bb826b7c3b5e255
16 changes: 5 additions & 11 deletions packages/react-scripts/template/README.md
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Expand Up @@ -1484,13 +1484,7 @@ If you use [Visual Studio Code](https://code.visualstudio.com), there is a [Jest

There are various ways to setup a debugger for your Jest tests. We cover debugging in Chrome and Visual Studio Code.

### Chrome & Node Inspector

Download [Node Inspector](https://github.com/node-inspector/node-inspector) or similar debugger

```bash
npm install -g node-inspector
```
### Chrome

Place `debugger;` statements in any test and run

Expand All @@ -1506,12 +1500,12 @@ node node_modules/bin/react-scripts --inspect-brk test --runInBand --testPathIgn

This will start running your Jest tests, but pause before executing to allow a debugger to attach to the process.

To attach the `node-inspector` debugger, run:
Open the following in Chrome
```
node-inspector
about:inspect
```

This will output a link that you can open in Chrome. After opening that link, the Chrome Developer Tools will be displayed, and a breakpoint will be set at the first line of the Jest CLI script (this is done simply to give you time to open the developer tools and to prevent Jest from executing before you have time to do so). Click the button that looks like a "play" button in the upper right hand side of the screen to continue execution. When Jest executes the test that contains the debugger statement, execution will pause and you can examine the current scope and call stack.
After opening that link, the Chrome Developer Tools will be displayed. Select `inspect` on your process and a breakpoint will be set at the first line of the react script (this is done simply to give you time to open the developer tools and to prevent Jest from executing before you have time to do so). Click the button that looks like a "play" button in the upper right hand side of the screen to continue execution. When Jest executes the test that contains the debugger statement, execution will pause and you can examine the current scope and call stack.

>Note: the --runInBand cli option makes sure Jest runs test in the same process rather than spawning processes for individual tests. Normally Jest parallelizes test runs across processes but it is hard to debug many processes at the same time.

Expand All @@ -1528,7 +1522,7 @@ Use the following [`launch.json`](https://code.visualstudio.com/docs/editor/debu
"name": "Debug CRA Tests",
"type": "node",
"request": "launch",
"runtimeExecutable": "${workspaceRoot/node_modules/.bin/react-scripts",
"runtimeExecutable": "${workspaceRoot}/node_modules/.bin/react-scripts",
"runtimeArgs": [
"--inspect-brk",
"test"
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