1 files changed, 108 insertions, 0 deletions
diff --git a/README.md b/README.md
index 6ae4673..36d1fed 100644
--- a/README.md
+++ b/README.md
@@ -30,6 +30,114 @@ or, run the test script
 
     ./run-test
 
+### Debugging a Jest integration test
+
+`page.test.js`
+
+```javascript
+// webdriver setup here
+
+it('loads the page', async () => {
+  await driver.get("http://localhost:3005");
+
+  expect(await driver.getTitle()).toEqual('Infantry Combat Solo Basic');
+
+  // where you want your breakpoint
+  debugger;
+
+  // necessary for restarting from the debugger to work
+  driver.quit();
+});
+```
+
+Start the container with a bash prompt.
+
+    docker run --rm --init -it -v $PWD:/usr/src/app btroops bash
+
+Start the debugger with Jest integration test setup
+
+    NODE_INSPECT_RESUME_ON_START=1 node inspect ./node_modules/jest/bin/jest.js --config jest.config.integ.cjs --runInBand test/integration/page.test.js
+
+You can do the whole thing in one command like this.
+
+    docker run --rm --init -it -v $PWD:/usr/src/app -e NODE_INSPECT_RESUME_ON_START=1 btroops node inspect ./node_modules/jest/bin/jest.js --config jest.config.integ.cjs --runInBand test/integration/page.test.js
+
+```
+< Debugger listening on ws://127.0.0.1:9229/bcaf4c18-b204-49c6-8ccf-600fe8be0506
+< For help, see: https://nodejs.org/en/docs/inspector
+<
+connecting to 127.0.0.1:9229 ... ok
+< Debugger attached.
+<
+< Jest config file read.
+<
+<
+< Spawning server process...
+<
+< Development server running at http://localhost:3005
+< Build completed in 10ms
+<
+<
+break in test/integration/page.test.js:26
+ 24   await counter.click();
+ 25   expect(await counter.getAttribute('class')).toEqual(expect.stringContaining('selected'));
+>26   debugger;
+ 27 });
+ 28 afterAll(() => driver.quit());
+debug>
+```
+
+To run the test again without having to quit the debugger, use `c` to continue past the breakpoint and then `r` to restart.
+
+```
+debug> c
+< PASS test/integration/page.test.js (141.892 s)
+<
+<   ✓ loads the page (8 ms)
+<
+<   ✓ selects a trooper by clicking on their counter (140792 ms)
+<
+<
+< Test Suites: 1 passed, 1 total
+< Tests:       2 passed, 2 total
+< Snapshots:   0 total
+< Time:        141.925 s
+< Ran all test suites matching /test\/integration\/page.test.js/i.
+<
+< Stopping server.
+<
+< Waiting for the debugger to disconnect...
+<
+debug> r
+< Debugger listening on ws://127.0.0.1:9229/9ba4c56c-03ff-46c4-92d1-3b519374d1be
+< For help, see: https://nodejs.org/en/docs/inspector
+<
+connecting to 127.0.0.1:9229 ... ok
+< Debugger attached.
+<
+< Jest config file read.
+<
+<
+< Spawning server process...
+<
+< Development server running at http://localhost:3005
+< Build completed in 11ms
+<
+<
+break in test/integration/page.test.js:26
+ 24   await counter.click();
+ 25   expect(await counter.getAttribute('class')).toEqual(expect.stringContaining('selected'));
+>26   debugger;
+ 27 });
+ 28 afterAll(() => driver.quit());
+debug>
+```
+
+### References
+
+https://nodejs.org/en/learn/getting-started/debugging
+https://nodejs.org/api/debugger.html
+
 ## Rough way to save the SVG map generated by JavaScript client-side
 
     const XMLS = new XMLSerializer();