Update dev doc

.github/DEVELOPMENT.md

@@ -36,35 +36,47 @@ There's a separate guide for [writing a plugin][5].
 ## Watcher
 
 ```shell
-cd packages/knip
 bun watch
 ```
 
 Changes in the source code are now automatically picked up, and `knip` is
 available globally to run from any directory.
 
+## Debugging
+
+### IDE
+
+- Open the Knip source repository
+- Set a breakpoint in Knip source code
+- In the built-in terminal, cd to your project
+- Enable e.g. "auto-attach" to Node.js process or "only attach with flag"
+- Run:
+
+```shell
+tsx --inspect path/to/knip/packages/knip/src/cli.ts
+```
+
 ## Fixtures & Tests
 
 Pull requests should include one or more tests. See the `tests` and `fixtures`
 directories to find relevant files that you may want to borrow or copy from.
 
-Let's assume you created `fixtures/feature` and `test/feature.test.ts`. Here's 4
-ways to run it:
+Assuming you've created `fixtures/feature` and `test/feature.test.ts`, from the
+`packages/knip` location, here's 4 ways to run it:
 
-### Run the test
+### 1. Run the test
 
 ```shell
 bun test ./test/feature.test.ts
 ```
 
-### Run Knip in the directory
+### 2. Run Knip in the directory
 
 ```shell
-cd fixtures/feature
-knip
+knip --directory fixtures/feature
 ```
 
-### Attach debugger to Node.js
+### 3. Attach debugger to Node.js
 
 Attach to Node.js process launched in terminal in IDE, and then:
 
@@ -73,21 +85,37 @@ cd fixtures/feature
 tsx --inspect ../../src/cli.ts
 ```
 
-### Attach debugger to Bun
+### 4. VS Code: Attach to Bun
 
-Set a breakpoint and start Knip with Bun while waiting for the debugger to be
-attached:
+- Install the
+  [VS Code Bun extension](https://marketplace.visualstudio.com/items?itemName=oven.bun-vscode)
+  if you haven't already
+- Set a breakpoint and start Knip with Bun while waiting for the debugger to be
+  attached:
 
 ```shell
 cd fixtures/feature
 bun --inspect-wait=127.0.0.1:6499/knip run ../../src/cli.ts
 ```
 
-Attach the debugger using the "Attach to Bun" launch configuration.
+Then run the "Attach to Bun" launch configuration.
+
+### 5. VS Code: Attach debugger to Bun from a test
+
+- Install the
+  [VS Code Bun extension](https://marketplace.visualstudio.com/items?itemName=oven.bun-vscode)
+  if you haven't already
+- Set a breakpoint and run the "Debug Bun test" launch configuration while in
+  any test file.
 
-### Attach debugger to Bun from a test
+### Attach debugger to tests
 
-Run the "Debug Bun test" launch configuration from any test file.
+In case you're wondering if/why some code is ever hit, it's possible to attach
+the debugger to each test. Set a breakpoint and run all tests (warning: slow):
+
+```shell
+tsx --inspect --test --import ./transform-test.js test/**/*.test.ts
+```
 
 ## QA
 

package.json

@@ -19,6 +19,7 @@
   "scripts": {
     "watch": "bun run --cwd packages/knip watch",
     "docs": "bun run --cwd packages/docs dev",
+    "test": "bun run --cwd packages/knip test",
     "format": "biome format .",
     "lint": "biome lint .",
     "ci": "biome ci . && installed-check --no-include-workspace-root --ignore-dev"