## Summary
Fixes a bug where `bun update --interactive` only updated `package.json`
but didn't actually install the updated packages. Users had to manually
run `bun install` afterwards.
## Root Cause
The bug was in `savePackageJson()` in
`src/cli/update_interactive_command.zig`:
1. The function wrote the updated `package.json` to disk
2. But it **didn't update the in-memory cache**
(`WorkspacePackageJSONCache`)
3. When `installWithManager()` ran, it called `getWithPath()` which
returned the **stale cached version**
4. So the installation proceeded with the old dependencies
## The Fix
Update the cache entry after writing to disk (line 116):
```zig
package_json.*.source.contents = new_package_json_source;
```
This matches the behavior in `updatePackageJSONAndInstall.zig` line 269.
## Test Plan
Added comprehensive regression tests in
`test/cli/update_interactive_install.test.ts`:
- ✅ Verifies that `package.json` is updated
- ✅ Verifies that `node_modules` is updated (this was failing before the
fix)
- ✅ Tests both normal update and `--latest` flag
- ✅ Compares installed version to confirm packages were actually
installed
Run tests with:
```bash
bun bd test test/cli/update_interactive_install.test.ts
```
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
