4 Commits
Author SHA1 Message Date
Joyee Cheung f30139e3b9 debugger: add more logs to probe mode
Add more log points in the probe mode and enable the debuglog
int the probe mode tests.

Signed-off-by: Joyee Cheung <joyeec9h3@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/63663
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Kohei Ueno <kohei.ueno119@gmail.com>
2026-06-01 20:36:47 +00:00
Joyee Cheung ee11c35a3e debugger: disambiguate probe location binding
In probe mode, `--probe utils.js:10` can match multiple scripts
(e.g. `src/utils.js` and `lib/utils.js`) because the matcher uses
a path-separator-anchored URL suffix (similar to how e.g. gdb/lldb
behaves). Previously the report echoed only the user's request in
hit events, so a user seeing two hits at `utils.js:10` could not
tell which script each hit came from. In addition, previously
when the column was omitted we bound to 1 which was technically
different from how CDP binds omitted columns (to the first
executable column on the line).

This patch clarifies the semantics by tracking the scripts via
`Debugger.scriptParsed`, as recommended in the CDP docs, and
reports the actual execution location as `results[i].location`.
The same shape can be reused in the future for source maps or
additional events in attach mode.

This bumps the schema version because `target` is now
`{ suffix, line, column? }` instead of a positional array for
clarity. We picked `suffix` as the field name in case we
introduce other matching modes in the future. `column` is
omitted when the user did not supply one, and the actual
resolved column is reported in the hit event instead.

This patch also adds more tests for column-specific bindings,
multi-location resolution via require(cjs), and late script
binding via dynamic import(cjs) and require(esm).

Signed-off-by: Joyee Cheung <joyeec9h3@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/63286
Reviewed-By: Jan Martin <jan.krems@gmail.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
2026-05-15 16:59:19 +00:00
Joyee Cheung 78bbee385b debugger: add --help to node inspect and improve docs
- Add `--help` / `-h` to `node inspect` covering both interactive and
  non-interactive probe modes. The help text is printed when
  `--help`/`-h` appears before any positional argument to avoid
  hijacking `--help` passed to a child script.
- Improve the documentation of probe mode and add examples, explain
  same-location probe coalescing, TDZ caveat for let/const bindings,
  basename matching and exit code behavior. Also move it to a
  section parallel to interactive mode. Remove recommendation of
  evaluating structured expressions as that is prone to missing
  info in JSON mode.

Drive-by: When probe mode exits due to invalid arguments, exit with
`kInvalidCommandLineArgument` (9) instead of `kGenericUserError` (1).

Signed-off-by: Joyee Cheung <joyeec9h3@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/63201
Reviewed-By: Jan Martin <jan.krems@gmail.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
Reviewed-By: Aviv Keller <me@aviv.sh>
2026-05-11 21:54:19 +00:00
Joyee Cheung a79e224eb2 debugger: add edit-free runtime expression probes to node inspect
Add a non-interactive probe mode to `node inspect` for inspecting
runtime values in a run-to-completion application. This allows
users to perform printf-style debugging without having to modify
the application code and clean up afterwards, it also supports
structured output to be consumed by tools.

Probe mode launches the application, sets one or more source
breakpoints, evaluates one expression at each hit, and prints a
single text or JSON report when execution ends.

Interface:

node inspect [--json] [--preview] [--timeout=<ms>] [--port=<port>]
  --probe <file>:<line>[:<col>] --expr <expr> ...
  [--] <script> [args...]

Example:

```js
// cli.js
let maxRSS = 0;
for (let i = 0; i < 2; i++) {
  const { rss } = process.memoryUsage();
  maxRSS = Math.max(maxRSS, rss);
}
```

```
$ node inspect --probe cli.js:5 --expr 'rss' cli.js
Hit 1 at cli.js:5
  rss = 54935552
Hit 2 at cli.js:5
  rss = 55083008
Completed
```

(Prettified JSON to fit in commit message restrictions).

```js
$ node inspect --json --probe cli.js:5 --expr 'rss' cli.js
{"v":1,"probes":[{"expr":"rss","target":["cli.js",5]}],
"results":[
  {"probe":0,"event":"hit","hit":1,
   "result":{"type":"number","value":55443456,
             "description":"55443456"}},
  {"probe":0,"event":"hit","hit":2,
   "result":{"type":"number","value":55574528,
             "description":"55574528"}},
  {"event":"completed"}]}
```

Signed-off-by: Joyee Cheung <joyeec9h3@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/62713
Reviewed-By: Jan Martin <jan.krems@gmail.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
2026-04-19 15:59:10 +00:00