Replace removed pkgutil.get_loader with importlib.util.find_spec in get_fullname by Copilot · Pull Request #1998 · microsoft/debugpy

Copilot · 2026-02-23T17:37:27Z

pkgutil.get_loader() was removed in Python 3.14, causing get_fullname() to silently return None for all module lookups. When subProcess: true, debugpy intercepts subprocess calls and uses get_fullname() to resolve -m <module> targets. The silent failure cascades to "No module named ..." for any single-file module run via subprocess.run([sys.executable, "-m", "mod"]).

Changes

pydevd_file_utils.py: Replace pkgutil.get_loader() with importlib.util.find_spec(), checking spec.has_location to exclude built-in/frozen module origins (e.g. "built-in", "frozen") that aren't file paths
test_convert_utilities.py: Add regression test for get_fullname() covering single-file modules, packages, and nonexistent modules

# Before (broken on 3.14+)
def get_fullname(mod_name):
    import pkgutil
    try:
        loader = pkgutil.get_loader(mod_name)  # AttributeError on 3.14
    except:
        return None
    ...

# After
def get_fullname(mod_name):
    try:
        import importlib.util
        spec = importlib.util.find_spec(mod_name)
        if spec is not None and spec.origin is not None and spec.has_location:
            return spec.origin
    except (ImportError, ModuleNotFoundError, ValueError):
        pass
    return None

Original prompt

This section details on the original issue you should resolve

<issue_title>Unable to run a Python module in a subprocess when subProcess: true</issue_title>
<issue_description>The following script executes a Python module in a subprocess.
# main.py
import subprocess
import sys

subprocess.run([sys.executable, "-m", "sub"])
# sub.py
print("Hello, world!")
// launch.json
{
    "version": "0.2.0",
    "configurations": [
    
        {
            "name": "Python Debugger: Current File",
            "type": "debugpy",
            "request": "launch",
            "program": "${file}",
            "console": "integratedTerminal",
            "subProcess": true,
        }
    ]
}
Running this in the debugger with "subProcess": true fails:
bash-3.2$  cd /Users/pete/projects/subprocess_test ; /usr/bin/env /Users/pete/projects/subprocess_test/.venv/bin/python /Users/pete/.vscode/extensions/ms-python.debugpy-2025.18.0-darwin-arm64/bundled/libs/debugpy/adapter/../../debugpy/launcher 56894 -- /Users/pete/projects/subprocess_test/main.py 
No module named sub
Running it with "subProcess": false works as expected:
bash-3.2$  cd /Users/pete/projects/subprocess_test ; /usr/bin/env /Users/pete/projects/subprocess_test/.venv/bin/python /Users/pete/.vscode/extensions/ms-python.debugpy-2025.18.0-darwin-arm64/bundled/libs/debugpy/adapter/../../debugpy/launcher 57618 -- /Users/pete/projects/subprocess_test/main.py 
Hello, world!
OS: Darwin arm64 25.3.0
VSCode: 1.109.5 (Universal)
Python Debugger: 2025.18.0
Python: 3.14.2 (in a virtualenv)</issue_description>

<agent_instructions>I can reproduce this problem. You'll likely need to write a test that reproduces the issue and then add logging to debugpy to figure out why it can find the 'sub' module.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

Fixes Unable to run a Python module in a subprocess when subProcess: true #1997

🔒 GitHub Advanced Security automatically protects Copilot coding agent pull requests. You can protect all pull requests by enabling Advanced Security for your repositories. Learn more about Advanced Security.

…kgutil.get_loader pkgutil.get_loader() was removed in Python 3.14, causing subprocess module execution to fail with "No module named" when subProcess: true. Replace with importlib.util.find_spec() which is the recommended replacement and works across all supported Python versions. Co-authored-by: rchiodo <19672699+rchiodo@users.noreply.github.com>

rchiodo · 2026-02-23T17:55:27Z

/azp run

azure-pipelines · 2026-02-23T17:55:38Z

Azure Pipelines successfully started running 1 pipeline(s).

This MR contains the following updates: | Package | Type | Update | Change | OpenSSF | |---|---|---|---|---| | [debugpy](https://aka.ms/debugpy) ([source](https://github.com/microsoft/debugpy)) | dev | patch | `1.8.20` → `1.8.21` | [![OpenSSF Scorecard](https://api.securityscorecards.dev/projects/github.com/microsoft/debugpy/badge)](https://securityscorecards.dev/viewer/?uri=github.com/microsoft/debugpy) | | [numpy](https://github.com/numpy/numpy) ([changelog](https://numpy.org/doc/stable/release)) | dependencies | patch | `2.4.4` → `2.4.6` | [![OpenSSF Scorecard](https://api.securityscorecards.dev/projects/github.com/numpy/numpy/badge)](https://securityscorecards.dev/viewer/?uri=github.com/numpy/numpy) | | [pydantic-settings](https://github.com/pydantic/pydantic-settings) ([changelog](https://github.com/pydantic/pydantic-settings/releases)) | dependencies | patch | `2.14.0` → `2.14.2` | [![OpenSSF Scorecard](https://api.securityscorecards.dev/projects/github.com/pydantic/pydantic-settings/badge)](https://securityscorecards.dev/viewer/?uri=github.com/pydantic/pydantic-settings) | | [python-multipart](https://github.com/Kludex/python-multipart) ([changelog](https://github.com/Kludex/python-multipart/blob/master/CHANGELOG.md)) | dependencies | patch | `^0.0.22` → `^0.0.32` | [![OpenSSF Scorecard](https://api.securityscorecards.dev/projects/github.com/Kludex/python-multipart/badge)](https://securityscorecards.dev/viewer/?uri=github.com/Kludex/python-multipart) | | [types-requests](https://github.com/python/typeshed) ([changelog](https://github.com/typeshed-internal/stub_uploader/blob/main/data/changelogs/requests.md)) | dependencies | patch | `2.32.0.20240523` → `2.32.4.20260324` | [![OpenSSF Scorecard](https://api.securityscorecards.dev/projects/github.com/python/typeshed/badge)](https://securityscorecards.dev/viewer/?uri=github.com/python/typeshed) | --- ### Release Notes <details> <summary>microsoft/debugpy (debugpy)</summary> ### [`v1.8.21`](https://github.com/microsoft/debugpy/releases/tag/v1.8.21): debugpy v1.8.21 [Compare Source](microsoft/debugpy@v1.8.20...v1.8.21) Fixes for: - Return evaluate result in DAP response body instead of writing to stdout: [#2027](microsoft/debugpy#2027) - Prevent invalid `scopes` request from crashing debug session: [#2026](microsoft/debugpy#2026) - Skip uninitialized `__slots__` in variable resolver: [#2024](microsoft/debugpy#2024) - Handle `-c` arguments that are `bytes` instead of `str`: [#2021](microsoft/debugpy#2021) - Fix evaluation of variables from chained exception frames: [#2018](microsoft/debugpy#2018) - `ContinueRequest` with a specific `threadId` no longer resumes all threads (in-process adapter): [#2012](microsoft/debugpy#2012) - Avoid strong reference to exceptions during unwind: [#2008](microsoft/debugpy#2008) - Show error message on evaluate failures in the hover context: [#2006](microsoft/debugpy#2006) - Display `dlerror` output when `dlopen` fails: [#2000](microsoft/debugpy#2000) - Replace removed `pkgutil.get_loader` with `importlib.util.find_spec` in `get_fullname`: [#1998](microsoft/debugpy#1998) Enhancements: - Add option to ignore all system exit codes: [#2017](microsoft/debugpy#2017) - Pull changes from pydevd up to March 2026: [#2010](microsoft/debugpy#2010) Infrastructure work: - Suppress Flawfinder false positives on Cython memcpy / read-loop iterators (TSA [#2816216](https://github.com/microsoft/debugpy/issues/2816216), [#2816217](https://github.com/microsoft/debugpy/issues/2816217), [#2816218](https://github.com/microsoft/debugpy/issues/2816218), [#2816219](https://github.com/microsoft/debugpy/issues/2816219), [#2816220](https://github.com/microsoft/debugpy/issues/2816220)): [#2028](microsoft/debugpy#2028), [#2029](microsoft/debugpy#2029), [#2030](microsoft/debugpy#2030), [#2031](microsoft/debugpy#2031), [#2032](microsoft/debugpy#2032) Thanks to [@maxbachmann](https://github.com/maxbachmann), [@mfussenegger](https://github.com/mfussenegger), and [@sambrightman](https://github.com/sambrightman) for the commits. </details> <details> <summary>numpy/numpy (numpy)</summary> ### [`v2.4.6`](https://github.com/numpy/numpy/releases/tag/v2.4.6): (May 18, 2026) [Compare Source](numpy/numpy@v2.4.5...v2.4.6) ### NumPy 2.4.6 Release Notes NumPy 2.4.6 is a quick release that fixes a regression discovered in the 2.4.5 release. This release supports Python versions 3.11-3.14 #### Contributors A total of 4 people contributed to this release. People with a "+" by their names contributed a patch for the first time. - !EarlMilktea - Charles Harris - Sebastian Berg - Warren Weckesser #### Pull requests merged A total of 4 pull requests were merged for this release. - [#31444](numpy/numpy#31444): MAINT: Prepare 2.4.x for further development - [#31453](numpy/numpy#31453): BUG: Fix regression in `arr.conj()` - [#31459](numpy/numpy#31459): BUG: `np.linalg.svd(..., hermitian=True)` returns non-unitary... - [#31460](numpy/numpy#31460): BUG: Don't call INCREF/DECREF on descr in NpyStringAcquireAllocator... ### [`v2.4.5`](https://github.com/numpy/numpy/releases/tag/v2.4.5): (May 15, 2026) [Compare Source](numpy/numpy@v2.4.4...v2.4.5) ### NumPy 2.4.5 Release Notes NumPy 2.4.5 is a patch release that fixes bugs discovered after the 2.4.4 release, has some typing improvements, and maintains infrastructure. This release supports Python versions 3.11-3.14 #### Contributors A total of 17 people contributed to this release. People with a "+" by their names contributed a patch for the first time. - Aleksei Nikiforov - Anarion Zuo + - Ankit Ahlawat - Breno Favaretto + - Charles Harris - Igor Krivenko + - Ijtihed Kilani + - Joren Hammudoglu - Maarten Baert + - Matti Picus - Nathan Goldbaum - Praneeth Kodumagulla + - Ralf Gommers - RoomWithOutRoof + - Sebastian Berg - Warren Weckesser - div + #### Pull requests merged A total of 28 pull requests were merged for this release. - [#31093](numpy/numpy#31093): MAINT: Prepare 2.4.x for further development - [#31182](numpy/numpy#31182): TYP: fix `np.shape` assignability issue for python lists ([#31171](numpy/numpy#31171)) - [#31197](numpy/numpy#31197): ENH: Return rank 0 for empty matrices in matrix\_rank ([#30422](numpy/numpy#30422)) - [#31198](numpy/numpy#31198): CI/BUG: add native jobs for s390x, fix bug in `pack_inner`... - [#31199](numpy/numpy#31199): BUG: f2py map complex\_long\_double to NPY\_CLONGDOUBLE - [#31205](numpy/numpy#31205): MAINT: f2py: Stop setting re.\_MAXCACHE to 50. - [#31206](numpy/numpy#31206): BUG: fix heap buffer overflow in timedelta to string casts - [#31207](numpy/numpy#31207): MAINT: Rename ppc64le and s390x workflow ([#31121](numpy/numpy#31121)) - [#31208](numpy/numpy#31208): BUG: Fix matvec/vecmat in-place aliasing (out=input produces... - [#31209](numpy/numpy#31209): TYP: `tile`: accept numpy scalars and arrays as second argument... - [#31211](numpy/numpy#31211): DEP: Undo deprecation for np.dtype() signature used by old pickles... - [#31212](numpy/numpy#31212): REV: Manual revert of float16 svml use ([#31178](numpy/numpy#31178)) - [#31222](numpy/numpy#31222): TYP: `ix_` fix for boolean and non-1d input ([#31218](numpy/numpy#31218)) - [#31329](numpy/numpy#31329): BUG: incorrect temp elision for new-style (NEP 43) user-defined... - [#31330](numpy/numpy#31330): TYP: fix sliding\_window\_view axis parameter typing - [#31335](numpy/numpy#31335): BUG: Prevent deadlock due to downstream importing NumPy in dlopen... - [#31336](numpy/numpy#31336): BUG: Fix segfault in nditer.multi\_index when \_\_getitem\_\_ raises... - [#31338](numpy/numpy#31338): TYP: Fix ruff lint error - [#31357](numpy/numpy#31357): BUG: fix memory leak in np.zeros when fill-zero loop raises ([#31320](numpy/numpy#31320)) - [#31358](numpy/numpy#31358): BUG: np.einsum() fails with a 0-dimensional out argument and... - [#31379](numpy/numpy#31379): BUG: Fix signed overflow issue in npy\_gcd for INT\_MIN on s390x... - [#31383](numpy/numpy#31383): CI: remove Cirrus CI FreeBSD job ([#31380](numpy/numpy#31380)) - [#31390](numpy/numpy#31390): BUILD: newer MKL uses so.3 - [#31391](numpy/numpy#31391): BLD/MAINT: improve support for Intel LLVM compilers - [#31401](numpy/numpy#31401): BUG: Avoid UB in [safe]()\[add,sub,mul] helpers ([#31396](numpy/numpy#31396)) - [#31402](numpy/numpy#31402): BUG: exclude \_\_pycache\_\_ directories from wheels ([#31397](numpy/numpy#31397)) - [#31404](numpy/numpy#31404): TYP: `_NestedSequence` type parameter default to work around... - [#31426](numpy/numpy#31426): TYP: Fix `DTypeLike` runtime type-checker support ([#31425](numpy/numpy#31425)) </details> <details> <summary>pydantic/pydantic-settings (pydantic-settings)</summary> ### [`v2.14.2`](https://github.com/pydantic/pydantic-settings/releases/tag/v2.14.2) [Compare Source](pydantic/pydantic-settings@v2.14.1...v2.14.2) #### What's Changed This is a security patch release. - Prevent `NestedSecretsSettingsSource` from following symlinks outside `secrets_dir` by [@hramezani](https://github.com/hramezani) in [#889](pydantic/pydantic-settings#889) - Prepare release 2.14.2 by [@hramezani](https://github.com/hramezani) in [#890](pydantic/pydantic-settings#890) ##### Security Fixes [GHSA-4xgf-cpjx-pc3j](GHSA-4xgf-cpjx-pc3j): `NestedSecretsSettingsSource` with `secrets_nested_subdir=True` could follow a symbolic link inside `secrets_dir` pointing outside it, reading out-of-tree files into settings values and bypassing the `secrets_dir_max_size` cap. Affected versions: `>= 2.12.0, < 2.14.2`. **Full Changelog**: <pydantic/pydantic-settings@v2.14.1...v2.14.2> ### [`v2.14.1`](https://github.com/pydantic/pydantic-settings/releases/tag/v2.14.1) [Compare Source](pydantic/pydantic-settings@v2.14.0...v2.14.1) #### What's Changed - Bump the python-packages group with 4 updates by [@dependabot](https://github.com/dependabot)\[bot] in [#850](pydantic/pydantic-settings#850) - Bump the python-packages group with 5 updates by [@dependabot](https://github.com/dependabot)\[bot] in [#854](pydantic/pydantic-settings#854) - Bump the github-actions group with 3 updates by [@dependabot](https://github.com/dependabot)\[bot] in [#853](pydantic/pydantic-settings#853) - Bump the python-packages group with 2 updates by [@dependabot](https://github.com/dependabot)\[bot] in [#856](pydantic/pydantic-settings#856) - Fix field named `cls` conflicting with classmethod parameter by [@hramezani](https://github.com/hramezani) in [#858](pydantic/pydantic-settings#858) - Prepare release 2.14.1 by [@hramezani](https://github.com/hramezani) in [#859](pydantic/pydantic-settings#859) **Full Changelog**: <pydantic/pydantic-settings@v2.14.0...v2.14.1> </details> <details> <summary>Kludex/python-multipart (python-multipart)</summary> ### [`v0.0.32`](https://github.com/Kludex/python-multipart/blob/HEAD/CHANGELOG.md#0032-2026-06-04) [Compare Source](Kludex/python-multipart@0.0.31...0.0.32) - Speed up partial-boundary scanning for CR/LF-dense part data [#300](Kludex/python-multipart#300). ### [`v0.0.31`](https://github.com/Kludex/python-multipart/blob/HEAD/CHANGELOG.md#0031-2026-06-04) [Compare Source](Kludex/python-multipart@0.0.30...0.0.31) - Speed up multipart header parsing and callback dispatch [#295](Kludex/python-multipart#295). - Bound header field name size before validating [#296](Kludex/python-multipart#296). - Validate `Content-Length` is non-negative in `parse_form` [#297](Kludex/python-multipart#297). ### [`v0.0.30`](https://github.com/Kludex/python-multipart/blob/HEAD/CHANGELOG.md#0030-2026-05-31) [Compare Source](Kludex/python-multipart@0.0.29...0.0.30) - Parse `application/x-www-form-urlencoded` bodies per the WHATWG URL standard, treating only `&` as a field separator [#290](Kludex/python-multipart#290). - Ignore RFC 2231/5987 extended parameters (`name*`, `filename*`) in `parse_options_header`, keeping the plain parameter authoritative per [RFC 7578 §4.2](https://datatracker.ietf.org/doc/html/rfc7578#section-4.2) [#291](Kludex/python-multipart#291). ### [`v0.0.29`](https://github.com/Kludex/python-multipart/blob/HEAD/CHANGELOG.md#0029-2026-05-17) [Compare Source](Kludex/python-multipart@0.0.28...0.0.29) - Handle malformed RFC 2231 continuations in `parse_options_header` [#270](Kludex/python-multipart#270). ### [`v0.0.28`](https://github.com/Kludex/python-multipart/blob/HEAD/CHANGELOG.md#0028-2026-05-10) [Compare Source](Kludex/python-multipart@0.0.27...0.0.28) - Speed up partial-boundary tail scan via `bytes.find` [#281](Kludex/python-multipart#281). - Cap multipart boundary length at 256 bytes [#282](Kludex/python-multipart#282). ### [`v0.0.27`](https://github.com/Kludex/python-multipart/blob/HEAD/CHANGELOG.md#0027-2026-04-27) [Compare Source](Kludex/python-multipart@0.0.26...0.0.27) - Add multipart header limits [#267](Kludex/python-multipart#267). - Pass parse offsets via constructors [#268](Kludex/python-multipart#268). ### [`v0.0.26`](https://github.com/Kludex/python-multipart/blob/HEAD/CHANGELOG.md#0026-2026-04-10) [Compare Source](Kludex/python-multipart@0.0.25...0.0.26) - Skip preamble before the first multipart boundary more efficiently [#262](Kludex/python-multipart#262). - Silently discard epilogue data after the closing multipart boundary [#259](Kludex/python-multipart#259). ### [`v0.0.25`](https://github.com/Kludex/python-multipart/blob/HEAD/CHANGELOG.md#0025-2026-04-10) [Compare Source](Kludex/python-multipart@0.0.24...0.0.25) - Add MIME content type info to `File` [#143](Kludex/python-multipart#143). - Handle CTE values case-insensitively [#258](Kludex/python-multipart#258). - Remove custom `FormParser` classes [#257](Kludex/python-multipart#257). - Add `UPLOAD_DELETE_TMP` to `FormParser` config [#254](Kludex/python-multipart#254). - Emit `field_end` for trailing bare field names on finalize [#230](Kludex/python-multipart#230). - Handle multipart headers case-insensitively [#252](Kludex/python-multipart#252). - Apply Apache-2.0 properly [#247](Kludex/python-multipart#247). ### [`v0.0.24`](https://github.com/Kludex/python-multipart/blob/HEAD/CHANGELOG.md#0024-2026-04-05) [Compare Source](Kludex/python-multipart@0.0.23...0.0.24) - Validate `chunk_size` in `parse_form()` [#244](Kludex/python-multipart#244). ### [`v0.0.23`](https://github.com/Kludex/python-multipart/blob/HEAD/CHANGELOG.md#0023-2026-04-05) [Compare Source](Kludex/python-multipart@0.0.22...0.0.23) - Remove unused `trust_x_headers` parameter and `X-File-Name` fallback [#196](Kludex/python-multipart#196). - Return processed length from `QuerystringParser._internal_write` [#229](Kludex/python-multipart#229). - Cleanup metadata dunders from `__init__.py` [#227](Kludex/python-multipart#227). </details> --- - [ ] If you want to rebase/retry this MR, check this box --- This MR has been generated by [Mend Renovate](https://github.com/renovatebot/renovate).  See merge request swiss-armed-forces/cyber-command/cea/loom!460 Co-authored-by: Loom MR Pipeline Trigger <group_103951964_bot_9504bb8dead6d4e406ad817a607f24be@noreply.gitlab.com> Co-authored-by: shrewd-laidback palace <shrewd-laidback-palace-736-c41-2c1-e464fc974@swiss-armed-forces-open-source.ch>

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6aefe5f

Copilot AI assigned Copilot and rchiodo Feb 23, 2026

Copilot started work on behalf of rchiodo February 23, 2026 17:38 View session

Copilot AI changed the title ~~[WIP] Fix inability to run Python module in subprocess~~ Replace removed pkgutil.get_loader with importlib.util.find_spec in get_fullname Feb 23, 2026

Copilot AI requested a review from rchiodo February 23, 2026 17:54

Copilot finished work on behalf of rchiodo February 23, 2026 17:54

rchiodo marked this pull request as ready for review February 23, 2026 17:56

rchiodo requested a review from a team as a code owner February 23, 2026 17:56

rchiodo approved these changes Feb 23, 2026

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StellaHuang95 approved these changes Feb 23, 2026

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rchiodo merged commit bc6fe51 into main Feb 23, 2026
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Replace removed pkgutil.get_loader with importlib.util.find_spec in get_fullname#1998

Replace removed pkgutil.get_loader with importlib.util.find_spec in get_fullname#1998
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