Sphinx Debug

Sphinx Debug

Quick Diagnostic Command

Run the build with maximum verbosity and pdb on exception:

make html SPHINXOPTS="-vv -T -P"

Flags:

• -vv: Verbose autodoc mock logging
• -T: Full traceback
• -P: Drop into pdb on exception

For agents: automate pdb via monkey-patch

If you are an agent and cannot interact with an interactive pdb session, do not redesign a subprocess/pty capture system. Instead, monkey-patch pdb.post_mortem so it runs scripted commands and prints the output directly to stdout.

Run this one-shot script from the docs directory (docs/en or docs/zh_cn):

cd docs/en   # or docs/zh_cn
python -c "
import pdb, sys, io, traceback

# Hijack pdb.post_mortem to auto-run diagnostic commands
_original_post_mortem = pdb.post_mortem

def scripted_post_mortem(tb=None):
    out = io.StringIO()
    p = pdb.Pdb(stdout=out, stdin=io.StringIO(''))
    p.use_rawinput = False
    p.reset()
    if tb is None:
        tb = sys.exc_info()[2]
    p.setup(None, tb)

    old_stderr = sys.stderr
    sys.stderr = out

    # List all inner exceptions
    p.onecmd('for i, exc in enumerate(exceptions): print(f\"[{i}] {type(exc).__name__}: {exc}\")')
    # Print full traceback of the first TypeError (the real root cause)
    p.onecmd('type_errs = [exc for exc in exceptions if type(exc).__name__ == \"TypeError\"]')
    p.onecmd('if type_errs: import traceback; traceback.print_exception(type(type_errs[0]), type_errs[0], type_errs[0].__traceback__)')
    p.do_quit('')

    sys.stderr = old_stderr
    print('=== PDB AUTOMATED OUTPUT ===')
    print(out.getvalue())
    print('=== END OUTPUT ===')

pdb.post_mortem = scripted_post_mortem

from sphinx.cmd.build import build_main
build_main(['-b', 'html', '-vv', '-T', '-P', '.', '_build/html'])
"

This runs the real Sphinx build with -P, but when pdb drops in it automatically executes your commands and dumps the results to stdout. You read the output exactly as if you had typed the pdb commands yourself.

What to look for in the automated output

Sphinx autosummary raises ImportExceptionGroup when it cannot resolve a module. The top-level message is often misleading (e.g. no module named xtuner.v1.ray.dataflow). The real root cause is hidden inside the grouped exceptions.

Common root-cause patterns

1. TypeError about __version__

   TypeError: expected string or bytes-like object, got '__version__'
   

   This happens when a mocked module (e.g. torch) is imported for real by an intermediate library (e.g. fla) that calls packaging.version.parse() on the mocked __version__ object.

   Fix: Add the intermediate library to autodoc_mock_imports in conf.py. To identify the exact library, read the traceback: the frame just above packaging/version.py is the culprit (e.g. fla/utils.py).

   autodoc_mock_imports = [
       ...
       "fla",   # or whatever library triggers the real import
   ]
   

2. Missing-comma string-concatenation bug

   If autodoc_mock_imports contains an entry like "scipytorchvision", a comma is missing between two string literals in conf.py:

   # WRONG
   autodoc_mock_imports = [
       ...
       "scipy"
       "torchvision",
       ...
   ]
   
   # CORRECT
   autodoc_mock_imports = [
       ...
       "scipy",
       "torchvision",
       ...
   ]
   

3. AttributeError after the TypeErrors

   AttributeError: module 'xtuner.v1.ray' has no attribute 'dataflow'
   

   This is usually a secondary failure caused by the earlier TypeErrors. Fix the TypeError first, then rebuild.

Step-by-step workflow

1. Run the automated pdb script (see "For agents" section above).
2. Read the === PDB AUTOMATED OUTPUT === block.
3. If you see TypeError: expected string or bytes-like object, got '__version__', read the traceback to find the intermediate library name.
4. Add the identified library to autodoc_mock_imports in both docs/en/conf.py and docs/zh_cn/conf.py.
5. Also eyeball autodoc_mock_imports for missing commas while you are there.
6. Re-run make html (without -P) to verify the fix.