Fix #1534: Handle None response from LLM in PptxConverter#1569
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cobyfrombrooklyn-bot wants to merge 1 commit intomicrosoft:mainfrom
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Fix #1534: Handle None response from LLM in PptxConverter#1569cobyfrombrooklyn-bot wants to merge 1 commit intomicrosoft:mainfrom
cobyfrombrooklyn-bot wants to merge 1 commit intomicrosoft:mainfrom
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When llm_caption() returns None (e.g., LLM returns null content), the join on line 139 raises TypeError because str.join cannot handle NoneType items. Added 'or ""' fallback so None is coerced to empty string, matching the initialized default. Added test_pptx_llm_returns_none that mocks an LLM client returning None content and verifies conversion completes without TypeError.
zashed
approved these changes
Feb 27, 2026
zashed
approved these changes
Feb 27, 2026
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Fixes #1534
Problem
When an LLM client returns
Noneas the message content (e.g., content filtering, API errors, or unexpected responses),PptxConvertercrashes with:This happens on line 139 of
_pptx_converter.pywhere"\n".join([llm_description, alt_text])is called, butllm_descriptionisNone(returned byllm_caption()which has return typeUnion[None, str]).Fix
Added
or ""fallback afterllm_caption()call so that aNonereturn is coerced to empty string, matching the initialized default on line 98. This is a 4-character change.Test
Added
test_pptx_llm_returns_noneintest_module_misc.pythat:Nonecontenttest.pptxwith the mock clientTest fails without the fix (TypeError), passes with it.
Tested locally on macOS ARM (Apple Silicon). Full test suite: 145 passed, 7 skipped/failed (pre-existing, due to missing optional deps like youtube-transcript-api).