Description
rich.cells.chop_cells() emits a spurious empty first line when the very first character of the text is wider than max_cells.
Reproduction
from rich.cells import chop_cells
chop_cells("文", 1)
# actual: ['', '文']
# expected: ['文']Reproduced on rich 15.0.0 (and current master, rich/cells.py).
The root cause: the loop flushes the current (still empty) line whenever the next character does not fit. When the first character is a double-width CJK glyph and max_cells is 1, the buffer is flushed while empty, producing a leading "" entry. Any consumer that renders line-by-line (e.g. text wrapping into width-1 or narrow columns containing CJK text) shows a blank line before the content.
Non-degenerate case for contrast — this one is already correct:
chop_cells("ab文cd", 2) # ['ab', '文', 'cd'] ✅Proposed solution
In the flush branch, only append the buffered line if it is non-empty (one-line guard). A character that can never fit still gets emitted on its own line, matching the behavior of the "ab文cd" case above. I have this fix ready with two regression tests (red on current master, green with the fix; full test suite passes, black/mypy clean) and can open a PR if the approach is approved, per AI_POLICY.md.
Platform
Not platform-specific (pure Python, reproduced on Windows 11 / Python 3.11 / rich 15.0.0 and master).
Disclosure per the spirit of AI_POLICY.md: this bug was found and the fix prepared with the assistance of an AI agent (Claude Code), operated and reviewed by me. If the solution is approved by a maintainer, the follow-up PR will identify itself as AI-generated as the policy requires.
Description
rich.cells.chop_cells()emits a spurious empty first line when the very first character of the text is wider thanmax_cells.Reproduction
Reproduced on rich 15.0.0 (and current
master,rich/cells.py).The root cause: the loop flushes the current (still empty) line whenever the next character does not fit. When the first character is a double-width CJK glyph and
max_cellsis 1, the buffer is flushed while empty, producing a leading""entry. Any consumer that renders line-by-line (e.g. text wrapping into width-1 or narrow columns containing CJK text) shows a blank line before the content.Non-degenerate case for contrast — this one is already correct:
Proposed solution
In the flush branch, only append the buffered line if it is non-empty (one-line guard). A character that can never fit still gets emitted on its own line, matching the behavior of the
"ab文cd"case above. I have this fix ready with two regression tests (red on current master, green with the fix; full test suite passes,black/mypyclean) and can open a PR if the approach is approved, perAI_POLICY.md.Platform
Not platform-specific (pure Python, reproduced on Windows 11 / Python 3.11 / rich 15.0.0 and master).
Disclosure per the spirit of
AI_POLICY.md: this bug was found and the fix prepared with the assistance of an AI agent (Claude Code), operated and reviewed by me. If the solution is approved by a maintainer, the follow-up PR will identify itself as AI-generated as the policy requires.