feat(text): add shrink_text_to_fit method for dynamic font resizing#1107
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yahya09
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@BastienGimbert can you share an example of the |
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I'm in holiday rn , i will send and example next week. |
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Comment: I'm not sure I'd even want to use that: Consistency between slides and indeed text shapes suggests to me I wouldn't. But maybe there's a different perspective. |
MHoroszowski
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…epic (#59) Resolves all 11 sub-features of the issue #16 epic on one branch. Fork-state probe confirmed none existed here (unlike #18's arrowheads); this is genuinely all-new text-API surface. Maintainer UAT pending. New API: - Font.superscript / Font.subscript — a:rPr/@baseline (signed ST_Percentage fraction: +0.30 super, -0.25 sub; mutually exclusive). - Font.strike — MSO_TEXT_STRIKE_TYPE (NONE/SINGLE/DOUBLE -> noStrike/sngStrike/dblStrike), a:rPr/@strike. - Font.highlight — lazy _HighlightColor proxy over a:rPr/a:highlight (CT_Color); read-without-mutate, schema-ordered before the typeface trio (verified: [solidFill, highlight, latin, ea, cs]). - Font.character_spacing / Font.kerning — a:rPr/@spc (signed) and @kern (non-negative), centipoints like Font.size. - Font.latin / Font.east_asian / Font.complex_script — a:rPr a:latin/ a:ea/a:cs trio. Font.name STILL sets ONLY a:latin (backward compat, regression-tested). - TextFrame.columns / TextFrame.column_spacing — a:bodyPr @numcol (1..16, ValueError otherwise) / @spcCol (EMU). - TextFrame.text_direction — MSO_TEXT_DIRECTION enum, a:bodyPr/@Vert. - Paragraph.rtl — a:pPr/@rtl (Arabic/Hebrew/Persian; PowerPoint shapes). - TextFrame.will_overflow() / TextFrame.overflow_info() — read-only (does NOT mutate txBody or set autofit; ISC-68-verified) structured _OverflowInfo report via TextFitter. Closes scanny#1114. - TextFrame.shrink_text_to_fit() — eager normAutofit fontScale (thousandths form, e.g. "11111"); does not rewrite run sz. Adds CT_TextNormalAutofit/@lnSpcReduction. Closes scanny#1107. - fit_text long-word crash fix (scanny#168): _break_line now force-accepts the shortest candidate when no line fits a single word wider than the frame, instead of returning None and crashing _wrap_lines on a None unpack. New simpletypes (ST_TextPoint/ST_TextNonNegativePoint/ ST_TextColumnCount), enums (MSO_TEXT_STRIKE_TYPE, MSO_TEXT_DIRECTION), oxml registrations (a:highlight->CT_Color, a:ea/a:cs->CT_TextFont). All new a:rPr/a:bodyPr/a:pPr children/attrs are XSD-ordered (dml-main.xsd ground truth); autofit choice exclusivity verified. Tests: 47 new unit tests in tests/test_issue16_advanced_text.py (super/sub 5, strike 4, highlight 4, spacing 4, trio 5, columns 4, direction 4, rtl 4, overflow 5, shrink 3, fit168 3) + 11 behave scenarios. Per-attr save->reopen round-trip coverage included. Trinity (verbatim): python3 -m pytest tests/ -q -> 3972 passed (3925 + 47) ruff check src tests -> All checks passed! python3 -m behave features/ --no-color -> 1130 scenarios, 0 failed (1119 + 11) UAT: uat/uat_issue16_advanced_text.py runs clean, 15/15 round-trip checks, exit 0 (fixture includes the scanny#168 long unbreakable word and a latin+ea+cs+Arabic multi-script run per the UAT-fixture-diversity discipline). No-repair = directly observed: real PowerPoint loaded the deck as a named 4-slide presentation with zero modal sheets (no repair dialog) across multiple clean relaunches, no crash. Visual rendering of the slides is DEFERRED — PowerPoint's document window would not surface to screen/AX this session (an intermittent PowerPoint-side environment wall the #18 screenshot-probe documented; not a file defect). Visual + PowerPoint-resave preservation are the maintainer's §6a acceptance surface; not claimed here. Closes #16
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Problem & Solution: Text Autofit in python-pptx
The Problem
When you set
text_frame.auto_size = MSO_AUTO_SIZE.TEXT_TO_FIT_SHAPEin python-pptx, it only sets the XML flag (a:normAutofit). PowerPoint is supposed to recalculate the font size when opening the file, but it doesn't do it automatically - you have to manually open the file and activate/deactivate the functionality to trigger the resize.The Solution
I added a new method
shrink_text_to_fit()to theTextFrameclass that:TextFitterclassdefRPr)TEXT_TO_FIT_SHAPEflag so PowerPoint continues to auto-adjust if text is modified laterUsage
Files Modified
src/pptx/text/text.pyshrink_text_to_fit()methodsrc/pptx/text/layout.pyI also added an unit test to, that pass.