M4: a text style made from a whole layer counts a trailing empty paragraph's wrap style (#2094 review)

`paragraph_style` compared the paragraphs `para_span` gives for the whole text, which leaves
out an empty paragraph after a final newline, so Balance paragraphs over an Auto trailing one
made a Balance style. It now compares every paragraph by index, as the list style does. The
parity row says the wrap styles are lost through a .fig round trip.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Model-Effort: Opus 5.5 drove and wrote

crates/doc/src/text.rs

@@ -945,7 +945,9 @@ impl TextData {
             Some(first) if self.paragraphs.iter().all(|p| p.list == first.list) => first.list,
             _ => self.list,
         };
-        let wrap_style = self.common_wrap_style(0, self.char_count()).unwrap_or(self.wrap_style);
+        // Every paragraph by index: `para_span` leaves out an empty one after a final newline.
+        let first = self.para_wrap_style(0);
+        let wrap_style = if (1..self.paragraph_count()).all(|p| self.para_wrap_style(p) == first) { first } else { self.wrap_style };
         ParagraphStyle {
             paragraph_spacing: self.paragraph_spacing,
             paragraph_indent: self.paragraph_indent,
@@ -1259,4 +1261,16 @@ mod whole_text_paragraph_style_tests {
         plain.take_paragraph_style(&ps);
         assert_eq!((plain.list, plain.paragraphs.len()), (t.list, t.paragraphs.len()));
     }
+
+    #[test]
+    fn a_style_made_from_the_whole_layer_counts_a_trailing_empty_paragraphs_wrap_style() {
+        // The first two paragraphs are Balance, the empty one after the final newline keeps the
+        // layer's Auto: they differ, so the style takes the layer's wrap style, not Balance.
+        let mut t = TextData::new("a\nb\n");
+        t.set_para_wrap_styles(0, 3, WrapStyle::Balance);
+        assert_eq!((t.para_wrap_style(0), t.para_wrap_style(1), t.para_wrap_style(2)), (WrapStyle::Balance, WrapStyle::Balance, WrapStyle::Auto));
+        assert_eq!(t.paragraph_style().wrap_style, WrapStyle::Auto);
+        t.set_para_wrap_styles(4, 4, WrapStyle::Balance);
+        assert_eq!(t.paragraph_style().wrap_style, WrapStyle::Balance, "all three Balance");
+    }
 }

docs/ui-parity.md

@@ -96,7 +96,7 @@ interaction feel not yet compared.
 | Shape builder (Shift+M) on fills, strokes and open paths; variable width (Shift+W), one side with Alt | done | |
 | Boolean groups: clicked where the result is, double-click or Cmd/Ctrl-click into operands, live results while dragging or editing points, per-operand operations | done | a group past the path operations' caps (250 000 segments, 2 million possible crossings, 4 million segments swept over a fold) draws without its result, with a warning, and Flatten refuses it (#1104); the Design panel's Boolean groups menu leads Union, Subtract, Intersect and Exclude with their own icons, two offset squares with the result filled at reduced alpha (#2003) |
 | Text: point, auto height, fixed; caret, words, lines, IME | done | Backspace or Delete at the start of a list item takes its marker and keeps its level, the paragraph starting where the item's text did ("delete the counter, but keep the same level of indentation", Create bulleted and numbered lists; `text_tail_tests::list_keys_at_list_items`, text crate `behaviour_tests`); max lines on auto-width text keep it auto width, hugging up to that many lines and growing with its longest line ("Text resizing is set to auto height or auto width", Explore text properties; `text_behaviour_tests::max_lines_on_auto_width_text_keeps_auto_width_and_hugs_that_many_lines`); Alt+Enter while editing opens the link at the caret, web and mail links only (`text.openLink`; "press ⌥Option Return/Alt Enter to activate a focused link", Accessibility at Figma; `text_link_tests`); the font picker previews a family on the canvas while hovered (no undo step; Escape restores, #653) and Up/Down step through it (#352); a selection highlight after a line break starts at that line's start and an empty last line shows its mark (#665); carets step over whole emoji and accented letters; colour emoji draw from their colour tables (#300); IME composition replayed in tests as macOS sends it, not yet checked on a Mac (#747); CJK words by script run (no dictionary); vertical trim in Type settings; no spell check |
-| Text: wrap style (Auto, Balance, Pretty) | done | per text layer (`wrapStyle` on `node.set`, `text.wrapStyle`, the Type settings control under Vertical trim, inspect, CSS `text-wrap: balance` or `pretty`): Auto breaks greedily; Balance narrows each paragraph as far as it goes without another line, so its lines come out close to the same length (what browsers do for `text-wrap: balance`); Pretty keeps lines full and, when the last line is one word, narrows one of the last four lines just enough to give a word to the lines after it (Explore text properties: "Auto: Figma fits as many words as possible on each line before wrapping to the next", "Balance: Figma distributes text as evenly as possible across every line, so each line is close to the same length", "Pretty: Figma keeps each line full, but adjusts the last four lines to avoid an orphan"). Saved line breaks from a file still win. At three levels, as "You can apply a wrap style at three levels: Text layer, Paragraph, Text style" says: the paragraph level is the caret's or the selection's paragraphs while editing (`text.wrapStyle`; the control follows them), or `start`/`end` on `node.set wrapStyle` (a paragraph's own style beats the layer's; setting the layer sets every paragraph again; Enter carries it to the new paragraph; inspect reports `lineWrapStyles` when paragraphs differ and CSS `text-wrap` only when they agree); the text-style level is a style's `wrapStyle` (shown read-only in the style editor, applied with the style, moved by `style.update`, unlinking when edited). The `.fig` import/export mapping stays open (#1827). Test: `text_behaviour_tests::wrap_style_per_paragraph_overrides_the_layers`, `styles_behaviour_tests::text_styles_carry_the_wrap_style`, `text_behaviour_tests::balance_and_pretty_wrap_styles_break_lines_as_documented` |
+| Text: wrap style (Auto, Balance, Pretty) | done | per text layer (`wrapStyle` on `node.set`, `text.wrapStyle`, the Type settings control under Vertical trim, inspect, CSS `text-wrap: balance` or `pretty`): Auto breaks greedily; Balance narrows each paragraph as far as it goes without another line, so its lines come out close to the same length (what browsers do for `text-wrap: balance`); Pretty keeps lines full and, when the last line is one word, narrows one of the last four lines just enough to give a word to the lines after it (Explore text properties: "Auto: Figma fits as many words as possible on each line before wrapping to the next", "Balance: Figma distributes text as evenly as possible across every line, so each line is close to the same length", "Pretty: Figma keeps each line full, but adjusts the last four lines to avoid an orphan"). Saved line breaks from a file still win. At three levels, as "You can apply a wrap style at three levels: Text layer, Paragraph, Text style" says: the paragraph level is the caret's or the selection's paragraphs while editing (`text.wrapStyle`; the control follows them), or `start`/`end` on `node.set wrapStyle` (a paragraph's own style beats the layer's; setting the layer sets every paragraph again; Enter carries it to the new paragraph; inspect reports `lineWrapStyles` when paragraphs differ and CSS `text-wrap` only when they agree); the text-style level is a style's `wrapStyle` (shown read-only in the style editor, applied with the style, moved by `style.update`, unlinking when edited). The `.fig` import/export mapping stays open (#1827): a `.fig` export leaves the wrap styles out and a `.fig` import reads every text as Auto, so the wrap styles are lost through a `.fig` round trip. Test: `text_behaviour_tests::wrap_style_per_paragraph_overrides_the_layers`, `styles_behaviour_tests::text_styles_carry_the_wrap_style`, `text_behaviour_tests::balance_and_pretty_wrap_styles_break_lines_as_documented` |
 | Text: direction override (Text ▸ Text direction) | done | per paragraph (`ParaList::direction`: auto, ltr, rtl): Text ▸ Text direction ▸ Auto / Left to right / Right to left and `text.direction {direction, ids?}` set the edited paragraphs while editing, else every paragraph of the selected texts; `node.set textDirection` the layer's (or the chars `start`/`end` name); the Type settings control appears once a right-to-left script is in the text or a direction is forced; inspect reports `textDirection` when the paragraphs agree and `lineDirections` otherwise; Developer Mode's CSS writes `direction: ltr` or `rtl` when every paragraph is forced the same way (with `text-align: left` beside `rtl`, as Left is absolute on the canvas); `.fig` import and export carry each line's `sourceDirectionality`, read up to the paragraph count. Layout gives the paragraph its base level, so a forced right-to-left paragraph of Latin letters starts at the right, mirrors its list gutter and indent and orders its runs right to left, and a forced left-to-right paragraph of Hebrew the other way ("By default, Figma automatically handles text direction based on language detection. However, controls are available to override text direction per paragraph", "Go to Text > Text direction. Select Left to right or Right to left", Add right-to-left text). Not included: a direction in text styles (the article names none). Tests: `text_behaviour_tests::text_direction_is_forced_per_paragraph`, `fig::text_direction_tests` |
 | Text: superscript and subscript | done | `sups` / `subs` use the font's own glyphs where it has the feature and every letter or digit of the run gets one; otherwise the standard glyphs are drawn shrunk and raised or lowered by the font's OS/2 superscript and subscript metrics (0.65 em at 0.35 em up or 0.14 em down without them), and a run mixing available and unavailable glyphs is synthesised whole, as Explore text properties says ("Figma draws a synthesized version by using the font's standard version of the character, shrinking it, and positioning it accordingly"; mixed glyphs "all update to the synthesized form for consistency"), #1828; tests `text::tests::superscript_native_or_synthesised_and_never_mixed`, `text_behaviour_tests::superscript_and_subscript_are_synthesised_without_glyphs_for_them` |
 | Eyedropper (I) | done | picks the colour seen under the pointer (opaque) into the selection's fill and the recent colours, one undo step (`fx_behaviour_tests`); with Cmd/Ctrl+Shift held it makes a colour style or variable of it instead, as the reference app's eyedropper does: a Create from color window asks which, its name (the next free "Color n") and a variable's collection (the file's first, or a new one made with it in the same undo step), and leaves the selection's fills alone (`eyedropper_create_tests`, `sampled_color_tests`) |