diff --git a/crates/text/src/layout.rs b/crates/text/src/layout.rs
index 1f2e32115..179478517 100644
--- a/crates/text/src/layout.rs
+++ b/crates/text/src/layout.rs
@@ -1239,372 +1239,4 @@ pub fn measure(text: &str, style: &TextStyle) -> f32 {
 }
 
 #[cfg(test)]
-mod tests {
-    use super::*;
-
-    fn st(size: f32) -> TextStyle {
-        TextStyle { size, ..Default::default() }
-    }
-
-    fn ids(text: &str, s: &TextStyle) -> Vec<u32> {
-        layout_uncached(text, s, &ParagraphStyle::default()).glyphs.iter().map(|g| g.id).collect()
-    }
-
-    fn ot(f: impl FnOnce(&mut OpenType)) -> TextStyle {
-        let mut s = st(100.0);
-        f(&mut s.opentype);
-        s
-    }
-
-    fn serif() -> TextStyle {
-        TextStyle { family: "Noto Serif".into(), ..st(100.0) }
-    }
-
-    #[test]
-    fn bundled_faces_list_their_features() {
-        let inter = fonts::face(fonts::resolve("Inter", "Regular").face).features();
-        for t in ["ss01", "dlig", "frac", "tnum", "sups", "ordn"] {
-            assert!(inter.iter().any(|f| f == t), "{t} in {inter:?}");
-        }
-        let serif = fonts::face(fonts::resolve("Noto Serif", "Regular").face).features();
-        for t in ["smcp", "c2sc", "onum", "lnum"] {
-            assert!(serif.iter().any(|f| f == t), "{t} in {serif:?}");
-        }
-    }
-
-    #[test]
-    fn opentype_features_substitute_glyphs() {
-        let plain = st(100.0);
-        // Stylistic sets, fractions, ordinals, figure widths and discretionary ligatures.
-        assert_ne!(ids("1234567890", &plain), ids("1234567890", &ot(|o| o.set_stylistic_set(1, true))), "ss01 alternate digits");
-        assert_eq!(ids("1234567890", &plain), ids("1234567890", &ot(|o| o.set_stylistic_set(20, true))), "Inter has no ss20");
-        assert_ne!(ids("1/2", &plain), ids("1/2", &ot(|o| o.fractions = true)), "frac");
-        assert_ne!(ids("1a 2o No", &plain), ids("1a 2o No", &ot(|o| o.ordinals = true)), "ordn");
-        let tab = measure("1111", &ot(|o| o.figure_width = effectcraft_keyframe::FigureWidth::Tabular));
-        let prop = measure("1111", &ot(|o| o.figure_width = effectcraft_keyframe::FigureWidth::Proportional));
-        assert!((tab - prop).abs() > 1.0, "tabular {tab} vs proportional {prop}");
-        // Old-style figures (Noto Serif).
-        let old = TextStyle { opentype: OpenType { figure_style: effectcraft_keyframe::FigureStyle::OldStyle, ..Default::default() }, ..serif() };
-        assert_ne!(ids("123", &serif()), ids("123", &old), "onum");
-        // Contextual alternates are on by default; turning them off can only keep or change glyphs.
-        let no_calt = ot(|o| o.contextual_alternates = false);
-        assert_eq!(ids("Hello", &plain).len(), ids("Hello", &no_calt).len());
-    }
-
-    #[test]
-    fn true_small_caps_and_superscripts_with_faux_fallback() {
-        // Noto Serif has smcp: lowercase letters take their own small-capital glyphs at full size.
-        let sc = TextStyle { caps: Caps::Small, ..serif() };
-        let l = layout_uncached("Ab", &sc, &ParagraphStyle::default());
-        let upper_b = ids("B", &serif())[0];
-        assert_ne!(l.glyphs[1].id, upper_b, "true small cap glyph, not a scaled capital");
-        assert_eq!(l.glyphs[1].size, 100.0);
-        // Inter has no smcp: a capital scaled down.
-        let faux = layout_uncached("Ab", &TextStyle { caps: Caps::Small, ..st(100.0) }, &ParagraphStyle::default());
-        assert_eq!(faux.glyphs[1].id, ids("B", &st(100.0))[0]);
-        assert!((faux.glyphs[1].size - 78.0).abs() < 0.01);
-        // All Small Caps: capitals become small capitals too (c2sc).
-        let all = TextStyle { opentype: OpenType { all_small_caps: true, ..Default::default() }, ..serif() };
-        let a = layout_uncached("AB", &all, &ParagraphStyle::default());
-        assert_ne!(a.glyphs[0].id, ids("A", &serif())[0]);
-        // Superscript: Inter's sups figures at full size on the baseline; letters it lacks are
-        // synthesized (smaller and raised).
-        let sup = TextStyle { script: Script::Super, ..st(100.0) };
-        let s2 = layout_uncached("2", &sup, &ParagraphStyle::default());
-        assert_ne!(s2.glyphs[0].id, ids("2", &st(100.0))[0]);
-        assert_eq!(s2.glyphs[0].size, 100.0);
-        assert_eq!(s2.glyphs[0].y, 0.0);
-        let sq = layout_uncached("q", &sup, &ParagraphStyle::default());
-        if !feature_substitutes(sq.glyphs[0].face, b"sups", 'q') {
-            assert!(sq.glyphs[0].size < 60.0 && sq.glyphs[0].y < -20.0, "{:?}", sq.glyphs[0]);
-        }
-        let sub = layout_uncached("2", &TextStyle { script: Script::Sub, ..st(100.0) }, &ParagraphStyle::default());
-        assert_ne!(sub.glyphs[0].id, s2.glyphs[0].id);
-    }
-
-    #[test]
-    fn kerning_and_ligatures_change_advances() {
-        let kern = measure("AVAVAV", &st(100.0));
-        let nokern = measure("AVAVAV", &TextStyle { kerning: false, ..st(100.0) });
-        assert!(kern < nokern - 5.0, "kerning tightens AV: {kern} vs {nokern}");
-        // tracking adds 1/1000 em per cluster
-        let tracked = measure("AVAVAV", &TextStyle { tracking: 100.0, ..st(100.0) });
-        assert!((tracked - kern - 6.0 * 10.0).abs() < 0.5, "{tracked} {kern}");
-    }
-
-    #[test]
-    fn point_text_alignment() {
-        let l = layout("Hello", &st(50.0), &ParagraphStyle { align: Align::Center, ..Default::default() });
-        let line = &l.lines[0];
-        assert!((line.x + line.width / 2.0).abs() < 0.01);
-        let r = layout("Hello", &st(50.0), &ParagraphStyle { align: Align::Right, ..Default::default() });
-        assert!((r.lines[0].x + r.lines[0].width).abs() < 0.01);
-        assert_eq!(l.glyphs.len(), 5);
-        assert!(l.bounds[1] < -30.0 && l.bounds[3] > 5.0, "{:?}", l.bounds);
-    }
-
-    #[test]
-    fn wraps_area_text_and_justifies() {
-        let p = ParagraphStyle { width: Some(300.0), align: Align::Justify, ..Default::default() };
-        let l = layout("the quick brown fox jumps over the lazy dog again and again", &st(40.0), &p);
-        assert!(l.lines.len() >= 3, "{}", l.lines.len());
-        for line in &l.lines[..l.lines.len() - 1] {
-            assert!((line.width - 300.0).abs() < 0.5, "justified to the box: {}", line.width);
-        }
-        // the lines tile the text
-        assert_eq!(l.lines[0].range.start, 0);
-        for w in l.lines.windows(2) {
-            assert_eq!(w[0].range.end, w[1].range.start);
-            assert!(w[1].baseline > w[0].baseline);
-        }
-        let left = layout("the quick brown fox jumps over the lazy dog", &st(40.0), &ParagraphStyle { width: Some(300.0), ..Default::default() });
-        assert!(left.lines.iter().all(|l| l.width <= 300.0 + 0.01));
-    }
-
-    #[test]
-    fn newlines_make_paragraphs_and_leading_adds() {
-        let l = layout("one\ntwo\n\nfour", &st(30.0), &ParagraphStyle::default());
-        assert_eq!(l.lines.len(), 4);
-        assert_eq!(l.lines[1].range, 4..7);
-        assert_eq!(l.lines[2].range, 8..8);
-        let gap = l.lines[1].baseline - l.lines[0].baseline;
-        let l2 = layout("one\ntwo", &st(30.0), &ParagraphStyle { leading: 10.0, ..Default::default() });
-        assert!((l2.lines[1].baseline - l2.lines[0].baseline - gap - 10.0).abs() < 1e-3);
-    }
-
-    #[test]
-    fn carets_and_hit_testing() {
-        let l = layout("abc\nde", &st(40.0), &ParagraphStyle::default());
-        let (x0, _, li0) = l.caret(0);
-        let (x1, _, _) = l.caret(1);
-        let (x3, _, _) = l.caret(3);
-        assert!(x0.abs() < 1e-3 && x1 > x0 && x3 > x1);
-        assert_eq!(li0, 0);
-        let (_, b4, li4) = l.caret(4);
-        assert_eq!(li4, 1);
-        assert!(b4 > 0.0);
-        assert_eq!(l.hit(x1 + 1.0, 0.0), 1);
-        assert_eq!(l.hit(1000.0, b4), 6);
-        let rects = l.selection_rects(1, 5);
-        assert_eq!(rects.len(), 2);
-    }
-
-    #[test]
-    fn bidi_reorders_rtl_runs() {
-        // Hebrew letters are laid out right-to-left: the first logical letter is rightmost.
-        let l = layout("ab \u{5d0}\u{5d1}\u{5d2} cd", &st(40.0), &ParagraphStyle::default());
-        let x_of = |byte: usize| l.glyphs.iter().find(|g| g.cluster == byte).map(|g| g.x).unwrap();
-        let alef = "ab ".len();
-        let gimel = alef + 4;
-        assert!(x_of(alef) > x_of(gimel), "alef right of gimel");
-        assert!(x_of(0) < x_of(gimel) && x_of(alef) < x_of("ab \u{5d0}\u{5d1}\u{5d2} ".len()));
-    }
-
-    #[test]
-    fn caps_and_small_caps() {
-        let s = st(50.0);
-        let up = measure("HELLO", &s);
-        let all = measure("hello", &TextStyle { caps: Caps::All, ..s.clone() });
-        assert!((up - all).abs() < 0.01);
-        let small = measure("hello", &TextStyle { caps: Caps::Small, ..s.clone() });
-        assert!(small < up * 0.9 && small > up * 0.6, "{small} {up}");
-        let l = layout("Hi", &TextStyle { baseline_shift: 10.0, underline: true, ..s }, &ParagraphStyle::default());
-        assert!((l.glyphs[0].y + 10.0).abs() < 1e-3);
-        assert_eq!(l.underlines.len(), 1);
-    }
-
-    #[test]
-    fn ligature_caret_interpolates() {
-        // Inter has an "fi"-like ligature only via calt in some versions; use "ffi" which most
-        // fonts ligate. Whatever shaping does, every char boundary has a caret.
-        let l = layout("office", &st(40.0), &ParagraphStyle::default());
-        let stops: Vec<usize> = l.lines[0].carets.iter().map(|c| c.0).collect();
-        assert_eq!(stops, vec![0, 1, 2, 3, 4, 5, 6]);
-        let xs: Vec<f32> = l.lines[0].carets.iter().map(|c| c.1).collect();
-        assert!(xs.windows(2).all(|w| w[1] >= w[0]), "{xs:?}");
-    }
-
-    #[test]
-    fn fallback_font_for_missing_glyphs() {
-        // Inter lacks Devanagari/Hebrew; Noto Serif lacks Hebrew too → glyphs still produced (notdef)
-        let l = layout("A\u{3b1}", &TextStyle { family: "Noto Serif".into(), ..st(40.0) }, &ParagraphStyle::default());
-        assert_eq!(l.glyphs.len(), 2);
-        assert!(l.glyphs.iter().all(|g| g.id != 0));
-    }
-
-    #[test]
-    fn empty_text_has_a_caret() {
-        let l = layout("", &st(40.0), &ParagraphStyle::default());
-        assert_eq!(l.lines.len(), 1);
-        assert_eq!(l.caret(0).0, 0.0);
-        assert!(l.bounds[3] > l.bounds[1]);
-    }
-
-    fn rich(text: &str, runs: &[(Range<usize>, TextStyle)], para: ParagraphStyle) -> Layout {
-        layout_rich_uncached(text, runs, &[para])
-    }
-
-    #[test]
-    fn mixed_sizes_share_a_baseline_and_take_the_largest_leading() {
-        let text = "small BIG\nnext";
-        let runs = [(0..6, st(20.0)), (6..9, st(80.0)), (9..text.len(), st(20.0))];
-        let l = rich(text, &runs, ParagraphStyle::default());
-        assert_eq!(l.lines.len(), 2);
-        let y0 = l.glyphs[0].y;
-        assert!(l.glyphs[..9].iter().all(|g| (g.y - y0).abs() < 1e-3), "one baseline per line");
-        assert!(l.glyphs[7].size > l.glyphs[0].size * 3.0);
-        // Line 2's advance is its own leading (20 px text: 24 px); line 1 is as tall as the big run.
-        assert!((l.lines[1].baseline - l.lines[0].baseline - 24.0).abs() < 1e-3, "{}", l.lines[1].baseline);
-        assert!(l.lines[0].ascent > 60.0);
-        // A big run on the second line pushes it down by its 120% leading.
-        let text2 = "aa\nBB";
-        let l2 = rich(text2, &[(0..3, st(20.0)), (3..5, st(80.0))], ParagraphStyle::default());
-        assert!((l2.lines[1].baseline - 96.0).abs() < 1e-3);
-        // Explicit leading wins over auto.
-        let mut fixed = st(20.0);
-        fixed.leading = Some(50.0);
-        let l3 = rich("a\nb", &[(0..3, fixed)], ParagraphStyle::default());
-        assert!((l3.lines[1].baseline - 50.0).abs() < 1e-3);
-    }
-
-    #[test]
-    fn super_subscript_tsume_and_kerning_metrics() {
-        let base = st(100.0);
-        let sup = TextStyle { script: Script::Super, ..base.clone() };
-        let sub = TextStyle { script: Script::Sub, ..base.clone() };
-        // A letter the font has no superior / inferior glyph for: synthesized.
-        let inter = fonts::resolve("Inter", "Regular").face;
-        let c = "qwkzvjxyQWK".chars().find(|&c| !feature_substitutes(inter, b"sups", c) && !feature_substitutes(inter, b"subs", c)).unwrap();
-        let text: String = ['x', c, 'y', c].iter().collect();
-        let l = rich(&text, &[(0..1, base.clone()), (1..2, sup), (2..3, base.clone()), (3..4, sub)], ParagraphStyle::default());
-        let g = &l.glyphs;
-        assert!((g[1].size - 58.3).abs() < 0.1);
-        assert!((g[1].y - (g[0].y - 33.3)).abs() < 0.1, "superscript raised by a third of the size");
-        assert!((g[3].y - (g[2].y + 33.3)).abs() < 0.1, "subscript lowered");
-        // Tsume removes side bearings; full tsume is narrower than none.
-        let w0 = measure("onion", &base);
-        let w1 = measure("onion", &TextStyle { tsume: 1.0, ..base.clone() });
-        assert!(w1 < w0 - 5.0, "{w1} vs {w0}");
-        // Manual kerning: +100/1000 em before each of the 5 later characters of AVAVAV, metrics off.
-        let nokern = measure("AVAVAV", &TextStyle { kerning: false, ..base.clone() });
-        let manual = measure("AVAVAV", &TextStyle { manual_kern: Some(100.0), ..base.clone() });
-        assert!((manual - nokern - 50.0).abs() < 0.5, "{manual} {nokern}");
-        let optical = measure("AVAVAV", &TextStyle { optical: true, ..base.clone() });
-        assert!(optical > 0.0 && (optical - nokern).abs() < 100.0);
-        // Horizontal scale stretches advances.
-        let wide = measure("onion", &TextStyle { h_scale: 2.0, ..base.clone() });
-        assert!((wide - 2.0 * w0).abs() < 0.5);
-        let l = layout("o", &TextStyle { h_scale: 2.0, v_scale: 0.5, ..base }, &ParagraphStyle::default());
-        assert_eq!((l.glyphs[0].h_scale, l.glyphs[0].v_scale), (2.0, 0.5));
-    }
-
-    #[test]
-    fn indents_and_paragraph_spacing() {
-        let s = st(20.0);
-        let text = "first paragraph here\nsecond one";
-        let p0 = ParagraphStyle { width: Some(400.0), indent_start: 30.0, indent_first: 15.0, space_after: 10.0, ..Default::default() };
-        let p1 = ParagraphStyle { width: Some(400.0), indent_end: 50.0, align: Align::Right, space_before: 7.0, ..Default::default() };
-        let l = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p0.clone(), p1]);
-        assert!((l.lines[0].x - 45.0).abs() < 1e-3, "left + first-line indent: {}", l.lines[0].x);
-        assert!((l.lines[1].x + l.lines[1].width - 350.0).abs() < 0.5, "right indent: {}", l.lines[1].x + l.lines[1].width);
-        assert!((l.lines[1].baseline - l.lines[0].baseline - (24.0 + 10.0 + 7.0)).abs() < 1e-3);
-        assert_eq!((l.lines[0].para, l.lines[1].para), (0, 1));
-        assert!(l.lines[0].para_end && l.lines[1].para_end);
-        // Wrapped lines after the first don't get the first-line indent.
-        let long = "word ".repeat(30);
-        let l = layout_rich_uncached(&long, &[(0..long.len(), s.clone())], &[p0]);
-        assert!(l.lines.len() > 2);
-        assert!((l.lines[1].x - 30.0).abs() < 1e-3);
-        assert!(l.lines.iter().all(|ln| ln.x + ln.width <= 400.0 + 0.5));
-        assert!(!l.lines[0].para_end);
-        // Point text: a right-aligned paragraph's end indent moves it left of the origin.
-        let l = layout_rich_uncached("abc", &[(0..3, s)], &[ParagraphStyle { align: Align::Right, indent_end: 12.0, ..Default::default() }]);
-        assert!((l.lines[0].x + l.lines[0].width + 12.0).abs() < 1e-3);
-    }
-
-    #[test]
-    fn justify_last_line_modes_and_every_line_composer() {
-        let text = "the quick brown fox jumps over the lazy dog and keeps running far";
-        let s = st(30.0);
-        let p = |last: Align| ParagraphStyle { width: Some(320.0), align: Align::Justify, justify_last: last, ..Default::default() };
-        let left = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p(Align::Left)]);
-        let n = left.lines.len();
-        assert!(n >= 3);
-        assert!((left.lines[0].width - 320.0).abs() < 0.5);
-        assert!(left.lines[n - 1].width < 320.0 && left.lines[n - 1].x.abs() < 1e-3);
-        let center = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p(Align::Center)]);
-        let lc = &center.lines[n - 1];
-        assert!((lc.x - (320.0 - lc.width) / 2.0).abs() < 0.5);
-        let right = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p(Align::Right)]);
-        let lr = &right.lines[n - 1];
-        assert!((lr.x + lr.width - 320.0).abs() < 0.5);
-        let all = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p(Align::Justify)]);
-        assert!((all.lines[n - 1].width - 320.0).abs() < 0.5, "justify all stretches the last line");
-        // Every-line composer: never worse (summed squared slack) than greedy breaking.
-        let slack = |l: &Layout| -> f32 { l.lines[..l.lines.len() - 1].iter().map(|ln| (320.0 - ln.width).powi(2)).sum() };
-        let greedy = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[ParagraphStyle { width: Some(320.0), ..Default::default() }]);
-        let every = layout_rich_uncached(text, &[(0..text.len(), s)], &[ParagraphStyle { width: Some(320.0), every_line: true, ..Default::default() }]);
-        assert!(slack(&every) <= slack(&greedy) + 1e-3, "{} vs {}", slack(&every), slack(&greedy));
-        assert!(every.lines.iter().all(|ln| ln.width <= 320.0 + 0.5));
-    }
-
-    #[test]
-    fn hanging_punctuation_overhangs_the_box() {
-        let s = st(40.0);
-        let text = "\"Hi.\"";
-        let p = ParagraphStyle { width: Some(400.0), hanging: true, ..Default::default() };
-        let l = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p]);
-        assert!(l.lines[0].x < -1.0, "opening quote hangs left: {}", l.lines[0].x);
-        let r = layout_rich_uncached(
-            text,
-            &[(0..text.len(), s)],
-            &[ParagraphStyle { width: Some(400.0), hanging: true, align: Align::Right, ..Default::default() }],
-        );
-        assert!(r.lines[0].x + r.lines[0].width > 401.0, "closing quote hangs right");
-    }
-
-    #[test]
-    fn oversized_layout_requests_are_bounded_without_caching() {
-        let text = "a".repeat(MAX_LAYOUT_BYTES + 1);
-        let layout = layout(&text, &TextStyle::default(), &ParagraphStyle::default());
-        assert_eq!(layout.text_len, text.len());
-        assert!(layout.lines.is_empty() && layout.glyphs.is_empty());
-        assert!(layout_rich_uncached("ok", &[], &[]).lines.len() == 1);
-    }
-
-    #[test]
-    fn rtl_paragraph_carets_run_right_to_left() {
-        let text = "\u{5d0}\u{5d1}\u{5d2}";
-        let l = layout_rich_uncached(text, &[(0..text.len(), st(40.0))], &[ParagraphStyle { rtl: Some(true), ..Default::default() }]);
-        let xs: Vec<f32> = l.lines[0].carets.iter().map(|c| c.1).collect();
-        assert_eq!(xs.len(), 4);
-        assert!(xs.windows(2).all(|w| w[1] < w[0]), "{xs:?}");
-        // Hit testing returns the logical position nearest the point.
-        assert_eq!(l.hit(xs[1] + 0.5, 0.0), 2);
-        assert_eq!(l.hit(xs[0] + 50.0, 0.0), 0);
-    }
-
-    /// #1563: text set in a named instance (`Black`) is laid out at the instance's axis values,
-    /// as if they had been set as variations; axes set on the text itself keep their values.
-    #[test]
-    fn named_instance_sets_the_base_variations() {
-        const FAMILY: &str = "EffectCraft Layout Instance Test";
-        fonts::add_font_data(crate::sfnt::test_font::variable(FAMILY, &[("Light", 300.0, None), ("Black", 900.0, None)], true));
-        let st = |style: &str, variations: Vec<(String, f32)>| TextStyle {
-            family: FAMILY.into(),
-            style: style.into(),
-            size: 50.0,
-            variations,
-            ..Default::default()
-        };
-        let coords = |l: &Layout| l.glyphs.iter().map(|g| crate::variable::coords(g.variations).to_vec()).collect::<Vec<_>>();
-        let black = layout_uncached("Hi", &st("Black", vec![]), &ParagraphStyle::default());
-        assert!(!black.glyphs.is_empty());
-        assert!(coords(&black).iter().all(|c| c == &[("wght".to_string(), 900.0)]), "{:?}", coords(&black));
-        let set = layout_uncached("Hi", &st("Black", vec![("wght".into(), 500.0)]), &ParagraphStyle::default());
-        assert!(coords(&set).iter().all(|c| c == &[("wght".to_string(), 500.0)]), "{:?}", coords(&set));
-        // A static family keeps no variations.
-        let inter = layout_uncached("Hi", &TextStyle::default(), &ParagraphStyle::default());
-        assert!(inter.glyphs.iter().all(|g| g.variations == 0));
-    }
-}
+mod tests;
diff --git a/crates/text/src/layout/tests.rs b/crates/text/src/layout/tests.rs
new file mode 100644
index 000000000..2b0e688ba
--- /dev/null
+++ b/crates/text/src/layout/tests.rs
@@ -0,0 +1,367 @@
+use super::*;
+
+fn st(size: f32) -> TextStyle {
+    TextStyle { size, ..Default::default() }
+}
+
+fn ids(text: &str, s: &TextStyle) -> Vec<u32> {
+    layout_uncached(text, s, &ParagraphStyle::default()).glyphs.iter().map(|g| g.id).collect()
+}
+
+fn ot(f: impl FnOnce(&mut OpenType)) -> TextStyle {
+    let mut s = st(100.0);
+    f(&mut s.opentype);
+    s
+}
+
+fn serif() -> TextStyle {
+    TextStyle { family: "Noto Serif".into(), ..st(100.0) }
+}
+
+#[test]
+fn bundled_faces_list_their_features() {
+    let inter = fonts::face(fonts::resolve("Inter", "Regular").face).features();
+    for t in ["ss01", "dlig", "frac", "tnum", "sups", "ordn"] {
+        assert!(inter.iter().any(|f| f == t), "{t} in {inter:?}");
+    }
+    let serif = fonts::face(fonts::resolve("Noto Serif", "Regular").face).features();
+    for t in ["smcp", "c2sc", "onum", "lnum"] {
+        assert!(serif.iter().any(|f| f == t), "{t} in {serif:?}");
+    }
+}
+
+#[test]
+fn opentype_features_substitute_glyphs() {
+    let plain = st(100.0);
+    // Stylistic sets, fractions, ordinals, figure widths and discretionary ligatures.
+    assert_ne!(ids("1234567890", &plain), ids("1234567890", &ot(|o| o.set_stylistic_set(1, true))), "ss01 alternate digits");
+    assert_eq!(ids("1234567890", &plain), ids("1234567890", &ot(|o| o.set_stylistic_set(20, true))), "Inter has no ss20");
+    assert_ne!(ids("1/2", &plain), ids("1/2", &ot(|o| o.fractions = true)), "frac");
+    assert_ne!(ids("1a 2o No", &plain), ids("1a 2o No", &ot(|o| o.ordinals = true)), "ordn");
+    let tab = measure("1111", &ot(|o| o.figure_width = effectcraft_keyframe::FigureWidth::Tabular));
+    let prop = measure("1111", &ot(|o| o.figure_width = effectcraft_keyframe::FigureWidth::Proportional));
+    assert!((tab - prop).abs() > 1.0, "tabular {tab} vs proportional {prop}");
+    // Old-style figures (Noto Serif).
+    let old = TextStyle { opentype: OpenType { figure_style: effectcraft_keyframe::FigureStyle::OldStyle, ..Default::default() }, ..serif() };
+    assert_ne!(ids("123", &serif()), ids("123", &old), "onum");
+    // Contextual alternates are on by default; turning them off can only keep or change glyphs.
+    let no_calt = ot(|o| o.contextual_alternates = false);
+    assert_eq!(ids("Hello", &plain).len(), ids("Hello", &no_calt).len());
+}
+
+#[test]
+fn true_small_caps_and_superscripts_with_faux_fallback() {
+    // Noto Serif has smcp: lowercase letters take their own small-capital glyphs at full size.
+    let sc = TextStyle { caps: Caps::Small, ..serif() };
+    let l = layout_uncached("Ab", &sc, &ParagraphStyle::default());
+    let upper_b = ids("B", &serif())[0];
+    assert_ne!(l.glyphs[1].id, upper_b, "true small cap glyph, not a scaled capital");
+    assert_eq!(l.glyphs[1].size, 100.0);
+    // Inter has no smcp: a capital scaled down.
+    let faux = layout_uncached("Ab", &TextStyle { caps: Caps::Small, ..st(100.0) }, &ParagraphStyle::default());
+    assert_eq!(faux.glyphs[1].id, ids("B", &st(100.0))[0]);
+    assert!((faux.glyphs[1].size - 78.0).abs() < 0.01);
+    // All Small Caps: capitals become small capitals too (c2sc).
+    let all = TextStyle { opentype: OpenType { all_small_caps: true, ..Default::default() }, ..serif() };
+    let a = layout_uncached("AB", &all, &ParagraphStyle::default());
+    assert_ne!(a.glyphs[0].id, ids("A", &serif())[0]);
+    // Superscript: Inter's sups figures at full size on the baseline; letters it lacks are
+    // synthesized (smaller and raised).
+    let sup = TextStyle { script: Script::Super, ..st(100.0) };
+    let s2 = layout_uncached("2", &sup, &ParagraphStyle::default());
+    assert_ne!(s2.glyphs[0].id, ids("2", &st(100.0))[0]);
+    assert_eq!(s2.glyphs[0].size, 100.0);
+    assert_eq!(s2.glyphs[0].y, 0.0);
+    let sq = layout_uncached("q", &sup, &ParagraphStyle::default());
+    if !feature_substitutes(sq.glyphs[0].face, b"sups", 'q') {
+        assert!(sq.glyphs[0].size < 60.0 && sq.glyphs[0].y < -20.0, "{:?}", sq.glyphs[0]);
+    }
+    let sub = layout_uncached("2", &TextStyle { script: Script::Sub, ..st(100.0) }, &ParagraphStyle::default());
+    assert_ne!(sub.glyphs[0].id, s2.glyphs[0].id);
+}
+
+#[test]
+fn kerning_and_ligatures_change_advances() {
+    let kern = measure("AVAVAV", &st(100.0));
+    let nokern = measure("AVAVAV", &TextStyle { kerning: false, ..st(100.0) });
+    assert!(kern < nokern - 5.0, "kerning tightens AV: {kern} vs {nokern}");
+    // tracking adds 1/1000 em per cluster
+    let tracked = measure("AVAVAV", &TextStyle { tracking: 100.0, ..st(100.0) });
+    assert!((tracked - kern - 6.0 * 10.0).abs() < 0.5, "{tracked} {kern}");
+}
+
+#[test]
+fn point_text_alignment() {
+    let l = layout("Hello", &st(50.0), &ParagraphStyle { align: Align::Center, ..Default::default() });
+    let line = &l.lines[0];
+    assert!((line.x + line.width / 2.0).abs() < 0.01);
+    let r = layout("Hello", &st(50.0), &ParagraphStyle { align: Align::Right, ..Default::default() });
+    assert!((r.lines[0].x + r.lines[0].width).abs() < 0.01);
+    assert_eq!(l.glyphs.len(), 5);
+    assert!(l.bounds[1] < -30.0 && l.bounds[3] > 5.0, "{:?}", l.bounds);
+}
+
+#[test]
+fn wraps_area_text_and_justifies() {
+    let p = ParagraphStyle { width: Some(300.0), align: Align::Justify, ..Default::default() };
+    let l = layout("the quick brown fox jumps over the lazy dog again and again", &st(40.0), &p);
+    assert!(l.lines.len() >= 3, "{}", l.lines.len());
+    for line in &l.lines[..l.lines.len() - 1] {
+        assert!((line.width - 300.0).abs() < 0.5, "justified to the box: {}", line.width);
+    }
+    // the lines tile the text
+    assert_eq!(l.lines[0].range.start, 0);
+    for w in l.lines.windows(2) {
+        assert_eq!(w[0].range.end, w[1].range.start);
+        assert!(w[1].baseline > w[0].baseline);
+    }
+    let left = layout("the quick brown fox jumps over the lazy dog", &st(40.0), &ParagraphStyle { width: Some(300.0), ..Default::default() });
+    assert!(left.lines.iter().all(|l| l.width <= 300.0 + 0.01));
+}
+
+#[test]
+fn newlines_make_paragraphs_and_leading_adds() {
+    let l = layout("one\ntwo\n\nfour", &st(30.0), &ParagraphStyle::default());
+    assert_eq!(l.lines.len(), 4);
+    assert_eq!(l.lines[1].range, 4..7);
+    assert_eq!(l.lines[2].range, 8..8);
+    let gap = l.lines[1].baseline - l.lines[0].baseline;
+    let l2 = layout("one\ntwo", &st(30.0), &ParagraphStyle { leading: 10.0, ..Default::default() });
+    assert!((l2.lines[1].baseline - l2.lines[0].baseline - gap - 10.0).abs() < 1e-3);
+}
+
+#[test]
+fn carets_and_hit_testing() {
+    let l = layout("abc\nde", &st(40.0), &ParagraphStyle::default());
+    let (x0, _, li0) = l.caret(0);
+    let (x1, _, _) = l.caret(1);
+    let (x3, _, _) = l.caret(3);
+    assert!(x0.abs() < 1e-3 && x1 > x0 && x3 > x1);
+    assert_eq!(li0, 0);
+    let (_, b4, li4) = l.caret(4);
+    assert_eq!(li4, 1);
+    assert!(b4 > 0.0);
+    assert_eq!(l.hit(x1 + 1.0, 0.0), 1);
+    assert_eq!(l.hit(1000.0, b4), 6);
+    let rects = l.selection_rects(1, 5);
+    assert_eq!(rects.len(), 2);
+}
+
+#[test]
+fn bidi_reorders_rtl_runs() {
+    // Hebrew letters are laid out right-to-left: the first logical letter is rightmost.
+    let l = layout("ab \u{5d0}\u{5d1}\u{5d2} cd", &st(40.0), &ParagraphStyle::default());
+    let x_of = |byte: usize| l.glyphs.iter().find(|g| g.cluster == byte).map(|g| g.x).unwrap();
+    let alef = "ab ".len();
+    let gimel = alef + 4;
+    assert!(x_of(alef) > x_of(gimel), "alef right of gimel");
+    assert!(x_of(0) < x_of(gimel) && x_of(alef) < x_of("ab \u{5d0}\u{5d1}\u{5d2} ".len()));
+}
+
+#[test]
+fn caps_and_small_caps() {
+    let s = st(50.0);
+    let up = measure("HELLO", &s);
+    let all = measure("hello", &TextStyle { caps: Caps::All, ..s.clone() });
+    assert!((up - all).abs() < 0.01);
+    let small = measure("hello", &TextStyle { caps: Caps::Small, ..s.clone() });
+    assert!(small < up * 0.9 && small > up * 0.6, "{small} {up}");
+    let l = layout("Hi", &TextStyle { baseline_shift: 10.0, underline: true, ..s }, &ParagraphStyle::default());
+    assert!((l.glyphs[0].y + 10.0).abs() < 1e-3);
+    assert_eq!(l.underlines.len(), 1);
+}
+
+#[test]
+fn ligature_caret_interpolates() {
+    // Inter has an "fi"-like ligature only via calt in some versions; use "ffi" which most
+    // fonts ligate. Whatever shaping does, every char boundary has a caret.
+    let l = layout("office", &st(40.0), &ParagraphStyle::default());
+    let stops: Vec<usize> = l.lines[0].carets.iter().map(|c| c.0).collect();
+    assert_eq!(stops, vec![0, 1, 2, 3, 4, 5, 6]);
+    let xs: Vec<f32> = l.lines[0].carets.iter().map(|c| c.1).collect();
+    assert!(xs.windows(2).all(|w| w[1] >= w[0]), "{xs:?}");
+}
+
+#[test]
+fn fallback_font_for_missing_glyphs() {
+    // Inter lacks Devanagari/Hebrew; Noto Serif lacks Hebrew too → glyphs still produced (notdef)
+    let l = layout("A\u{3b1}", &TextStyle { family: "Noto Serif".into(), ..st(40.0) }, &ParagraphStyle::default());
+    assert_eq!(l.glyphs.len(), 2);
+    assert!(l.glyphs.iter().all(|g| g.id != 0));
+}
+
+#[test]
+fn empty_text_has_a_caret() {
+    let l = layout("", &st(40.0), &ParagraphStyle::default());
+    assert_eq!(l.lines.len(), 1);
+    assert_eq!(l.caret(0).0, 0.0);
+    assert!(l.bounds[3] > l.bounds[1]);
+}
+
+fn rich(text: &str, runs: &[(Range<usize>, TextStyle)], para: ParagraphStyle) -> Layout {
+    layout_rich_uncached(text, runs, &[para])
+}
+
+#[test]
+fn mixed_sizes_share_a_baseline_and_take_the_largest_leading() {
+    let text = "small BIG\nnext";
+    let runs = [(0..6, st(20.0)), (6..9, st(80.0)), (9..text.len(), st(20.0))];
+    let l = rich(text, &runs, ParagraphStyle::default());
+    assert_eq!(l.lines.len(), 2);
+    let y0 = l.glyphs[0].y;
+    assert!(l.glyphs[..9].iter().all(|g| (g.y - y0).abs() < 1e-3), "one baseline per line");
+    assert!(l.glyphs[7].size > l.glyphs[0].size * 3.0);
+    // Line 2's advance is its own leading (20 px text: 24 px); line 1 is as tall as the big run.
+    assert!((l.lines[1].baseline - l.lines[0].baseline - 24.0).abs() < 1e-3, "{}", l.lines[1].baseline);
+    assert!(l.lines[0].ascent > 60.0);
+    // A big run on the second line pushes it down by its 120% leading.
+    let text2 = "aa\nBB";
+    let l2 = rich(text2, &[(0..3, st(20.0)), (3..5, st(80.0))], ParagraphStyle::default());
+    assert!((l2.lines[1].baseline - 96.0).abs() < 1e-3);
+    // Explicit leading wins over auto.
+    let mut fixed = st(20.0);
+    fixed.leading = Some(50.0);
+    let l3 = rich("a\nb", &[(0..3, fixed)], ParagraphStyle::default());
+    assert!((l3.lines[1].baseline - 50.0).abs() < 1e-3);
+}
+
+#[test]
+fn super_subscript_tsume_and_kerning_metrics() {
+    let base = st(100.0);
+    let sup = TextStyle { script: Script::Super, ..base.clone() };
+    let sub = TextStyle { script: Script::Sub, ..base.clone() };
+    // A letter the font has no superior / inferior glyph for: synthesized.
+    let inter = fonts::resolve("Inter", "Regular").face;
+    let c = "qwkzvjxyQWK".chars().find(|&c| !feature_substitutes(inter, b"sups", c) && !feature_substitutes(inter, b"subs", c)).unwrap();
+    let text: String = ['x', c, 'y', c].iter().collect();
+    let l = rich(&text, &[(0..1, base.clone()), (1..2, sup), (2..3, base.clone()), (3..4, sub)], ParagraphStyle::default());
+    let g = &l.glyphs;
+    assert!((g[1].size - 58.3).abs() < 0.1);
+    assert!((g[1].y - (g[0].y - 33.3)).abs() < 0.1, "superscript raised by a third of the size");
+    assert!((g[3].y - (g[2].y + 33.3)).abs() < 0.1, "subscript lowered");
+    // Tsume removes side bearings; full tsume is narrower than none.
+    let w0 = measure("onion", &base);
+    let w1 = measure("onion", &TextStyle { tsume: 1.0, ..base.clone() });
+    assert!(w1 < w0 - 5.0, "{w1} vs {w0}");
+    // Manual kerning: +100/1000 em before each of the 5 later characters of AVAVAV, metrics off.
+    let nokern = measure("AVAVAV", &TextStyle { kerning: false, ..base.clone() });
+    let manual = measure("AVAVAV", &TextStyle { manual_kern: Some(100.0), ..base.clone() });
+    assert!((manual - nokern - 50.0).abs() < 0.5, "{manual} {nokern}");
+    let optical = measure("AVAVAV", &TextStyle { optical: true, ..base.clone() });
+    assert!(optical > 0.0 && (optical - nokern).abs() < 100.0);
+    // Horizontal scale stretches advances.
+    let wide = measure("onion", &TextStyle { h_scale: 2.0, ..base.clone() });
+    assert!((wide - 2.0 * w0).abs() < 0.5);
+    let l = layout("o", &TextStyle { h_scale: 2.0, v_scale: 0.5, ..base }, &ParagraphStyle::default());
+    assert_eq!((l.glyphs[0].h_scale, l.glyphs[0].v_scale), (2.0, 0.5));
+}
+
+#[test]
+fn indents_and_paragraph_spacing() {
+    let s = st(20.0);
+    let text = "first paragraph here\nsecond one";
+    let p0 = ParagraphStyle { width: Some(400.0), indent_start: 30.0, indent_first: 15.0, space_after: 10.0, ..Default::default() };
+    let p1 = ParagraphStyle { width: Some(400.0), indent_end: 50.0, align: Align::Right, space_before: 7.0, ..Default::default() };
+    let l = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p0.clone(), p1]);
+    assert!((l.lines[0].x - 45.0).abs() < 1e-3, "left + first-line indent: {}", l.lines[0].x);
+    assert!((l.lines[1].x + l.lines[1].width - 350.0).abs() < 0.5, "right indent: {}", l.lines[1].x + l.lines[1].width);
+    assert!((l.lines[1].baseline - l.lines[0].baseline - (24.0 + 10.0 + 7.0)).abs() < 1e-3);
+    assert_eq!((l.lines[0].para, l.lines[1].para), (0, 1));
+    assert!(l.lines[0].para_end && l.lines[1].para_end);
+    // Wrapped lines after the first don't get the first-line indent.
+    let long = "word ".repeat(30);
+    let l = layout_rich_uncached(&long, &[(0..long.len(), s.clone())], &[p0]);
+    assert!(l.lines.len() > 2);
+    assert!((l.lines[1].x - 30.0).abs() < 1e-3);
+    assert!(l.lines.iter().all(|ln| ln.x + ln.width <= 400.0 + 0.5));
+    assert!(!l.lines[0].para_end);
+    // Point text: a right-aligned paragraph's end indent moves it left of the origin.
+    let l = layout_rich_uncached("abc", &[(0..3, s)], &[ParagraphStyle { align: Align::Right, indent_end: 12.0, ..Default::default() }]);
+    assert!((l.lines[0].x + l.lines[0].width + 12.0).abs() < 1e-3);
+}
+
+#[test]
+fn justify_last_line_modes_and_every_line_composer() {
+    let text = "the quick brown fox jumps over the lazy dog and keeps running far";
+    let s = st(30.0);
+    let p = |last: Align| ParagraphStyle { width: Some(320.0), align: Align::Justify, justify_last: last, ..Default::default() };
+    let left = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p(Align::Left)]);
+    let n = left.lines.len();
+    assert!(n >= 3);
+    assert!((left.lines[0].width - 320.0).abs() < 0.5);
+    assert!(left.lines[n - 1].width < 320.0 && left.lines[n - 1].x.abs() < 1e-3);
+    let center = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p(Align::Center)]);
+    let lc = &center.lines[n - 1];
+    assert!((lc.x - (320.0 - lc.width) / 2.0).abs() < 0.5);
+    let right = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p(Align::Right)]);
+    let lr = &right.lines[n - 1];
+    assert!((lr.x + lr.width - 320.0).abs() < 0.5);
+    let all = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p(Align::Justify)]);
+    assert!((all.lines[n - 1].width - 320.0).abs() < 0.5, "justify all stretches the last line");
+    // Every-line composer: never worse (summed squared slack) than greedy breaking.
+    let slack = |l: &Layout| -> f32 { l.lines[..l.lines.len() - 1].iter().map(|ln| (320.0 - ln.width).powi(2)).sum() };
+    let greedy = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[ParagraphStyle { width: Some(320.0), ..Default::default() }]);
+    let every = layout_rich_uncached(text, &[(0..text.len(), s)], &[ParagraphStyle { width: Some(320.0), every_line: true, ..Default::default() }]);
+    assert!(slack(&every) <= slack(&greedy) + 1e-3, "{} vs {}", slack(&every), slack(&greedy));
+    assert!(every.lines.iter().all(|ln| ln.width <= 320.0 + 0.5));
+}
+
+#[test]
+fn hanging_punctuation_overhangs_the_box() {
+    let s = st(40.0);
+    let text = "\"Hi.\"";
+    let p = ParagraphStyle { width: Some(400.0), hanging: true, ..Default::default() };
+    let l = layout_rich_uncached(text, &[(0..text.len(), s.clone())], &[p]);
+    assert!(l.lines[0].x < -1.0, "opening quote hangs left: {}", l.lines[0].x);
+    let r = layout_rich_uncached(
+        text,
+        &[(0..text.len(), s)],
+        &[ParagraphStyle { width: Some(400.0), hanging: true, align: Align::Right, ..Default::default() }],
+    );
+    assert!(r.lines[0].x + r.lines[0].width > 401.0, "closing quote hangs right");
+}
+
+#[test]
+fn oversized_layout_requests_are_bounded_without_caching() {
+    let text = "a".repeat(MAX_LAYOUT_BYTES + 1);
+    let layout = layout(&text, &TextStyle::default(), &ParagraphStyle::default());
+    assert_eq!(layout.text_len, text.len());
+    assert!(layout.lines.is_empty() && layout.glyphs.is_empty());
+    assert!(layout_rich_uncached("ok", &[], &[]).lines.len() == 1);
+}
+
+#[test]
+fn rtl_paragraph_carets_run_right_to_left() {
+    let text = "\u{5d0}\u{5d1}\u{5d2}";
+    let l = layout_rich_uncached(text, &[(0..text.len(), st(40.0))], &[ParagraphStyle { rtl: Some(true), ..Default::default() }]);
+    let xs: Vec<f32> = l.lines[0].carets.iter().map(|c| c.1).collect();
+    assert_eq!(xs.len(), 4);
+    assert!(xs.windows(2).all(|w| w[1] < w[0]), "{xs:?}");
+    // Hit testing returns the logical position nearest the point.
+    assert_eq!(l.hit(xs[1] + 0.5, 0.0), 2);
+    assert_eq!(l.hit(xs[0] + 50.0, 0.0), 0);
+}
+
+/// #1563: text set in a named instance (`Black`) is laid out at the instance's axis values,
+/// as if they had been set as variations; axes set on the text itself keep their values.
+#[test]
+fn named_instance_sets_the_base_variations() {
+    const FAMILY: &str = "EffectCraft Layout Instance Test";
+    fonts::add_font_data(crate::sfnt::test_font::variable(FAMILY, &[("Light", 300.0, None), ("Black", 900.0, None)], true));
+    let st = |style: &str, variations: Vec<(String, f32)>| TextStyle {
+        family: FAMILY.into(),
+        style: style.into(),
+        size: 50.0,
+        variations,
+        ..Default::default()
+    };
+    let coords = |l: &Layout| l.glyphs.iter().map(|g| crate::variable::coords(g.variations).to_vec()).collect::<Vec<_>>();
+    let black = layout_uncached("Hi", &st("Black", vec![]), &ParagraphStyle::default());
+    assert!(!black.glyphs.is_empty());
+    assert!(coords(&black).iter().all(|c| c == &[("wght".to_string(), 900.0)]), "{:?}", coords(&black));
+    let set = layout_uncached("Hi", &st("Black", vec![("wght".into(), 500.0)]), &ParagraphStyle::default());
+    assert!(coords(&set).iter().all(|c| c == &[("wght".to_string(), 500.0)]), "{:?}", coords(&set));
+    // A static family keeps no variations.
+    let inter = layout_uncached("Hi", &TextStyle::default(), &ParagraphStyle::default());
+    assert!(inter.glyphs.iter().all(|g| g.variations == 0));
+}