From 44fe2b6ddc784ad3e705cd8487f753c565c69d19 Mon Sep 17 00:00:00 2001
From: ldm0 <ldm2993593805@163.com>
Date: Sun, 18 Oct 2026 03:37:42 +0800
Subject: [PATCH] fix(layout): honor intrinsic minima in grid tracks and rows

Pin the separate Taffy71617899 and4a618c7b fixes: resolve authored intrinsic item minima for auto-track contributions and before fixing the width used to measure row height. A smaller preferred width must not hide the minimum in either path.

MOL-465: browser regression covers min-content/max-content with auto,0px and50px preferred widths, track positions and row heights. The two pre-fix failures were next-column x40 instead of60 and row height60 instead of20. The Webfont grid nontermination control still completes.

cargo fmt --all; cargo clippy --workspace --all-targets --all-features -- -D warnings; cargo nextest run --no-fail-fast:20277 passed,18 skipped. Initial partial-fix failure logs retained.

Original-commit: 3b602b42404fbaec9789944bb7031142ea88ca77
---
 Cargo.lock                                 |  2 +-
 Cargo.toml                                 |  2 +-
 moli/tests/fetch_cli/layout_regressions.rs | 70 ++++++++++++++++++++++
 3 files changed, 72 insertions(+), 2 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index c21543ab45..8a11fa9d2d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5550,7 +5550,7 @@ dependencies = [
 [[package]]
 name = "taffy"
 version = "0.13.0"
-source = "git+https://github.com/ldm0/taffy?rev=5453d6cdda8d2dd12b87e5237686e0adaf7cc0bc#5453d6cdda8d2dd12b87e5237686e0adaf7cc0bc"
+source = "git+https://github.com/ldm0/taffy?rev=4a618c7b6b7f9c3fbd8b8b0eaf9918ebd2cf9969#4a618c7b6b7f9c3fbd8b8b0eaf9918ebd2cf9969"
 dependencies = [
  "arrayvec",
  "serde",
diff --git a/Cargo.toml b/Cargo.toml
index 51143ee7e7..98836bdfaa 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -117,7 +117,7 @@ stylo_dom = { git = "https://github.com/lexmount/stylo", rev = "0c7e8baf63b6714e
 stylo_static_prefs = { git = "https://github.com/lexmount/stylo", rev = "0c7e8baf63b6714e7614834fadbc09710f3c3d27" }
 stylo_traits = { git = "https://github.com/lexmount/stylo", rev = "0c7e8baf63b6714e7614834fadbc09710f3c3d27" }
 svgtypes = { git = "https://github.com/lexmount/svgtypes", branch = "moli" }
-taffy = { git = "https://github.com/ldm0/taffy", rev = "5453d6cdda8d2dd12b87e5237686e0adaf7cc0bc" }
+taffy = { git = "https://github.com/ldm0/taffy", rev = "4a618c7b6b7f9c3fbd8b8b0eaf9918ebd2cf9969" }
 
 [workspace.lints.clippy]
 disallowed_methods = "deny"
diff --git a/moli/tests/fetch_cli/layout_regressions.rs b/moli/tests/fetch_cli/layout_regressions.rs
index c61a942b93..16088d49e6 100644
--- a/moli/tests/fetch_cli/layout_regressions.rs
+++ b/moli/tests/fetch_cli/layout_regressions.rs
@@ -66,3 +66,73 @@ fn fractional_grid_track_limits_terminate_with_a_finite_item_width() -> Result<(
     assert!((width - 202.44017).abs() < 0.05, "{width}");
     Ok(())
 }
+
+fn probe_font_document(body: &str) -> String {
+    let font = STANDARD.encode(include_bytes!(concat!(
+        env!("CARGO_MANIFEST_DIR"),
+        "/../moli-layout/tests/fixtures/moli-ahem.woff2"
+    )));
+    format!(
+        "<!doctype html><style>@font-face{{font-family:Probe;src:url(data:font/woff2;base64,{font})}}body{{margin:0;font:20px/20px Probe}}</style>{body}"
+    )
+}
+
+const GEOMETRY: &str = r#"(async () => {
+    await document.fonts.ready;
+    return Object.fromEntries([...document.querySelectorAll('[id]')].map(element => {
+        const rect = element.getBoundingClientRect();
+        return [element.id, {x: rect.x, width: rect.width, height: rect.height}];
+    }));
+})()"#;
+
+fn assert_dimension(value: &Value, id: &str, dimension: &str, expected: f64) {
+    let actual = value[id][dimension]
+        .as_f64()
+        .expect("dimension must be numeric");
+    assert!(
+        (actual - expected).abs() < 0.05,
+        "{id}.{dimension}: {actual} != {expected}"
+    );
+}
+
+#[test]
+fn auto_grid_tracks_honor_intrinsic_item_minima_before_measuring_row_height() -> Result<()> {
+    let mut body = String::new();
+    for keyword in ["min-content", "max-content"] {
+        for width in ["auto", "0px", "50px"] {
+            let key = format!("{keyword}-{width}");
+            let grid_width = if keyword == "min-content" { 140 } else { 200 };
+            body.push_str(&format!(
+                "<section><div id='grid-{key}' style='display:grid;grid-template-columns:auto 100px;width:{grid_width}px'><div id='item-{key}' style='min-width:{keyword};width:{width}'>aaaa bbbbb ccc</div><div id='next-{key}'></div></div></section>"
+            ));
+        }
+    }
+    let value = run_layout(&probe_font_document(&body), GEOMETRY, true)?;
+    for keyword in ["min-content", "max-content"] {
+        for width in ["auto", "0px", "50px"] {
+            let key = format!("{keyword}-{width}");
+            let maximum = keyword == "max-content";
+            let item_width = if maximum { 168.0 } else { 60.0 };
+            assert_dimension(&value, &format!("item-{key}"), "width", item_width);
+            assert_dimension(
+                &value,
+                &format!("item-{key}"),
+                "height",
+                if maximum { 20.0 } else { 60.0 },
+            );
+            assert_dimension(
+                &value,
+                &format!("grid-{key}"),
+                "height",
+                if maximum { 20.0 } else { 60.0 },
+            );
+            assert_dimension(
+                &value,
+                &format!("next-{key}"),
+                "x",
+                if maximum { 168.0 } else { 60.0 },
+            );
+        }
+    }
+    Ok(())
+}