From aef36f39627fdc7151aed0fb7ea110dfbf9cabc2 Mon Sep 17 00:00:00 2001
From: Laurenz <laurmaedje@gmail.com>
Date: Fri, 22 Aug 2025 15:04:12 +0200
Subject: [PATCH] Do not consider default ignorables when picking last resort
 font (#6805)

---
 crates/typst-library/src/text/font/book.rs    |  12 +++++++++---
 ...5276-shaping-consecutive-ltr-with-lang.png | Bin 0 -> 179 bytes
 tests/ref/issue-5490-bidi-invalid-range-2.png | Bin 1496 -> 1596 bytes
 tests/suite/layout/inline/bidi.typ            |   4 ++++
 4 files changed, 13 insertions(+), 3 deletions(-)
 create mode 100644 tests/ref/issue-5276-shaping-consecutive-ltr-with-lang.png

diff --git a/crates/typst-library/src/text/font/book.rs b/crates/typst-library/src/text/font/book.rs
index db100d4f7..c9b8f3065 100644
--- a/crates/typst-library/src/text/font/book.rs
+++ b/crates/typst-library/src/text/font/book.rs
@@ -7,7 +7,9 @@ use ttf_parser::{PlatformId, Tag, name_id};
 use unicode_segmentation::UnicodeSegmentation;
 
 use super::exceptions::find_exception;
-use crate::text::{Font, FontStretch, FontStyle, FontVariant, FontWeight};
+use crate::text::{
+    Font, FontStretch, FontStyle, FontVariant, FontWeight, is_default_ignorable,
+};
 
 /// Metadata about a collection of fonts.
 #[derive(Debug, Default, Clone, Hash)]
@@ -99,8 +101,12 @@ impl FontBook {
         variant: FontVariant,
         text: &str,
     ) -> Option<usize> {
-        // Find the fonts that contain the text's first non-space char ...
-        let c = text.chars().find(|c| !c.is_whitespace())?;
+        // Find the fonts that contain the text's first non-space and
+        // non-ignorable char ...
+        let c = text
+            .chars()
+            .find(|&c| !c.is_whitespace() && !is_default_ignorable(c))?;
+
         let ids = self
             .infos
             .iter()
diff --git a/tests/ref/issue-5276-shaping-consecutive-ltr-with-lang.png b/tests/ref/issue-5276-shaping-consecutive-ltr-with-lang.png
new file mode 100644
index 0000000000000000000000000000000000000000..2d7ddb361e4509ee16b41d38cacae3ac67548e15
GIT binary patch
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literal 0
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diff --git a/tests/ref/issue-5490-bidi-invalid-range-2.png b/tests/ref/issue-5490-bidi-invalid-range-2.png
index f93b6309b9357530a7d54a360dae4b2743bd9b1b..58f2c40ce8402724912a8d226097a260bfc76073 100644
GIT binary patch
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diff --git a/tests/suite/layout/inline/bidi.typ b/tests/suite/layout/inline/bidi.typ
index d7601fa1d..103ab6030 100644
--- a/tests/suite/layout/inline/bidi.typ
+++ b/tests/suite/layout/inline/bidi.typ
@@ -92,3 +92,7 @@ Lריווח #h(1cm) R
     #text(lang: "ar")[سلام]
   ],
 )
+
+--- issue-5276-shaping-consecutive-ltr-with-lang ---
+#let a = text(lang: "ar")[\u{645}]
+#a#a