Wrap outline entry body in LRE/RLE + make smart quotes ignore directional control characters (#4491)

Co-authored-by: Laurenz <laurmaedje@gmail.com>

6 files changed, 27 insertions, 8 deletions

diff --git a/crates/typst/src/layout/inline/collect.rs b/crates/typst/src/layout/inline/collect.rs
index f1607460..b6a847f5 100644
--- a/crates/typst/src/layout/inline/collect.rs
+++ b/crates/typst/src/layout/inline/collect.rs
@@ -201,7 +201,7 @@ pub fn collect<'a>(
                 );
                 let peeked = iter.peek().and_then(|(child, _)| {
                     if let Some(elem) = child.to_packed::<TextElem>() {
-                        elem.text().chars().next()
+                        elem.text().chars().find(|c| !is_default_ignorable(*c))
                     } else if child.is::<SmartQuoteElem>() {
                         Some('"')
                     } else if child.is::<SpaceElem>()
@@ -302,7 +302,7 @@ impl<'a> Collector<'a> {
     }
 
     fn push_segment(&mut self, segment: Segment<'a>, is_quote: bool) {
-        if let Some(last) = self.full.chars().last() {
+        if let Some(last) = self.full.chars().rev().find(|c| !is_default_ignorable(*c)) {
             self.quoter.last(last, is_quote);
         }
 
diff --git a/crates/typst/src/layout/inline/linebreak.rs b/crates/typst/src/layout/inline/linebreak.rs
index 9deaa92a..075d24b3 100644
--- a/crates/typst/src/layout/inline/linebreak.rs
+++ b/crates/typst/src/layout/inline/linebreak.rs
@@ -953,3 +953,8 @@ where
         }
     }
 }
+
+/// Whether a codepoint is Unicode `Default_Ignorable`.
+pub fn is_default_ignorable(c: char) -> bool {
+    DEFAULT_IGNORABLE_DATA.as_borrowed().contains(c)
+}
diff --git a/crates/typst/src/layout/inline/mod.rs b/crates/typst/src/layout/inline/mod.rs
index f89de169..821b4f57 100644
--- a/crates/typst/src/layout/inline/mod.rs
+++ b/crates/typst/src/layout/inline/mod.rs
@@ -10,7 +10,7 @@ use comemo::{Track, Tracked, TrackedMut};
 use self::collect::{collect, Item, Segment, SpanMapper};
 use self::finalize::finalize;
 use self::line::{commit, line, Line};
-use self::linebreak::{linebreak, Breakpoint};
+use self::linebreak::{is_default_ignorable, linebreak, Breakpoint};
 use self::prepare::{prepare, Preparation};
 use self::shaping::{
     cjk_punct_style, is_of_cj_script, shape_range, ShapedGlyph, ShapedText,
diff --git a/crates/typst/src/model/outline.rs b/crates/typst/src/model/outline.rs
index 09047285..ec1e5f1b 100644
--- a/crates/typst/src/model/outline.rs
+++ b/crates/typst/src/model/outline.rs
@@ -483,7 +483,7 @@ impl OutlineEntry {
 
 impl Show for Packed<OutlineEntry> {
     #[typst_macros::time(name = "outline.entry", span = self.span())]
-    fn show(&self, _: &mut Engine, _: StyleChain) -> SourceResult<Content> {
+    fn show(&self, _: &mut Engine, styles: StyleChain) -> SourceResult<Content> {
         let mut seq = vec![];
         let elem = self.element();
 
@@ -500,7 +500,11 @@ impl Show for Packed<OutlineEntry> {
         };
 
         // The body text remains overridable.
-        seq.push(self.body().clone().linked(Destination::Location(location)));
+        crate::text::isolate(
+            self.body().clone().linked(Destination::Location(location)),
+            styles,
+            &mut seq,
+        );
 
         // Add filler symbols between the section name and page number.
         if let Some(filler) = self.fill() {
diff --git a/crates/typst/src/text/mod.rs b/crates/typst/src/text/mod.rs
index 7648f08f..d42e4df8 100644
--- a/crates/typst/src/text/mod.rs
+++ b/crates/typst/src/text/mod.rs
@@ -1299,3 +1299,13 @@ cast! {
         ret
     },
 }
+
+/// Pushes `text` wrapped in LRE/RLE + PDF to `out`.
+pub(crate) fn isolate(text: Content, styles: StyleChain, out: &mut Vec<Content>) {
+    out.push(TextElem::packed(match TextElem::dir_in(styles) {
+        Dir::RTL => "\u{202B}",
+        _ => "\u{202A}",
+    }));
+    out.push(text);
+    out.push(TextElem::packed("\u{202C}"));
+}
diff --git a/crates/typst/src/text/smartquote.rs b/crates/typst/src/text/smartquote.rs
index 236d0636..797f0804 100644
--- a/crates/typst/src/text/smartquote.rs
+++ b/crates/typst/src/text/smartquote.rs
@@ -123,7 +123,7 @@ impl SmartQuoter {
 
     /// Process the last seen character.
     pub fn last(&mut self, c: char, is_quote: bool) {
-        self.expect_opening = is_ignorable(c) || is_opening_bracket(c);
+        self.expect_opening = is_exterior_to_quote(c) || is_opening_bracket(c);
         self.last_num = c.is_numeric();
         if !is_quote {
             self.prev_quote_type = None;
@@ -150,7 +150,7 @@ impl SmartQuoter {
             self.prev_quote_type = Some(double);
             quotes.open(double)
         } else if self.quote_depth > 0
-            && (peeked.is_ascii_punctuation() || is_ignorable(peeked))
+            && (peeked.is_ascii_punctuation() || is_exterior_to_quote(peeked))
         {
             self.quote_depth -= 1;
             quotes.close(double)
@@ -168,7 +168,7 @@ impl Default for SmartQuoter {
     }
 }
 
-fn is_ignorable(c: char) -> bool {
+fn is_exterior_to_quote(c: char) -> bool {
     c.is_whitespace() || is_newline(c)
 }