From 4c0f1173abbdba917d2d25921e575e3981ddc15b Mon Sep 17 00:00:00 2001
From: Laurenz <laurmaedje@gmail.com>
Date: Tue, 17 Sep 2024 11:23:08 +0200
Subject: [PATCH] Improve label repr

---
 crates/typst-syntax/src/lexer.rs      | 11 ++++++-----
 crates/typst-syntax/src/lib.rs        |  2 +-
 crates/typst/src/foundations/cast.rs  |  2 +-
 crates/typst/src/foundations/label.rs |  7 ++++++-
 4 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/crates/typst-syntax/src/lexer.rs b/crates/typst-syntax/src/lexer.rs
index 721225c6e..3bb3f2978 100644
--- a/crates/typst-syntax/src/lexer.rs
+++ b/crates/typst-syntax/src/lexer.rs
@@ -934,13 +934,14 @@ fn is_math_id_continue(c: char) -> bool {
     is_xid_continue(c) && c != '_'
 }
 
+/// Returns true if this string is valid in a label literal.
+#[inline]
+pub fn is_valid_label_literal(string: &str) -> bool {
+    !string.is_empty() && string.chars().all(is_valid_in_label_literal)
+}
+
 /// Whether a character can be part of a label literal's name.
 #[inline]
 fn is_valid_in_label_literal(c: char) -> bool {
     is_id_continue(c) || matches!(c, ':' | '.')
 }
-
-/// Returns true if this string is valid in a label literal.
-pub fn is_valid_label_literal_id(id: &str) -> bool {
-    !id.is_empty() && id.chars().all(is_valid_in_label_literal)
-}
diff --git a/crates/typst-syntax/src/lib.rs b/crates/typst-syntax/src/lib.rs
index 5e7b710fc..055c3d77d 100644
--- a/crates/typst-syntax/src/lib.rs
+++ b/crates/typst-syntax/src/lib.rs
@@ -19,7 +19,7 @@ pub use self::file::FileId;
 pub use self::highlight::{highlight, highlight_html, Tag};
 pub use self::kind::SyntaxKind;
 pub use self::lexer::{
-    is_id_continue, is_id_start, is_ident, is_newline, is_valid_label_literal_id,
+    is_id_continue, is_id_start, is_ident, is_newline, is_valid_label_literal,
     link_prefix, split_newlines,
 };
 pub use self::node::{LinkedChildren, LinkedNode, Side, SyntaxError, SyntaxNode};
diff --git a/crates/typst/src/foundations/cast.rs b/crates/typst/src/foundations/cast.rs
index 51e361289..2659af140 100644
--- a/crates/typst/src/foundations/cast.rs
+++ b/crates/typst/src/foundations/cast.rs
@@ -336,7 +336,7 @@ impl CastInfo {
             }
         } else if let Value::Str(s) = found {
             if !matching_type && parts.iter().any(|p| p == "label") {
-                if typst_syntax::is_valid_label_literal_id(s) {
+                if typst_syntax::is_valid_label_literal(s) {
                     msg.hint(eco_format!(
                         "use `<{s}>` or `label({})` to create a label",
                         s.repr()
diff --git a/crates/typst/src/foundations/label.rs b/crates/typst/src/foundations/label.rs
index 8f15d3178..c510ba1ef 100644
--- a/crates/typst/src/foundations/label.rs
+++ b/crates/typst/src/foundations/label.rs
@@ -1,6 +1,7 @@
 use ecow::{eco_format, EcoString};
 
 use crate::foundations::{func, scope, ty, Repr};
+use crate::syntax::is_valid_label_literal;
 use crate::utils::PicoStr;
 
 /// A label for an element.
@@ -66,7 +67,11 @@ impl Label {
 
 impl Repr for Label {
     fn repr(&self) -> EcoString {
-        eco_format!("<{}>", self.as_str())
+        if is_valid_label_literal(self.as_str()) {
+            eco_format!("<{}>", self.as_str())
+        } else {
+            eco_format!("label({})", self.as_str().repr())
+        }
     }
 }