Improve repr for type(none) and type(auto) (#4730)

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

crates/typst/src/foundations/ty.rs

@@ -5,7 +5,9 @@ use ecow::{eco_format, EcoString};
 use once_cell::sync::Lazy;
 
 use crate::diag::StrResult;
-use crate::foundations::{cast, func, Func, NativeFuncData, Repr, Scope, Value};
+use crate::foundations::{
+    cast, func, AutoValue, Func, NativeFuncData, NoneValue, Repr, Scope, Value,
+};
 use crate::utils::Static;
 
 #[rustfmt::skip]
@@ -148,7 +150,14 @@ impl Debug for Type {
 
 impl Repr for Type {
     fn repr(&self) -> EcoString {
-        self.long_name().into()
+        if *self == Type::of::<AutoValue>() {
+            "type(auto)"
+        } else if *self == Type::of::<NoneValue>() {
+            "type(none)"
+        } else {
+            self.long_name()
+        }
+        .into()
     }
 }
 

crates/typst/src/foundations/value.rs

@@ -727,6 +727,9 @@ mod tests {
     fn test_value_debug() {
         // Primitives.
         test(Value::None, "none");
+        test(Value::Auto, "auto");
+        test(Value::None.ty(), "type(none)");
+        test(Value::Auto.ty(), "type(auto)");
         test(false, "false");
         test(12i64, "12");
         test(3.24, "3.24");

tests/suite/foundations/type.typ

@@ -23,3 +23,9 @@
 --- issue-3110-associated-function ---
 // Error: 6-18 type string does not contain field `from-unïcode`
 #str.from-unïcode(97)
+
+--- issue-2747-repr-auto-none ---
+#test(repr(none), "none")
+#test(repr(auto), "auto")
+#test(repr(type(none)), "type(none)")
+#test(repr(type(auto)), "type(auto)")