Fix text show-set regression (#3410)

crates/typst/src/realize/process.rs

@@ -129,7 +129,11 @@ fn verdict<'a>(
             continue;
         }
 
-        if let Transformation::Style(transform) = &recipe.transform {
+        // Special handling for show-set rules. Exception: Regex show rules,
+        // those need to be handled like normal transformations.
+        if let (Transformation::Style(transform), false) =
+            (&recipe.transform, matches!(&recipe.selector, Some(Selector::Regex(_))))
+        {
             // If this is a show-set for an unprepared element, we need to apply
             // it.
             if !prepared {

tests/typ/compiler/show-set-text.typ

@@ -0,0 +1,41 @@
+// Text show-set rules are weird.
+
+---
+#show "He": set text(red)
+#show "ya": set text(blue)
+Heya
+
+---
+#show "Heya": set text(red)
+#show   "ya": set text(blue)
+Heya
+
+---
+#show "He": set text(red)
+#show "Heya": set text(blue)
+Heya
+
+---
+#show "Heya": set text(red)
+#show   "yaho": set text(blue)
+Heyaho
+
+---
+#show "He": set text(red)
+#show "ya": set text(weight: "bold")
+Heya
+
+---
+#show "Heya": set text(red)
+#show   "ya": set text(weight: "bold")
+Heya
+
+---
+#show "He": set text(red)
+#show "Heya": set text(weight: "bold")
+Heya
+
+---
+#show "Heya": set text(red)
+#show   "yaho": set text(weight: "bold")
+Heyaho