1 files changed, 111 insertions, 0 deletions

diff --git a/crates/ide/src/display/short_label.rs b/crates/ide/src/display/short_label.rs
new file mode 100644
index 000000000..ea49d9f97
--- /dev/null
+++ b/crates/ide/src/display/short_label.rs
@@ -0,0 +1,111 @@
+//! FIXME: write short doc here
+
+use stdx::format_to;
+use syntax::ast::{self, AstNode, NameOwner, VisibilityOwner};
+
+pub(crate) trait ShortLabel {
+    fn short_label(&self) -> Option<String>;
+}
+
+impl ShortLabel for ast::Fn {
+    fn short_label(&self) -> Option<String> {
+        Some(crate::display::function_declaration(self))
+    }
+}
+
+impl ShortLabel for ast::Struct {
+    fn short_label(&self) -> Option<String> {
+        short_label_from_node(self, "struct ")
+    }
+}
+
+impl ShortLabel for ast::Union {
+    fn short_label(&self) -> Option<String> {
+        short_label_from_node(self, "union ")
+    }
+}
+
+impl ShortLabel for ast::Enum {
+    fn short_label(&self) -> Option<String> {
+        short_label_from_node(self, "enum ")
+    }
+}
+
+impl ShortLabel for ast::Trait {
+    fn short_label(&self) -> Option<String> {
+        if self.unsafe_token().is_some() {
+            short_label_from_node(self, "unsafe trait ")
+        } else {
+            short_label_from_node(self, "trait ")
+        }
+    }
+}
+
+impl ShortLabel for ast::Module {
+    fn short_label(&self) -> Option<String> {
+        short_label_from_node(self, "mod ")
+    }
+}
+
+impl ShortLabel for ast::SourceFile {
+    fn short_label(&self) -> Option<String> {
+        None
+    }
+}
+
+impl ShortLabel for ast::TypeAlias {
+    fn short_label(&self) -> Option<String> {
+        short_label_from_node(self, "type ")
+    }
+}
+
+impl ShortLabel for ast::Const {
+    fn short_label(&self) -> Option<String> {
+        let mut new_buf = short_label_from_ty(self, self.ty(), "const ")?;
+        if let Some(expr) = self.body() {
+            format_to!(new_buf, " = {}", expr.syntax());
+        }
+        Some(new_buf)
+    }
+}
+
+impl ShortLabel for ast::Static {
+    fn short_label(&self) -> Option<String> {
+        short_label_from_ty(self, self.ty(), "static ")
+    }
+}
+
+impl ShortLabel for ast::RecordField {
+    fn short_label(&self) -> Option<String> {
+        short_label_from_ty(self, self.ty(), "")
+    }
+}
+
+impl ShortLabel for ast::Variant {
+    fn short_label(&self) -> Option<String> {
+        Some(self.name()?.text().to_string())
+    }
+}
+
+fn short_label_from_ty<T>(node: &T, ty: Option<ast::Type>, prefix: &str) -> Option<String>
+where
+    T: NameOwner + VisibilityOwner,
+{
+    let mut buf = short_label_from_node(node, prefix)?;
+
+    if let Some(type_ref) = ty {
+        format_to!(buf, ": {}", type_ref.syntax());
+    }
+
+    Some(buf)
+}
+
+fn short_label_from_node<T>(node: &T, label: &str) -> Option<String>
+where
+    T: NameOwner + VisibilityOwner,
+{
+    let mut buf = node.visibility().map(|v| format!("{} ", v.syntax())).unwrap_or_default();
+    buf.push_str(label);
+    buf.push_str(node.name()?.text().as_str());
+    Some(buf)
+}