1 files changed, 61 insertions, 6 deletions

diff --git a/crates/ra_macros/src/tt.rs b/crates/ra_macros/src/tt.rs
index 364eed9e6..56e930f00 100644
--- a/crates/ra_macros/src/tt.rs
+++ b/crates/ra_macros/src/tt.rs
@@ -1,13 +1,16 @@
+use std::fmt;
+
 use smol_str::SmolStr;
+use join_to_string::join;
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub enum TokenTree {
     Leaf(Leaf),
     Subtree(Subtree),
 }
 impl_froms!(TokenTree: Leaf, Subtree);
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub enum Leaf {
     Literal(Literal),
     Punct(Punct),
@@ -15,7 +18,7 @@ pub enum Leaf {
 }
 impl_froms!(Leaf: Literal, Punct, Ident);
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct Subtree {
     pub delimiter: Delimiter,
     pub token_trees: Vec<TokenTree>,
@@ -29,17 +32,69 @@ pub enum Delimiter {
     None,
 }
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct Literal {
     pub text: SmolStr,
 }
 
-#[derive(Debug)]
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Punct {
     pub char: char,
 }
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct Ident {
     pub text: SmolStr,
 }
+
+impl fmt::Display for TokenTree {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            TokenTree::Leaf(it) => fmt::Display::fmt(it, f),
+            TokenTree::Subtree(it) => fmt::Display::fmt(it, f),
+        }
+    }
+}
+
+impl fmt::Display for Subtree {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let (l, r) = match self.delimiter {
+            Delimiter::Parenthesis => ("(", ")"),
+            Delimiter::Brace => ("{", "}"),
+            Delimiter::Bracket => ("[", "]"),
+            Delimiter::None => ("", ""),
+        };
+        join(self.token_trees.iter())
+            .separator(" ")
+            .surround_with(l, r)
+            .to_fmt(f)
+    }
+}
+
+impl fmt::Display for Leaf {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            Leaf::Ident(it) => fmt::Display::fmt(it, f),
+            Leaf::Literal(it) => fmt::Display::fmt(it, f),
+            Leaf::Punct(it) => fmt::Display::fmt(it, f),
+        }
+    }
+}
+
+impl fmt::Display for Ident {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        fmt::Display::fmt(&self.text, f)
+    }
+}
+
+impl fmt::Display for Literal {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        fmt::Display::fmt(&self.text, f)
+    }
+}
+
+impl fmt::Display for Punct {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        fmt::Display::fmt(&self.char, f)
+    }
+}