From a53b8933509eabbbf3faab6822b9a2fb0bbfc786 Mon Sep 17 00:00:00 2001
From: Erick Tryzelaar <erick.tryzelaar@gmail.com>
Date: Fri, 1 May 2015 11:11:11 -0700
Subject: [PATCH] Re-enable unquoting generics and where clauses

---
 Cargo.toml    |  8 ++++----
 src/lib.rs    | 24 ++++++++++++++++++++++++
 tests/test.rs | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 79 insertions(+), 4 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index b24d2e96..ced88a72 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,11 +1,11 @@
 [package]
 name = "quasi"
-version = "0.1.10"
+version = "0.1.11"
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>"]
 license = "MIT/Apache-2.0"
 description = "A quasi-quoting macro system"
 repository = "https://github.com/erickt/rust-quasi"
 
-[dev-dependencies.quasi_macros]
-version = "*"
-path = "quasi_macros"
+[dev-dependencies]
+aster = "*"
+quasi_macros = { version = "*", path = "quasi_macros" }
diff --git a/src/lib.rs b/src/lib.rs
index 7fb61919..b77a05e7 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -107,6 +107,30 @@ impl ToTokens for P<ast::TraitItem> {
     }
 }
 
+impl ToTokens for ast::Generics {
+    fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> {
+        use syntax::print::pprust;
+        use syntax::parse::parse_tts_from_source_str;
+
+        let s = pprust::generics_to_string(self);
+
+        parse_tts_from_source_str("<quote expansion".to_string(), s, cx.cfg(), cx.parse_sess())
+    }
+}
+
+impl ToTokens for ast::WhereClause {
+    fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> {
+        use syntax::print::pprust;
+        use syntax::parse::parse_tts_from_source_str;
+
+        let s = pprust::to_string(|s| {
+            s.print_where_clause(&self)
+        });
+
+        parse_tts_from_source_str("<quote expansion".to_string(), s, cx.cfg(), cx.parse_sess())
+    }
+}
+
 impl ToTokens for P<ast::Stmt> {
     fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> {
         vec![ast::TtToken(self.span, token::Interpolated(token::NtStmt(self.clone())))]
diff --git a/tests/test.rs b/tests/test.rs
index 078ed6cc..93c4c911 100644
--- a/tests/test.rs
+++ b/tests/test.rs
@@ -11,13 +11,16 @@
 #![feature(plugin, rustc_private)]
 #![plugin(quasi_macros)]
 
+extern crate aster;
 extern crate syntax;
 extern crate quasi;
 
+use syntax::ast;
 use syntax::ext::base::ExtCtxt;
 use syntax::ext::expand;
 use syntax::parse;
 use syntax::print::pprust;
+use syntax::owned_slice::OwnedSlice;
 
 fn make_ext_ctxt(sess: &parse::ParseSess) -> ExtCtxt {
     let info = syntax::codemap::ExpnInfo {
@@ -190,3 +193,51 @@ fn test_quote_with_macro() {
 
     assert_eq!(pprust::block_to_string(&block), "{ value!() }");
 }
+
+#[test]
+fn test_quote_with_generics_and_where_clause() {
+    let sess = parse::new_parse_sess();
+    let cx = make_ext_ctxt(&sess);
+
+    let builder = aster::AstBuilder::new();
+    let generics = builder.generics()
+        .ty_param("T")
+            .trait_bound("Clone").build()
+            .build()
+        .build();
+
+    let where_clause = ast::WhereClause {
+        id: ast::DUMMY_NODE_ID,
+        predicates: vec![
+            ast::WherePredicate::BoundPredicate(
+                ast::WhereBoundPredicate {
+                    span: syntax::codemap::DUMMY_SP,
+                    bound_lifetimes: vec![],
+                    bounded_ty: quote_ty!(&cx, T),
+                    bounds: OwnedSlice::from_vec(vec![
+                        ast::TraitTyParamBound(
+                            ast::PolyTraitRef {
+                                bound_lifetimes: vec![],
+                                trait_ref: ast::TraitRef {
+                                    path: builder.path().id("Clone").build(),
+                                    ref_id: ast::DUMMY_NODE_ID,
+                                },
+                                span: syntax::codemap::DUMMY_SP,
+                            },
+                            ast::TraitBoundModifier::None,
+                        ),
+                    ]),
+                }
+            ),
+        ],
+    };
+
+    let item = quote_item!(&cx,
+        impl $generics Clone for Foo $where_clause {}
+    ).unwrap();
+
+    assert_eq!(
+        pprust::item_to_string(&item),
+        "impl <T: Clone> Clone for Foo where T: Clone { }"
+    );
+}