5 files changed, 48 insertions, 11 deletions

diff --git a/src/parser/grammar/items/consts.rs b/src/parser/grammar/items/consts.rs
index 8117af706..5f3cf58c2 100644
--- a/src/parser/grammar/items/consts.rs
+++ b/src/parser/grammar/items/consts.rs
@@ -14,7 +14,7 @@ fn const_or_static(p: &mut Parser, kw: SyntaxKind) {
     p.eat(MUT_KW); // TODO: validator to forbid const mut
     name(p);
     p.expect(COLON);
-    types::type_ref(p);
+    types::ty(p);
     p.expect(EQ);
     expressions::expr(p);
     p.expect(SEMI);
diff --git a/src/parser/grammar/items/mod.rs b/src/parser/grammar/items/mod.rs
index 8bb821fb6..f1776e0e2 100644
--- a/src/parser/grammar/items/mod.rs
+++ b/src/parser/grammar/items/mod.rs
@@ -247,7 +247,7 @@ fn type_item(p: &mut Parser) {
     type_params::where_clause(p);
 
     p.expect(EQ);
-    types::type_ref(p);
+    types::ty(p);
     p.expect(SEMI);
 }
 
diff --git a/src/parser/grammar/items/structs.rs b/src/parser/grammar/items/structs.rs
index eca0d2e64..ad18fd270 100644
--- a/src/parser/grammar/items/structs.rs
+++ b/src/parser/grammar/items/structs.rs
@@ -89,7 +89,7 @@ fn named_fields(p: &mut Parser) {
         if p.at(IDENT) {
             name(p);
             p.expect(COLON);
-            types::type_ref(p);
+            types::ty(p);
             field.complete(p, NAMED_FIELD);
         } else {
             field.abandon(p);
@@ -105,7 +105,7 @@ fn pos_fields(p: &mut Parser) {
     while !p.at(R_PAREN) && !p.at(EOF) {
         let pos_field = p.start();
         visibility(p);
-        types::type_ref(p);
+        types::ty(p);
         pos_field.complete(p, POS_FIELD);
 
         if !p.at(R_PAREN) {
diff --git a/src/parser/grammar/type_params.rs b/src/parser/grammar/type_params.rs
index 8f62a471c..2462b260e 100644
--- a/src/parser/grammar/type_params.rs
+++ b/src/parser/grammar/type_params.rs
@@ -62,7 +62,7 @@ pub(super) fn list(p: &mut Parser) {
             }
         }
         if p.at(EQ) {
-            types::type_ref(p)
+            types::ty(p)
         }
         m.complete(p, TYPE_PARAM);
     }
diff --git a/src/parser/grammar/types.rs b/src/parser/grammar/types.rs
index c798edd08..71801d8ef 100644
--- a/src/parser/grammar/types.rs
+++ b/src/parser/grammar/types.rs
@@ -1,14 +1,51 @@
 use super::*;
 
-pub(super) fn type_ref(p: &mut Parser) {
+pub(super) fn ty(p: &mut Parser) {
     match p.current() {
-        IDENT => p.bump(),
-        L_PAREN => {
-            p.bump();
-            p.expect(R_PAREN);
-        }
+        L_PAREN => paren_or_tuple_ty(p),
+        IDENT => path_type(p),
         _ => {
             p.error("expected type");
         }
     }
 }
+
+fn paren_or_tuple_ty(p: &mut Parser) {
+    assert!(p.at(L_PAREN));
+    let m = p.start();
+    p.bump();
+    let mut n_types: u32 = 0;
+    let mut trailing_comma: bool = false;
+    while !p.at(EOF) && !p.at(R_PAREN) {
+        n_types += 1;
+        ty(p);
+        if p.eat(COMMA) {
+            trailing_comma = true;
+        } else {
+            trailing_comma = false;
+            break;
+        }
+    }
+    p.expect(R_PAREN);
+
+    let kind = if n_types == 1 && !trailing_comma {
+        // test paren_type
+        // type T = (i32);
+        PAREN_TYPE
+    } else {
+        // test unit_type
+        // type T = ();
+
+        // test singleton_tuple_type
+        // type T = (i32,);
+        TUPLE_TYPE
+    };
+    m.complete(p, kind);
+}
+
+fn path_type(p: &mut Parser) {
+    assert!(p.at(IDENT));
+    let m = p.start();
+    paths::type_path(p);
+    m.complete(p, PATH_TYPE);
+}