grammar: fix where clause parsing

closes #205

3 files changed, 35 insertions, 1 deletions

diff --git a/crates/ra_syntax/src/grammar/type_params.rs b/crates/ra_syntax/src/grammar/type_params.rs
index 68eca0ce8..f4c98675c 100644
--- a/crates/ra_syntax/src/grammar/type_params.rs
+++ b/crates/ra_syntax/src/grammar/type_params.rs
@@ -135,7 +135,11 @@ fn where_predicate(p: &mut Parser) {
             if p.at(FOR_KW) {
                 types::for_binder(p);
             }
-            types::path_type(p);
+            if paths::is_path_start(p) || p.at(L_ANGLE) {
+                types::path_type_(p, false);
+            } else {
+                p.error("expected a type");
+            }
             if p.at(COLON) {
                 bounds(p);
             } else {
diff --git a/crates/ra_syntax/tests/data/parser/err/0027_incomplere_where_for.rs b/crates/ra_syntax/tests/data/parser/err/0027_incomplere_where_for.rs
new file mode 100644
index 000000000..2792c2084
--- /dev/null
+++ b/crates/ra_syntax/tests/data/parser/err/0027_incomplere_where_for.rs
@@ -0,0 +1,3 @@
+fn foo()
+    where for<'a>
+{}
diff --git a/crates/ra_syntax/tests/data/parser/err/0027_incomplere_where_for.txt b/crates/ra_syntax/tests/data/parser/err/0027_incomplere_where_for.txt
new file mode 100644
index 000000000..94b75a656
--- /dev/null
+++ b/crates/ra_syntax/tests/data/parser/err/0027_incomplere_where_for.txt
@@ -0,0 +1,27 @@
+ROOT@[0; 30)
+  FN_DEF@[0; 29)
+    FN_KW@[0; 2)
+    WHITESPACE@[2; 3)
+    NAME@[3; 6)
+      IDENT@[3; 6) "foo"
+    PARAM_LIST@[6; 8)
+      L_PAREN@[6; 7)
+      R_PAREN@[7; 8)
+    WHITESPACE@[8; 13)
+    WHERE_CLAUSE@[13; 26)
+      WHERE_KW@[13; 18)
+      WHITESPACE@[18; 19)
+      WHERE_PRED@[19; 26)
+        FOR_KW@[19; 22)
+        TYPE_PARAM_LIST@[22; 26)
+          L_ANGLE@[22; 23)
+          LIFETIME_PARAM@[23; 25)
+            LIFETIME@[23; 25) "'a"
+          R_ANGLE@[25; 26)
+          err: `expected a type`
+          err: `expected colon`
+    WHITESPACE@[26; 27)
+    BLOCK@[27; 29)
+      L_CURLY@[27; 28)
+      R_CURLY@[28; 29)
+  WHITESPACE@[29; 30)