Fix for issue #811 (falsely inserted "::" in paths with parameterized trait cast).

src/types.rs

@@ -53,7 +53,7 @@ pub fn rewrite_path(context: &RewriteContext,
             // 3 = ">::".len()
             let budget = try_opt!(width.checked_sub(extra_offset + 3));
 
-            result = try_opt!(rewrite_path_segments(expr_context,
+            result = try_opt!(rewrite_path_segments(false,
                                                     result,
                                                     path.segments.iter().take(skip_count),
                                                     span_lo,

tests/source/issue-811.rs

@@ -0,0 +1,19 @@
+trait FooTrait<T>: Sized {
+    type Bar: BarTrait<T>;
+}
+
+trait BarTrait<T>: Sized {
+    type Baz;
+    fn foo();
+}
+
+type Foo<T: FooTrait> = <<T as FooTrait<U>>::Bar as BarTrait<U>>::Baz;
+type Bar<T: BarTrait> = <T as BarTrait<U>>::Baz;
+
+fn some_func<T: FooTrait<U>, U>() {
+    <<T as FooTrait<U>>::Bar as BarTrait<U>>::foo();
+}
+
+fn some_func<T: BarTrait<U>>() {
+    <T as BarTrait<U>>::foo();
+}

tests/target/issue-811.rs

@@ -0,0 +1,20 @@
+trait FooTrait<T>: Sized {
+    type Bar: BarTrait<T>;
+}
+
+trait BarTrait<T>: Sized {
+    type Baz;
+    fn foo();
+}
+
+type Foo<T: FooTrait> =
+    <<T as FooTrait<U>>::Bar as BarTrait<U>>::Baz;
+type Bar<T: BarTrait> = <T as BarTrait<U>>::Baz;
+
+fn some_func<T: FooTrait<U>, U>() {
+    <<T as FooTrait<U>>::Bar as BarTrait<U>>::foo();
+}
+
+fn some_func<T: BarTrait<U>>() {
+    <T as BarTrait<U>>::foo();
+}