7 files changed, 112 insertions, 57 deletions

diff --git a/crates/ra_ide_api/src/completion/complete_path.rs b/crates/ra_ide_api/src/completion/complete_path.rs
index 804954ee1..6bed299d2 100644
--- a/crates/ra_ide_api/src/completion/complete_path.rs
+++ b/crates/ra_ide_api/src/completion/complete_path.rs
@@ -121,30 +121,4 @@ mod tests {
             ",
         );
     }
-
-    #[test]
-    fn dont_render_function_parens_in_use_item() {
-        check_reference_completion(
-            "dont_render_function_parens_in_use_item",
-            "
-            //- /lib.rs
-            mod m { pub fn foo() {} }
-            use crate::m::f<|>;
-            ",
-        )
-    }
-
-    #[test]
-    fn dont_render_function_parens_if_already_call() {
-        check_reference_completion(
-            "dont_render_function_parens_if_already_call",
-            "
-            //- /lib.rs
-            fn frobnicate() {}
-            fn main() {
-                frob<|>();
-            }
-            ",
-        )
-    }
 }
diff --git a/crates/ra_ide_api/src/completion/complete_scope.rs b/crates/ra_ide_api/src/completion/complete_scope.rs
index 20fc77f06..f837bb1db 100644
--- a/crates/ra_ide_api/src/completion/complete_scope.rs
+++ b/crates/ra_ide_api/src/completion/complete_scope.rs
@@ -175,21 +175,4 @@ mod tests {
         check_reference_completion("self_in_methods", r"impl S { fn foo(&self) { <|> } }")
     }
 
-    #[test]
-    fn inserts_parens_for_function_calls() {
-        check_reference_completion(
-            "inserts_parens_for_function_calls1",
-            r"
-            fn no_args() {}
-            fn main() { no_<|> }
-            ",
-        );
-        check_reference_completion(
-            "inserts_parens_for_function_calls2",
-            r"
-            fn with_args(x: i32, y: String) {}
-            fn main() { with_<|> }
-            ",
-        );
-    }
 }
diff --git a/crates/ra_ide_api/src/completion/completion_item.rs b/crates/ra_ide_api/src/completion/completion_item.rs
index 680fd8d1b..e3bf82304 100644
--- a/crates/ra_ide_api/src/completion/completion_item.rs
+++ b/crates/ra_ide_api/src/completion/completion_item.rs
@@ -3,9 +3,10 @@ use hir::PerNs;
 use crate::completion::completion_context::CompletionContext;
 use ra_syntax::{
     ast::{self, AstNode},
-    TextRange
+    TextRange,
 };
 use ra_text_edit::TextEdit;
+use test_utils::tested_by;
 
 /// `CompletionItem` describes a single completion variant in the editor pop-up.
 /// It is basically a POD with various properties. To construct a
@@ -255,7 +256,9 @@ impl Builder {
     ) -> Builder {
         // If not an import, add parenthesis automatically.
         if ctx.use_item_syntax.is_none() && !ctx.is_call {
-            if function.signature(ctx.db).params().is_empty() {
+            tested_by!(inserts_parens_for_function_calls);
+            let sig = function.signature(ctx.db);
+            if sig.params().is_empty() || sig.has_self_param() && sig.params().len() == 1 {
                 self.insert_text = Some(format!("{}()$0", self.label));
             } else {
                 self.insert_text = Some(format!("{}($0)", self.label));
@@ -344,3 +347,72 @@ pub(crate) fn check_completion(test_name: &str, code: &str, kind: CompletionKind
         .collect();
     assert_debug_snapshot_matches!(test_name, kind_completions);
 }
+
+#[cfg(test)]
+mod tests {
+    use test_utils::covers;
+
+    use super::*;
+
+    fn check_reference_completion(code: &str, expected_completions: &str) {
+        check_completion(code, expected_completions, CompletionKind::Reference);
+    }
+
+    #[test]
+    fn inserts_parens_for_function_calls() {
+        covers!(inserts_parens_for_function_calls);
+        check_reference_completion(
+            "inserts_parens_for_function_calls1",
+            r"
+            fn no_args() {}
+            fn main() { no_<|> }
+            ",
+        );
+        check_reference_completion(
+            "inserts_parens_for_function_calls2",
+            r"
+            fn with_args(x: i32, y: String) {}
+            fn main() { with_<|> }
+            ",
+        );
+        check_reference_completion(
+            "inserts_parens_for_function_calls3",
+            r"
+            struct S {}
+            impl S {
+                fn foo(&self) {}
+            }
+            fn bar(s: &S) {
+                s.f<|>
+            }
+            ",
+        )
+    }
+
+    #[test]
+    fn dont_render_function_parens_in_use_item() {
+        check_reference_completion(
+            "dont_render_function_parens_in_use_item",
+            "
+            //- /lib.rs
+            mod m { pub fn foo() {} }
+            use crate::m::f<|>;
+            ",
+        )
+    }
+
+    #[test]
+    fn dont_render_function_parens_if_already_call() {
+        check_reference_completion(
+            "dont_render_function_parens_if_already_call",
+            "
+            //- /lib.rs
+            fn frobnicate() {}
+            fn main() {
+                frob<|>();
+            }
+            ",
+        )
+    }
+
+}
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__inserts_parens_for_function_calls3.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__inserts_parens_for_function_calls3.snap
new file mode 100644
index 000000000..92068e50a
--- /dev/null
+++ b/crates/ra_ide_api/src/completion/snapshots/completion_item__inserts_parens_for_function_calls3.snap
@@ -0,0 +1,26 @@
+---
+created: "2019-01-23T13:19:23.525922020+00:00"
+creator: [email protected]
+expression: kind_completions
+source: crates/ra_ide_api/src/completion/completion_item.rs
+---
+[
+    CompletionItem {
+        completion_kind: Reference,
+        label: "foo",
+        kind: Some(
+            Method
+        ),
+        detail: Some(
+            "fn foo(&self)"
+        ),
+        documentation: None,
+        lookup: None,
+        insert_text: Some(
+            "foo()$0"
+        ),
+        insert_text_format: Snippet,
+        source_range: [139; 140),
+        text_edit: None
+    }
+]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__method_completion.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__method_completion.snap
index ffeac0bf4..10fe59248 100644
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__method_completion.snap
+++ b/crates/ra_ide_api/src/completion/snapshots/completion_item__method_completion.snap
@@ -1,8 +1,8 @@
 ---
-created: "2019-01-22T15:38:19.541947400+00:00"
-creator: insta@0.4.0
+created: "2019-01-23T13:19:23.501258181+00:00"
+creator: insta@0.5.2
 expression: kind_completions
-source: "crates\\ra_ide_api\\src\\completion\\completion_item.rs"
+source: crates/ra_ide_api/src/completion/completion_item.rs
 ---
 [
     CompletionItem {
@@ -17,7 +17,7 @@ source: "crates\\ra_ide_api\\src\\completion\\completion_item.rs"
         documentation: None,
         lookup: None,
         insert_text: Some(
-            "the_method($0)"
+            "the_method()$0"
         ),
         insert_text_format: Snippet,
         source_range: [144; 144),
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_autoderef.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_autoderef.snap
index 5ef140b28..5f5df0033 100644
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_autoderef.snap
+++ b/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_autoderef.snap
@@ -1,8 +1,8 @@
 ---
-created: "2019-01-22T15:38:19.541947400+00:00"
-creator: insta@0.4.0
+created: "2019-01-23T13:19:23.501353210+00:00"
+creator: insta@0.5.2
 expression: kind_completions
-source: "crates\\ra_ide_api\\src\\completion\\completion_item.rs"
+source: crates/ra_ide_api/src/completion/completion_item.rs
 ---
 [
     CompletionItem {
@@ -33,7 +33,7 @@ source: "crates\\ra_ide_api\\src\\completion\\completion_item.rs"
         documentation: None,
         lookup: None,
         insert_text: Some(
-            "foo($0)"
+            "foo()$0"
         ),
         insert_text_format: Snippet,
         source_range: [126; 126),
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_self.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_self.snap
index b7903c5bc..80e8f3df5 100644
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_self.snap
+++ b/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_self.snap
@@ -1,8 +1,8 @@
 ---
-created: "2019-01-22T15:38:19.541947400+00:00"
-creator: insta@0.4.0
+created: "2019-01-23T13:19:23.501297515+00:00"
+creator: insta@0.5.2
 expression: kind_completions
-source: "crates\\ra_ide_api\\src\\completion\\completion_item.rs"
+source: crates/ra_ide_api/src/completion/completion_item.rs
 ---
 [
     CompletionItem {
@@ -33,7 +33,7 @@ source: "crates\\ra_ide_api\\src\\completion\\completion_item.rs"
         documentation: None,
         lookup: None,
         insert_text: Some(
-            "foo($0)"
+            "foo()$0"
         ),
         insert_text_format: Snippet,
         source_range: [121; 121),