From d476d65f7ba921f0080e0175a6a316d4e483157b Mon Sep 17 00:00:00 2001
From: Krouton <hi.im.knium@gmail.com>
Date: Mon, 30 Mar 2020 23:21:31 +0900
Subject: [PATCH] Parse parenthesized parameter-type. (#421)

Add test.
---
 .../parenthesized_parameter_type/README.md    |  3 ++
 .../parenthesized_parameter_type/input.go     |  5 +++
 .../parenthesized_parameter_type/mock.go      | 45 +++++++++++++++++++
 mockgen/parse.go                              |  2 +
 4 files changed, 55 insertions(+)
 create mode 100644 mockgen/internal/tests/parenthesized_parameter_type/README.md
 create mode 100644 mockgen/internal/tests/parenthesized_parameter_type/input.go
 create mode 100644 mockgen/internal/tests/parenthesized_parameter_type/mock.go

diff --git a/mockgen/internal/tests/parenthesized_parameter_type/README.md b/mockgen/internal/tests/parenthesized_parameter_type/README.md
new file mode 100644
index 00000000..fc816bdf
--- /dev/null
+++ b/mockgen/internal/tests/parenthesized_parameter_type/README.md
@@ -0,0 +1,3 @@
+# Parenthesized Parameter Type
+
+Test for [Issue#416](https://github.com/golang/mock/issues/416).
diff --git a/mockgen/internal/tests/parenthesized_parameter_type/input.go b/mockgen/internal/tests/parenthesized_parameter_type/input.go
new file mode 100644
index 00000000..b9be61bd
--- /dev/null
+++ b/mockgen/internal/tests/parenthesized_parameter_type/input.go
@@ -0,0 +1,5 @@
+package parenthesized_parameter_type
+
+type Example interface {
+	ParenthesizedParameterType(param *(int))
+}
diff --git a/mockgen/internal/tests/parenthesized_parameter_type/mock.go b/mockgen/internal/tests/parenthesized_parameter_type/mock.go
new file mode 100644
index 00000000..911df8d8
--- /dev/null
+++ b/mockgen/internal/tests/parenthesized_parameter_type/mock.go
@@ -0,0 +1,45 @@
+// Code generated by MockGen. DO NOT EDIT.
+// Source: ./mockgen/internal/tests/parenthesized_parameter_type/input.go
+
+// Package parenthesized_parameter_type is a generated GoMock package.
+package parenthesized_parameter_type
+
+import (
+	gomock "github.com/golang/mock/gomock"
+	reflect "reflect"
+)
+
+// MockExample is a mock of Example interface.
+type MockExample struct {
+	ctrl     *gomock.Controller
+	recorder *MockExampleMockRecorder
+}
+
+// MockExampleMockRecorder is the mock recorder for MockExample.
+type MockExampleMockRecorder struct {
+	mock *MockExample
+}
+
+// NewMockExample creates a new mock instance.
+func NewMockExample(ctrl *gomock.Controller) *MockExample {
+	mock := &MockExample{ctrl: ctrl}
+	mock.recorder = &MockExampleMockRecorder{mock}
+	return mock
+}
+
+// EXPECT returns an object that allows the caller to indicate expected use.
+func (m *MockExample) EXPECT() *MockExampleMockRecorder {
+	return m.recorder
+}
+
+// ParenthesizedParameterType mocks base method.
+func (m *MockExample) ParenthesizedParameterType(param *int) {
+	m.ctrl.T.Helper()
+	m.ctrl.Call(m, "ParenthesizedParameterType", param)
+}
+
+// ParenthesizedParameterType indicates an expected call of ParenthesizedParameterType.
+func (mr *MockExampleMockRecorder) ParenthesizedParameterType(param interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "ParenthesizedParameterType", reflect.TypeOf((*MockExample)(nil).ParenthesizedParameterType), param)
+}
diff --git a/mockgen/parse.go b/mockgen/parse.go
index 7f1a433c..f47a3d9a 100644
--- a/mockgen/parse.go
+++ b/mockgen/parse.go
@@ -424,6 +424,8 @@ func (p *fileParser) parseType(pkg string, typ ast.Expr) (model.Type, error) {
 			return nil, p.errorf(v.Pos(), "can't handle non-empty unnamed struct types")
 		}
 		return model.PredeclaredType("struct{}"), nil
+	case *ast.ParenExpr:
+		return p.parseType(pkg, v.X)
 	}
 
 	return nil, fmt.Errorf("don't know how to parse type %T", typ)