From 3df59693482a0c3a7014894fef495308f872c728 Mon Sep 17 00:00:00 2001
From: Wankko Ree <wkr@wkr.moe>
Date: Wed, 16 Aug 2023 21:42:36 +0800
Subject: [PATCH] fix generic check with slice for ghttp (#2850)

---
 net/ghttp/ghttp_server_service_handler.go     |  8 +-
 ...ghttp_z_unit_feature_router_strict_test.go | 77 +++++++++++++++++++
 2 files changed, 82 insertions(+), 3 deletions(-)

diff --git a/net/ghttp/ghttp_server_service_handler.go b/net/ghttp/ghttp_server_service_handler.go
index 90a2deebd42..e0e97270390 100644
--- a/net/ghttp/ghttp_server_service_handler.go
+++ b/net/ghttp/ghttp_server_service_handler.go
@@ -213,10 +213,12 @@ func (s *Server) checkAndCreateFuncInfo(f interface{}, pkgPath, structName, meth
 
 func trimGeneric(structName string) string {
 	var (
-		leftBraceIndex  = strings.Index(structName, "[")
-		rightBraceIndex = strings.Index(structName, "]")
+		leftBraceIndex  = strings.LastIndex(structName, "[") // for generic, it is faster to start at the end than at the beginning
+		rightBraceIndex = strings.LastIndex(structName, "]")
 	)
-	if leftBraceIndex == -1 || rightBraceIndex == -1 {
+	if leftBraceIndex == -1 || rightBraceIndex == -1 { // not found '[' or ']'
+		return structName
+	} else if leftBraceIndex+1 == rightBraceIndex { // may be a slice, because generic is '[X]', not '[]'
 		return structName
 	}
 	return structName[:leftBraceIndex]
diff --git a/net/ghttp/ghttp_z_unit_feature_router_strict_test.go b/net/ghttp/ghttp_z_unit_feature_router_strict_test.go
index 74d82fda77c..664e1b49dd4 100644
--- a/net/ghttp/ghttp_z_unit_feature_router_strict_test.go
+++ b/net/ghttp/ghttp_z_unit_feature_router_strict_test.go
@@ -298,3 +298,80 @@ func Test_Custom_Slice_Type_Attribute(t *testing.T) {
 		)
 	})
 }
+
+func Test_Router_Handler_Strict_WithGeneric(t *testing.T) {
+	type TestReq struct {
+		Age int
+	}
+	type TestGeneric[T any] struct {
+		Test T
+	}
+	type Test1Res struct {
+		Age TestGeneric[int]
+	}
+	type Test2Res TestGeneric[int]
+	type TestGenericRes[T any] struct {
+		Test T
+	}
+
+	s := g.Server(guid.S())
+	s.Use(ghttp.MiddlewareHandlerResponse)
+	s.BindHandler("/test1", func(ctx context.Context, req *TestReq) (res *Test1Res, err error) {
+		return &Test1Res{
+			Age: TestGeneric[int]{
+				Test: req.Age,
+			},
+		}, nil
+	})
+	s.BindHandler("/test1_slice", func(ctx context.Context, req *TestReq) (res []Test1Res, err error) {
+		return []Test1Res{
+			Test1Res{
+				Age: TestGeneric[int]{
+					Test: req.Age,
+				},
+			},
+		}, nil
+	})
+	s.BindHandler("/test2", func(ctx context.Context, req *TestReq) (res *Test2Res, err error) {
+		return &Test2Res{
+			Test: req.Age,
+		}, nil
+	})
+	s.BindHandler("/test2_slice", func(ctx context.Context, req *TestReq) (res []Test2Res, err error) {
+		return []Test2Res{
+			Test2Res{
+				Test: req.Age,
+			},
+		}, nil
+	})
+
+	s.BindHandler("/test3", func(ctx context.Context, req *TestReq) (res *TestGenericRes[int], err error) {
+		return &TestGenericRes[int]{
+			Test: req.Age,
+		}, nil
+	})
+	s.BindHandler("/test3_slice", func(ctx context.Context, req *TestReq) (res []TestGenericRes[int], err error) {
+		return []TestGenericRes[int]{
+			TestGenericRes[int]{
+				Test: req.Age,
+			},
+		}, nil
+	})
+
+	s.SetDumpRouterMap(false)
+	s.Start()
+	defer s.Shutdown()
+
+	time.Sleep(100 * time.Millisecond)
+	gtest.C(t, func(t *gtest.T) {
+		client := g.Client()
+		client.SetPrefix(fmt.Sprintf("http://127.0.0.1:%d", s.GetListenedPort()))
+
+		t.Assert(client.GetContent(ctx, "/test1?age=1"), `{"code":0,"message":"","data":{"Age":{"Test":1}}}`)
+		t.Assert(client.GetContent(ctx, "/test1_slice?age=1"), `{"code":0,"message":"","data":[{"Age":{"Test":1}}]}`)
+		t.Assert(client.GetContent(ctx, "/test2?age=2"), `{"code":0,"message":"","data":{"Test":2}}`)
+		t.Assert(client.GetContent(ctx, "/test2_slice?age=2"), `{"code":0,"message":"","data":[{"Test":2}]}`)
+		t.Assert(client.GetContent(ctx, "/test3?age=3"), `{"code":0,"message":"","data":{"Test":3}}`)
+		t.Assert(client.GetContent(ctx, "/test3_slice?age=3"), `{"code":0,"message":"","data":[{"Test":3}]}`)
+	})
+}