From 8445e75d6f3521daeec9d3195faa1916b09c34c6 Mon Sep 17 00:00:00 2001
From: sdghchj <sdghchj@qq.com>
Date: Tue, 21 Mar 2023 06:34:11 +0800
Subject: [PATCH] fix generic type that has more than 2 params with only one
 constraint type (#1506)

* fix generic type that has more than 2 params with only one constraint type

* modify test unit

Signed-off-by: sdghchj <sdghchj@qq.com>

---------

Signed-off-by: sdghchj <sdghchj@qq.com>
---
 generics.go                           | 26 +++++++++++++++++++++-----
 testdata/generics_basic/api/api.go    |  8 ++++++++
 testdata/generics_basic/expected.json | 20 ++++++++++++++++++++
 3 files changed, 49 insertions(+), 5 deletions(-)

diff --git a/generics.go b/generics.go
index 8a64cd389..c14b3ab01 100644
--- a/generics.go
+++ b/generics.go
@@ -19,6 +19,11 @@ type genericTypeSpec struct {
 	Name       string
 }
 
+type formalParamType struct {
+	Name string
+	Type string
+}
+
 func (t *genericTypeSpec) TypeName() string {
 	if t.TypeSpec != nil {
 		return t.TypeSpec.TypeName()
@@ -36,10 +41,21 @@ func (pkgDefs *PackagesDefinitions) parametrizeGenericType(file *ast.File, origi
 		return nil
 	}
 
-	genericParamTypeDefs := map[string]*genericTypeSpec{}
-	if len(genericParams) != len(original.TypeSpec.TypeParams.List) {
+	//generic[x,y any,z any] considered, TODO what if the type is not `any`, but a concrete one, such as `int32|int64` or an certain interface{}
+	var formals []formalParamType
+	for _, field := range original.TypeSpec.TypeParams.List {
+		for _, ident := range field.Names {
+			formal := formalParamType{Name: ident.Name}
+			if ident, ok := field.Type.(*ast.Ident); ok {
+				formal.Type = ident.Name
+			}
+			formals = append(formals, formal)
+		}
+	}
+	if len(genericParams) != len(formals) {
 		return nil
 	}
+	genericParamTypeDefs := map[string]*genericTypeSpec{}
 
 	for i, genericParam := range genericParams {
 		arrayDepth := 0
@@ -59,7 +75,7 @@ func (pkgDefs *PackagesDefinitions) parametrizeGenericType(file *ast.File, origi
 			}
 		}
 
-		genericParamTypeDefs[original.TypeSpec.TypeParams.List[i].Names[0].Name] = &genericTypeSpec{
+		genericParamTypeDefs[formals[i].Name] = &genericTypeSpec{
 			ArrayDepth: arrayDepth,
 			TypeSpec:   typeDef,
 			Name:       genericParam,
@@ -68,8 +84,8 @@ func (pkgDefs *PackagesDefinitions) parametrizeGenericType(file *ast.File, origi
 
 	name = fmt.Sprintf("%s%s-", string(IgnoreNameOverridePrefix), original.TypeName())
 	var nameParts []string
-	for _, def := range original.TypeSpec.TypeParams.List {
-		if specDef, ok := genericParamTypeDefs[def.Names[0].Name]; ok {
+	for _, def := range formals {
+		if specDef, ok := genericParamTypeDefs[def.Name]; ok {
 			var prefix = ""
 			if specDef.ArrayDepth == 1 {
 				prefix = "array_"
diff --git a/testdata/generics_basic/api/api.go b/testdata/generics_basic/api/api.go
index 629d4ecb6..eecd72f03 100644
--- a/testdata/generics_basic/api/api.go
+++ b/testdata/generics_basic/api/api.go
@@ -14,6 +14,13 @@ type Response[T any, X any] struct {
 	Status string
 }
 
+type Response2[T, X any, Y any] struct {
+	Data T
+	Meta X
+
+	Status Y
+}
+
 type StringStruct struct {
 	Data string
 }
@@ -31,6 +38,7 @@ type Foo = web.GenericResponseMulti[types.Post, types.Post]
 // @Success 203 {object} web.GenericResponse[types.Field[int]]
 // @Success 204 {object} Response[string, types.Field[int]]
 // @Success 205 {object} Response[StringStruct, types.Field[int]]
+// @Success 206 {object} Response2[string, types.Field[int],string]
 // @Success 222 {object} web.GenericResponseMulti[types.Post, types.Post]
 // @Failure 400 {object} web.APIError "We need ID!!"
 // @Failure 404 {object} web.APIError "Can not find ID"
diff --git a/testdata/generics_basic/expected.json b/testdata/generics_basic/expected.json
index 6eca46ed9..ac5ecc222 100644
--- a/testdata/generics_basic/expected.json
+++ b/testdata/generics_basic/expected.json
@@ -165,6 +165,12 @@
                             "$ref": "#/definitions/api.Response-api_StringStruct-types_Field-int"
                         }
                     },
+                    "206": {
+                        "description": "Partial Content",
+                        "schema": {
+                            "$ref": "#/definitions/api.Response2-string-types_Field-int-string"
+                        }
+                    },
                     "222": {
                         "description": "",
                         "schema": {
@@ -230,6 +236,20 @@
                 }
             }
         },
+        "api.Response2-string-types_Field-int-string": {
+            "type": "object",
+            "properties": {
+                "data": {
+                    "type": "string"
+                },
+                "meta": {
+                    "$ref": "#/definitions/types.Field-int"
+                },
+                "status": {
+                    "type": "string"
+                }
+            }
+        },
         "api.StringStruct": {
             "type": "object",
             "properties": {