From 4bf848a06bfa069e5f381235193924f2b35f2d9d Mon Sep 17 00:00:00 2001
From: wxiaoguang <wxiaoguang@gmail.com>
Date: Tue, 11 Jun 2024 22:52:12 +0800
Subject: [PATCH] Make template `Iif` exactly match `if` (#31322)

---
 modules/templates/helper.go      | 16 +++++-----
 modules/templates/helper_test.go | 52 ++++++++++++++++++++++++--------
 2 files changed, 47 insertions(+), 21 deletions(-)

diff --git a/modules/templates/helper.go b/modules/templates/helper.go
index 8779de69ca..330cbf8908 100644
--- a/modules/templates/helper.go
+++ b/modules/templates/helper.go
@@ -239,7 +239,7 @@ func DotEscape(raw string) string {
 // Iif is an "inline-if", similar util.Iif[T] but templates need the non-generic version,
 // and it could be simply used as "{{Iif expr trueVal}}" (omit the falseVal).
 func Iif(condition any, vals ...any) any {
-	if IsTruthy(condition) {
+	if isTemplateTruthy(condition) {
 		return vals[0]
 	} else if len(vals) > 1 {
 		return vals[1]
@@ -247,7 +247,7 @@ func Iif(condition any, vals ...any) any {
 	return nil
 }
 
-func IsTruthy(v any) bool {
+func isTemplateTruthy(v any) bool {
 	if v == nil {
 		return false
 	}
@@ -256,20 +256,20 @@ func IsTruthy(v any) bool {
 	switch rv.Kind() {
 	case reflect.Bool:
 		return rv.Bool()
-	case reflect.String:
-		return rv.String() != ""
 	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
 		return rv.Int() != 0
 	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
 		return rv.Uint() != 0
 	case reflect.Float32, reflect.Float64:
 		return rv.Float() != 0
-	case reflect.Slice, reflect.Array, reflect.Map:
+	case reflect.Complex64, reflect.Complex128:
+		return rv.Complex() != 0
+	case reflect.String, reflect.Slice, reflect.Array, reflect.Map:
 		return rv.Len() > 0
-	case reflect.Ptr:
-		return !rv.IsNil() && IsTruthy(reflect.Indirect(rv).Interface())
+	case reflect.Struct:
+		return true
 	default:
-		return rv.Kind() == reflect.Struct && !rv.IsNil()
+		return !rv.IsNil()
 	}
 }
 
diff --git a/modules/templates/helper_test.go b/modules/templates/helper_test.go
index c6c70cc18e..ea5da7be80 100644
--- a/modules/templates/helper_test.go
+++ b/modules/templates/helper_test.go
@@ -5,8 +5,11 @@ package templates
 
 import (
 	"html/template"
+	"strings"
 	"testing"
 
+	"code.gitea.io/gitea/modules/util"
+
 	"github.com/stretchr/testify/assert"
 )
 
@@ -66,17 +69,40 @@ func TestSanitizeHTML(t *testing.T) {
 	assert.Equal(t, template.HTML(`<a href="/" rel="nofollow">link</a> xss <div>inline</div>`), SanitizeHTML(`<a href="/">link</a> <a href="javascript:">xss</a> <div style="dangerous">inline</div>`))
 }
 
-func TestIsTruthy(t *testing.T) {
-	var test any
-	assert.Equal(t, false, IsTruthy(test))
-	assert.Equal(t, false, IsTruthy(nil))
-	assert.Equal(t, false, IsTruthy(""))
-	assert.Equal(t, true, IsTruthy("non-empty"))
-	assert.Equal(t, true, IsTruthy(-1))
-	assert.Equal(t, false, IsTruthy(0))
-	assert.Equal(t, true, IsTruthy(42))
-	assert.Equal(t, false, IsTruthy(0.0))
-	assert.Equal(t, true, IsTruthy(3.14))
-	assert.Equal(t, false, IsTruthy([]int{}))
-	assert.Equal(t, true, IsTruthy([]int{1}))
+func TestTemplateTruthy(t *testing.T) {
+	tmpl := template.New("test")
+	tmpl.Funcs(template.FuncMap{"Iif": Iif})
+	template.Must(tmpl.Parse(`{{if .Value}}true{{else}}false{{end}}:{{Iif .Value "true" "false"}}`))
+
+	cases := []any{
+		nil, false, true, "", "string", 0, 1,
+		byte(0), byte(1), int64(0), int64(1), float64(0), float64(1),
+		complex(0, 0), complex(1, 0),
+		(chan int)(nil), make(chan int),
+		(func())(nil), func() {},
+		util.ToPointer(0), util.ToPointer(util.ToPointer(0)),
+		util.ToPointer(1), util.ToPointer(util.ToPointer(1)),
+		[0]int{},
+		[1]int{0},
+		[]int(nil),
+		[]int{},
+		[]int{0},
+		map[any]any(nil),
+		map[any]any{},
+		map[any]any{"k": "v"},
+		(*struct{})(nil),
+		struct{}{},
+		util.ToPointer(struct{}{}),
+	}
+	w := &strings.Builder{}
+	truthyCount := 0
+	for i, v := range cases {
+		w.Reset()
+		assert.NoError(t, tmpl.Execute(w, struct{ Value any }{v}), "case %d (%T) %#v fails", i, v, v)
+		out := w.String()
+		truthyCount += util.Iif(out == "true:true", 1, 0)
+		truthyMatches := out == "true:true" || out == "false:false"
+		assert.True(t, truthyMatches, "case %d (%T) %#v fail: %s", i, v, v, out)
+	}
+	assert.True(t, truthyCount != 0 && truthyCount != len(cases))
 }