Fix template function DateTime (#24317)

Before, 500 error


![image](https://user-images.githubusercontent.com/2114189/234170176-403ffd1b-ec27-42be-bff9-86184dc8d74d.png)

3 files changed, 89 insertions, 9 deletions

diff --git a/modules/timeutil/datetime.go b/modules/timeutil/datetime.go
index 02275bca0c..80b96fa656 100644
--- a/modules/timeutil/datetime.go
+++ b/modules/timeutil/datetime.go
@@ -7,19 +7,54 @@ import (
 	"fmt"
 	"html"
 	"html/template"
+	"time"
 )
 
-// DateTime renders an absolute time HTML given a time as a string
-func DateTime(format, datetime, fallback string) template.HTML {
-	datetimeEscaped := html.EscapeString(datetime)
-	fallbackEscaped := html.EscapeString(fallback)
+// DateTime renders an absolute time HTML element by datetime.
+func DateTime(format string, datetime any) template.HTML {
+	if p, ok := datetime.(*time.Time); ok {
+		datetime = *p
+	}
+	if p, ok := datetime.(*TimeStamp); ok {
+		datetime = *p
+	}
+	switch v := datetime.(type) {
+	case TimeStamp:
+		datetime = v.AsTime()
+	case int:
+		datetime = TimeStamp(v).AsTime()
+	case int64:
+		datetime = TimeStamp(v).AsTime()
+	}
+
+	var datetimeEscaped, textEscaped string
+	switch v := datetime.(type) {
+	case nil:
+		return "N/A"
+	case string:
+		datetimeEscaped = html.EscapeString(v)
+		textEscaped = datetimeEscaped
+	case time.Time:
+		if v.IsZero() || v.Unix() == 0 {
+			return "N/A"
+		}
+		datetimeEscaped = html.EscapeString(v.Format(time.RFC3339))
+		if format == "full" {
+			textEscaped = html.EscapeString(v.Format("2006-01-02 15:04:05 -07:00"))
+		} else {
+			textEscaped = html.EscapeString(v.Format("2006-01-02"))
+		}
+	default:
+		panic(fmt.Sprintf("Unsupported time type %T", datetime))
+	}
+
 	switch format {
 	case "short":
-		return template.HTML(fmt.Sprintf(`<relative-time format="datetime" year="numeric" month="short" day="numeric" weekday="" datetime="%s">%s</relative-time>`, datetimeEscaped, fallbackEscaped))
+		return template.HTML(fmt.Sprintf(`<relative-time format="datetime" year="numeric" month="short" day="numeric" weekday="" datetime="%s">%s</relative-time>`, datetimeEscaped, textEscaped))
 	case "long":
-		return template.HTML(fmt.Sprintf(`<relative-time format="datetime" year="numeric" month="long" day="numeric" weekday="" datetime="%s">%s</relative-time>`, datetimeEscaped, fallbackEscaped))
+		return template.HTML(fmt.Sprintf(`<relative-time format="datetime" year="numeric" month="long" day="numeric" weekday="" datetime="%s">%s</relative-time>`, datetimeEscaped, textEscaped))
 	case "full":
-		return template.HTML(fmt.Sprintf(`<relative-time format="datetime" weekday="" year="numeric" month="short" day="numeric" hour="numeric" minute="numeric" second="numeric" datetime="%s">%s</relative-time>`, datetimeEscaped, fallbackEscaped))
+		return template.HTML(fmt.Sprintf(`<relative-time format="datetime" weekday="" year="numeric" month="short" day="numeric" hour="numeric" minute="numeric" second="numeric" datetime="%s">%s</relative-time>`, datetimeEscaped, textEscaped))
 	}
-	return template.HTML("error in DateTime")
+	panic(fmt.Sprintf("Unsupported format %s", format))
 }
diff --git a/modules/timeutil/datetime_test.go b/modules/timeutil/datetime_test.go
new file mode 100644
index 0000000000..a5639b34f1
--- /dev/null
+++ b/modules/timeutil/datetime_test.go
@@ -0,0 +1,45 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package timeutil
+
+import (
+	"testing"
+	"time"
+
+	"code.gitea.io/gitea/modules/setting"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDateTime(t *testing.T) {
+	oldTz := setting.DefaultUILocation
+	setting.DefaultUILocation, _ = time.LoadLocation("America/New_York")
+	defer func() {
+		setting.DefaultUILocation = oldTz
+	}()
+
+	refTimeStr := "2018-01-01T00:00:00Z"
+	refTime, _ := time.Parse(time.RFC3339, refTimeStr)
+	refTimeStamp := TimeStamp(refTime.Unix())
+
+	assert.EqualValues(t, "N/A", DateTime("short", nil))
+	assert.EqualValues(t, "N/A", DateTime("short", 0))
+	assert.EqualValues(t, "N/A", DateTime("short", time.Time{}))
+	assert.EqualValues(t, "N/A", DateTime("short", TimeStamp(0)))
+
+	actual := DateTime("short", "invalid")
+	assert.EqualValues(t, `<relative-time format="datetime" year="numeric" month="short" day="numeric" weekday="" datetime="invalid">invalid</relative-time>`, actual)
+
+	actual = DateTime("short", refTimeStr)
+	assert.EqualValues(t, `<relative-time format="datetime" year="numeric" month="short" day="numeric" weekday="" datetime="2018-01-01T00:00:00Z">2018-01-01T00:00:00Z</relative-time>`, actual)
+
+	actual = DateTime("short", refTime)
+	assert.EqualValues(t, `<relative-time format="datetime" year="numeric" month="short" day="numeric" weekday="" datetime="2018-01-01T00:00:00Z">2018-01-01</relative-time>`, actual)
+
+	actual = DateTime("short", refTimeStamp)
+	assert.EqualValues(t, `<relative-time format="datetime" year="numeric" month="short" day="numeric" weekday="" datetime="2017-12-31T19:00:00-05:00">2017-12-31</relative-time>`, actual)
+
+	actual = DateTime("full", refTimeStamp)
+	assert.EqualValues(t, `<relative-time format="datetime" weekday="" year="numeric" month="short" day="numeric" hour="numeric" minute="numeric" second="numeric" datetime="2017-12-31T19:00:00-05:00">2017-12-31 19:00:00 -05:00</relative-time>`, actual)
+}
diff --git a/modules/timeutil/since.go b/modules/timeutil/since.go
index 4aee814ecd..04fcff54a3 100644
--- a/modules/timeutil/since.go
+++ b/modules/timeutil/since.go
@@ -115,7 +115,7 @@ func timeSincePro(then, now time.Time, lang translation.Locale) string {
 }
 
 func timeSinceUnix(then, now time.Time, lang translation.Locale) template.HTML {
-	friendlyText := then.Format("2006-01-02 15:04:05 +07:00")
+	friendlyText := then.Format("2006-01-02 15:04:05 -07:00")
 
 	// document: https://github.com/github/relative-time-element
 	attrs := `tense="past"`