forgejo/modules/templates/util_date.go
Mathieu Fenniak f93d2cb261 ci: detect and prevent empty case statements in Go code (#11593)
One of the security patches released 2026-03-09 [fixed a vulnerability](d1c7b04d09) caused by a misapplication of Go `case` statements, where the implementation would have been correct if Go `case` statements automatically fall through to the next case block, but they do not.  This PR adds a semgrep rule which detects any empty `case` statement and raises an error, in order to prevent this coding mistake in the future.

For example, code like this will now trigger a build error:
```go
	switch setting.Protocol {
	case setting.HTTPUnix:
	case setting.FCGI:
	case setting.FCGIUnix:
	default:
		defaultLocalURL := string(setting.Protocol) + "://"
	}
```

Example error:
```
    cmd/web.go
   ❯❯❱ semgrep.config.forgejo-switch-empty-case
          switch has a case block with no content. This is treated as "break" by Go, but developers may
          confuse it for "fallthrough".  To fix this error, disambiguate by using "break" or
          "fallthrough".

          279┆ switch setting.Protocol {
          280┆ case setting.HTTPUnix:
          281┆ case setting.FCGI:
          282┆ case setting.FCGIUnix:
          283┆ default:
          284┆   defaultLocalURL := string(setting.Protocol) + "://"
          285┆   if setting.HTTPAddr == "0.0.0.0" {
          286┆           defaultLocalURL += "localhost"
          287┆   } else {
          288┆           defaultLocalURL += setting.HTTPAddr
```

As described in the error output, this error can be fixed by explicitly listing `break` (the real Go behaviour, to do nothing in the block), or by listing `fallthrough` (if the intent was to fall through).

All existing code triggering this detection has been changed to `break` (or, rarely, irrelevant cases have been removed), which should maintain the same code functionality.  While performing this fixup, a light analysis was performed on each case and they *appeared* correct, but with ~65 cases I haven't gone into extreme depth.

Tests are present for the semgrep rule in `.semgrep/tests/go.go`.

## Checklist

The [contributor guide](https://forgejo.org/docs/next/contributor/) contains information that will be helpful to first time contributors. There also are a few [conditions for merging Pull Requests in Forgejo repositories](https://codeberg.org/forgejo/governance/src/branch/main/PullRequestsAgreement.md). You are also welcome to join the [Forgejo development chatroom](https://matrix.to/#/#forgejo-development:matrix.org).

### Documentation

- [ ] I created a pull request [to the documentation](https://codeberg.org/forgejo/docs) to explain to Forgejo users how to use this change.
- [x] I did not document these changes and I do not expect someone else to do it.

### Release notes

- [ ] This change will be noticed by a Forgejo user or admin (feature, bug fix, performance, etc.). I suggest to include a release note for this change.
- [x] This change is not visible to a Forgejo user or admin (refactor, dependency upgrade, etc.). I think there is no need to add a release note for this change.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/11593
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: Mathieu Fenniak <mathieu@fenniak.net>
Co-committed-by: Mathieu Fenniak <mathieu@fenniak.net>
2026-03-10 02:50:28 +01:00

149 lines
4.3 KiB
Go

// Copyright 2024 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package templates
import (
"fmt"
"html"
"html/template"
"strings"
"time"
"forgejo.org/modules/setting"
"forgejo.org/modules/timeutil"
"forgejo.org/modules/translation"
)
type DateUtils struct{}
func NewDateUtils() *DateUtils {
return (*DateUtils)(nil) // the util is stateless, and we do not need to create an instance
}
// AbsoluteShort renders in "Jan 01, 2006" format
func (du *DateUtils) AbsoluteShort(time any) template.HTML {
return dateTimeFormat("short", time)
}
// AbsoluteLong renders in "January 01, 2006" format
func (du *DateUtils) AbsoluteLong(time any) template.HTML {
return dateTimeFormat("long", time)
}
// FullTime renders in "Jan 01, 2006 20:33:44" format
func (du *DateUtils) FullTime(time any) template.HTML {
return dateTimeFormat("full", time)
}
func (du *DateUtils) TimeSince(time any) template.HTML {
return TimeSince(time)
}
// ParseLegacy parses the datetime in legacy format, eg: "2016-01-02" in server's timezone.
// It shouldn't be used in new code. New code should use Time or TimeStamp as much as possible.
func (du *DateUtils) ParseLegacy(datetime string) time.Time {
return parseLegacy(datetime)
}
func parseLegacy(datetime string) time.Time {
t, err := time.Parse(time.RFC3339, datetime)
if err != nil {
t, _ = time.ParseInLocation(time.DateOnly, datetime, setting.DefaultUILocation)
}
return t
}
func dateTimeLegacy(format string, datetime any, _ ...string) template.HTML {
if !setting.IsProd || setting.IsInTesting {
panic("dateTimeLegacy is for backward compatibility only, do not use it in new code")
}
if s, ok := datetime.(string); ok {
datetime = parseLegacy(s)
}
return dateTimeFormat(format, datetime)
}
func timeSinceLegacy(time any, _ translation.Locale) template.HTML {
if !setting.IsProd || setting.IsInTesting {
panic("timeSinceLegacy is for backward compatibility only, do not use it in new code")
}
return TimeSince(time)
}
func anyToTime(any any) (t time.Time, isZero bool) {
switch v := any.(type) {
case nil:
// it is zero
break
case *time.Time:
if v != nil {
t = *v
}
case time.Time:
t = v
case timeutil.TimeStamp:
t = v.AsTime()
case timeutil.TimeStampNano:
t = v.AsTime()
case int:
t = timeutil.TimeStamp(v).AsTime()
case int64:
t = timeutil.TimeStamp(v).AsTime()
default:
panic(fmt.Sprintf("Unsupported time type %T", any))
}
return t, t.IsZero() || t.Unix() == 0
}
func dateTimeFormat(format string, datetime any) template.HTML {
t, isZero := anyToTime(datetime)
if isZero {
return "-"
}
var textEscaped string
datetimeEscaped := html.EscapeString(t.Format(time.RFC3339))
if format == "full" {
textEscaped = html.EscapeString(t.Format("2006-01-02 15:04:05 -07:00"))
} else {
textEscaped = html.EscapeString(t.Format("2006-01-02"))
}
attrs := []string{`weekday=""`, `year="numeric"`}
switch format {
case "short", "long": // date only
attrs = append(attrs, `month="`+format+`"`, `day="numeric"`)
return template.HTML(fmt.Sprintf(`<absolute-date %s date="%s">%s</absolute-date>`, strings.Join(attrs, " "), datetimeEscaped, textEscaped))
case "full": // full date including time
attrs = append(attrs, `format="datetime"`, `month="short"`, `day="numeric"`, `hour="numeric"`, `minute="numeric"`, `second="numeric"`, `data-tooltip-content`, `data-tooltip-interactive="true"`)
return template.HTML(fmt.Sprintf(`<relative-time %s datetime="%s">%s</relative-time>`, strings.Join(attrs, " "), datetimeEscaped, textEscaped))
default:
panic(fmt.Sprintf("Unsupported format %s", format))
}
}
func timeSinceTo(then any, now time.Time) template.HTML {
thenTime, isZero := anyToTime(then)
if isZero {
return "-"
}
friendlyText := thenTime.Format("2006-01-02 15:04:05 -07:00")
// document: https://github.com/github/relative-time-element
attrs := `tense="past"`
isFuture := now.Before(thenTime)
if isFuture {
attrs = `tense="future"`
}
// declare data-tooltip-content attribute to switch from "title" tooltip to "tippy" tooltip
htm := fmt.Sprintf(`<relative-time prefix="" %s datetime="%s" data-tooltip-content data-tooltip-interactive="true">%s</relative-time>`,
attrs, thenTime.Format(time.RFC3339), friendlyText)
return template.HTML(htm)
}
// TimeSince renders relative time HTML given a time
func TimeSince(then any) template.HTML {
return timeSinceTo(then, time.Now())
}