Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

Fixes #28420

Don't return `nil` if the input was empty.

Part of #27065

This PR touches functions used in templates. As templates are not static
typed, errors are harder to find, but I hope I catch it all. I think
some tests from other persons do not hurt.

To avoid duplicated load of the same data in an HTTP request, we can set
a context cache to do that. i.e. Some pages may load a user from a
database with the same id in different areas on the same page. But the
code is hidden in two different deep logic. How should we share the
user? As a result of this PR, now if both entry functions accept
`context.Context` as the first parameter and we just need to refactor
`GetUserByID` to reuse the user from the context cache. Then it will not
be loaded twice on an HTTP request.

But of course, sometimes we would like to reload an object from the
database, that's why `RemoveContextData` is also exposed.

The core context cache is here. It defines a new context
```go
type cacheContext struct {
	ctx  context.Context
	data map[any]map[any]any
        lock sync.RWMutex
}

var cacheContextKey = struct{}{}

func WithCacheContext(ctx context.Context) context.Context {
	return context.WithValue(ctx, cacheContextKey, &cacheContext{
		ctx:  ctx,
		data: make(map[any]map[any]any),
	})
}
```

Then you can use the below 4 methods to read/write/del the data within
the same context.

```go
func GetContextData(ctx context.Context, tp, key any) any
func SetContextData(ctx context.Context, tp, key, value any)
func RemoveContextData(ctx context.Context, tp, key any)
func GetWithContextCache[T any](ctx context.Context, cacheGroupKey string, cacheTargetID any, f func() (T, error)) (T, error)
```

Then let's take a look at how `system.GetString` implement it.

```go
func GetSetting(ctx context.Context, key string) (string, error) {
	return cache.GetWithContextCache(ctx, contextCacheKey, key, func() (string, error) {
		return cache.GetString(genSettingCacheKey(key), func() (string, error) {
			res, err := GetSettingNoCache(ctx, key)
			if err != nil {
				return "", err
			}
			return res.SettingValue, nil
		})
	})
}
```

First, it will check if context data include the setting object with the
key. If not, it will query from the global cache which may be memory or
a Redis cache. If not, it will get the object from the database. In the
end, if the object gets from the global cache or database, it will be
set into the context cache.

An object stored in the context cache will only be destroyed after the
context disappeared.

Addition to #22256

The `convert` package relies heavily on different models which is
[disallowed by our definition of
modules](https://github.com/go-gitea/gitea/blob/main/CONTRIBUTING.md#design-guideline).
This helps to prevent possible import cycles.

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

Change all license headers to comply with REUSE specification.

Fix #16132

Co-authored-by: flynnnnnnnnnn <flynnnnnnnnnn@github>
Co-authored-by: John Olheiser <john.olheiser@gmail.com>

* Closes #19997

Adds an `updated_at` time field to the `PullReview` API object to
specify when the pull request review's state changed.

Signed-off-by: Yarden Shoham <hrsi88@gmail.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

* Move access and repo permission to models/perm/access

* fix test

* fix git test

* Move functions sequence

* Some improvements per @KN4CK3R and @delvh

* Move issues related code to models/issues

* Move some issues related sub package

* Merge

* Fix test

* Fix test

* Fix test

* Fix test

* Rename some files

* Refactor: teams to api convert

* make org load optional

* more info in tests

This PR continues the work in #17125 by progressively ensuring that git
commands run within the request context.

This now means that the if there is a git repo already open in the context it will be used instead of reopening it.

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Move user related model into models/user

* Fix lint for windows

* Fix windows lint

* Fix windows lint

* Move some tests in models

* Merge

* Expose resolver via API

* [refactor] unify how user data is exported via API

* test time via unix timestamp

The API call: GET /repos/{owner}/{repo}/pulls/{index}/reviews/{id}/comments
returns always the reviewer, but should return the poster.

Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: zeripath <art27@cantab.net>

* Add dismiss review feature

refs:
    https://github.blog/2016-10-12-dismissing-reviews-on-pull-requests/
    https://developer.github.com/v3/pulls/reviews/#dismiss-a-review-for-a-pull-request

* change modal ui and error message

* Add unDismissReview api

Signed-off-by: a101211279 <1012112796@qq.com>
Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: 6543 <6543@obermui.de>

* Add review request api

* add : POST /repos/{owner}/{repo}/pulls/{index}/requested_reviewers
* Remove : DELET /repos/{owner}/{repo}/pulls/{index}/requested_reviewers
* fix some request review bug
* block delet request review by models/DeleteReview()

Signed-off-by: a101211279 <1012112796@qq.com>

* make fmt

* fix bug

* fix test code

* fix typo

* Apply suggestion from code review @jonasfranz

* fix swagger ref

* fix typo

Co-authored-by: Lauris BH <lauris@nix.lv>

* fix comment

* Change response message

* chang response so some simplfy

* Add ErrIllLegalReviewRequest
fix some nits

* make fmt

* Apply suggestions from code review

Co-authored-by: silverwind <me@silverwind.io>

* * Add team support
* fix test
* fix an known bug

* fix nit

* fix test

* Apply suggestions from code review

Co-authored-by: zeripath <art27@cantab.net>

* update get api and add test

Co-authored-by: Lauris BH <lauris@nix.lv>
Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: zeripath <art27@cantab.net>

Fix #11499

Signed-off-by: Andrew Thornton <art27@cantab.net>

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

* API: Added pull review read only endpoints

* Update Structs, move Conversion, Refactor

* refactor

* lint & co

* fix lint + refactor

* add new Review state, rm unessesary, refacotr loadAttributes, convert patch to diff

* add DeletePullReview

* add paggination

* draft1: Create & submit review

* fix lint

* fix lint

* impruve test

* DONT use GhostUser for loadReviewer

* expose comments_count of a PullReview

* infent GetCodeCommentsCount()

* fixes

* fix+impruve

* some nits

* Handle Ghosts :ghost:

* add TEST for GET apis

* complete TESTS

* add HTMLURL to PullReview responce

* code format as per @lafriks

* update swagger definition

* Update routers/api/v1/repo/pull_review.go

Co-authored-by: David Svantesson <davidsvantesson@gmail.com>

* add comments

Co-authored-by: Thomas Berger <loki@lokis-chaos.de>
Co-authored-by: David Svantesson <davidsvantesson@gmail.com>