Add the ability to pin Issues (#24406)

This adds the ability to pin important Issues and Pull Requests. You can
also move pinned Issues around to change their Position. Resolves #2175.

## Screenshots

![grafik](https://user-images.githubusercontent.com/15185051/235123207-0aa39869-bb48-45c3-abe2-ba1e836046ec.png)

![grafik](https://user-images.githubusercontent.com/15185051/235123297-152a16ea-a857-451d-9a42-61f2cd54dd75.png)

![grafik](https://user-images.githubusercontent.com/15185051/235640782-cbfe25ec-6254-479a-a3de-133e585d7a2d.png)

The Design was mostly copied from the Projects Board.

## Implementation
This uses a new `pin_order` Column in the `issue` table. If the value is
set to 0, the Issue is not pinned. If it's set to a bigger value, the
value is the Position. 1 means it's the first pinned Issue, 2 means it's
the second one etc. This is dived into Issues and Pull requests for each
Repo.

## TODO
- [x] You can currently pin as many Issues as you want. Maybe we should
add a Limit, which is configurable. GitHub uses 3, but I prefer 6, as
this is better for bigger Projects, but I'm open for suggestions.
- [x] Pin and Unpin events need to be added to the Issue history.
- [x] Tests
- [x] Migration

**The feature itself is currently fully working, so tester who may find
weird edge cases are very welcome!**

---------

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

1 files changed, 205 insertions, 0 deletions

diff --git a/tests/integration/api_issue_pin_test.go b/tests/integration/api_issue_pin_test.go
new file mode 100644
index 0000000000..65be1d74f2
--- /dev/null
+++ b/tests/integration/api_issue_pin_test.go
@@ -0,0 +1,205 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package integration
+
+import (
+	"fmt"
+	"net/http"
+	"testing"
+
+	auth_model "code.gitea.io/gitea/models/auth"
+	issues_model "code.gitea.io/gitea/models/issues"
+	repo_model "code.gitea.io/gitea/models/repo"
+	"code.gitea.io/gitea/models/unittest"
+	user_model "code.gitea.io/gitea/models/user"
+	api "code.gitea.io/gitea/modules/structs"
+	"code.gitea.io/gitea/tests"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestAPIPinIssue(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	assert.NoError(t, unittest.LoadFixtures())
+
+	repo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+	issue := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{RepoID: repo.ID})
+	owner := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: repo.OwnerID})
+
+	session := loginUser(t, owner.Name)
+	token := getTokenForLoggedInUser(t, session, auth_model.AccessTokenScopeRepo)
+
+	// Pin the Issue
+	urlStr := fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d/pin?token=%s",
+		repo.OwnerName, repo.Name, issue.Index, token)
+	req := NewRequest(t, "POST", urlStr)
+	MakeRequest(t, req, http.StatusNoContent)
+
+	// Check if the Issue is pinned
+	urlStr = fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d", repo.OwnerName, repo.Name, issue.Index)
+	req = NewRequest(t, "GET", urlStr)
+	resp := MakeRequest(t, req, http.StatusOK)
+	var issueAPI api.Issue
+	DecodeJSON(t, resp, &issueAPI)
+	assert.Equal(t, 1, issueAPI.PinOrder)
+}
+
+func TestAPIUnpinIssue(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	assert.NoError(t, unittest.LoadFixtures())
+
+	repo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+	issue := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{RepoID: repo.ID})
+	owner := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: repo.OwnerID})
+
+	session := loginUser(t, owner.Name)
+	token := getTokenForLoggedInUser(t, session, auth_model.AccessTokenScopeRepo)
+
+	// Pin the Issue
+	urlStr := fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d/pin?token=%s",
+		repo.OwnerName, repo.Name, issue.Index, token)
+	req := NewRequest(t, "POST", urlStr)
+	MakeRequest(t, req, http.StatusNoContent)
+
+	// Check if the Issue is pinned
+	urlStr = fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d", repo.OwnerName, repo.Name, issue.Index)
+	req = NewRequest(t, "GET", urlStr)
+	resp := MakeRequest(t, req, http.StatusOK)
+	var issueAPI api.Issue
+	DecodeJSON(t, resp, &issueAPI)
+	assert.Equal(t, 1, issueAPI.PinOrder)
+
+	// Unpin the Issue
+	urlStr = fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d/pin?token=%s",
+		repo.OwnerName, repo.Name, issue.Index, token)
+	req = NewRequest(t, "DELETE", urlStr)
+	MakeRequest(t, req, http.StatusNoContent)
+
+	// Check if the Issue is no longer pinned
+	urlStr = fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d", repo.OwnerName, repo.Name, issue.Index)
+	req = NewRequest(t, "GET", urlStr)
+	resp = MakeRequest(t, req, http.StatusOK)
+	DecodeJSON(t, resp, &issueAPI)
+	assert.Equal(t, 0, issueAPI.PinOrder)
+}
+
+func TestAPIMoveIssuePin(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	assert.NoError(t, unittest.LoadFixtures())
+
+	repo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+	issue := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{RepoID: repo.ID})
+	issue2 := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{ID: 2, RepoID: repo.ID})
+	owner := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: repo.OwnerID})
+
+	session := loginUser(t, owner.Name)
+	token := getTokenForLoggedInUser(t, session, auth_model.AccessTokenScopeRepo)
+
+	// Pin the first Issue
+	urlStr := fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d/pin?token=%s",
+		repo.OwnerName, repo.Name, issue.Index, token)
+	req := NewRequest(t, "POST", urlStr)
+	MakeRequest(t, req, http.StatusNoContent)
+
+	// Check if the first Issue is pinned at position 1
+	urlStr = fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d", repo.OwnerName, repo.Name, issue.Index)
+	req = NewRequest(t, "GET", urlStr)
+	resp := MakeRequest(t, req, http.StatusOK)
+	var issueAPI api.Issue
+	DecodeJSON(t, resp, &issueAPI)
+	assert.Equal(t, 1, issueAPI.PinOrder)
+
+	// Pin the second Issue
+	urlStr = fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d/pin?token=%s",
+		repo.OwnerName, repo.Name, issue2.Index, token)
+	req = NewRequest(t, "POST", urlStr)
+	MakeRequest(t, req, http.StatusNoContent)
+
+	// Move the first Issue to position 2
+	urlStr = fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d/pin/2?token=%s",
+		repo.OwnerName, repo.Name, issue.Index, token)
+	req = NewRequest(t, "PATCH", urlStr)
+	MakeRequest(t, req, http.StatusNoContent)
+
+	// Check if the first Issue is pinned at position 2
+	urlStr = fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d", repo.OwnerName, repo.Name, issue.Index)
+	req = NewRequest(t, "GET", urlStr)
+	resp = MakeRequest(t, req, http.StatusOK)
+	var issueAPI3 api.Issue
+	DecodeJSON(t, resp, &issueAPI3)
+	assert.Equal(t, 2, issueAPI3.PinOrder)
+
+	// Check if the second Issue is pinned at position 1
+	urlStr = fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d", repo.OwnerName, repo.Name, issue2.Index)
+	req = NewRequest(t, "GET", urlStr)
+	resp = MakeRequest(t, req, http.StatusOK)
+	var issueAPI4 api.Issue
+	DecodeJSON(t, resp, &issueAPI4)
+	assert.Equal(t, 1, issueAPI4.PinOrder)
+}
+
+func TestAPIListPinnedIssues(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	assert.NoError(t, unittest.LoadFixtures())
+
+	repo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+	issue := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{RepoID: repo.ID})
+	owner := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: repo.OwnerID})
+
+	session := loginUser(t, owner.Name)
+	token := getTokenForLoggedInUser(t, session, auth_model.AccessTokenScopeRepo)
+
+	// Pin the Issue
+	urlStr := fmt.Sprintf("/api/v1/repos/%s/%s/issues/%d/pin?token=%s",
+		repo.OwnerName, repo.Name, issue.Index, token)
+	req := NewRequest(t, "POST", urlStr)
+	MakeRequest(t, req, http.StatusNoContent)
+
+	// Check if the Issue is in the List
+	urlStr = fmt.Sprintf("/api/v1/repos/%s/%s/issues/pinned", repo.OwnerName, repo.Name)
+	req = NewRequest(t, "GET", urlStr)
+	resp := MakeRequest(t, req, http.StatusOK)
+	var issueList []api.Issue
+	DecodeJSON(t, resp, &issueList)
+
+	assert.Equal(t, 1, len(issueList))
+	assert.Equal(t, issue.ID, issueList[0].ID)
+}
+
+func TestAPIListPinnedPullrequests(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	assert.NoError(t, unittest.LoadFixtures())
+
+	repo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+
+	urlStr := fmt.Sprintf("/api/v1/repos/%s/%s/pulls/pinned", repo.OwnerName, repo.Name)
+	req := NewRequest(t, "GET", urlStr)
+	resp := MakeRequest(t, req, http.StatusOK)
+	var prList []api.PullRequest
+	DecodeJSON(t, resp, &prList)
+
+	assert.Equal(t, 0, len(prList))
+}
+
+func TestAPINewPinAllowed(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	repo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+	owner := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: repo.OwnerID})
+
+	urlStr := fmt.Sprintf("/api/v1/repos/%s/%s/new_pin_allowed", owner.Name, repo.Name)
+	req := NewRequest(t, "GET", urlStr)
+	resp := MakeRequest(t, req, http.StatusOK)
+
+	var newPinsAllowed api.NewIssuePinsAllowed
+	DecodeJSON(t, resp, &newPinsAllowed)
+
+	assert.True(t, newPinsAllowed.Issues)
+	assert.True(t, newPinsAllowed.PullRequests)
+}