1 files changed, 171 insertions, 0 deletions
diff --git a/services/pull/commit_status.go b/services/pull/commit_status.go
new file mode 100644
index 0000000..0d4763a
--- /dev/null
+++ b/services/pull/commit_status.go
@@ -0,0 +1,171 @@
+// Copyright 2019 The Gitea Authors.
+// All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package pull
+
+import (
+	"context"
+	"errors"
+	"fmt"
+
+	"code.gitea.io/gitea/models/db"
+	git_model "code.gitea.io/gitea/models/git"
+	issues_model "code.gitea.io/gitea/models/issues"
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/gitrepo"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/structs"
+
+	"github.com/gobwas/glob"
+)
+
+// MergeRequiredContextsCommitStatus returns a commit status state for given required contexts
+func MergeRequiredContextsCommitStatus(commitStatuses []*git_model.CommitStatus, requiredContexts []string) structs.CommitStatusState {
+	// matchedCount is the number of `CommitStatus.Context` that match any context of `requiredContexts`
+	matchedCount := 0
+	returnedStatus := structs.CommitStatusSuccess
+
+	if len(requiredContexts) > 0 {
+		requiredContextsGlob := make(map[string]glob.Glob, len(requiredContexts))
+		for _, ctx := range requiredContexts {
+			if gp, err := glob.Compile(ctx); err != nil {
+				log.Error("glob.Compile %s failed. Error: %v", ctx, err)
+			} else {
+				requiredContextsGlob[ctx] = gp
+			}
+		}
+
+		for _, gp := range requiredContextsGlob {
+			var targetStatus structs.CommitStatusState
+			for _, commitStatus := range commitStatuses {
+				if gp.Match(commitStatus.Context) {
+					targetStatus = commitStatus.State
+					matchedCount++
+					break
+				}
+			}
+
+			// If required rule not match any action, then it is pending
+			if targetStatus == "" {
+				if structs.CommitStatusPending.NoBetterThan(returnedStatus) {
+					returnedStatus = structs.CommitStatusPending
+				}
+				break
+			}
+
+			if targetStatus.NoBetterThan(returnedStatus) {
+				returnedStatus = targetStatus
+			}
+		}
+	}
+
+	if matchedCount == 0 && returnedStatus == structs.CommitStatusSuccess {
+		status := git_model.CalcCommitStatus(commitStatuses)
+		if status != nil {
+			return status.State
+		}
+		return ""
+	}
+
+	return returnedStatus
+}
+
+// IsCommitStatusContextSuccess returns true if all required status check contexts succeed.
+func IsCommitStatusContextSuccess(commitStatuses []*git_model.CommitStatus, requiredContexts []string) bool {
+	// If no specific context is required, require that last commit status is a success
+	if len(requiredContexts) == 0 {
+		status := git_model.CalcCommitStatus(commitStatuses)
+		if status == nil || status.State != structs.CommitStatusSuccess {
+			return false
+		}
+		return true
+	}
+
+	for _, ctx := range requiredContexts {
+		var found bool
+		for _, commitStatus := range commitStatuses {
+			if commitStatus.Context == ctx {
+				if commitStatus.State != structs.CommitStatusSuccess {
+					return false
+				}
+
+				found = true
+				break
+			}
+		}
+		if !found {
+			return false
+		}
+	}
+	return true
+}
+
+// IsPullCommitStatusPass returns if all required status checks PASS
+func IsPullCommitStatusPass(ctx context.Context, pr *issues_model.PullRequest) (bool, error) {
+	pb, err := git_model.GetFirstMatchProtectedBranchRule(ctx, pr.BaseRepoID, pr.BaseBranch)
+	if err != nil {
+		return false, fmt.Errorf("GetFirstMatchProtectedBranchRule: %w", err)
+	}
+	if pb == nil || !pb.EnableStatusCheck {
+		return true, nil
+	}
+
+	state, err := GetPullRequestCommitStatusState(ctx, pr)
+	if err != nil {
+		return false, err
+	}
+	return state.IsSuccess(), nil
+}
+
+// GetPullRequestCommitStatusState returns pull request merged commit status state
+func GetPullRequestCommitStatusState(ctx context.Context, pr *issues_model.PullRequest) (structs.CommitStatusState, error) {
+	// Ensure HeadRepo is loaded
+	if err := pr.LoadHeadRepo(ctx); err != nil {
+		return "", fmt.Errorf("LoadHeadRepo: %w", err)
+	}
+
+	// check if all required status checks are successful
+	headGitRepo, closer, err := gitrepo.RepositoryFromContextOrOpen(ctx, pr.HeadRepo)
+	if err != nil {
+		return "", fmt.Errorf("RepositoryFromContextOrOpen: %w", err)
+	}
+	defer closer.Close()
+
+	if pr.Flow == issues_model.PullRequestFlowGithub && !headGitRepo.IsBranchExist(pr.HeadBranch) {
+		return "", errors.New("head branch does not exist, can not merge")
+	}
+	if pr.Flow == issues_model.PullRequestFlowAGit && !git.IsReferenceExist(ctx, headGitRepo.Path, pr.GetGitRefName()) {
+		return "", errors.New("head branch does not exist, can not merge")
+	}
+
+	var sha string
+	if pr.Flow == issues_model.PullRequestFlowGithub {
+		sha, err = headGitRepo.GetBranchCommitID(pr.HeadBranch)
+	} else {
+		sha, err = headGitRepo.GetRefCommitID(pr.GetGitRefName())
+	}
+	if err != nil {
+		return "", err
+	}
+
+	if err := pr.LoadBaseRepo(ctx); err != nil {
+		return "", fmt.Errorf("LoadBaseRepo: %w", err)
+	}
+
+	commitStatuses, _, err := git_model.GetLatestCommitStatus(ctx, pr.BaseRepo.ID, sha, db.ListOptionsAll)
+	if err != nil {
+		return "", fmt.Errorf("GetLatestCommitStatus: %w", err)
+	}
+
+	pb, err := git_model.GetFirstMatchProtectedBranchRule(ctx, pr.BaseRepoID, pr.BaseBranch)
+	if err != nil {
+		return "", fmt.Errorf("GetFirstMatchProtectedBranchRule: %w", err)
+	}
+	var requiredContexts []string
+	if pb != nil {
+		requiredContexts = pb.StatusCheckContexts
+	}
+
+	return MergeRequiredContextsCommitStatus(commitStatuses, requiredContexts), nil
+}