Append to existing trailers in generated squash commit message (#15980)

* Remove superfluous newline before Co-authored-by trailers

* Append to existing PR description trailer section

If the existing PR description message already contains a trailer section (e.g. Signed-off-by: ),
append to it instead of creating a new trailer section.

* Reuse compiled regexp

* Simplify regex and deal with trailing \n in PR description

* Add tests for CommitMessageTrailersPattern

- add support for Key:Value (no space after colon)
- add support for whitespace "folding"

* Update services/pull/pull_test.go

Co-authored-by: Norwin <noerw@users.noreply.github.com>
Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: Norwin <noerw@users.noreply.github.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>

diff --git a/services/pull/pull.go b/services/pull/pull.go
index 7b5dd6a964db85fcb2a8e67498958415ede3b885..db216ddbf4556f69ee3dd0c11a89d025570a7372 100644 (file)
--- a/services/pull/pull.go
+++ b/services/pull/pull.go
@@ -9,6 +9,7 @@ import (
        "bytes"
        "context"
        "fmt"
+       "regexp"
        "strings"
        "time"
 
@@ -528,6 +529,8 @@ func CloseRepoBranchesPulls(doer *models.User, repo *models.Repository) error {
        return nil
 }
 
+var commitMessageTrailersPattern = regexp.MustCompile(`(?:^|\n\n)(?:[\w-]+[ \t]*:[^\n]+\n*(?:[ \t]+[^\n]+\n*)*)+$`)
+
 // GetSquashMergeCommitMessages returns the commit messages between head and merge base (if there is one)
 func GetSquashMergeCommitMessages(pr *models.PullRequest) string {
        if err := pr.LoadIssue(); err != nil {
@@ -583,10 +586,13 @@ func GetSquashMergeCommitMessages(pr *models.PullRequest) string {
        stringBuilder := strings.Builder{}
 
        if !setting.Repository.PullRequest.PopulateSquashCommentWithCommitMessages {
-               stringBuilder.WriteString(pr.Issue.Content)
+               message := strings.TrimSpace(pr.Issue.Content)
+               stringBuilder.WriteString(message)
                if stringBuilder.Len() > 0 {
                        stringBuilder.WriteRune('\n')
-                       stringBuilder.WriteRune('\n')
+                       if !commitMessageTrailersPattern.MatchString(message) {
+                               stringBuilder.WriteRune('\n')
+                       }
                }
        }
 
@@ -657,13 +663,6 @@ func GetSquashMergeCommitMessages(pr *models.PullRequest) string {
                }
        }
 
-       if len(authors) > 0 {
-               if _, err := stringBuilder.WriteRune('\n'); err != nil {
-                       log.Error("Unable to write to string builder Error: %v", err)
-                       return ""
-               }
-       }
-
        for _, author := range authors {
                if _, err := stringBuilder.Write([]byte("Co-authored-by: ")); err != nil {
                        log.Error("Unable to write to string builder Error: %v", err)

diff --git a/services/pull/pull_test.go b/services/pull/pull_test.go
index 64920e355096dafb443c53c5e5b49527092d7369..81627ebb77bcfc7e441e14f41c0c309c63348119 100644 (file)
--- a/services/pull/pull_test.go
+++ b/services/pull/pull_test.go
@@ -5,4 +5,27 @@
 
 package pull
 
+import (
+       "testing"
+
+       "github.com/stretchr/testify/assert"
+)
+
 // TODO TestPullRequest_PushToBaseRepo
+
+func TestPullRequest_CommitMessageTrailersPattern(t *testing.T) {
+       // Not a valid trailer section
+       assert.False(t, commitMessageTrailersPattern.MatchString(""))
+       assert.False(t, commitMessageTrailersPattern.MatchString("No trailer."))
+       assert.False(t, commitMessageTrailersPattern.MatchString("Signed-off-by: Bob <bob@example.com>\nNot a trailer due to following text."))
+       assert.False(t, commitMessageTrailersPattern.MatchString("Message body not correctly separated from trailer section by empty line.\nSigned-off-by: Bob <bob@example.com>"))
+       // Valid trailer section
+       assert.True(t, commitMessageTrailersPattern.MatchString("Signed-off-by: Bob <bob@example.com>"))
+       assert.True(t, commitMessageTrailersPattern.MatchString("Signed-off-by: Bob <bob@example.com>\nOther-Trailer: Value"))
+       assert.True(t, commitMessageTrailersPattern.MatchString("Message body correctly separated from trailer section by empty line.\n\nSigned-off-by: Bob <bob@example.com>"))
+       assert.True(t, commitMessageTrailersPattern.MatchString("Multiple trailers.\n\nSigned-off-by: Bob <bob@example.com>\nOther-Trailer: Value"))
+       assert.True(t, commitMessageTrailersPattern.MatchString("Newline after trailer section.\n\nSigned-off-by: Bob <bob@example.com>\n"))
+       assert.True(t, commitMessageTrailersPattern.MatchString("No space after colon is accepted.\n\nSigned-off-by:Bob <bob@example.com>"))
+       assert.True(t, commitMessageTrailersPattern.MatchString("Additional whitespace is accepted.\n\nSigned-off-by \t :  \tBob   <bob@example.com>   "))
+       assert.True(t, commitMessageTrailersPattern.MatchString("Folded value.\n\nFolded-trailer: This is\n a folded\n   trailer value\nOther-Trailer: Value"))
+}