ci: Allow release note enrichment when "closes" is present (#5398)

An interesting thing I discovered with release please is that if a
commit has a reference to a closed issue, this will be called out in the
changelog 🎉

For example:

```
* Invalid handling of id in foreach when using discovery components (\#5322) (61fe184), closes \#5297
```

The only problem is this breaks the way I wrote the regex for the
release not enrichment script. This PR fixes that.

Author: jharvey10

tools/release/enrich-release-notes/main.go

@@ -13,6 +13,10 @@ import (
 	"github.com/grafana/alloy/tools/release/internal/version"
 )
 
+// commitPattern matches a commit SHA in markdown link format: "([abc1234](https://github.com/.../commit/...))"
+// It captures the short SHA from the link text, regardless of surrounding context.
+var commitPattern = regexp.MustCompile(`\(\[([a-f0-9]{7,40})\]\(https://github\.com/[^)]+\)\)`)
+
 // commitAuthorsQuery is the GraphQL query to fetch all authors for a commit.
 const commitAuthorsQuery = `query($owner: String!, $repo: String!, $oid: GitObjectID!) {
 	repository(owner: $owner, name: $repo) {
@@ -109,13 +113,20 @@ func main() {
 	fmt.Println("✅ Release notes updated successfully")
 }
 
+// extractCommitSHA extracts a commit SHA from a changelog line.
+// Returns the SHA if found, or an empty string if no commit link is present.
+func extractCommitSHA(line string) string {
+	matches := commitPattern.FindStringSubmatch(line)
+	if matches == nil {
+		return ""
+	}
+	return matches[1]
+}
+
 // addContributorInfo adds contributor usernames to changelog entries.
 // It extracts commit SHAs from each line and looks up the author + co-authors.
 func addContributorInfo(ctx context.Context, client *gh.Client, body string) string {
 	lines := strings.Split(body, "\n")
-	// Match commit SHA in markdown link format: "([abc1234](https://github.com/.../commit/...))"
-	// This captures the short SHA from the link text
-	commitPattern := regexp.MustCompile(`\(\[([a-f0-9]{7,40})\]\(https://github\.com/[^)]+\)\)\s*$`)
 
 	for i, line := range lines {
 		if strings.TrimSpace(line) == "" {
@@ -124,12 +135,11 @@ func addContributorInfo(ctx context.Context, client *gh.Client, body string) str
 
 		fmt.Printf("   Processing line %d: %s\n", i, line)
 
-		matches := commitPattern.FindStringSubmatch(line)
-		if matches == nil {
+		sha := extractCommitSHA(line)
+		if sha == "" {
 			fmt.Printf("   No commit SHA found in line %d\n", i)
 			continue
 		}
-		sha := matches[1]
 
 		contributors, err := getCommitContributors(ctx, client, sha)
 		if err != nil {

tools/release/enrich-release-notes/main_test.go

@@ -0,0 +1,120 @@
+package main
+
+import "testing"
+
+func TestExtractCommitSHA(t *testing.T) {
+	tests := []struct {
+		name        string
+		input       string
+		expectedSHA string
+	}{
+		{
+			name:        "commit link at end of line",
+			input:       "* HTTP/2 is no longer always disabled in loki.write ([#5267](https://github.com/grafana/alloy/issues/5267)) ([1c97c2d](https://github.com/grafana/alloy/commit/1c97c2d569fcda2f6761534150b063d1404dc388))",
+			expectedSHA: "1c97c2d",
+		},
+		{
+			name:        "commit link with closes reference after",
+			input:       "* Invalid handling of `id` in `foreach` when using discovery components ([#5322](https://github.com/grafana/alloy/issues/5322)) ([61fe184](https://github.com/grafana/alloy/commit/61fe1845d3b109992cbb0ec99a062ac113c1a411)), closes [#5297](https://github.com/grafana/alloy/issues/5297)",
+			expectedSHA: "61fe184",
+		},
+		{
+			name:        "commit link with extra notes after",
+			input:       "* Some fix ([deadbeef](https://github.com/grafana/alloy/commit/deadbeef)) - extra notes here",
+			expectedSHA: "deadbeef",
+		},
+		{
+			name:        "full 40-character SHA",
+			input:       "* Fix bug ([abc1234567890def1234567890abc1234567890](https://github.com/grafana/alloy/commit/abc1234567890def1234567890abc1234567890))",
+			expectedSHA: "abc1234567890def1234567890abc1234567890",
+		},
+		{
+			name:        "no parens around link",
+			input:       "* No parens [abc1234](https://github.com/grafana/alloy/commit/abc1234)",
+			expectedSHA: "",
+		},
+		{
+			name:        "just a PR reference",
+			input:       "* Just a PR reference (#1234)",
+			expectedSHA: "",
+		},
+		{
+			name:        "empty line",
+			input:       "",
+			expectedSHA: "",
+		},
+		{
+			name:        "line with no commit info",
+			input:       "### Bug Fixes",
+			expectedSHA: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			sha := extractCommitSHA(tt.input)
+			if sha != tt.expectedSHA {
+				t.Errorf("extractCommitSHA(%q) = %q, want %q", tt.input, sha, tt.expectedSHA)
+			}
+		})
+	}
+}
+
+func TestFormatAttribution(t *testing.T) {
+	tests := []struct {
+		name      string
+		usernames []string
+		expected  string
+	}{
+		{
+			name:      "single user",
+			usernames: []string{"alice"},
+			expected:  "(@alice)",
+		},
+		{
+			name:      "multiple users",
+			usernames: []string{"alice", "bob", "charlie"},
+			expected:  "(@alice, @bob, @charlie)",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := formatAttribution(tt.usernames)
+			if result != tt.expected {
+				t.Errorf("formatAttribution(%v) = %q, want %q", tt.usernames, result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestDeriveDocTag(t *testing.T) {
+	tests := []struct {
+		name     string
+		tag      string
+		expected string
+	}{
+		{
+			name:     "standard release",
+			tag:      "v1.15.2",
+			expected: "v1.15",
+		},
+		{
+			name:     "release candidate",
+			tag:      "v1.2.3-rc.0",
+			expected: "v1.2",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result, err := deriveDocTag(tt.tag)
+			if err != nil {
+				t.Fatalf("deriveDocTag(%q) returned error: %v", tt.tag, err)
+			}
+			if result != tt.expected {
+				t.Errorf("deriveDocTag(%q) = %q, want %q", tt.tag, result, tt.expected)
+			}
+		})
+	}
+}