fix(DS-REL): date a re-added section from its last addition (v0.3.2)

README.md

@@ -65,7 +65,9 @@ Exit codes: 0 when the documents agree with the code, 1 with findings; see
 
 The checks that need tags and history (DS-SEC's supported minor, DS-REL's untagged
 section) run only in a git work tree with its tags: check out with
-`fetch-depth: 0` in CI.
+`fetch-depth: 0` in CI. DS-REL dates the newest section from the last commit
+that added its heading: a section that was folded away and written again dates
+from the new commit, and one not committed yet has no date.
 
 Documents of history and plans are not checked: `RELEASE.md` (apart from
 DS-REL), `CHANGELOG.md`, `PLAN.md`, `ROADMAP.md`, `PROGRESS.md`, ADRs,

RELEASE.md

@@ -1,5 +1,16 @@
 # docsync Releases
 
+## v0.3.2
+
+**Date:** 2026-11-14
+**Previous release:** v0.3.1
+
+### Fixed
+
+- DS-REL dates an untagged newest section from the last commit that added its heading, not the first. A heading that was added, folded into another section and written again (go-iec61850's `## v1.21.0`) is no longer reported as days old in the pull request that writes it again. A heading that is back in the work tree but not committed has no date, as one never committed has none.
+
+---
+
 ## v0.3.1
 
 **Date:** 2026-11-07

internal/gitinfo/added_test.go

@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: MIT
+
+package gitinfo
+
+import (
+	"os"
+	"os/exec"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+// TestAdded dates a heading from the commit that added it as it is now: a
+// heading that was added, removed and added again dates from the last
+// addition, and one that is back but not committed has no date.
+func TestAdded(t *testing.T) {
+	if _, err := exec.LookPath("git"); err != nil {
+		t.Skip("no git")
+	}
+	top := t.TempDir()
+	// The checked directory is a nested module, as in a CLI under cmd/.
+	dir := filepath.Join(top, "cmd", "tool")
+	if err := os.MkdirAll(dir, 0o755); err != nil {
+		t.Fatal(err)
+	}
+	git := func(date string, args ...string) {
+		t.Helper()
+		cmd := exec.Command("git", args...)
+		cmd.Dir = top
+		cmd.Env = append(os.Environ(), "GIT_AUTHOR_NAME=t", "GIT_AUTHOR_EMAIL=t@example.com", "GIT_COMMITTER_NAME=t",
+			"GIT_COMMITTER_EMAIL=t@example.com", "GIT_AUTHOR_DATE="+date, "GIT_COMMITTER_DATE="+date)
+		if out, err := cmd.CombinedOutput(); err != nil {
+			t.Fatalf("git %v: %v %s", args, err, out)
+		}
+	}
+	write := func(body string) {
+		t.Helper()
+		if err := os.WriteFile(filepath.Join(dir, "RELEASE.md"), []byte(body), 0o644); err != nil {
+			t.Fatal(err)
+		}
+	}
+	commit := func(date, msg string) {
+		t.Helper()
+		git(date, "add", ".")
+		git(date, "commit", "-qm", msg)
+	}
+	const head = "## v1.1.0"
+	git("2026-01-01T00:00:00Z", "init", "-q")
+	write("# Releases\n\n## v1.0.0\n\n- First.\n")
+	commit("2026-01-01T00:00:00Z", "v1.0.0")
+	r := Open(dir)
+	if _, ok := r.Added("RELEASE.md", head); ok {
+		t.Fatal("never added: no date")
+	}
+
+	write("# Releases\n\n## v1.1.0\n\n- Second.\n\n## v1.0.0\n\n- First.\n")
+	commit("2026-01-02T00:00:00Z", "add v1.1.0")
+	want := time.Date(2026, 1, 2, 0, 0, 0, 0, time.UTC)
+	if at, ok := r.Added("RELEASE.md", head); !ok || !at.Equal(want) {
+		t.Fatalf("added once: %v %v, want %v", at, ok, want)
+	}
+
+	// Folded away, then back without a commit.
+	write("# Releases\n\n## v1.0.0\n\n- First.\n")
+	commit("2026-01-03T00:00:00Z", "fold v1.1.0")
+	write("# Releases\n\n## v1.1.0\n\n- Third.\n\n## v1.0.0\n\n- First.\n")
+	if at, ok := r.Added("RELEASE.md", head); ok {
+		t.Fatalf("back but not committed: %v, want no date", at)
+	}
+
+	commit("2026-01-09T00:00:00Z", "add v1.1.0 again")
+	want = time.Date(2026, 1, 9, 0, 0, 0, 0, time.UTC)
+	if at, ok := r.Added("RELEASE.md", head); !ok || !at.Equal(want) {
+		t.Fatalf("added again: %v %v, want %v (the last addition, not the first)", at, ok, want)
+	}
+
+	// An edit that keeps the heading does not move its date.
+	write("# Releases\n\n## v1.1.0\n\n- Third, reworded.\n\n## v1.0.0\n\n- First.\n")
+	commit("2026-01-10T00:00:00Z", "reword")
+	if at, ok := r.Added("RELEASE.md", head); !ok || !at.Equal(want) {
+		t.Fatalf("after an edit: %v %v, want %v", at, ok, want)
+	}
+}

internal/gitinfo/gitinfo.go

@@ -59,24 +59,33 @@ func (r *Repo) Latest() (Version, bool) {
 // HasTag reports whether v is tagged.
 func (r *Repo) HasTag(v Version) bool { return slices.Contains(r.Tags(), v) }
 
-// Added returns the time of the oldest commit that added s to file, and
-// false when no commit did (s is not committed yet).
+// Added returns the time of the commit that added s to file as it is now:
+// the newest commit that changed how often s occurs in file, when file holds
+// s at that commit. A string that was added, removed and added again dates
+// from the last addition. file is relative to the repository's directory.
+// Added returns false when no commit added s, or when the newest such commit
+// removed it (s is back in the work tree but not committed yet).
 func (r *Repo) Added(file, s string) (time.Time, bool) {
 	if r == nil {
 		return time.Time{}, false
 	}
-	out, err := exec.Command("git", "-C", r.Dir, "log", "--format=%ct", "-S"+s, "--", file).Output()
+	out, err := exec.Command("git", "-C", r.Dir, "log", "-1", "--format=%H %ct", "-S"+s, "--", file).Output()
 	if err != nil {
 		return time.Time{}, false
 	}
 	f := strings.Fields(string(out))
-	if len(f) == 0 {
+	if len(f) != 2 {
 		return time.Time{}, false
 	}
-	sec, err := strconv.ParseInt(f[len(f)-1], 10, 64)
+	sec, err := strconv.ParseInt(f[1], 10, 64)
 	if err != nil {
 		return time.Time{}, false
 	}
+	// "./" makes the path relative to r.Dir, not to the top of the work tree.
+	blob, err := exec.Command("git", "-C", r.Dir, "show", f[0]+":./"+file).Output()
+	if err != nil || !strings.Contains(string(blob), s) {
+		return time.Time{}, false
+	}
 	return time.Unix(sec, 0), true
 }