Artifact [8d9ecf55de]

Artifact 8d9ecf55de3f45157645d48e77144982285d115814e9d59fbb65f78e1f328594:

• File repo_merge_renames_test.go — part of check-in [2c3a78cf5e] at 2026-10-22 21:16:18 on branch feat/horizon-cones — fix(merge): follow renames as fossil's merge does

  A file renamed on one side and edited on the other was merged as a deletion plus an addition: the edit was kept under the old name and the renamed copy arrived beside it, so fossil and go-libfossil left different trees and recorded different changes for the same merge.

  Port fossil's rename matching (merge.c merge_cmd): the name pivot nid (pivot_find(1) of M and V, rerun against P when they differ), the renames from nid to V, P and M (path.c find_filename_changes, one way, now path.FilenameChanges), and the fv table those fill (add_renames, the nid!=pid name fill-in, then the files of V, P and M) as merge.MatchFiles/FollowRenames. Checkout.Merge classifies each matched file as before and renames on disk and in vfile a file the merged-in version renamed and the checkout did not, after the other steps, moving swapped names together and setting aside a removed or deleted row that held the new name. Where fossil would rename over a kept tracked file or an untracked one, Merge refuses, as it already does for adds.

  Repo.Merge matches files the same way and commits the merged tree whole, recording the rename (FileToCommit.OldName); the whole-tree commit also stops it carrying forward a file the merge deleted. The CLI prints RENAME lines where fossil's merge prints them. (user: [email protected], size: 3429) [annotate] [blame] [check-ins using] [more...]

package libfossil

import (
	"reflect"
	"testing"
)

// renameMergeRepo commits base, f.txt alone, then feature from it and trunk
// from it with their own files (Files is the whole tree), and merges
// feature into trunk. It returns the merge's files, name to content, and
// the renames its manifest records, new name to old.
func renameMergeRepo(t *testing.T, feature, trunk []FileToCommit) (map[string]string, map[string]string) {
	t.Helper()
	r := newTestRepo(t)
	base := commit(t, r, 0, "base", []FileToCommit{{Name: "f.txt", Content: []byte("1\nx\nx\n2\n")}})
	branchHead := makeBranch(t, r, base, "feature")
	for _, c := range []struct {
		parent int64
		files  []FileToCommit
	}{{branchHead, feature}, {base, trunk}} {
		if _, _, err := r.Commit(CommitOpts{
			ParentID: c.parent, Files: c.files, Comment: "edit", User: "test", PartialManifest: true,
		}); err != nil {
			t.Fatalf("Commit: %v", err)
		}
	}
	rid, _, err := r.Merge("feature", "trunk", "merge", "test")
	if err != nil {
		t.Fatalf("Merge: %v", err)
	}
	files, err := r.ListFiles(rid)
	if err != nil {
		t.Fatal(err)
	}
	got := map[string]string{}
	for _, f := range files {
		got[f.Name] = string(readBlob(t, r, rid, f.Name))
	}
	rows, err := r.DB().Query(`SELECT n.name, p.name FROM mlink
		JOIN filename n ON n.fnid=mlink.fnid JOIN filename p ON p.fnid=mlink.pfnid
		WHERE mid=? AND pfnid>0`, rid)
	if err != nil {
		t.Fatal(err)
	}
	defer rows.Close()
	renames := map[string]string{}
	for rows.Next() {
		var to, from string
		if err := rows.Scan(&to, &from); err != nil {
			t.Fatal(err)
		}
		renames[to] = from
	}
	if err := rows.Err(); err != nil {
		t.Fatal(err)
	}
	return got, renames
}

// Merge follows a rename the merged-in branch made, as fossil's merge does:
// the destination's edit lands under the new name, and the commit records
// the rename.
func TestMerge_FollowsRenameOnSource(t *testing.T) {
	got, renames := renameMergeRepo(t,
		[]FileToCommit{{Name: "r.txt", Content: []byte("1\nx\nx\n2\n"), OldName: "f.txt"}},
		[]FileToCommit{{Name: "f.txt", Content: []byte("1\nx\nx\n2t\n")}})
	if want := map[string]string{"r.txt": "1\nx\nx\n2t\n"}; !reflect.DeepEqual(got, want) {
		t.Errorf("merged files = %q, want %q", got, want)
	}
	if want := map[string]string{"r.txt": "f.txt"}; !reflect.DeepEqual(renames, want) {
		t.Errorf("merge renames = %q, want %q", renames, want)
	}
}

// A file the destination renamed keeps its name and takes the source's
// edit.
func TestMerge_FollowsRenameOnDestination(t *testing.T) {
	got, renames := renameMergeRepo(t,
		[]FileToCommit{{Name: "f.txt", Content: []byte("1f\nx\nx\n2\n")}},
		[]FileToCommit{{Name: "r.txt", Content: []byte("1\nx\nx\n2t\n"), OldName: "f.txt"}})
	if want := map[string]string{"r.txt": "1f\nx\nx\n2t\n"}; !reflect.DeepEqual(got, want) {
		t.Errorf("merged files = %q, want %q", got, want)
	}
	if len(renames) != 0 {
		t.Errorf("merge renames = %q, want none", renames)
	}
}

// A file the source deleted and the destination left alone is gone after
// the merge.
func TestMerge_DropsFileDeletedOnSource(t *testing.T) {
	got, _ := renameMergeRepo(t,
		[]FileToCommit{{Name: "g.txt", Content: []byte("g\n")}},
		[]FileToCommit{{Name: "f.txt", Content: []byte("1\nx\nx\n2\n")}, {Name: "h.txt", Content: []byte("h\n")}})
	if want := map[string]string{"g.txt": "g\n", "h.txt": "h\n"}; !reflect.DeepEqual(got, want) {
		t.Errorf("merged files = %q, want %q", got, want)
	}
}