From 8b08827bdc19412e17edd1fd321c05dc11373f88 Mon Sep 17 00:00:00 2001
From: Alexander Weiss <alex@weissfam.de>
Date: Sun, 4 Jan 2026 23:05:10 +0100
Subject: [PATCH] fix: Use parents instead of parent; allow latest

---
 crates/core/src/commands/backup.rs      | 21 ++++++++++++---------
 crates/core/tests/integration/backup.rs |  2 +-
 2 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/crates/core/src/commands/backup.rs b/crates/core/src/commands/backup.rs
index eb6d31f15..7d2b5ef9d 100644
--- a/crates/core/src/commands/backup.rs
+++ b/crates/core/src/commands/backup.rs
@@ -47,13 +47,13 @@ pub struct ParentOptions {
     #[cfg_attr(feature = "merge", merge(strategy = conflate::option::overwrite_none))]
     pub group_by: Option<SnapshotGroupCriterion>,
 
-    /// Snapshot to use as parent
+    /// Snapshot to use as parent (can be specified multiple times; default: latest)
     #[cfg_attr(
         feature = "clap",
-        clap(long, value_name = "SNAPSHOT", conflicts_with = "force",)
+        clap(long = "parent", value_name = "SNAPSHOT", conflicts_with = "force",)
     )]
     #[cfg_attr(feature = "merge", merge(strategy = conflate::vec::append))]
-    pub parent: Vec<String>,
+    pub parents: Vec<String>,
 
     /// Skip writing of snapshot if nothing changed w.r.t. the parent snapshot.
     #[cfg_attr(feature = "clap", clap(long))]
@@ -99,11 +99,11 @@ impl ParentOptions {
         snap: &SnapshotFile,
         backup_stdin: bool,
     ) -> (Vec<SnapshotId>, Parent) {
+        let group = SnapshotGroup::from_snapshot(snap, self.group_by.unwrap_or_default());
         let parent = if backup_stdin || self.force {
             Vec::new()
-        } else if self.parent.is_empty() {
+        } else if self.parents.is_empty() {
             // get suitable snapshot group from snapshot and opts.group_by. This is used to filter snapshots for the parent detection
-            let group = SnapshotGroup::from_snapshot(snap, self.group_by.unwrap_or_default());
             SnapshotFile::latest(
                 repo.dbe(),
                 |snap| snap.has_group(&group),
@@ -113,10 +113,13 @@ impl ParentOptions {
             .into_iter()
             .collect()
         } else {
-            self.parent
-                .iter()
-                .filter_map(|parent| SnapshotFile::from_id(repo.dbe(), parent).ok())
-                .collect()
+            SnapshotFile::from_strs(
+                repo.dbe(),
+                &self.parents,
+                |snap| snap.has_group(&group),
+                &repo.pb.progress_counter(""),
+            )
+            .unwrap_or_default()
         };
 
         let (parent_trees, parent_ids): (Vec<_>, _) = parent
diff --git a/crates/core/tests/integration/backup.rs b/crates/core/tests/integration/backup.rs
index 5c6b116c7..dbf7673e9 100644
--- a/crates/core/tests/integration/backup.rs
+++ b/crates/core/tests/integration/backup.rs
@@ -88,7 +88,7 @@ fn test_backup_with_tar_gz_passes(
         .tags([StringList::from_str("a,b")?])
         .to_snapshot()?;
     let opts =
-        opts.parent_opts(ParentOptions::default().parent(vec![second_snapshot.id.to_string()]));
+        opts.parent_opts(ParentOptions::default().parents(vec![second_snapshot.id.to_string()]));
     let third_snapshot = repo.backup(&opts, paths, snap)?;
 
     insta_snapshotfile_redaction.bind(|| {