cmd: Add -r argument to jj restore

It now behaves similarly to `jj diffedit`, `jj diff`, etc.

CHANGELOG.md

@@ -13,8 +13,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 * `jj git push --deleted` will remove all locally deleted branches from the remote.
 
-* `jj restore` without `--from` works correctly even if `@` is a merge
-  commit.
+* `jj restore`  now works correctly without `--from` works correctly even if `@`
+  is a merge commit. It gained a `-r` argument and its interface is now in line
+  with `jj diff`, `jj diffedit`, etc.
 
 * `jj rebase` now accepts multiple `-s` and `-b` arguments. Revsets with
   multiple commits are allowed with `--allow-large-revsets`.

src/commands/mod.rs

@@ -582,18 +582,28 @@ struct ResolveArgs {
 
 /// Restore paths from another revision
 ///
+/// With the `-r` option, which is the default, restores a revision from its
+/// parent (or the merge of its parents).
+///
+/// If `--to` and/or `--from` are specified, restores one revision from the
+/// content of another revision.
+///
 /// That means that the paths get the same content in the destination (`--to`)
 /// as they had in the source (`--from`). This is typically used for undoing
 /// changes to some paths in the working copy (`jj restore <paths>`).
 ///
-/// When neither `--from` nor `--to` is specified, the command restores into the
-/// working copy from its parent. If one of `--from` or `--to` is specified, the
-/// other one defaults to the working copy.
+/// If one of `--from` or `--to` is specified, the other one defaults to the
+/// working copy.
 ///
 /// See `jj diffedit` if you'd like to restore portions of files rather than
 /// entire files.
 #[derive(clap::Args, Clone, Debug)]
 struct RestoreArgs {
+    /// The revision to restore. Defaults to @ if neither --to nor --from are
+    /// specified.
+    #[arg(long, short, conflicts_with_all=["to", "from"])]
+    revision: Option<RevisionArg>,
+
     /// Revision to restore from (source)
     #[arg(long)]
     from: Option<RevisionArg>,
@@ -623,7 +633,7 @@ struct RestoreArgs {
 /// changes into or out of the parent revision.
 #[derive(clap::Args, Clone, Debug)]
 struct DiffeditArgs {
-    /// The revision to touch up. Defaults to @ if --to/--from are not
+    /// The revision to touch up. Defaults to @ if neither --to nor --from are
     /// specified.
     #[arg(long, short)]
     revision: Option<RevisionArg>,
@@ -2509,7 +2519,8 @@ fn cmd_restore(
             .resolve_single_rev(args.from.as_deref().unwrap_or("@"))?
             .tree();
     } else {
-        to_commit = workspace_command.resolve_single_rev("@")?;
+        to_commit =
+            workspace_command.resolve_single_rev(args.revision.as_deref().unwrap_or("@"))?;
         from_tree = merge_commit_trees(workspace_command.repo(), &to_commit.parents());
     }
     workspace_command.check_rewritable(&to_commit)?;

tests/test_restore_command.rs

@@ -42,12 +42,34 @@ fn test_restore() {
     let stdout = test_env.jj_cmd_success(&repo_path, &["diff", "-s"]);
     insta::assert_snapshot!(stdout, @"");
 
-    // Can restore from other revision
+    // Can restore another revision
+    test_env.jj_cmd_success(&repo_path, &["undo"]);
+    let stdout = test_env.jj_cmd_success(&repo_path, &["diff", "-s", "-r=@-"]);
+    insta::assert_snapshot!(stdout, @r###"
+    A file2
+    "###);
+    let stdout = test_env.jj_cmd_success(&repo_path, &["restore", "-r=@-"]);
+    insta::assert_snapshot!(stdout, @r###"
+    Created e989e4b86680 (no description set)
+    Rebased 1 descendant commits
+    Working copy now at: b47256590e11 (no description set)
+    Added 0 files, modified 1 files, removed 0 files
+    "###);
+    let stdout = test_env.jj_cmd_success(&repo_path, &["diff", "-s", "-r=@-"]);
+    insta::assert_snapshot!(stdout, @"");
+
+    // Cannot restore the root revision
+    let stderr = test_env.jj_cmd_failure(&repo_path, &["restore", "-r=root"]);
+    insta::assert_snapshot!(stderr, @r###"
+    Error: Cannot rewrite the root commit
+    "###);
+
+    // Can restore this revision from another revision
     test_env.jj_cmd_success(&repo_path, &["undo"]);
     let stdout = test_env.jj_cmd_success(&repo_path, &["restore", "--from", "@--"]);
     insta::assert_snapshot!(stdout, @r###"
-    Created 9cb58509136b (no description set)
-    Working copy now at: 9cb58509136b (no description set)
+    Created 1dd6eb63d587 (no description set)
+    Working copy now at: 1dd6eb63d587 (no description set)
     Added 1 files, modified 0 files, removed 2 files
     "###);
     let stdout = test_env.jj_cmd_success(&repo_path, &["diff", "-s"]);
@@ -59,9 +81,9 @@ fn test_restore() {
     test_env.jj_cmd_success(&repo_path, &["undo"]);
     let stdout = test_env.jj_cmd_success(&repo_path, &["restore", "--to", "@-"]);
     insta::assert_snapshot!(stdout, @r###"
-    Created 5ed06151e039 (no description set)
+    Created ec9d5b59c3cf (no description set)
     Rebased 1 descendant commits
-    Working copy now at: ca6c95b68bd2 (no description set)
+    Working copy now at: d6f3c6815772 (no description set)
     "###);
     let stdout = test_env.jj_cmd_success(&repo_path, &["diff", "-s"]);
     insta::assert_snapshot!(stdout, @"");
@@ -76,9 +98,9 @@ fn test_restore() {
     test_env.jj_cmd_success(&repo_path, &["undo"]);
     let stdout = test_env.jj_cmd_success(&repo_path, &["restore", "--from", "@", "--to", "@-"]);
     insta::assert_snapshot!(stdout, @r###"
-    Created c83e17dc46fd (no description set)
+    Created 5f6eb3d5c5bf (no description set)
     Rebased 1 descendant commits
-    Working copy now at: df9fb6892f99 (no description set)
+    Working copy now at: 525afd5d4a26 (no description set)
     "###);
     let stdout = test_env.jj_cmd_success(&repo_path, &["diff", "-s"]);
     insta::assert_snapshot!(stdout, @"");
@@ -93,8 +115,8 @@ fn test_restore() {
     test_env.jj_cmd_success(&repo_path, &["undo"]);
     let stdout = test_env.jj_cmd_success(&repo_path, &["restore", "file2", "file3"]);
     insta::assert_snapshot!(stdout, @r###"
-    Created 28647642d4a5 (no description set)
-    Working copy now at: 28647642d4a5 (no description set)
+    Created 569ce73d04fb (no description set)
+    Working copy now at: 569ce73d04fb (no description set)
     Added 0 files, modified 1 files, removed 1 files
     "###);
     let stdout = test_env.jj_cmd_success(&repo_path, &["diff", "-s"]);