restore: add --into flag, make --to an alias to it

This is a part of jj-vcs#5394.

CHANGELOG.md

@@ -98,6 +98,9 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
   can be customized using `format_detailed_cryptographic_signature(signature)` and
   `format_short_cryptographic_signature(signature)`.
 
+* Added `--into` flag to `jj restore`, similarly to `jj squash` and `jj absorb`. It is
+  equivalent to `--to`, but `--into` is the recommended name.
+
 ### Fixed bugs
 
 * Fixed diff selection by external tools with `jj split`/`commit -i FILESETS`.

cli/src/commands/restore.rs

@@ -117,7 +117,7 @@ pub(crate) fn cmd_restore(
         return Err(user_error(
             "`jj restore` does not have a `--revision`/`-r` option. If you'd like to modify\nthe \
              *current* revision, use `--from`. If you'd like to modify a *different* \
-             revision,\nuse `--to` or `--changes-in`.",
+             revision,\nuse `--into` or `--changes-in`.",
         ));
     }
     if args.from.is_some() || args.into.is_some() {

cli/tests/test_restore_command.rs

@@ -35,7 +35,7 @@ fn test_restore() {
     insta::assert_snapshot!(stderr, @r###"
     Error: `jj restore` does not have a `--revision`/`-r` option. If you'd like to modify
     the *current* revision, use `--from`. If you'd like to modify a *different* revision,
-    use `--to` or `--changes-in`.
+    use `--into` or `--changes-in`.
     "###);
 
     // Restores from parent by default
@@ -94,7 +94,7 @@ fn test_restore() {
 
     // Can restore into other revision
     test_env.jj_cmd_ok(&repo_path, &["undo"]);
-    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["restore", "--to", "@-"]);
+    let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["restore", "--into", "@-"]);
     insta::assert_snapshot!(stdout, @"");
     insta::assert_snapshot!(stderr, @r###"
     Created rlvkpnrz ad805965 (no description set)
@@ -111,10 +111,10 @@ fn test_restore() {
     A file3
     "###);
 
-    // Can combine `--from` and `--to`
+    // Can combine `--from` and `--into`
     test_env.jj_cmd_ok(&repo_path, &["undo"]);
     let (stdout, stderr) =
-        test_env.jj_cmd_ok(&repo_path, &["restore", "--from", "@", "--to", "@-"]);
+        test_env.jj_cmd_ok(&repo_path, &["restore", "--from", "@", "--into", "@-"]);
     insta::assert_snapshot!(stdout, @"");
     insta::assert_snapshot!(stderr, @r###"
     Created rlvkpnrz f256040a (no description set)