commit: add --reset-author option

CHANGELOG.md

@@ -76,6 +76,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   commits with no description) if authored by the current user.
   [#2000](https://github.com/martinvonz/jj/issues/2000)
 
+* `jj commit` now accepts `--reset-author` option to match `jj describe`.
+
 ### Fixed bugs
 
 * `jj git push` now ignores immutable commits when checking whether a

cli/src/commands/commit.rs

@@ -39,6 +39,16 @@ pub(crate) struct CommitArgs {
     /// Put these paths in the first commit
     #[arg(value_hint = clap::ValueHint::AnyPath)]
     paths: Vec<String>,
+    /// Reset the author to the configured user
+    ///
+    /// This resets the author name, email, and timestamp.
+    ///
+    /// You can use it in combination with the JJ_USER and JJ_EMAIL
+    /// environment variables to set a different author:
+    ///
+    /// $ JJ_USER='Foo Bar' [email protected] jj commit --reset-author
+    #[arg(long)]
+    reset_author: bool,
 }
 
 #[instrument(skip_all)]
@@ -102,12 +112,16 @@ new working-copy commit.
         edit_description(tx.base_repo(), &template, command.settings())?
     };
 
-    let new_commit = tx
+    let mut commit_builder = tx
         .mut_repo()
         .rewrite_commit(command.settings(), &commit)
         .set_tree_id(tree_id)
-        .set_description(description)
-        .write()?;
+        .set_description(description);
+    if args.reset_author {
+        let new_author = commit_builder.committer().clone();
+        commit_builder = commit_builder.set_author(new_author);
+    }
+    let new_commit = commit_builder.write()?;
     let workspace_ids = tx
         .mut_repo()
         .view()

cli/tests/cli-reference@.md.snap

@@ -437,6 +437,13 @@ Update the description and create a new change on top
 * `-i`, `--interactive` — Interactively choose which changes to include in the first commit
 * `--tool <NAME>` — Specify diff editor to be used (implies --interactive)
 * `-m`, `--message <MESSAGE>` — The change description to use (don't open editor)
+* `--reset-author` — Reset the author to the configured user
+
+   This resets the author name, email, and timestamp.
+
+   You can use it in combination with the JJ_USER and JJ_EMAIL environment variables to set a different author:
+
+   $ JJ_USER='Foo Bar' [email protected] jj commit --reset-author
 
 
 

cli/tests/test_commit_command.rs

@@ -217,6 +217,52 @@ fn test_commit_paths_warning() {
     "###);
 }
 
+#[test]
+fn test_commit_reset_author() {
+    let test_env = TestEnvironment::default();
+    test_env.jj_cmd_ok(test_env.env_root(), &["git", "init", "repo"]);
+    let repo_path = test_env.env_root().join("repo");
+
+    test_env.add_config(
+        r#"[template-aliases]
+'format_signature(signature)' = 'signature.name() ++ " " ++ signature.email() ++ " " ++ signature.timestamp()'"#,
+    );
+    let get_signatures = || {
+        test_env.jj_cmd_success(
+            &repo_path,
+            &[
+                "log",
+                "-r@",
+                "-T",
+                r#"format_signature(author) ++ "\n" ++ format_signature(committer)"#,
+            ],
+        )
+    };
+    insta::assert_snapshot!(get_signatures(), @r###"
+    @  Test User [email protected] 2001-02-03 04:05:07.000 +07:00
+    │  Test User [email protected] 2001-02-03 04:05:07.000 +07:00
+    ~
+    "###);
+
+    // Reset the author (the committer is always reset)
+    test_env.jj_cmd_ok(
+        &repo_path,
+        &[
+            "commit",
+            "--config-toml",
+            r#"user.name = "Ove Ridder"
+            user.email = "[email protected]""#,
+            "--reset-author",
+            "-m1",
+        ],
+    );
+    insta::assert_snapshot!(get_signatures(), @r###"
+    @  Ove Ridder [email protected] 2001-02-03 04:05:09.000 +07:00
+    │  Ove Ridder [email protected] 2001-02-03 04:05:09.000 +07:00
+    ~
+    "###);
+}
+
 fn get_log_output(test_env: &TestEnvironment, cwd: &Path) -> String {
     let template = r#"commit_id.short() ++ " " ++ description"#;
     test_env.jj_cmd_success(cwd, &["log", "-T", template])