cli: Support renaming workspaces

fixes jj-vcs#4342

CHANGELOG.md

@@ -50,6 +50,8 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
   (inherit from parent; default), `full` (full working copy), or `empty` (the
   empty working copy).
 
+* New command `jj workspace rename` that can rename the current workspace.
+
 * `jj op log` gained an option to include operation diffs.
 
 * `jj git clone` now accepts a `--remote <REMOTE NAME>` option, which

cli/examples/custom-working-copy/main.rs

@@ -250,6 +250,10 @@ impl LockedWorkingCopy for LockedConflictsWorkingCopy {
         self.inner.check_out(commit)
     }
 
+    fn rename_workspace(&mut self, new_workspace_id: WorkspaceId) {
+        self.inner.rename_workspace(new_workspace_id);
+    }
+
     fn reset(&mut self, commit: &Commit) -> Result<(), ResetError> {
         self.inner.reset(commit)
     }

cli/src/command_error.rs

@@ -46,6 +46,7 @@ use jj_lib::revset::RevsetParseErrorKind;
 use jj_lib::revset::RevsetResolutionError;
 use jj_lib::signing::SignInitError;
 use jj_lib::str_util::StringPatternParseError;
+use jj_lib::view::RenameWorkspaceError;
 use jj_lib::working_copy::ResetError;
 use jj_lib::working_copy::SnapshotError;
 use jj_lib::working_copy::WorkingCopyStateError;
@@ -264,6 +265,12 @@ impl From<CheckOutCommitError> for CommandError {
     }
 }
 
+impl From<RenameWorkspaceError> for CommandError {
+    fn from(err: RenameWorkspaceError) -> Self {
+        user_error_with_message("Failed to rename a workspace", err)
+    }
+}
+
 impl From<BackendError> for CommandError {
     fn from(err: BackendError) -> Self {
         match &err {

cli/src/commands/workspace/mod.rs

@@ -15,6 +15,7 @@
 mod add;
 mod forget;
 mod list;
+mod rename;
 mod root;
 mod update_stale;
 
@@ -27,6 +28,8 @@ use self::forget::cmd_workspace_forget;
 use self::forget::WorkspaceForgetArgs;
 use self::list::cmd_workspace_list;
 use self::list::WorkspaceListArgs;
+use self::rename::cmd_workspace_rename;
+use self::rename::WorkspaceRenameArgs;
 use self::root::cmd_workspace_root;
 use self::root::WorkspaceRootArgs;
 use self::update_stale::cmd_workspace_update_stale;
@@ -51,6 +54,7 @@ pub(crate) enum WorkspaceCommand {
     Add(WorkspaceAddArgs),
     Forget(WorkspaceForgetArgs),
     List(WorkspaceListArgs),
+    Rename(WorkspaceRenameArgs),
     Root(WorkspaceRootArgs),
     UpdateStale(WorkspaceUpdateStaleArgs),
 }
@@ -65,6 +69,7 @@ pub(crate) fn cmd_workspace(
         WorkspaceCommand::Add(args) => cmd_workspace_add(ui, command, args),
         WorkspaceCommand::Forget(args) => cmd_workspace_forget(ui, command, args),
         WorkspaceCommand::List(args) => cmd_workspace_list(ui, command, args),
+        WorkspaceCommand::Rename(args) => cmd_workspace_rename(ui, command, args),
         WorkspaceCommand::Root(args) => cmd_workspace_root(ui, command, args),
         WorkspaceCommand::UpdateStale(args) => cmd_workspace_update_stale(ui, command, args),
     }

cli/src/commands/workspace/rename.rs

@@ -0,0 +1,78 @@
+// Copyright 2020 The Jujutsu Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use jj_lib::op_store::WorkspaceId;
+use tracing::instrument;
+
+use crate::cli_util::CommandHelper;
+use crate::command_error::user_error;
+use crate::command_error::CommandError;
+use crate::ui::Ui;
+
+/// Renames the current workspace
+#[derive(clap::Args, Clone, Debug)]
+pub struct WorkspaceRenameArgs {
+    /// The name of the workspace to update to.
+    new_workspace_name: String,
+}
+
+#[instrument(skip_all)]
+pub fn cmd_workspace_rename(
+    ui: &mut Ui,
+    command: &CommandHelper,
+    args: &WorkspaceRenameArgs,
+) -> Result<(), CommandError> {
+    if args.new_workspace_name.is_empty() {
+        return Err(user_error("New workspace name cannot be empty"));
+    }
+
+    let mut workspace_command = command.workspace_helper(ui)?;
+
+    let old_workspace_id = workspace_command.working_copy().workspace_id().clone();
+    let new_workspace_id = WorkspaceId::new(args.new_workspace_name.clone());
+    if new_workspace_id == old_workspace_id {
+        writeln!(ui.status(), "Nothing changed.")?;
+        return Ok(());
+    }
+
+    if workspace_command
+        .repo()
+        .view()
+        .get_wc_commit_id(&old_workspace_id)
+        .is_none()
+    {
+        return Err(user_error(format!(
+            "The current workspace '{}' is not tracked in the repo.",
+            old_workspace_id.as_str()
+        )));
+    }
+
+    let mut tx = workspace_command.start_transaction().into_inner();
+    let (mut locked_ws, _wc_commit) = workspace_command.start_working_copy_mutation()?;
+
+    locked_ws
+        .locked_wc()
+        .rename_workspace(new_workspace_id.clone());
+
+    tx.repo_mut()
+        .rename_workspace(&old_workspace_id, new_workspace_id)?;
+    let repo = tx.commit(format!(
+        "Renamed workspace '{}' to '{}'",
+        old_workspace_id.as_str(),
+        args.new_workspace_name
+    ));
+    locked_ws.finish(repo.op_id().clone())?;
+
+    Ok(())
+}

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

@@ -98,6 +98,7 @@ This document contains the help content for the `jj` command-line program.
 * [`jj workspace add`↴](#jj-workspace-add)
 * [`jj workspace forget`↴](#jj-workspace-forget)
 * [`jj workspace list`↴](#jj-workspace-list)
+* [`jj workspace rename`↴](#jj-workspace-rename)
 * [`jj workspace root`↴](#jj-workspace-root)
 * [`jj workspace update-stale`↴](#jj-workspace-update-stale)
 
@@ -2144,6 +2145,7 @@ Each workspace also has own sparse patterns.
 * `add` — Add a workspace
 * `forget` — Stop tracking a workspace's working-copy commit in the repo
 * `list` — List workspaces
+* `rename` — Renames the current workspace
 * `root` — Show the current workspace root directory
 * `update-stale` — Update a workspace that has become stale
 
@@ -2208,6 +2210,18 @@ List workspaces
 
 
 
+## `jj workspace rename`
+
+Renames the current workspace
+
+**Usage:** `jj workspace rename <NEW_WORKSPACE_NAME>`
+
+###### **Arguments:**
+
+* `<NEW_WORKSPACE_NAME>` — The name of the workspace to update to
+
+
+
 ## `jj workspace root`
 
 Show the current workspace root directory

cli/tests/test_workspaces.rs

@@ -1078,6 +1078,93 @@ fn test_debug_snapshot() {
     "###);
 }
 
+#[test]
+fn test_workspaces_rename_nothing_changed() {
+    let test_env = TestEnvironment::default();
+    test_env.jj_cmd_ok(test_env.env_root(), &["git", "init", "main"]);
+    let main_path = test_env.env_root().join("main");
+    let (stdout, stderr) = test_env.jj_cmd_ok(&main_path, &["workspace", "rename", "default"]);
+    insta::assert_snapshot!(stdout, @"");
+    insta::assert_snapshot!(stderr, @r###"
+    Nothing changed.
+    "###);
+}
+
+#[test]
+fn test_workspaces_rename_new_workspace_name_already_used() {
+    let test_env = TestEnvironment::default();
+    test_env.jj_cmd_ok(test_env.env_root(), &["git", "init", "main"]);
+    let main_path = test_env.env_root().join("main");
+    test_env.jj_cmd_ok(
+        &main_path,
+        &["workspace", "add", "--name", "second", "../secondary"],
+    );
+    let stderr = test_env.jj_cmd_failure(&main_path, &["workspace", "rename", "second"]);
+    insta::assert_snapshot!(stderr, @r###"
+    Error: Failed to rename a workspace
+    Caused by: Workspace second already exists
+    "###);
+}
+
+#[test]
+fn test_workspaces_rename_forgotten_workspace() {
+    let test_env = TestEnvironment::default();
+    test_env.jj_cmd_ok(test_env.env_root(), &["git", "init", "main"]);
+    let main_path = test_env.env_root().join("main");
+    test_env.jj_cmd_ok(
+        &main_path,
+        &["workspace", "add", "--name", "second", "../secondary"],
+    );
+    test_env.jj_cmd_ok(&main_path, &["workspace", "forget", "second"]);
+    let secondary_path = test_env.env_root().join("secondary");
+    let stderr = test_env.jj_cmd_failure(&secondary_path, &["workspace", "rename", "third"]);
+    insta::assert_snapshot!(stderr, @r###"
+    Error: The current workspace 'second' is not tracked in the repo.
+    "###);
+}
+
+#[test]
+fn test_workspaces_rename_workspace() {
+    let test_env = TestEnvironment::default();
+    test_env.jj_cmd_ok(test_env.env_root(), &["git", "init", "main"]);
+    let main_path = test_env.env_root().join("main");
+    test_env.jj_cmd_ok(
+        &main_path,
+        &["workspace", "add", "--name", "second", "../secondary"],
+    );
+    let secondary_path = test_env.env_root().join("secondary");
+
+    // Both workspaces show up when we list them
+    let stdout = test_env.jj_cmd_success(&main_path, &["workspace", "list"]);
+    insta::assert_snapshot!(stdout, @r###"
+    default: qpvuntsm 230dd059 (empty) (no description set)
+    second: uuqppmxq 57d63245 (empty) (no description set)
+    "###);
+
+    let stdout = test_env.jj_cmd_success(&secondary_path, &["workspace", "rename", "third"]);
+    insta::assert_snapshot!(stdout, @"");
+
+    let stdout = test_env.jj_cmd_success(&main_path, &["workspace", "list"]);
+    insta::assert_snapshot!(stdout, @r###"
+    default: qpvuntsm 230dd059 (empty) (no description set)
+    third: uuqppmxq 57d63245 (empty) (no description set)
+    "###);
+
+    // Can see the working-copy commit in each workspace in the log output.
+    insta::assert_snapshot!(get_log_output(&test_env, &main_path), @r###"
+    ○  57d63245a308 third@
+    │ @  230dd059e1b0 default@
+    ├─╯
+    ◆  000000000000
+    "###);
+    insta::assert_snapshot!(get_log_output(&test_env, &secondary_path), @r###"
+    @  57d63245a308 third@
+    │ ○  230dd059e1b0 default@
+    ├─╯
+    ◆  000000000000
+    "###);
+}
+
 fn get_log_output(test_env: &TestEnvironment, cwd: &Path) -> String {
     let template = r#"
     separate(" ",

lib/src/local_working_copy.rs

@@ -1626,6 +1626,7 @@ impl WorkingCopy for LocalWorkingCopy {
             old_operation_id,
             old_tree_id,
             tree_state_dirty: false,
+            new_workspace_id: None,
         }))
     }
 }
@@ -1825,6 +1826,7 @@ pub struct LockedLocalWorkingCopy {
     old_operation_id: OperationId,
     old_tree_id: MergedTreeId,
     tree_state_dirty: bool,
+    new_workspace_id: Option<WorkspaceId>,
 }
 
 impl LockedWorkingCopy for LockedLocalWorkingCopy {
@@ -1872,6 +1874,10 @@ impl LockedWorkingCopy for LockedLocalWorkingCopy {
         Ok(stats)
     }
 
+    fn rename_workspace(&mut self, new_workspace_id: WorkspaceId) {
+        self.new_workspace_id = Some(new_workspace_id);
+    }
+
     fn reset(&mut self, commit: &Commit) -> Result<(), ResetError> {
         let new_tree = commit.tree()?;
         self.wc
@@ -1937,7 +1943,10 @@ impl LockedWorkingCopy for LockedLocalWorkingCopy {
                     err: Box::new(err),
                 })?;
         }
-        if self.old_operation_id != operation_id {
+        if self.old_operation_id != operation_id || self.new_workspace_id.is_some() {
+            if let Some(new_workspace_id) = self.new_workspace_id {
+                self.wc.checkout_state_mut().workspace_id = new_workspace_id;
+            }
             self.wc.checkout_state_mut().operation_id = operation_id;
             self.wc.save();
         }

lib/src/repo.rs

@@ -92,6 +92,7 @@ use crate::simple_op_store::SimpleOpStore;
 use crate::store::Store;
 use crate::submodule_store::SubmoduleStore;
 use crate::transaction::Transaction;
+use crate::view::RenameWorkspaceError;
 use crate::view::View;
 
 pub trait Repo {
@@ -1353,6 +1354,15 @@ impl MutableRepo {
         Ok(())
     }
 
+    pub fn rename_workspace(
+        &mut self,
+        old_workspace_id: &WorkspaceId,
+        new_workspace_id: WorkspaceId,
+    ) -> Result<(), RenameWorkspaceError> {
+        self.view_mut()
+            .rename_workspace(old_workspace_id, new_workspace_id)
+    }
+
     pub fn check_out(
         &mut self,
         workspace_id: WorkspaceId,

lib/src/view.rs

@@ -19,6 +19,7 @@ use std::collections::HashMap;
 use std::collections::HashSet;
 
 use itertools::Itertools;
+use thiserror::Error;
 
 use crate::backend::CommitId;
 use crate::op_store;
@@ -95,6 +96,29 @@ impl View {
         self.data.wc_commit_ids.remove(workspace_id);
     }
 
+    pub fn rename_workspace(
+        &mut self,
+        old_workspace_id: &WorkspaceId,
+        new_workspace_id: WorkspaceId,
+    ) -> Result<(), RenameWorkspaceError> {
+        if self.data.wc_commit_ids.contains_key(&new_workspace_id) {
+            return Err(RenameWorkspaceError::WorkspaceAlreadyExists {
+                workspace_id: new_workspace_id.as_str().to_owned(),
+            });
+        }
+        let wc_commit_id = self
+            .data
+            .wc_commit_ids
+            .remove(old_workspace_id)
+            .ok_or_else(|| RenameWorkspaceError::WorkspaceDoesNotExist {
+                workspace_id: old_workspace_id.as_str().to_owned(),
+            })?;
+        self.data
+            .wc_commit_ids
+            .insert(new_workspace_id, wc_commit_id);
+        Ok(())
+    }
+
     pub fn add_head(&mut self, head_id: &CommitId) {
         self.data.head_ids.insert(head_id.clone());
     }
@@ -369,3 +393,13 @@ impl View {
         &mut self.data
     }
 }
+
+/// Error from attempts to rename a workspace
+#[derive(Debug, Error)]
+pub enum RenameWorkspaceError {
+    #[error("Workspace {workspace_id} not found")]
+    WorkspaceDoesNotExist { workspace_id: String },
+
+    #[error("Workspace {workspace_id} already exists")]
+    WorkspaceAlreadyExists { workspace_id: String },
+}