completion: teach bookmark create, rename about prefix

cli/src/commands/bookmark/create.rs

@@ -13,6 +13,7 @@
 // limitations under the License.
 
 use clap::builder::NonEmptyStringValueParser;
+use clap_complete::ArgValueCandidates;
 use jj_lib::object_id::ObjectId as _;
 use jj_lib::op_store::RefTarget;
 
@@ -21,6 +22,7 @@ use crate::cli_util::CommandHelper;
 use crate::cli_util::RevisionArg;
 use crate::command_error::user_error_with_hint;
 use crate::command_error::CommandError;
+use crate::complete;
 use crate::ui::Ui;
 
 /// Create a new bookmark
@@ -34,7 +36,11 @@ pub struct BookmarkCreateArgs {
     revision: Option<RevisionArg>,
 
     /// The bookmarks to create
-    #[arg(required = true, value_parser = NonEmptyStringValueParser::new())]
+    #[arg(
+        required = true,
+        value_parser = NonEmptyStringValueParser::new(),
+        add = ArgValueCandidates::new(complete::push_bookmark_prefix),
+    )]
     names: Vec<String>,
 }
 

cli/src/commands/bookmark/rename.rs

@@ -32,6 +32,7 @@ pub struct BookmarkRenameArgs {
     old: String,
 
     /// The new name of the bookmark
+    #[arg(add = ArgValueCandidates::new(complete::bookmark_rename_new))]
     new: String,
 }
 

cli/src/complete.rs

@@ -44,6 +44,39 @@ pub fn local_bookmarks() -> Vec<CompletionCandidate> {
     })
 }
 
+pub fn push_bookmark_prefix() -> Vec<CompletionCandidate> {
+    with_jj(|_, config| {
+        Ok(match config.get::<String>("git.push-bookmark-prefix") {
+            Ok(prefix) => vec![CompletionCandidate::new(prefix)],
+            Err(_) => Vec::new(), // user didn't configure a prefix
+        })
+    })
+}
+
+/// A specific completion function for the `new` argument of `bookmark rename`.
+/// It suggests the `old` argument as first candidate, because the user may
+/// want to fix a typo.
+pub fn bookmark_rename_new() -> Vec<CompletionCandidate> {
+    let mut candidates = Vec::new();
+
+    let bookmark_to_rename = std::env::args_os()
+        .rev()
+        .filter_map(|arg| arg.into_string().ok())
+        .filter(|arg| !arg.starts_with("-"))
+        // The first non-flag argument is the one being completed, the second
+        // one is the "old" argument.
+        .nth(1);
+    if let Some(bookmark) = bookmark_to_rename {
+        candidates.push(CompletionCandidate::new(bookmark).display_order(Some(0)));
+    }
+    with_jj(|_, config| {
+        if let Ok(prefix) = config.get::<String>("git.push-bookmark-prefix") {
+            candidates.push(CompletionCandidate::new(prefix).display_order(Some(1)));
+        }
+        Ok(candidates)
+    })
+}
+
 /// Shell out to jj during dynamic completion generation
 ///
 /// In case of errors, print them and early return an empty vector.

cli/tests/test_completion.rs

@@ -76,3 +76,26 @@ fn test_global_arg_repository_is_respected() {
     );
     insta::assert_snapshot!(stdout, @"aaa");
 }
+
+#[test]
+fn test_push_bookmark_prefix() {
+    let mut test_env = TestEnvironment::default();
+
+    test_env.add_config(r#"git.push-bookmark-prefix = "fancy-prefix/""#);
+
+    test_env.add_env_var("COMPLETE", "fish");
+
+    let stdout = test_env.jj_cmd_success(
+        test_env.env_root(),
+        &["--", "jj", "bookmark", "create", "f"],
+    );
+    insta::assert_snapshot!(stdout, @"fancy-prefix/");
+    let stdout = test_env.jj_cmd_success(
+        test_env.env_root(),
+        &["--", "jj", "bookmark", "rename", "fancy-old-name", "f"],
+    );
+    insta::assert_snapshot!(stdout, @r"
+    fancy-old-name
+    fancy-prefix/
+    ");
+}