next/prev: Implement next/prev --conflict

This allows users to jump to the next conflict in the ancestors or children of 
the start commit.

Continues work on #2126

CHANGELOG.md

@@ -109,6 +109,9 @@ No code changes (fixing Rust `Cargo.toml` stuff).
 * `ui.default-command` now accepts multiple string arguments, for more complex
   default `jj` commands.
 
+* `jj prev` and `jj next` have gained a `--conflict` flag which moves you
+  to the next conflict in a child commit.
+
 ### Fixed bugs
 
 * On Windows, symlinks in the repo are now supported when Developer Mode is enabled.

cli/src/commands/next.rs

@@ -63,6 +63,9 @@ pub(crate) struct NextArgs {
     /// edit`).
     #[arg(long)]
     edit: bool,
+    /// Jump to the next conflicted descendant.
+    #[arg(long, conflicts_with = "amount")]
+    conflict: bool,
 }
 
 pub fn choose_commit<'a>(
@@ -113,6 +116,7 @@ pub(crate) fn cmd_next(
             .view()
             .heads()
             .contains(current_wc_id);
+    let conflict = args.conflict;
     let current_wc = workspace_command.repo().store().get_commit(current_wc_id)?;
     // If we're editing, start at the working-copy commit.
     // Otherwise start from our direct parent.
@@ -124,7 +128,12 @@ pub(crate) fn cmd_next(
             _ => return Err(user_error("Cannot run `jj next` on a merge commit")),
         }
     };
-    let descendant_expression = RevsetExpression::commit(start_id.clone()).descendants_at(amount);
+    let base_expr = RevsetExpression::commit(start_id.clone());
+    let descendant_expression = if conflict {
+        base_expr.descendants().conflicts()
+    } else {
+        base_expr.descendants_at(amount)
+    };
     let target_expression = if edit {
         descendant_expression
     } else {

cli/src/commands/prev.rs

@@ -59,6 +59,9 @@ pub(crate) struct PrevArgs {
     /// Edit the parent directly, instead of moving the working-copy commit.
     #[arg(long)]
     edit: bool,
+    /// Jump to nearest the conflicted ancestor.
+    #[arg(long, conflicts_with = "amount")]
+    conflict: bool,
 }
 
 pub(crate) fn cmd_prev(
@@ -68,6 +71,7 @@ pub(crate) fn cmd_prev(
 ) -> Result<(), CommandError> {
     let mut workspace_command = command.workspace_helper(ui)?;
     let amount = args.amount;
+    let conflict = args.conflict;
     let current_wc_id = workspace_command
         .get_wc_commit_id()
         .ok_or_else(|| user_error("This command requires a working copy"))?;
@@ -86,7 +90,12 @@ pub(crate) fn cmd_prev(
             _ => return Err(user_error("Cannot run `jj prev` on a merge commit")),
         }
     };
-    let ancestor_expression = RevsetExpression::commit(start_id.clone()).ancestors_at(amount);
+    let base_expr = RevsetExpression::commit(start_id.clone());
+    let ancestor_expression = if conflict {
+        base_expr.ancestors().conflicts()
+    } else {
+        base_expr.ancestors_at(amount)
+    };
     let target_revset = if edit {
         ancestor_expression
     } else {

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

@@ -1181,6 +1181,10 @@ implied.
 
   Possible values: `true`, `false`
 
+* `--conflict` — Jump to the next conflicted descendant
+
+  Possible values: `true`, `false`
+
 
 
 
@@ -1385,6 +1389,10 @@ implied.
 
   Possible values: `true`, `false`
 
+* `--conflict` — Jump to nearest the conflicted ancestor
+
+  Possible values: `true`, `false`
+
 
 
 

cli/tests/test_next_prev_commands.rs

@@ -318,3 +318,55 @@ fn test_next_editing() {
     Parent commit      : kkmpptxz 3fa8931e (empty) third
     "###);
 }
+
+// #[test]
+// fn test_prev_conflict() {
+//     // Edit the third commit.
+//     let test_env = TestEnvironment::default();
+//     test_env.jj_cmd_ok(test_env.env_root(), &["init", "repo", "--git"]);
+//     let repo_path = test_env.env_root().join("repo");
+//     test_env.jj_cmd_ok(&repo_path, &["commit", "-m", "first"]);
+//     test_env.jj_cmd_ok(&repo_path, &["commit", "-m", "second"]);
+//     test_env.jj_cmd_ok(&repo_path, &["commit", "-m", "third"]);
+//     test_env.jj_cmd_ok(&repo_path, &["commit", "-m", "fourth"]);
+//     let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["prev", "--conflict"]);
+//     insta::assert_snapshot!(stdout, @"");
+//     insta::assert_snapshot!(stderr, @r###"
+//     Working copy now at: zsuskuln 009f88bf (empty) fourth
+//     Parent commit      : kkmpptxz 3fa8931e (empty) third
+//     "###);
+//     // --edit is implied when already editing a non-head commit
+//     let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["prev"]);
+//     insta::assert_snapshot!(stdout, @"");
+//     insta::assert_snapshot!(stderr, @r###"
+//     Working copy now at: yqosqzyt d2edc95b (empty) (no description set)
+//     Parent commit      : rlvkpnrz 5c52832c (empty) second
+//     "###);
+// }
+
+// #[test]
+// fn test_next_conflict() {
+//     // There is a conflict in the fourth commit, so after next we should create a
+//     // new revision on top of it.
+//     let test_env = TestEnvironment::default();
+//     test_env.jj_cmd_ok(test_env.env_root(), &["init", "repo", "--git"]);
+//     let repo_path = test_env.env_root().join("repo");
+//     test_env.jj_cmd_ok(&repo_path, &["commit", "-m", "first"]);
+//     test_env.jj_cmd_ok(&repo_path, &["commit", "-m", "second"]);
+//     test_env.jj_cmd_ok(&repo_path, &["commit", "-m", "third"]);
+//     test_env.jj_cmd_ok(&repo_path, &["commit", "-m", "fourth"]);
+//     test_env.jj_cmd_ok(&repo_path, &["edit", "@---"]);
+//     let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["next", "--conflict"]);
+//     insta::assert_snapshot!(stdout, @"");
+//     insta::assert_snapshot!(stderr, @r###"
+//     Working copy now at: kkmpptxz 3fa8931e (empty) third
+//     Parent commit      : rlvkpnrz 5c52832c (empty) second
+//     "###);
+//     // --edit is implied when already editing a non-head commit
+//     let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["next"]);
+//     insta::assert_snapshot!(stdout, @"");
+//     insta::assert_snapshot!(stderr, @r###"
+//     Working copy now at: zsuskuln 009f88bf (empty) fourth
+//     Parent commit      : kkmpptxz 3fa8931e (empty) third
+//     "###);
+// }