feat(move): Add --fixup to squash moved commits into the destination

On disk squashes are more conflict prone than in memory.

Author: claytonrcarter

git-branchless/src/commands/mod.rs

@@ -223,6 +223,7 @@ fn do_main_and_drop_locals() -> eyre::Result<i32> {
             dest,
             base,
             exact,
+            fixup,
             insert,
             move_options,
         } => r#move::r#move(
@@ -232,6 +233,7 @@ fn do_main_and_drop_locals() -> eyre::Result<i32> {
             dest,
             base,
             exact,
+            fixup,
             insert,
             &move_options,
         )?,

git-branchless/src/commands/move.rs

@@ -64,6 +64,7 @@ pub fn r#move(
     dest: Option<Revset>,
     bases: Vec<Revset>,
     exacts: Vec<Revset>,
+    fixup: bool,
     insert: bool,
     move_options: &MoveOptions,
 ) -> eyre::Result<ExitCode> {
@@ -255,7 +256,7 @@ pub fn r#move(
             let commits_to_move = commits_to_move.union(&union_all(
                 &exact_components.values().cloned().collect::<Vec<_>>(),
             ));
-            let commits_to_move = if insert {
+            let commits_to_move = if insert || fixup {
                 commits_to_move.union(&dag.query().children(CommitSet::from(dest_oid))?)
             } else {
                 commits_to_move
@@ -274,7 +275,18 @@ pub fn r#move(
 
         let source_roots = dag.query().roots(source_oids.clone())?;
         for source_root in commit_set_to_vec(&source_roots)? {
-            builder.move_subtree(source_root, vec![dest_oid])?;
+            if fixup {
+                let commits = dag
+                    .query()
+                    .descendants(CommitSet::from(source_root))?
+                    .difference(&dag.obsolete_commits);
+                let commits = commit_set_to_vec(&commits)?;
+                for commit in commits.iter() {
+                    builder.fixup_commit(*commit, dest_oid)?;
+                }
+            } else {
+                builder.move_subtree(source_root, vec![dest_oid])?;
+            }
         }
 
         let component_roots: CommitSet = exact_components.keys().cloned().collect();
@@ -383,7 +395,14 @@ pub fn r#move(
                 }
             }
 
-            builder.move_subtree(component_root, vec![component_dest_oid])?;
+            if fixup {
+                let commits = commit_set_to_vec(component)?;
+                for commit in commits.iter() {
+                    builder.fixup_commit(*commit, dest_oid)?;
+                }
+            } else {
+                builder.move_subtree(component_root, vec![component_dest_oid])?;
+            }
         }
 
         if insert {

git-branchless/src/opts.rs

@@ -311,6 +311,10 @@ pub enum Command {
         #[clap(value_parser, short = 'd', long = "dest")]
         dest: Option<Revset>,
 
+        /// Combine the moved commits and squash into the destination commit.
+        #[clap(action, short = 'F', long = "fixup", conflicts_with = "insert")]
+        fixup: bool,
+
         /// Insert the subtree between the destination and it's children, if any.
         /// Only supported if the moved subtree has a single head.
         #[clap(action, short = 'I', long = "insert")]