feat: Spin out/off branch

lua/neogit/lib/git/status.lua

@@ -153,6 +153,10 @@ local status = {
   unstage_all = function()
     git.cli.reset.call()
   end,
+  is_dirty = function()
+    local repo = require("neogit.lib.git.repository")
+    return #repo.staged.items > 0 or #repo.unstaged.items > 0
+  end
 }
 
 status.register = function(meta)

lua/neogit/popups/branch/actions.lua

@@ -22,6 +22,46 @@ local function parse_remote_branch_name(ref)
   return remote, branch_name
 end
 
+local function spin_off_branch(checkout)
+  if git.status.is_dirty() and not checkout then
+    notif.create("Staying on HEAD due to uncommitted changes", vim.log.levels.INFO)
+    checkout = true
+  end
+
+  local name = input.get_user_input("branch > ")
+  if not name or name == "" then
+    return
+  end
+
+  name, _ = name:gsub("%s", "-")
+  git.branch.create(name)
+
+  local current_branch_name = git.branch.current_full_name()
+
+  if checkout then
+    git.cli.checkout.branch(name).call_sync()
+  end
+
+  local upstream = git.branch.upstream()
+  if upstream then
+    if checkout then
+      git.log.update_ref(current_branch_name, upstream)
+    else
+      git.cli.reset.hard.args(upstream).call()
+    end
+  end
+end
+
+M.spin_off_branch = operation("spin_off_branch", function()
+  spin_off_branch(true)
+  status.refresh(true, "spin_off_branch")
+end)
+
+M.spin_out_branch = operation("spin_out_branch", function()
+  spin_off_branch(false)
+  status.refresh(true, "spin_out_branch")
+end)
+
 M.checkout_branch_revision = operation("checkout_branch_revision", function(popup)
   local selected_branch = FuzzyFinderBuffer.new(git.branch.get_all_branches()):open_async()
   if not selected_branch then

lua/neogit/popups/branch/init.lua

@@ -35,11 +35,11 @@ function M.create()
     :action("l", "local branch", actions.checkout_local_branch)
     :new_action_group()
     :action("c", "new branch", actions.checkout_create_branch)
-    :action("s", "new spin-off")
+    :action("s", "new spin-off", actions.spin_off_branch)
     :action("w", "new worktree")
     :new_action_group("Create")
     :action("n", "new branch", actions.create_branch)
-    :action("S", "new spin-out")
+    :action("S", "new spin-out", actions.spin_out_branch)
     :action("W", "new worktree")
     :new_action_group("Do")
     :action("C", "Configure...", actions.configure_branch)

tests/specs/neogit/operations_spec.lua

@@ -1,4 +1,5 @@
-require("plenary.async").tests.add_to_env()
+local async = require("plenary.async")
+async.tests.add_to_env()
 local eq = assert.are.same
 local operations = require("neogit.operations")
 local harness = require("tests.util.git_harness")
@@ -110,4 +111,100 @@ describe("branch popup", function()
       assert.False(vim.tbl_contains(get_git_branches(), "second-branch"))
     end)
   )
+
+  describe("spin out", function()
+    it(
+      "moves unpushed commits to a new branch unchecked out branch",
+      in_prepared_repo(function()
+        util.system([[
+          git reset --hard origin/master
+          touch feature.js
+          git add .
+          git commit -m 'some feature'
+        ]])
+        async.util.block_on(status.reset)
+
+        local input_branch = "spin-out-branch"
+        input.values = { input_branch }
+
+        local branch_before = get_current_branch()
+        local commit_before = get_git_rev(branch_before)
+
+        local remote_commit = get_git_rev("origin/" .. branch_before)
+
+        act("bS<cr><cr>")
+        operations.wait("spin_out_branch")
+
+        local branch_after = get_current_branch()
+
+        eq(branch_after, branch_before)
+        eq(get_git_rev(input_branch), commit_before)
+        eq(get_git_rev(branch_before), remote_commit)
+      end)
+    )
+
+    it(
+      "checks out the new branch if uncommitted changes present",
+      in_prepared_repo(function()
+        util.system([[
+          git reset --hard origin/master
+          touch feature.js
+          git add .
+          git commit -m 'some feature'
+          touch wip.js
+          git add .
+        ]])
+        async.util.block_on(status.reset)
+
+        local input_branch = "spin-out-branch"
+        input.values = { input_branch }
+
+        local branch_before = get_current_branch()
+        local commit_before = get_git_rev(branch_before)
+
+        local remote_commit = get_git_rev("origin/" .. branch_before)
+
+        act("bS<cr><cr>")
+        operations.wait("spin_out_branch")
+
+        local branch_after = get_current_branch()
+
+        eq(branch_after, input_branch)
+        eq(get_git_rev(branch_after), commit_before)
+        eq(get_git_rev(branch_before), remote_commit)
+      end)
+    )
+  end)
+
+  describe("spin off", function()
+    it(
+      "moves unpushed commits to a new checked out branch",
+      in_prepared_repo(function()
+        util.system([[
+          git reset --hard origin/master
+          touch feature.js
+          git add .
+          git commit -m 'some feature'
+        ]])
+        async.util.block_on(status.reset)
+
+        local input_branch = "spin-off-branch"
+        input.values = { input_branch }
+
+        local branch_before = get_current_branch()
+        local commit_before = get_git_rev(branch_before)
+
+        local remote_commit = get_git_rev("origin/" .. branch_before)
+
+        act("bs<cr><cr>")
+        operations.wait("spin_off_branch")
+
+        local branch_after = get_current_branch()
+
+        eq(branch_after, input_branch)
+        eq(get_git_rev(branch_after), commit_before)
+        eq(get_git_rev(branch_before), remote_commit)
+      end)
+    )
+  end)
 end)