Add worktree switching + master diff workflow

init.lua

@@ -15,6 +15,7 @@ local modules = {
     { "config.filetree",      tier = "extra" },
     { "config.image",         tier = "extra", min = "0.13" },
     { "config.server",        tier = "extra" },
+    { "config.worktree",      tier = "extra" },
     { "config.agent_notify",  tier = "extra" },
 }
 

lua/config/worktree.lua

@@ -0,0 +1,154 @@
+local M = {}
+
+local function notify(msg, level)
+    vim.notify(msg, level or vim.log.levels.INFO, { title = "worktree" })
+end
+
+-- parses `git worktree list --porcelain`; entries are separated by blank
+-- lines but vim.split(trimempty) already drops those, so a fresh "worktree "
+-- line is what actually starts a new entry
+local function list_worktrees()
+    local res = vim.system({ "git", "worktree", "list", "--porcelain" }, { text = true }):wait()
+    if res.code ~= 0 then
+        local msg = res.stderr and res.stderr ~= "" and res.stderr or "git worktree list failed"
+        return nil, vim.trim(msg)
+    end
+
+    local worktrees, current = {}, nil
+    for _, line in ipairs(vim.split(res.stdout or "", "\n", { trimempty = true })) do
+        local path = line:match("^worktree (.+)$")
+        if path then
+            current = { path = path }
+            table.insert(worktrees, current)
+        elseif current then
+            local branch = line:match("^branch refs/heads/(.+)$")
+            if branch then
+                current.branch = branch
+            elseif line == "detached" then
+                current.detached = true
+            elseif line == "bare" then
+                current.bare = true
+            elseif line:match("^locked") then
+                current.locked = true
+            end
+        end
+    end
+    return worktrees
+end
+
+-- best-effort base branch for diffing when none is given: try the common
+-- local names first, then fall back to whatever the remote's HEAD points at
+local function default_base_branch()
+    for _, cand in ipairs({ "master", "main" }) do
+        if vim.system({ "git", "rev-parse", "--verify", "--quiet", cand }):wait().code == 0 then
+            return cand
+        end
+    end
+    local res = vim.system({ "git", "symbolic-ref", "--short", "refs/remotes/origin/HEAD" }, { text = true }):wait()
+    if res.code == 0 then
+        return (vim.trim(res.stdout):gsub("^origin/", ""))
+    end
+    return nil
+end
+
+-- switch the running session into a worktree: `opts.tab` opens a fresh tab
+-- first, otherwise the current tab's directory is changed in place
+function M.switch(path, opts)
+    opts = opts or {}
+    if opts.tab then
+        vim.cmd.tabnew()
+    end
+    local ok, err = pcall(vim.cmd.tcd, path)
+    if not ok then
+        notify("cd failed: " .. tostring(err), vim.log.levels.ERROR)
+        return
+    end
+    notify("worktree: " .. vim.fn.fnamemodify(path, ":~"))
+end
+
+function M.list()
+    local worktrees, err = list_worktrees()
+    if not worktrees then
+        notify(err, vim.log.levels.ERROR)
+        return
+    end
+    if #worktrees == 0 then
+        notify("no worktrees found", vim.log.levels.WARN)
+        return
+    end
+
+    local entries, lookup = {}, {}
+    for _, wt in ipairs(worktrees) do
+        local label = wt.branch or (wt.detached and "(detached)") or "(bare)"
+        local display = string.format("%-28s %s", label, vim.fn.fnamemodify(wt.path, ":~"))
+        table.insert(entries, display)
+        lookup[display] = wt
+    end
+
+    local function handle(display, switch_opts)
+        local wt = lookup[display]
+        if wt then
+            M.switch(wt.path, switch_opts)
+        end
+    end
+
+    local fzf_ok, fzf = pcall(require, "fzf-lua")
+    if fzf_ok then
+        fzf.fzf_exec(entries, {
+            prompt = "Worktrees> ",
+            actions = {
+                ["default"] = function(selected)
+                    handle(selected[1], { tab = true })
+                end,
+                ["ctrl-x"] = function(selected)
+                    handle(selected[1], { tab = false })
+                end,
+                ["ctrl-y"] = function(selected)
+                    local wt = lookup[selected[1]]
+                    if wt then
+                        vim.fn.setreg("+", wt.path)
+                        notify("copied: " .. wt.path)
+                    end
+                end,
+            },
+        })
+    else
+        vim.ui.select(entries, { prompt = "Worktree (Enter: new tab)" }, function(choice)
+            if choice then
+                handle(choice, { tab = true })
+            end
+        end)
+    end
+end
+
+-- diff the current worktree's working tree against `base` (default:
+-- master/main); this is exactly `git diff base`, just via diffview
+function M.diff_base(base)
+    base = base and base ~= "" and base or default_base_branch()
+    if not base then
+        notify("could not detect master/main; pass a ref, e.g. :WorktreeDiff main", vim.log.levels.WARN)
+        return
+    end
+    local ok = pcall(vim.cmd.DiffviewOpen, base)
+    if not ok then
+        notify("diffview.nvim is not installed", vim.log.levels.WARN)
+    end
+end
+
+vim.api.nvim_create_user_command("Worktrees", M.list, {
+    desc = "List worktrees; <CR> opens in a new tab, <C-x> in the current tab, <C-y> copies the path",
+})
+
+vim.api.nvim_create_user_command("WorktreeDiff", function(opts)
+    M.diff_base(opts.args)
+end, {
+    nargs = "?",
+    desc = "Diff current worktree against master/main (or the given ref)",
+})
+
+vim.keymap.set("n", "<leader>sw", M.list, { desc = "Worktrees (switch)" })
+vim.keymap.set("n", "<leader>gm", function()
+    M.diff_base()
+end, { desc = "Diff vs master/main" })
+
+return M