feat(git/statusline): expose status via b:git_status, opt-in via enable()

init.lua

@@ -95,3 +95,5 @@ require("ts").setup({
     "https://github.com/tree-sitter-grammars/tree-sitter-yaml",
     "https://github.com/georgeharker/tree-sitter-zsh",
 })
+
+require("git.statusline").enable()

lua/core/options.lua

@@ -77,7 +77,7 @@ vim.opt.inccommand = "split"
 vim.opt.winborder = "rounded"
 vim.opt.confirm = true
 
-vim.opt.statusline = "%{expand('%:.')} %{%v:lua.require('git.statusline').render()%} %3(%m%)"
+vim.opt.statusline = "%{expand('%:.')} %{%get(b:, 'git_status_string', '')%} %3(%m%)"
     .. " %="
     .. " %{%v:lua.vim.diagnostic.status()%}"
     .. " %{&filetype} %{&fileencoding} %{&fileformat}"

lua/git/repo.lua

@@ -220,6 +220,7 @@ end
 
 ---@return string?
 function Repo:head()
+    return self:get_cached("head", function(self)
         local f = io.open(vim.fs.joinpath(self.gitdir, "HEAD"), "r")
         if not f then
             return nil
@@ -238,6 +239,7 @@ function Repo:head()
             return sha:sub(1, 7)
         end
         return nil
+    end)
 end
 
 ---@return string[]
@@ -408,7 +410,7 @@ end
 ---@return string
 local function path_for_buf(buf)
     local path = vim.api.nvim_buf_get_name(buf)
-    if path == "" or path:match("^%a+://") then
+    if path == "" or util.is_uri(path) then
         return vim.fn.getcwd()
     end
     return vim.fn.resolve(path)
@@ -514,7 +516,7 @@ local function is_worktree_buf(buf)
         return false
     end
     local path = vim.api.nvim_buf_get_name(buf)
-    return path ~= "" and not path:match("^%a+://")
+    return path ~= "" and not util.is_uri(path)
 end
 
 ---@param buf? integer

lua/git/statusline.lua

@@ -1,31 +1,109 @@
 local repo = require("git.repo")
+local util = require("git.util")
 
 local M = {}
 
+---@class ow.Git.Statusline.Status
+---@field head string?
+---@field entries ow.Git.Status.Entry[]
+---@field unstaged boolean
+---@field staged boolean
+---@field conflict boolean
+
+---@param entries ow.Git.Status.Entry[]
+---@param head string?
+---@return ow.Git.Statusline.Status
+local function build(entries, head)
+    local out = {
+        head = head,
+        entries = entries,
+        unstaged = false,
+        staged = false,
+        conflict = false,
+    }
+    for _, e in ipairs(entries) do
+        if e.kind == "unstaged" or e.kind == "untracked" then
+            out.unstaged = true
+        elseif e.kind == "staged" then
+            out.staged = true
+        elseif e.kind == "unmerged" then
+            out.conflict = true
+        end
+    end
+    return out
+end
+
+---@param entries ow.Git.Status.Entry[]
 ---@return string
-function M.render()
-    local r = repo.find()
-    if not r then
-        return ""
-    end
-    local name = vim.api.nvim_buf_get_name(0)
-    if name == "" then
-        return ""
-    end
-    local rel = vim.fs.relpath(r.worktree, vim.fn.resolve(name))
-    local list = rel and r.status.entries[rel]
-    if not list then
+local function render(entries)
+    if #entries == 0 then
         return ""
     end
     local parts = {}
-    for _, e in ipairs(list) do
+    for _, e in ipairs(entries) do
         table.insert(parts, string.format("%%#%s#%s%%*", e.hl, e.char))
     end
     return table.concat(parts, " ")
 end
 
-repo.on("refresh", function()
+---@param buf integer
+local function clear(buf)
+    vim.b[buf].git_status = nil
+    vim.b[buf].git_status_string = nil
+end
+
+---@param buf integer
+---@param r ow.Git.Repo?
+local function update_buf(buf, r)
+    if not vim.api.nvim_buf_is_valid(buf) then
+        return
+    end
+    local name = vim.api.nvim_buf_get_name(buf)
+    if name == "" or util.is_uri(name) then
+        return clear(buf)
+    end
+    r = r or repo.find(buf)
+    if not r then
+        return clear(buf)
+    end
+    local rel = vim.fs.relpath(r.worktree, vim.fn.resolve(name))
+    if not rel then
+        return clear(buf)
+    end
+    local entries = r.status.entries[rel] or {}
+    vim.b[buf].git_status = build(entries, r:head())
+    vim.b[buf].git_status_string = render(entries)
+end
+
+local enabled = false
+
+function M.enable()
+    if enabled then
+        return
+    end
+    enabled = true
+    repo.on("refresh", function(r)
+        for buf in pairs(r.buffers) do
+            if vim.api.nvim_buf_is_loaded(buf) then
+                update_buf(buf, r)
+            end
+        end
         vim.cmd.redrawstatus({ bang = true })
-end)
+    end)
+    vim.api.nvim_create_autocmd("BufWinEnter", {
+        group = vim.api.nvim_create_augroup(
+            "ow.git.statusline",
+            { clear = true }
+        ),
+        callback = function(args)
+            update_buf(args.buf, nil)
+        end,
+    })
+    for _, buf in ipairs(vim.api.nvim_list_bufs()) do
+        if vim.api.nvim_buf_is_loaded(buf) then
+            update_buf(buf, nil)
+        end
+    end
+end
 
 return M

lua/git/util.lua

@@ -20,6 +20,12 @@ function M.setup_scratch(buf, opts)
     end
 end
 
+---@param name string
+---@return boolean
+function M.is_uri(name)
+    return name:match("^%a+://") ~= nil
+end
+
 ---@param buf integer
 ---@param name string
 function M.set_buf_name(buf, name)