feat(explorer): add optional Git line statistics

README.md

@@ -130,6 +130,11 @@ https://github.com/user-attachments/assets/64c41f01-dffe-4318-bce4-16eec8de356e
       focus_on_select = false,  -- Jump to modified pane after selecting a file (default: stay in explorer)
       auto_open_on_cursor = false, -- Rebind j/k/Down/Up in the explorer to also open the file under the cursor
       status_right_margin = 1,  -- Trailing cells between status symbol (M/A/D) and right edge; increase if Nerd Font icons clip it
+      line_stats = {
+        enabled = false,         -- Fetch and show Git line statistics
+        count_untracked = false, -- Count untracked file lines as insertions
+        max_untracked_bytes = 1024 * 1024, -- Skip larger untracked files
+      },
       ellipsis = "…",          -- Text appended to truncated Explorer regions
       formatters = {  -- Optional function(ctx) -> line layout callbacks; omit to use the built-ins
         file = nil,   -- File rows
@@ -233,6 +238,10 @@ https://github.com/user-attachments/assets/64c41f01-dffe-4318-bce4-16eec8de356e
 
 `diff.filler_text` accepts any non-empty text pattern and repeats it across filler rows. Set it to `""` to hide the decoration while preserving the rows that keep side-by-side and conflict panes aligned. Non-empty patterns use the `CodeDiffFiller` highlight group.
 
+Explorer line statistics are disabled by default because they require extra Git queries and consume space in the default 40-column Explorer. Set `explorer.line_stats.enabled = true` to show per-file Git numstat counts and group totals in status, one-revision, and two-revision modes. Untracked files have no stats unless `count_untracked = true`; files larger than `max_untracked_bytes` are not read (1 MiB by default).
+
+Files use `+12 -4` (`bin` for binary files), and group headings use `Changes (3 · +42 -8)`. Aggregate folder and group stats contain `files_changed`, `insertions`, `deletions`, `binary_files`, and `unavailable_files`.
+
 #### Explorer line formatters
 
 `explorer.formatters.file`, `folder`, and `group` replace the complete corresponding explorer row. Each callback receives row metadata and returns a layout:
@@ -254,13 +263,13 @@ https://github.com/user-attachments/assets/64c41f01-dffe-4318-bce4-16eec8de356e
 }
 ```
 
-A region contains styled `segments`. A numeric `truncate_priority` makes it truncatable; lower priorities truncate first. Regions without a priority stay fixed unless all content cannot fit. The renderer measures display cells, truncates with `explorer.ellipsis` (default `…`), right-aligns `right`, and preserves `min_gap` when space permits. The ellipsis can contain multiple characters and is clipped display-width-aware when necessary.
+A region contains styled `segments`. A numeric `truncate_priority` makes it truncatable; lower priorities truncate first. Regions without a priority stay fixed unless all content cannot fit. The renderer measures display cells, truncates with `explorer.ellipsis` (default `…`), right-aligns `right`, and preserves `min_gap` when space permits. The built-in file formatter truncates the directory, filename, then stats while keeping status fixed. The ellipsis can contain multiple characters and is clipped display-width-aware when necessary.
 
 Each segment is `{ text = string, hl? = highlight }`. `hl` accepts a Neovim highlight group, a `#RGB`/`#RRGGBB` foreground color, or a highlight definition such as `{ fg = "#3fb950", bold = true }`. Omitted highlights use `Normal`; selected file rows retain their selection background.
 
-File contexts contain `path`, `filename`, `directory`, `old_path`, `group`, `status`, `status_hl`, `status_right_margin`, `indent`, `indent_hl`, `icon`, and `icon_hl`. Folder contexts contain `name`, `path`, `group`, `file_count`, `files`, `indent`, `indent_hl`, `icon`, `icon_hl`, and `expanded`. Group contexts contain `name`, `label`, `file_count`, `files`, and `expanded`.
+File contexts contain `path`, `filename`, `directory`, `old_path`, `group`, `stats`, `status`, `status_hl`, `status_right_margin`, `indent`, `indent_hl`, `icon`, and `icon_hl`. Folder contexts contain `name`, `path`, `group`, `file_count`, `stats`, `files`, `indent`, `indent_hl`, `icon`, `icon_hl`, and `expanded`. Group contexts contain `name`, `label`, `file_count`, `stats`, `files`, and `expanded`. `stats` is `nil` when line statistics are disabled.
 
-Folder and group `files` contain `{ path, old_path, group, status }` entries for every represented file. The built-in callbacks are exported by `codediff.ui.explorer.formatters` and return fresh layouts that can be assigned directly or wrapped.
+Folder and group `files` contain `{ path, old_path, group, status, stats }` entries for every represented file. The built-in callbacks are exported by `codediff.ui.explorer.formatters` and return fresh layouts that can be assigned directly or wrapped.
 
 ```lua
 require("codediff").setup({
@@ -701,6 +710,10 @@ The plugin defines highlight groups matching VSCode's diff colors:
 - `CodeDiffFiller` - Gray foreground for non-empty filler line patterns
 - `CodeDiffLineMove` - Background for moved code lines (derived from DiffChange)
 - `CodeDiffMoveTo` - Sign column and annotation color for move indicators
+- `CodeDiffExplorerStatFiles` - Explorer file counts
+- `CodeDiffExplorerStatInsertions` - Explorer insertion counts
+- `CodeDiffExplorerStatDeletions` - Explorer deletion counts
+- `CodeDiffExplorerStatBinary` - Explorer binary-file labels
 
 <details open>
 <summary><b>📸 Visual Examples</b> (click to collapse)</summary>

doc/codediff.txt

@@ -262,6 +262,11 @@ Setup entry point:
       },
       untracked = "all",  -- "all", "normal" (collapse dirs), or "no" (skip untracked; use for huge work trees like GIT_WORK_TREE=$HOME, #389)
       status_right_margin = 1,
+      line_stats = {
+        enabled = false,
+        count_untracked = false,
+        max_untracked_bytes = 1024 * 1024,
+      },
       ellipsis = "…",
       formatters = {
         file = nil,
@@ -339,6 +344,19 @@ Setup entry point:
   })
 <
 
+EXPLORER LINE STATISTICS                  *codediff-explorer-line-statistics*
+
+Explorer line statistics are disabled by default because they require extra Git
+queries and consume space in the default 40-column Explorer. With `enabled =
+true`, tracked files show Git numstat counts and group headings show totals in
+status, one-revision, and two-revision modes. Untracked files have no stats
+unless `count_untracked = true`; files larger than `max_untracked_bytes` are not
+read (1 MiB by default).
+
+Files use `+12 -4` (`bin` for binary files); group headings use `Changes (3 ·
++42 -8)`. Aggregate folder and group stats contain `files_changed`,
+`insertions`, `deletions`, `binary_files`, and `unavailable_files`.
+
 EXPLORER LINE FORMATTERS                    *codediff-explorer-line-formatters*
 
 `explorer.formatters.file`, `folder`, and `group` replace the complete
@@ -365,24 +383,26 @@ A region contains styled `segments`. A numeric `truncate_priority` makes it
 truncatable; lower priorities truncate first. Regions without one stay fixed
 unless all content cannot fit. The renderer measures display cells, truncates
 with `explorer.ellipsis` (default `…`), right-aligns `right`, and preserves
-`min_gap` when space permits. The ellipsis can contain multiple characters and
-is clipped display-width-aware when necessary.
+`min_gap` when space permits. The built-in file formatter truncates the
+directory, filename, then stats while keeping status fixed. The ellipsis can
+contain multiple characters and is clipped display-width-aware when necessary.
 
 Each segment is `{ text = string, hl? = highlight }`. `hl` accepts a Neovim
 highlight group, a `#RGB`/`#RRGGBB` foreground color, or a highlight definition
 such as `{ fg = "#3fb950", bold = true }`. Omitted highlights use `Normal`;
 selected file rows retain their selection background.
 
 File contexts contain `path`, `filename`, `directory`, `old_path`, `group`,
-`status`, `status_hl`, `status_right_margin`, `indent`, `indent_hl`, `icon`, and
-`icon_hl`.
+`stats`, `status`, `status_hl`, `status_right_margin`, `indent`, `indent_hl`,
+`icon`, and `icon_hl`.
 
-Folder contexts contain `name`, `path`, `group`, `file_count`, `files`,
+Folder contexts contain `name`, `path`, `group`, `file_count`, `stats`, `files`,
 `indent`, `indent_hl`, `icon`, `icon_hl`, and `expanded`. Group contexts contain
-`name`, `label`, `file_count`, `files`, and `expanded`.
+`name`, `label`, `file_count`, `stats`, `files`, and `expanded`. `stats` is nil
+when line statistics are disabled.
 
-Folder and group `files` contain `{ path, old_path, group, status }` entries for
-every represented file. Built-in callbacks are exported by
+Folder and group `files` contain `{ path, old_path, group, status, stats }`
+entries for every represented file. Built-in callbacks are exported by
 `codediff.ui.explorer.formatters` and return fresh layouts that can be assigned
 directly or wrapped.
 
@@ -464,6 +484,10 @@ Explorer & history git status highlights (customizable):
 - CodeDiffStatusUntracked   Untracked files (links to DiagnosticInfo)
 - CodeDiffStatusConflict    Conflicting files (links to DiagnosticError)
 - CodeDiffExplorerSelected  Selected file background (links to Visual)
+- CodeDiffExplorerStatFiles File counts (links to Number)
+- CodeDiffExplorerStatInsertions Insertions (links to Added or DiagnosticOk)
+- CodeDiffExplorerStatDeletions Deletions (links to Removed or DiagnosticError)
+- CodeDiffExplorerStatBinary Binary labels (links to NonText)
 
 Override in your config or colorscheme:
 >lua

doc/tags

@@ -6,6 +6,7 @@ codediff-commands	codediff.txt	/*codediff-commands*
 codediff-configuration	codediff.txt	/*codediff-configuration*
 codediff-events	codediff.txt	/*codediff-events*
 codediff-explorer-line-formatters	codediff.txt	/*codediff-explorer-line-formatters*
+codediff-explorer-line-statistics	codediff.txt	/*codediff-explorer-line-statistics*
 codediff-filler-text	codediff.txt	/*codediff-filler-text*
 codediff-highlight-groups	codediff.txt	/*codediff-highlight-groups*
 codediff-history	codediff.txt	/*codediff-history*

lua/codediff/commands.lua

@@ -420,7 +420,7 @@ local function handle_explorer(revision, revision2, global_opts, pathspec)
             return
           end
 
-          git.get_diff_revisions(commit_hash, commit_hash2, git_root, function(err_status, status_result)
+          git.get_diff_revisions_with_line_stats(commit_hash, commit_hash2, git_root, function(err_status, status_result)
             process_status(err_status, status_result, commit_hash, commit_hash2)
           end, pathspec)
         end)
@@ -436,13 +436,13 @@ local function handle_explorer(revision, revision2, global_opts, pathspec)
         end
 
         -- Get diff between revision and working tree
-        git.get_diff_revision(commit_hash, git_root, function(err_status, status_result)
+        git.get_diff_revision_with_line_stats(commit_hash, git_root, function(err_status, status_result)
           process_status(err_status, status_result, commit_hash, "WORKING")
         end, pathspec)
       end)
     else
       -- Get git status (current changes)
-      git.get_status(git_root, function(err_status, status_result)
+      git.get_status_with_line_stats(git_root, function(err_status, status_result)
         -- Pass nil for revisions to enable "Status Mode" in explorer (separate Staged/Unstaged groups)
         process_status(err_status, status_result, nil, nil)
       end, pathspec)

lua/codediff/config.lua

@@ -74,8 +74,13 @@ M.defaults = {
     auto_open_on_cursor = false, -- Rebind j/k/Down/Up in the explorer to also open the file under the cursor
     flatten_dirs = true, -- Flatten single-child directory chains in tree view (e.g., src/components/ui/)
     status_right_margin = 1, -- Trailing cells between the status symbol (M/A/D) and the right edge; increase if Nerd Font icons clip it
+    line_stats = {
+      enabled = false,
+      count_untracked = false,
+      max_untracked_bytes = 1024 * 1024,
+    },
     ellipsis = "…", -- Text appended to truncated Explorer regions
-    formatters = { -- nil = use the built-in from lua/codediff/ui/explorer/formatters.lua
+    formatters = { -- nil = use the built-in from lua/codediff/ui/explorer/formatters/
       file = nil, -- File rows: function(ctx) -> layout
       folder = nil, -- Directory rows in tree view: function(ctx) -> layout
       group = nil, -- Section headers such as Changes and Staged: function(ctx) -> layout

lua/codediff/core/git.lua

@@ -191,6 +191,172 @@ local function run_git_async(args, opts, callback)
   end
 end
 
+local function parse_numstat(output)
+  local stats = {}
+  local records = vim.split(output or "", "\0", { plain = true })
+  for index, record in ipairs(records) do
+    local insertions, deletions, path = record:match("^([^\t]+)\t([^\t]+)\t(.*)$")
+    if insertions then
+      path = path ~= "" and path or records[index + 2]
+      if path and path ~= "" then
+        stats[path] = insertions == "-" and { insertions = 0, deletions = 0, binary = true }
+          or { insertions = tonumber(insertions) or 0, deletions = tonumber(deletions) or 0, binary = false }
+      end
+    end
+  end
+  return stats
+end
+
+local function get_untracked_line_stats(path, max_bytes)
+  local uv = vim.uv or vim.loop
+  local stat = uv.fs_stat(path)
+  if not stat or stat.type ~= "file" or stat.size > max_bytes then
+    return nil
+  end
+
+  local fd = uv.fs_open(path, "r", 438)
+  if not fd then
+    return nil
+  end
+  local data = uv.fs_read(fd, stat.size, 0) or ""
+  uv.fs_close(fd)
+  if data:find("\0", 1, true) then
+    return { insertions = 0, deletions = 0, binary = true }
+  end
+
+  local _, newlines = data:gsub("\n", "")
+  local final_line = #data > 0 and data:sub(-1) ~= "\n" and 1 or 0
+  return { insertions = newlines + final_line, deletions = 0, binary = false }
+end
+
+local function attach_line_stats(entries, stats)
+  for _, entry in ipairs(entries or {}) do
+    entry.line_stats = stats[entry.path]
+  end
+end
+
+local function attach_untracked_line_stats(entries, git_root, max_bytes)
+  for _, entry in ipairs(entries or {}) do
+    if entry.status == "??" then
+      entry.line_stats = get_untracked_line_stats(git_root .. "/" .. entry.path, max_bytes)
+    end
+  end
+end
+
+local function collect_line_stats(git_root, requests, callback)
+  local remaining = #requests
+  local first_error
+  for _, request in ipairs(requests) do
+    run_git_async(request.args, { cwd = git_root }, function(err, output)
+      first_error = first_error or err
+      if not err then
+        local stats = parse_numstat(output)
+        for _, entries in ipairs(request.entries) do
+          attach_line_stats(entries, stats)
+        end
+      end
+      remaining = remaining - 1
+      if remaining == 0 then
+        callback(first_error)
+      end
+    end)
+  end
+end
+
+local function line_stats_options()
+  return (config.options.explorer or {}).line_stats or {}
+end
+
+function M.get_status_with_line_stats(git_root, callback, pathspec)
+  local options = line_stats_options()
+  if not options.enabled then
+    M.get_status(git_root, callback, pathspec)
+    return
+  end
+
+  M.get_status(git_root, function(err, result)
+    if err then
+      callback(err, nil)
+      return
+    end
+    collect_line_stats(git_root, {
+      {
+        args = vim.list_extend({ "diff", "--numstat", "-z", "-M", "--" }, pathspec or {}),
+        entries = { result.unstaged, result.conflicts },
+      },
+      {
+        args = vim.list_extend({ "diff", "--cached", "--numstat", "-z", "-M", "--" }, pathspec or {}),
+        entries = { result.staged },
+      },
+    }, function(stats_err)
+      if stats_err then
+        callback(stats_err, nil)
+        return
+      end
+      if options.count_untracked then
+        attach_untracked_line_stats(result.unstaged, git_root, options.max_untracked_bytes or 1024 * 1024)
+      end
+      callback(nil, result)
+    end)
+  end, pathspec)
+end
+
+function M.get_diff_revision_with_line_stats(revision, git_root, callback, pathspec)
+  local options = line_stats_options()
+  if not options.enabled then
+    M.get_diff_revision(revision, git_root, callback, pathspec)
+    return
+  end
+
+  M.get_diff_revision(revision, git_root, function(err, result)
+    if err then
+      callback(err, nil)
+      return
+    end
+    collect_line_stats(git_root, {
+      {
+        args = vim.list_extend({ "diff", "--numstat", "-z", "-M", revision, "--" }, pathspec or {}),
+        entries = { result.unstaged },
+      },
+    }, function(stats_err)
+      if stats_err then
+        callback(stats_err, nil)
+        return
+      end
+      if options.count_untracked then
+        attach_untracked_line_stats(result.unstaged, git_root, options.max_untracked_bytes or 1024 * 1024)
+      end
+      callback(nil, result)
+    end)
+  end, pathspec)
+end
+
+function M.get_diff_revisions_with_line_stats(rev1, rev2, git_root, callback, pathspec)
+  if not line_stats_options().enabled then
+    M.get_diff_revisions(rev1, rev2, git_root, callback, pathspec)
+    return
+  end
+
+  M.get_diff_revisions(rev1, rev2, git_root, function(err, result)
+    if err then
+      callback(err, nil)
+      return
+    end
+    collect_line_stats(git_root, {
+      {
+        args = vim.list_extend({ "diff", "--numstat", "-z", "-M", rev1, rev2, "--" }, pathspec or {}),
+        entries = { result.unstaged },
+      },
+    }, function(stats_err)
+      if stats_err then
+        callback(stats_err, nil)
+        return
+      end
+      callback(nil, result)
+    end)
+  end, pathspec)
+end
+
 -- ATOMIC ASYNC OPERATIONS
 -- All functions below are simple, atomic git operations