test(gitcommit): add comprehensive unit tests

lua/codecompanion/_extensions/gitcommit/buffer.lua

@@ -259,8 +259,11 @@ function Buffer._insert_commit_message(bufnr, message)
     vim.api.nvim_buf_set_lines(bufnr, #message_lines, #message_lines, false, { "" })
   end
 
-  -- Move cursor to beginning of commit message
-  vim.api.nvim_win_set_cursor(0, { 1, 0 })
+  -- Move cursor to beginning of commit message if buffer is visible
+  local winid = vim.fn.bufwinid(bufnr)
+  if winid ~= -1 then
+    vim.api.nvim_win_set_cursor(winid, { 1, 0 })
+  end
 
   vim.notify("Commit message generated and inserted!", vim.log.levels.INFO)
 end

lua/codecompanion/_extensions/gitcommit/config_validation.lua

@@ -34,6 +34,7 @@ M.schema = {
       keymap = { "string", "nil" },
       auto_generate = { "boolean", "nil" },
       auto_generate_delay = { "number", "nil" },
+      window_stability_delay = { "number", "nil" },
       skip_auto_generate_on_amend = { "boolean", "nil" },
     },
   },

lua/codecompanion/_extensions/gitcommit/git.lua

@@ -38,8 +38,7 @@ function Git.is_repository()
   end
 
   local function check_git_dir(path)
-    local sep = package.config:sub(1, 1)
-    local git_path = path .. sep .. ".git"
+    local git_path = GitUtils.path_join(path, ".git")
     local stat = vim.uv.fs_stat(git_path)
     return stat ~= nil
   end
@@ -58,8 +57,7 @@ function Git.is_repository()
     check_dir = parent
   end
 
-  local redirect = (vim.uv.os_uname().sysname == "Windows_NT") and " 2>nul" or " 2>/dev/null"
-  local cmd = "git rev-parse --is-inside-work-tree" .. redirect
+  local cmd = { "git", "rev-parse", "--is-inside-work-tree" }
   local result = vim.fn.system(cmd)
   local is_repo = vim.v.shell_error == 0 and vim.trim(result) == "true"
 
@@ -78,15 +76,13 @@ function Git.is_amending()
       return false
     end
 
-    local path_sep = package.config:sub(1, 1)
-    local commit_editmsg = git_dir .. path_sep .. "COMMIT_EDITMSG"
+    local commit_editmsg = GitUtils.path_join(git_dir, "COMMIT_EDITMSG")
     local stat = vim.uv.fs_stat(commit_editmsg)
     if not stat then
       return false
     end
 
-    local redirect = (vim.uv.os_uname().sysname == "Windows_NT") and " 2>nul" or " 2>/dev/null"
-    vim.fn.system("git rev-parse --verify HEAD" .. redirect)
+    vim.fn.system({ "git", "rev-parse", "--verify", "HEAD" })
     if vim.v.shell_error ~= 0 then
       return false
     end
@@ -185,7 +181,13 @@ function Git.get_contextual_diff()
     end
 
     local all_local_diff = vim.fn.system("git diff --no-ext-diff HEAD")
-    if vim.v.shell_error == 0 and GitUtils.trim(all_local_diff) ~= "" then
+    if vim.v.shell_error ~= 0 then
+      all_local_diff = vim.fn.system("git diff --no-ext-diff")
+      if vim.v.shell_error ~= 0 then
+        return nil, "git_operation_failed"
+      end
+    end
+    if GitUtils.trim(all_local_diff) ~= "" then
       local filtered_diff = Git._filter_diff(all_local_diff)
       if GitUtils.trim(filtered_diff) ~= "" then
         return filtered_diff, "unstaged_or_all_local"

lua/codecompanion/_extensions/gitcommit/git_utils.lua

@@ -217,7 +217,39 @@ end
 ---Check if running on Windows
 ---@return boolean
 function M.is_windows()
-  return vim.loop.os_uname().sysname == "Windows_NT"
+  return vim.uv.os_uname().sysname == "Windows_NT"
+end
+
+---Join path parts with platform-specific separator
+---Normalizes all parts to forward slashes internally, then converts to platform format
+---@param ... string Path parts to join
+---@return string joined_path
+function M.path_join(...)
+  local parts = { ... }
+  if #parts == 0 then
+    return ""
+  end
+
+  -- Normalize all parts to use forward slashes
+  local normalized = {}
+  for i, part in ipairs(parts) do
+    normalized[i] = part:gsub("\\+", "/")
+  end
+
+  -- Remove leading/trailing slashes from middle parts
+  for i = 2, #normalized - 1 do
+    normalized[i] = normalized[i]:gsub("^/", ""):gsub("/$", "")
+  end
+
+  -- Join with forward slashes
+  local result = table.concat(normalized, "/")
+
+  -- Convert to Windows backslashes if on Windows
+  if M.is_windows() then
+    result = result:gsub("/", "\\")
+  end
+
+  return result
 end
 
 ---Quote a string for shell command (cross-platform)

lua/codecompanion/_extensions/gitcommit/prompts/release_notes.lua

@@ -1,5 +1,26 @@
 local M = {}
 
+---@alias ReleaseNotesStyle "detailed" | "concise" | "changelog" | "marketing"
+
+---@class CommitInfo
+---@field hash string Full commit hash
+---@field subject string Commit subject line
+---@field body string|nil Commit body (optional)
+---@field author string|nil Author name (optional)
+---@field type string|nil Commit type from subject (feat, fix, etc.)
+
+---@class CommitAnalysis
+---@field features CommitInfo[]
+---@field fixes CommitInfo[]
+---@field breaking_changes CommitInfo[]
+---@field performance CommitInfo[]
+---@field documentation CommitInfo[]
+---@field refactoring CommitInfo[]
+---@field tests CommitInfo[]
+---@field chore CommitInfo[]
+---@field other CommitInfo[]
+---@field contributors table<string, number> Author -> commit count
+
 M.style_guides = {
   detailed = [[You are creating comprehensive release notes for developers.
 Write thorough explanations of changes with technical context.
@@ -37,7 +58,14 @@ WRITING GUIDELINES:
 - Merge similar commits into single entries when appropriate
 ]]
 
+---@param commit CommitInfo Commit information to format
+---@param include_hash boolean Whether to include commit hash
+---@return string Formatted commit entry
 local function format_commit(commit, include_hash)
+  if not commit or not commit.subject then
+    return "- (invalid commit data)"
+  end
+
   local parts = { "- ", commit.subject }
   if include_hash and commit.hash then
     table.insert(parts, string.format(" (%s)", commit.hash:sub(1, 7)))
@@ -51,8 +79,12 @@ local function format_commit(commit, include_hash)
   return table.concat(parts)
 end
 
+---@param name string Category name
+---@param commits CommitInfo[] List of commits in this category
+---@param include_hash boolean Whether to include commit hashes
+---@return string|nil Formatted category section or nil if empty
 local function format_category(name, commits, include_hash)
-  if #commits == 0 then
+  if not commits or #commits == 0 then
     return nil
   end
   local lines = { string.format("\n### %s", name) }
@@ -62,7 +94,24 @@ local function format_category(name, commits, include_hash)
   return table.concat(lines, "\n")
 end
 
+---@param commits CommitInfo[] List of commits to analyze
+---@return CommitAnalysis Analysis results with categorized commits and contributor counts
 function M.analyze_commits(commits)
+  if type(commits) ~= "table" then
+    return {
+      features = {},
+      fixes = {},
+      breaking_changes = {},
+      performance = {},
+      documentation = {},
+      refactoring = {},
+      tests = {},
+      chore = {},
+      other = {},
+      contributors = {},
+    }
+  end
+
   local analysis = {
     features = {},
     fixes = {},
@@ -77,11 +126,18 @@ function M.analyze_commits(commits)
   }
 
   for _, commit in ipairs(commits) do
-    analysis.contributors[commit.author] = (analysis.contributors[commit.author] or 0) + 1
+    -- Track contributors (skip nil authors)
+    if commit.author then
+      analysis.contributors[commit.author] = (analysis.contributors[commit.author] or 0) + 1
+    end
 
-    local is_breaking = commit.subject:match("^%w+!:") -- feat!: xxx
-      or commit.subject:match("^%w+%b()!:") -- feat(scope)!: xxx
-      or commit.subject:upper():match("BREAKING")
+    -- Check for breaking changes (nil-safe)
+    local is_breaking = false
+    if commit.subject then
+      is_breaking = commit.subject:match("^%w+!:") -- feat!: xxx
+        or commit.subject:match("^%w+%b()!:") -- feat(scope)!: xxx
+        or commit.subject:upper():match("BREAKING")
+    end
 
     if is_breaking then
       table.insert(analysis.breaking_changes, commit)
@@ -107,7 +163,20 @@ function M.analyze_commits(commits)
   return analysis
 end
 
+---@param commits CommitInfo[] List of commits to analyze
+---@param style ReleaseNotesStyle Style of release notes to generate
+---@param version_info table { from: string, to: string } Version range information
+---@return string Generated prompt for AI release notes generation
 function M.create_smart_prompt(commits, style, version_info)
+  -- Input validation
+  if type(commits) ~= "table" then
+    commits = {}
+  end
+
+  if not version_info or type(version_info) ~= "table" or not version_info.from or not version_info.to then
+    version_info = { from = "unknown", to = "unknown" }
+  end
+
   local analysis = M.analyze_commits(commits)
   local guide = M.style_guides[style] or M.style_guides.detailed
 

lua/codecompanion/_extensions/gitcommit/tools/ai_release_notes.lua

@@ -1,6 +1,8 @@
 local prompts = require("codecompanion._extensions.gitcommit.prompts.release_notes")
 local git_utils = require("codecompanion._extensions.gitcommit.git_utils")
+local Command = require("codecompanion._extensions.gitcommit.tools.command")
 
+local CommandExecutor = Command.CommandExecutor
 local shell_quote = git_utils.shell_quote
 
 ---@class CodeCompanion.GitCommit.Tools.AIReleaseNotes: CodeCompanion.Tools.Tool
@@ -51,7 +53,9 @@ Output styles:
 - changelog: Developer-focused changelog format
 - marketing: User-friendly marketing release notes]]
 
--- Helper function to get commit details with diffs
+---@param from_ref string Starting reference (tag or commit hash)
+---@param to_ref string Ending reference (tag or commit hash or HEAD)
+---@return table|nil, string|nil Commits array and error message
 local function get_detailed_commits(from_ref, to_ref)
   -- Git range A..B = commits reachable from B but not from A
   -- This correctly excludes from_ref itself and includes up to to_ref
@@ -63,8 +67,8 @@ local function get_detailed_commits(from_ref, to_ref)
   local format_str = shell_quote("%H||%s||%an||%b" .. separator)
   local commit_cmd = string.format("git log --pretty=format:%s %s", format_str, escaped_range)
 
-  local success, output = pcall(vim.fn.system, commit_cmd)
-  if not success or vim.v.shell_error ~= 0 then
+  local success, output = CommandExecutor.run(commit_cmd)
+  if not success then
     return nil, "Failed to get commit history"
   end
 
@@ -79,12 +83,12 @@ local function get_detailed_commits(from_ref, to_ref)
 
   for _, entry in ipairs(commit_entries) do
     if entry and vim.trim(entry) ~= "" then
-      -- Find the first non-empty line with commit info
+      -- Find first non-empty line with commit info
       local lines = vim.split(entry, "\n")
       local commit_line = nil
       local body_start_idx = 1
 
-      -- Find the line with the commit info (has || separators)
+      -- Find line with commit info (has || separators)
       for i, line in ipairs(lines) do
         if line:match("||") then
           commit_line = line
@@ -145,8 +149,8 @@ AIReleaseNotes.cmds = {
     -- Get tags if not specified
     if not to_tag or not from_tag then
       -- Try to get tags sorted by version
-      local success, tags_output = pcall(vim.fn.system, "git tag --sort=-version:refname")
-      if success and vim.v.shell_error == 0 and tags_output and vim.trim(tags_output) ~= "" then
+      local success, tags_output = CommandExecutor.run("git tag --sort=-version:refname")
+      if success and tags_output and vim.trim(tags_output) ~= "" then
         local tags = {}
         for tag in tags_output:gmatch("[^\r\n]+") do
           local trimmed = vim.trim(tag)
@@ -171,8 +175,8 @@ AIReleaseNotes.cmds = {
           elseif #tags == 1 then
             -- Only one tag, get first commit as starting point
             local first_commit_cmd = "git rev-list --max-parents=0 HEAD"
-            local fc_success, first_commit_output = pcall(vim.fn.system, first_commit_cmd)
-            if fc_success and vim.v.shell_error == 0 then
+            local fc_success, first_commit_output = CommandExecutor.run(first_commit_cmd)
+            if fc_success and first_commit_output and vim.trim(first_commit_output) ~= "" then
               from_tag = vim.trim(first_commit_output):sub(1, 8)
             else
               -- Fallback to 10 commits ago