1 files changed, 321 insertions, 2 deletions
diff --git a/lua/99/test/files_spec.lua b/lua/99/test/files_spec.lua
index e033abe..53d9458 100644
--- a/lua/99/test/files_spec.lua
+++ b/lua/99/test/files_spec.lua
@@ -33,13 +33,11 @@ describe("files", function()
       paths[f.path] = f
     end
 
-    -- known fixture files must be present
     assert.is_not_nil(paths["scratch/refresh.lua"])
     assert.is_not_nil(paths["scratch/test.ts"])
     eq("refresh.lua", paths["scratch/refresh.lua"].name)
     eq("test.ts", paths["scratch/test.ts"].name)
 
-    -- .git must be excluded
     for path, _ in pairs(paths) do
       assert.is_nil(
         path:match("^%.git/"),
@@ -199,3 +197,324 @@ describe("files", function()
     )
   end)
 end)
+
+describe("files git integration", function()
+  -- Mock storage
+  local _mocks = {
+    system_output = "",
+    system_exit = 0,
+    stat_type = nil,
+    stat_exists = false,
+    orig_system = nil,
+    orig_stat = nil,
+    orig_shell_error = nil,
+    system_calls = {},
+  }
+
+  before_each(function()
+    _mocks.orig_system = vim.fn.system
+    _mocks.orig_stat = vim.uv.fs_stat
+
+    _mocks.system_output = ""
+    _mocks.system_exit = 0
+    _mocks.stat_type = nil
+    _mocks.stat_exists = false
+    _mocks.system_calls = {}
+
+    vim.fn.system = function(cmd)
+      table.insert(_mocks.system_calls, cmd)
+
+      pcall(function()
+        rawset(vim.v, "shell_error", _mocks.system_exit)
+      end)
+      return _mocks.system_output
+    end
+
+    vim.uv.fs_stat = function(_path)
+      if _mocks.stat_exists then
+        return { type = _mocks.stat_type }
+      end
+      return nil
+    end
+
+    Files.set_project_root("/test/repo")
+  end)
+
+  after_each(function()
+    vim.fn.system = _mocks.orig_system
+    vim.uv.fs_stat = _mocks.orig_stat
+
+    pcall(function()
+      rawset(vim.v, "shell_error", 0)
+    end)
+    Files.set_project_root("")
+  end)
+
+  it(
+    "detects git repo with .git directory and uses git-based discovery",
+    function()
+      _mocks.stat_exists = true
+      _mocks.stat_type = "directory"
+      _mocks.system_output = "README.md\n"
+      _mocks.system_exit = 0
+
+      local files = Files.discover_files()
+
+      assert.is_true(
+        #_mocks.system_calls > 0,
+        "git command should have been called"
+      )
+      local git_called = false
+      for _, cmd in ipairs(_mocks.system_calls) do
+        if cmd:match("git.*ls%-files") then
+          git_called = true
+          break
+        end
+      end
+      assert.is_true(git_called, "git ls-files should have been executed")
+
+      assert.is_true(#files > 0, "should return files from git")
+      eq("README.md", files[1].path)
+    end
+  )
+
+  it(
+    "detects git repo with .git file (worktree) and uses git-based discovery",
+    function()
+      _mocks.stat_exists = true
+      _mocks.stat_type = "file"
+      _mocks.system_output = "src/main.lua\ntest/file.lua\n"
+      _mocks.system_exit = 0
+
+      local files = Files.discover_files()
+
+      assert.is_true(
+        #_mocks.system_calls > 0,
+        "git command should have been called for worktree"
+      )
+      local git_called = false
+      for _, cmd in ipairs(_mocks.system_calls) do
+        if cmd:match("git.*ls%-files") then
+          git_called = true
+          break
+        end
+      end
+      assert.is_true(git_called, "should use git for worktree .git file")
+
+      assert.are.equal(2, #files)
+      eq("src/main.lua", files[1].path)
+      eq("test/file.lua", files[2].path)
+    end
+  )
+
+  it("returns files when git command succeeds", function()
+    _mocks.stat_exists = true
+    _mocks.stat_type = "directory"
+    _mocks.system_output = "README.md\nsrc/init.lua\nsrc/utils.lua\n"
+    _mocks.system_exit = 0
+
+    local files = Files.discover_files()
+
+    assert.are.equal(3, #files)
+    eq("README.md", files[1].path)
+    eq("src/init.lua", files[2].path)
+    eq("src/utils.lua", files[3].path)
+
+    for _, f in ipairs(files) do
+      assert.is_not_nil(f.path, "file should have path")
+      assert.is_not_nil(f.name, "file should have name")
+      assert.is_not_nil(f.absolute_path, "file should have absolute_path")
+    end
+  end)
+
+  it("returns empty table (not nil) for empty repo", function()
+    _mocks.stat_exists = true
+    _mocks.stat_type = "directory"
+    _mocks.system_output = ""
+    _mocks.system_exit = 0
+
+    local files = Files.discover_files()
+
+    assert.is_not_nil(files, "should return table, not nil")
+    assert.are.equal(0, #files, "should return empty table for empty repo")
+
+    for _, cmd in ipairs(_mocks.system_calls) do
+      assert.is_true(
+        cmd:match("git") ~= nil,
+        "should only call git, not fs commands"
+      )
+    end
+  end)
+
+  it("returns nil on git command failure", function()
+    _mocks.stat_exists = true
+    _mocks.stat_type = "directory"
+    _mocks.system_output = "fatal: not a git repository"
+    _mocks.system_exit = 128 -- Git failure
+
+    local orig_scandir = vim.uv.fs_scandir
+    vim.uv.fs_scandir = function(_dir)
+      return nil -- Empty directory
+    end
+
+    local files = Files.discover_files()
+
+    vim.uv.fs_scandir = orig_scandir
+
+    local git_failed = false
+    for _, cmd in ipairs(_mocks.system_calls) do
+      if cmd:match("git") and vim.v.shell_error ~= 0 then
+        git_failed = true
+        break
+      end
+    end
+    assert.is_true(git_failed, "git should have been called and failed")
+  end)
+
+  it("applies manual excludes on top of git output", function()
+    _mocks.stat_exists = true
+    _mocks.stat_type = "directory"
+    _mocks.system_output =
+      "README.md\n.env\n.env.local\nnode_modules/package.json\nsrc/main.lua\n"
+    _mocks.system_exit = 0
+
+    Files.setup({
+      enabled = true,
+      exclude = { ".env", ".env.*", "node_modules" },
+    }, {})
+
+    local files = Files.discover_files()
+
+    assert.are.equal(2, #files)
+    eq("README.md", files[1].path)
+    eq("src/main.lua", files[2].path)
+
+    for _, f in ipairs(files) do
+      assert.is_nil(f.path:match("%.env"), ".env files should be excluded")
+      assert.is_nil(
+        f.path:match("node_modules"),
+        "node_modules should be excluded"
+      )
+    end
+  end)
+
+  it(
+    "excludes files by filename (not just path) consistent with fs scanner",
+    function()
+      _mocks.stat_exists = true
+      _mocks.stat_type = "directory"
+      _mocks.system_output = "README.md\nsrc/builder.js\nsrc/build/config.lua\n"
+      _mocks.system_exit = 0
+
+      Files.setup({
+        enabled = true,
+        exclude = { "build" },
+      }, {})
+
+      local files = Files.discover_files()
+
+      assert.are.equal(1, #files)
+      eq("README.md", files[1].path)
+
+      for _, f in ipairs(files) do
+        assert.is_nil(
+          f.name:match("^build"),
+          "files starting with 'build' should be excluded"
+        )
+      end
+    end
+  )
+
+  it("uses --deduplicate flag to handle merge conflict duplicates", function()
+    _mocks.stat_exists = true
+    _mocks.stat_type = "directory"
+
+    _mocks.system_output = "README.md\nREADME.md\nREADME.md\n"
+    _mocks.system_exit = 0
+
+    local files = Files.discover_files()
+
+    local has_deduplicate = false
+    for _, cmd in ipairs(_mocks.system_calls) do
+      if cmd:match("%-%-deduplicate") then
+        has_deduplicate = true
+        break
+      end
+    end
+    assert.is_true(
+      has_deduplicate,
+      "git command should include --deduplicate flag"
+    )
+  end)
+
+  it("uses git-based discovery in git repo", function()
+    _mocks.stat_exists = true
+    _mocks.stat_type = "directory"
+    _mocks.system_output = "tracked.txt\n"
+    _mocks.system_exit = 0
+
+    Files.discover_files()
+
+    local git_called = false
+    for _, cmd in ipairs(_mocks.system_calls) do
+      if cmd:match("git") then
+        git_called = true
+        break
+      end
+    end
+    assert.is_true(git_called, "should use git ls-files in git repo")
+  end)
+
+  it("falls back to filesystem when not in git repo", function()
+    _mocks.stat_exists = false
+    local orig_scandir = vim.uv.fs_scandir
+    local fs_called = false
+    vim.uv.fs_scandir = function(_dir)
+      fs_called = true
+      return nil -- Empty
+    end
+
+    Files.discover_files()
+
+    vim.uv.fs_scandir = orig_scandir
+
+    for _, cmd in ipairs(_mocks.system_calls) do
+      assert.is_nil(
+        cmd:match("git"),
+        "git should not be called in non-git repo"
+      )
+    end
+
+    assert.is_true(fs_called, "filesystem fallback should be used")
+  end)
+
+  it("returns cached files on subsequent calls", function()
+    _mocks.stat_exists = true
+    _mocks.stat_type = "directory"
+    _mocks.system_output = "file.txt\n"
+    _mocks.system_exit = 0
+
+    local first = Files.get_files()
+    local first_call_count = #_mocks.system_calls
+
+    local second = Files.get_files()
+    local second_call_count = #_mocks.system_calls
+
+    eq(first, second)
+
+    assert.are.equal(
+      first_call_count,
+      second_call_count,
+      "should not re-scan, use cache"
+    )
+  end)
+
+  it("handles empty root gracefully", function()
+    Files.set_project_root("")
+
+    local files = Files.discover_files()
+
+    assert.is_not_nil(files, "should return table")
+    assert.are.equal(0, #files, "should return empty for empty root")
+  end)
+end)