refactor: remove rootDir param, auto-detect .git as boundary

Walk up from task dir to find .git instead of threading rootDir through
Globs, checkers, and itemsFromFor. Gitignore rules are discarded if no
.git is found, matching ripgrep's require_git behavior. This keeps the
Globs signature clean and makes the future .taskignore integration
straightforward (loaded at setup like .taskrc, separate boundary).

internal/fingerprint/gitignore_test.go

@@ -19,10 +19,7 @@ func initGitRepo(t *testing.T, dir string) {
 func TestGlobsWithGitignore(t *testing.T) {
 	t.Parallel()
 
-	dir, err := os.MkdirTemp("", "task-gitignore-test-*")
-	require.NoError(t, err)
-	t.Cleanup(func() { os.RemoveAll(dir) })
-
+	dir := t.TempDir()
 	initGitRepo(t, dir)
 
 	require.NoError(t, os.WriteFile(filepath.Join(dir, "included.txt"), []byte("included"), 0o644))
@@ -70,10 +67,7 @@ func TestGlobsWithGitignore(t *testing.T) {
 func TestGlobsWithGitignoreNested(t *testing.T) {
 	t.Parallel()
 
-	dir, err := os.MkdirTemp("", "task-gitignore-nested-*")
-	require.NoError(t, err)
-	t.Cleanup(func() { os.RemoveAll(dir) })
-
+	dir := t.TempDir()
 	initGitRepo(t, dir)
 
 	subDir := filepath.Join(dir, "sub")
@@ -82,9 +76,7 @@ func TestGlobsWithGitignoreNested(t *testing.T) {
 	require.NoError(t, os.WriteFile(filepath.Join(subDir, "keep.txt"), []byte("keep"), 0o644))
 	require.NoError(t, os.WriteFile(filepath.Join(subDir, "build.out"), []byte("build"), 0o644))
 
-	// Root .gitignore ignores *.log
 	require.NoError(t, os.WriteFile(filepath.Join(dir, ".gitignore"), []byte("*.log\n"), 0o644))
-	// Nested .gitignore ignores *.out
 	require.NoError(t, os.WriteFile(filepath.Join(subDir, ".gitignore"), []byte("*.out\n"), 0o644))
 
 	globs := []*ast.Glob{
@@ -102,7 +94,9 @@ func TestGlobsWithGitignoreNested(t *testing.T) {
 func TestGlobsWithGitignoreNoRepo(t *testing.T) {
 	t.Parallel()
 
-	dir, err := os.MkdirTemp("", "task-gitignore-norepo-*")
+	// Cannot use t.TempDir() here because it creates a dir inside the
+	// go-task repo which has a .git parent, defeating the "no repo" test.
+	dir, err := os.MkdirTemp("", "task-gitignore-norepo-*") //nolint:usetesting
 	require.NoError(t, err)
 	t.Cleanup(func() { os.RemoveAll(dir) })
 

taskfile/ast/task.go

@@ -156,7 +156,7 @@ func (t *Task) UnmarshalYAML(node *yaml.Node) error {
 			Internal      bool
 			Method        string
 			Prefix        string
-			IgnoreError   bool `yaml:"ignore_error"`
+			IgnoreError   bool  `yaml:"ignore_error"`
 			Gitignore     *bool `yaml:"gitignore,omitempty"`
 			Run           string
 			Platforms     []*Platform

taskfile/ast/taskfile.go

@@ -20,16 +20,16 @@ var ErrIncludedTaskfilesCantHaveDotenvs = errors.New("task: Included Taskfiles c
 
 // Taskfile is the abstract syntax tree for a Taskfile
 type Taskfile struct {
-	Location string
-	Version  *semver.Version
-	Output   Output
-	Method   string
-	Includes *Includes
-	Set      []string
-	Shopt    []string
-	Vars     *Vars
-	Env      *Vars
-	Tasks    *Tasks
+	Location  string
+	Version   *semver.Version
+	Output    Output
+	Method    string
+	Includes  *Includes
+	Set       []string
+	Shopt     []string
+	Vars      *Vars
+	Env       *Vars
+	Tasks     *Tasks
 	Silent    bool
 	Dotenv    []string
 	Run       string
@@ -77,18 +77,18 @@ func (tf *Taskfile) UnmarshalYAML(node *yaml.Node) error {
 	switch node.Kind {
 	case yaml.MappingNode:
 		var taskfile struct {
-			Version  *semver.Version
-			Output   Output
-			Method   string
-			Includes *Includes
-			Set      []string
-			Shopt    []string
-			Vars     *Vars
-			Env      *Vars
-			Tasks    *Tasks
-			Silent   bool
-			Dotenv   []string
-			Run      string
+			Version   *semver.Version
+			Output    Output
+			Method    string
+			Includes  *Includes
+			Set       []string
+			Shopt     []string
+			Vars      *Vars
+			Env       *Vars
+			Tasks     *Tasks
+			Silent    bool
+			Dotenv    []string
+			Run       string
 			Interval  time.Duration
 			Gitignore bool
 		}