feat: XDG taskrc config (#2380)

Co-authored-by: Valentin Maerten <maerten.valentin@gmail.com>

taskrc/ast/taskrc.go

@@ -1,8 +1,27 @@
 package ast
 
-import "github.com/Masterminds/semver/v3"
+import (
+	"maps"
+
+	"github.com/Masterminds/semver/v3"
+)
 
 type TaskRC struct {
 	Version     *semver.Version `yaml:"version"`
 	Experiments map[string]int  `yaml:"experiments"`
 }
+
+// Merge combines the current TaskRC with another TaskRC, prioritizing non-nil fields from the other TaskRC.
+func (t *TaskRC) Merge(other *TaskRC) {
+	if other == nil {
+		return
+	}
+	if t.Version == nil && other.Version != nil {
+		t.Version = other.Version
+	}
+	if t.Experiments == nil && other.Experiments != nil {
+		t.Experiments = other.Experiments
+	} else if t.Experiments != nil && other.Experiments != nil {
+		maps.Copy(t.Experiments, other.Experiments)
+	}
+}

taskrc/node.go

@@ -1,10 +1,11 @@
 package taskrc
 
-import "github.com/go-task/task/v3/internal/fsext"
+import (
+	"github.com/go-task/task/v3/internal/fsext"
+)
 
 type Node struct {
 	entrypoint string
-	dir        string
 }
 
 func NewNode(
@@ -12,13 +13,11 @@ func NewNode(
 	dir string,
 ) (*Node, error) {
 	dir = fsext.DefaultDir(entrypoint, dir)
-	var err error
-	entrypoint, dir, err = fsext.Search(entrypoint, dir, defaultTaskRCs)
+	resolvedEntrypoint, err := fsext.SearchPath(dir, defaultTaskRCs)
 	if err != nil {
 		return nil, err
 	}
 	return &Node{
-		entrypoint: entrypoint,
-		dir:        dir,
+		entrypoint: resolvedEntrypoint,
 	}, nil
 }

taskrc/taskrc.go

@@ -1,6 +1,63 @@
 package taskrc
 
+import (
+	"os"
+	"path/filepath"
+	"slices"
+
+	"github.com/go-task/task/v3/internal/fsext"
+	"github.com/go-task/task/v3/taskrc/ast"
+)
+
 var defaultTaskRCs = []string{
 	".taskrc.yml",
 	".taskrc.yaml",
 }
+
+// GetConfig loads and merges local and global Task configuration files
+func GetConfig(dir string) (*ast.TaskRC, error) {
+	var config *ast.TaskRC
+	reader := NewReader()
+
+	// Read the XDG config file
+	if xdgConfigHome := os.Getenv("XDG_CONFIG_HOME"); xdgConfigHome != "" {
+		xdgConfigNode, err := NewNode("", filepath.Join(xdgConfigHome, "task"))
+		if err == nil && xdgConfigNode != nil {
+			config, err = reader.Read(xdgConfigNode)
+			if err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	// Find all the nodes from the given directory up to the users home directory
+	entrypoints, err := fsext.SearchAll("", dir, defaultTaskRCs)
+	if err != nil {
+		return nil, err
+	}
+
+	// Reverse the entrypoints since we want the child files to override parent ones
+	slices.Reverse(entrypoints)
+
+	// Loop over the nodes, and merge them into the main config
+	for _, entrypoint := range entrypoints {
+		node, err := NewNode("", entrypoint)
+		if err != nil {
+			return nil, err
+		}
+		localConfig, err := reader.Read(node)
+		if err != nil {
+			return nil, err
+		}
+		if localConfig == nil {
+			continue
+		}
+		if config == nil {
+			config = localConfig
+			continue
+		}
+		config.Merge(localConfig)
+	}
+
+	return config, nil
+}

taskrc/taskrc_test.go

@@ -0,0 +1,137 @@
+package taskrc
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/go-task/task/v3/taskrc/ast"
+)
+
+const (
+	xdgConfigYAML = `
+experiments:
+  FOO: 1
+  BAR: 1
+  BAZ: 1
+`
+
+	homeConfigYAML = `
+experiments:
+  FOO: 2
+  BAR: 2
+`
+
+	localConfigYAML = `
+experiments:
+  FOO: 3
+`
+)
+
+func setupDirs(t *testing.T) (string, string, string) {
+	t.Helper()
+
+	xdgConfigDir := t.TempDir()
+	xdgTaskConfigDir := filepath.Join(xdgConfigDir, "task")
+	require.NoError(t, os.Mkdir(xdgTaskConfigDir, 0o755))
+
+	homeDir := t.TempDir()
+
+	localDir := filepath.Join(homeDir, "local")
+	require.NoError(t, os.Mkdir(localDir, 0o755))
+
+	t.Setenv("XDG_CONFIG_HOME", xdgConfigDir)
+	t.Setenv("HOME", homeDir)
+
+	return xdgTaskConfigDir, homeDir, localDir
+}
+
+func writeFile(t *testing.T, dir, filename, content string) {
+	t.Helper()
+	err := os.WriteFile(filepath.Join(dir, filename), []byte(content), 0o644)
+	assert.NoError(t, err)
+}
+
+func TestGetConfig_NoConfigFiles(t *testing.T) { //nolint:paralleltest // cannot run in parallel
+	_, _, localDir := setupDirs(t)
+
+	cfg, err := GetConfig(localDir)
+	assert.NoError(t, err)
+	assert.Nil(t, cfg)
+}
+
+func TestGetConfig_OnlyXDG(t *testing.T) { //nolint:paralleltest // cannot run in parallel
+	xdgDir, _, localDir := setupDirs(t)
+
+	writeFile(t, xdgDir, ".taskrc.yml", xdgConfigYAML)
+
+	cfg, err := GetConfig(localDir)
+	assert.NoError(t, err)
+	assert.Equal(t, &ast.TaskRC{
+		Version: nil,
+		Experiments: map[string]int{
+			"FOO": 1,
+			"BAR": 1,
+			"BAZ": 1,
+		},
+	}, cfg)
+}
+
+func TestGetConfig_OnlyHome(t *testing.T) { //nolint:paralleltest // cannot run in parallel
+	_, homeDir, localDir := setupDirs(t)
+
+	writeFile(t, homeDir, ".taskrc.yml", homeConfigYAML)
+
+	cfg, err := GetConfig(localDir)
+	assert.NoError(t, err)
+	assert.Equal(t, &ast.TaskRC{
+		Version: nil,
+		Experiments: map[string]int{
+			"FOO": 2,
+			"BAR": 2,
+		},
+	}, cfg)
+}
+
+func TestGetConfig_OnlyLocal(t *testing.T) { //nolint:paralleltest // cannot run in parallel
+	_, _, localDir := setupDirs(t)
+
+	writeFile(t, localDir, ".taskrc.yml", localConfigYAML)
+
+	cfg, err := GetConfig(localDir)
+	assert.NoError(t, err)
+	assert.Equal(t, &ast.TaskRC{
+		Version: nil,
+		Experiments: map[string]int{
+			"FOO": 3,
+		},
+	}, cfg)
+}
+
+func TestGetConfig_All(t *testing.T) { //nolint:paralleltest // cannot run in parallel
+	xdgConfigDir, homeDir, localDir := setupDirs(t)
+
+	// Write local config
+	writeFile(t, localDir, ".taskrc.yml", localConfigYAML)
+
+	// Write home config
+	writeFile(t, homeDir, ".taskrc.yml", homeConfigYAML)
+
+	// Write XDG config
+	writeFile(t, xdgConfigDir, ".taskrc.yml", xdgConfigYAML)
+
+	cfg, err := GetConfig(localDir)
+	assert.NoError(t, err)
+	assert.NotNil(t, cfg)
+	assert.Equal(t, &ast.TaskRC{
+		Version: nil,
+		Experiments: map[string]int{
+			"FOO": 3,
+			"BAR": 2,
+			"BAZ": 1,
+		},
+	}, cfg)
+}