feat: recursive config search (#2166)

* refactor: experiments flags

* refactor: args.Parse

* feat: recursive search for taskrc files

* feat: consolidate some code into new fsext package

* feat: add tests for search and default dir

* fix: linting issues

taskrc/ast/taskrc.go

@@ -0,0 +1,8 @@
+package ast
+
+import "github.com/Masterminds/semver/v3"
+
+type TaskRC struct {
+	Version     *semver.Version `yaml:"version"`
+	Experiments map[string]int  `yaml:"experiments"`
+}

taskrc/node.go

@@ -0,0 +1,24 @@
+package taskrc
+
+import "github.com/go-task/task/v3/internal/fsext"
+
+type Node struct {
+	entrypoint string
+	dir        string
+}
+
+func NewNode(
+	entrypoint string,
+	dir string,
+) (*Node, error) {
+	dir = fsext.DefaultDir(entrypoint, dir)
+	var err error
+	entrypoint, dir, err = fsext.Search(entrypoint, dir, defaultTaskRCs)
+	if err != nil {
+		return nil, err
+	}
+	return &Node{
+		entrypoint: entrypoint,
+		dir:        dir,
+	}, nil
+}

taskrc/reader.go

@@ -0,0 +1,79 @@
+package taskrc
+
+import (
+	"os"
+
+	"gopkg.in/yaml.v3"
+
+	"github.com/go-task/task/v3/taskrc/ast"
+)
+
+type (
+	// DebugFunc is a function that can be called to log debug messages.
+	DebugFunc func(string)
+	// A ReaderOption is any type that can apply a configuration to a [Reader].
+	ReaderOption interface {
+		ApplyToReader(*Reader)
+	}
+	// A Reader will recursively read Taskfiles from a given [Node] and build a
+	// [ast.TaskRC] from them.
+	Reader struct {
+		debugFunc DebugFunc
+	}
+)
+
+// NewReader constructs a new Taskfile [Reader] using the given Node and
+// options.
+func NewReader(opts ...ReaderOption) *Reader {
+	r := &Reader{
+		debugFunc: nil,
+	}
+	r.Options(opts...)
+	return r
+}
+
+// Options loops through the given [ReaderOption] functions and applies them to
+// the [Reader].
+func (r *Reader) Options(opts ...ReaderOption) {
+	for _, opt := range opts {
+		opt.ApplyToReader(r)
+	}
+}
+
+// WithDebugFunc sets the debug function to be used by the [Reader]. If set,
+// this function will be called with debug messages. This can be useful if the
+// caller wants to log debug messages from the [Reader]. By default, no debug
+// function is set and the logs are not written.
+func WithDebugFunc(debugFunc DebugFunc) ReaderOption {
+	return &debugFuncOption{debugFunc: debugFunc}
+}
+
+type debugFuncOption struct {
+	debugFunc DebugFunc
+}
+
+func (o *debugFuncOption) ApplyToReader(r *Reader) {
+	r.debugFunc = o.debugFunc
+}
+
+// Read will read the Task config defined by the [Reader]'s [Node].
+func (r *Reader) Read(node *Node) (*ast.TaskRC, error) {
+	var config ast.TaskRC
+
+	if node == nil {
+		return nil, os.ErrInvalid
+	}
+
+	// Read the file
+	b, err := os.ReadFile(node.entrypoint)
+	if err != nil {
+		return nil, err
+	}
+
+	// Parse the content
+	if err := yaml.Unmarshal(b, &config); err != nil {
+		return nil, err
+	}
+
+	return &config, nil
+}

taskrc/taskrc.go

@@ -0,0 +1,6 @@
+package taskrc
+
+var defaultTaskRCs = []string{
+	".taskrc.yml",
+	".taskrc.yaml",
+}