Add "output" option to Taskfile to control how stuff are printed to stdout/stderr

First step for #104

internal/output/group.go

@@ -0,0 +1,26 @@
+package output
+
+import (
+	"bytes"
+	"io"
+)
+
+type Group struct{}
+
+func (Group) WrapWriter(w io.Writer) io.WriteCloser {
+	return &groupWriter{writer: w}
+}
+
+type groupWriter struct {
+	writer io.Writer
+	buff   bytes.Buffer
+}
+
+func (gw *groupWriter) Write(p []byte) (int, error) {
+	return gw.buff.Write(p)
+}
+
+func (gw *groupWriter) Close() error {
+	_, err := io.Copy(gw.writer, &gw.buff)
+	return err
+}

internal/output/interleaved.go

@@ -0,0 +1,23 @@
+package output
+
+import (
+	"io"
+)
+
+type Interleaved struct{}
+
+func (Interleaved) WrapWriter(w io.Writer) io.WriteCloser {
+	return nopWriterCloser{w: w}
+}
+
+type nopWriterCloser struct {
+	w io.Writer
+}
+
+func (wc nopWriterCloser) Write(p []byte) (int, error) {
+	return wc.w.Write(p)
+}
+
+func (wc nopWriterCloser) Close() error {
+	return nil
+}

internal/output/output.go

@@ -0,0 +1,9 @@
+package output
+
+import (
+	"io"
+)
+
+type Output interface {
+	WrapWriter(io.Writer) io.WriteCloser
+}

task.go

@@ -12,6 +12,7 @@ import (
 	compilerv2 "github.com/go-task/task/internal/compiler/v2"
 	"github.com/go-task/task/internal/execext"
 	"github.com/go-task/task/internal/logger"
+	"github.com/go-task/task/internal/output"
 	"github.com/go-task/task/internal/taskfile"
 	"github.com/go-task/task/internal/taskfile/version"
 
@@ -44,6 +45,7 @@ type Executor struct {
 
 	Logger   *logger.Logger
 	Compiler compiler.Compiler
+	Output   output.Output
 
 	taskvars taskfile.Vars
 
@@ -119,9 +121,18 @@ func (e *Executor) Setup() error {
 	case version.IsV22(v):
 		return fmt.Errorf(`task: Taskfile versions greater than v2.1 not implemented in the version of Task`)
 	}
+
 	if !version.IsV21(v) && e.Taskfile.Output != "" {
 		return fmt.Errorf(`task: Taskfile option "output" is only available starting on Taskfile version v2.1`)
 	}
+	switch e.Taskfile.Output {
+	case "", "interleaved":
+		e.Output = output.Interleaved{}
+	case "group":
+		e.Output = output.Group{}
+	default:
+		return fmt.Errorf(`task: output option "%s" not recognized`, e.Taskfile.Output)
+	}
 
 	e.taskCallCount = make(map[string]*int32, len(e.Taskfile.Tasks))
 	for k := range e.Taskfile.Tasks {
@@ -193,14 +204,19 @@ func (e *Executor) runCommand(ctx context.Context, t *taskfile.Task, call taskfi
 		e.Logger.Errf(cmd.Cmd)
 	}
 
+	stdOut := e.Output.WrapWriter(e.Stdout)
+	stdErr := e.Output.WrapWriter(e.Stderr)
+	defer stdOut.Close()
+	defer stdErr.Close()
+
 	return execext.RunCommand(&execext.RunCommandOptions{
 		Context: ctx,
 		Command: cmd.Cmd,
 		Dir:     t.Dir,
 		Env:     getEnviron(t),
 		Stdin:   e.Stdin,
-		Stdout:  e.Stdout,
+		Stdout:  stdOut,
-		Stderr:  e.Stderr,
+		Stderr:  stdErr,
 	})
 }