From abb19dfbf8d1e0db74f4dcd90755c5e52320f88f Mon Sep 17 00:00:00 2001
From: Andrey Nering <andrey.nering@gmail.com>
Date: Sat, 30 Sep 2017 14:56:35 -0300
Subject: [PATCH] print logs to stderr instead of stdout

also, don't print up-to-date status when the --silent flag was given

closes #68
---
 help.go      |  2 +-
 log.go       | 26 ++++++++++++++++----------
 task.go      |  8 +++++---
 variables.go |  2 +-
 watch.go     | 12 ++++++------
 5 files changed, 29 insertions(+), 21 deletions(-)

diff --git a/help.go b/help.go
index c5919bc9..9681d90d 100644
--- a/help.go
+++ b/help.go
@@ -12,7 +12,7 @@ func (e *Executor) PrintTasksHelp() {
 	if len(tasks) == 0 {
 		return
 	}
-	e.println("Available tasks for this project:")
+	e.outf("Available tasks for this project:")
 
 	// Format in tab-separated columns with a tab stop of 8.
 	w := tabwriter.NewWriter(e.Stdout, 0, 8, 0, '\t', 0)
diff --git a/log.go b/log.go
index e8b070a1..fc168130 100644
--- a/log.go
+++ b/log.go
@@ -4,22 +4,28 @@ import (
 	"fmt"
 )
 
-func (e *Executor) println(args ...interface{}) {
-	fmt.Fprintln(e.Stdout, args...)
+func (e *Executor) outf(s string, args ...interface{}) {
+	if len(args) == 0 {
+		s, args = "%s", []interface{}{s}
+	}
+	fmt.Fprintf(e.Stdout, s+"\n", args...)
 }
 
-func (e *Executor) printfln(format string, args ...interface{}) {
-	fmt.Fprintf(e.Stdout, format+"\n", args...)
-}
-
-func (e *Executor) verbosePrintln(args ...interface{}) {
+func (e *Executor) verboseOutf(s string, args ...interface{}) {
 	if e.Verbose {
-		e.println(args...)
+		e.outf(s, args...)
 	}
 }
 
-func (e *Executor) verbosePrintfln(format string, args ...interface{}) {
+func (e *Executor) errf(s string, args ...interface{}) {
+	if len(args) == 0 {
+		s, args = "%s", []interface{}{s}
+	}
+	fmt.Fprintf(e.Stderr, s+"\n", args...)
+}
+
+func (e *Executor) verboseErrf(s string, args ...interface{}) {
 	if e.Verbose {
-		e.printfln(format, args...)
+		e.errf(s, args...)
 	}
 }
diff --git a/task.go b/task.go
index febf1886..0446737c 100644
--- a/task.go
+++ b/task.go
@@ -126,7 +126,9 @@ func (e *Executor) RunTask(ctx context.Context, call Call) error {
 			return err
 		}
 		if upToDate {
-			e.printfln(`task: Task "%s" is up to date`, t.Task)
+			if !e.Silent {
+				e.errf(`task: Task "%s" is up to date`, t.Task)
+			}
 			return nil
 		}
 	}
@@ -134,7 +136,7 @@ func (e *Executor) RunTask(ctx context.Context, call Call) error {
 	for i := range t.Cmds {
 		if err := e.runCommand(ctx, t, call, i); err != nil {
 			if err2 := t.statusOnError(); err2 != nil {
-				e.verbosePrintfln("task: error cleaning status on error: %v", err2)
+				e.verboseErrf("task: error cleaning status on error: %v", err2)
 			}
 			return &taskRunError{t.Task, err}
 		}
@@ -164,7 +166,7 @@ func (e *Executor) runCommand(ctx context.Context, t *Task, call Call, i int) er
 	}
 
 	if e.Verbose || (!cmd.Silent && !t.Silent && !e.Silent) {
-		e.println(cmd.Cmd)
+		e.errf(cmd.Cmd)
 	}
 
 	return execext.RunCommand(&execext.RunCommandOptions{
diff --git a/variables.go b/variables.go
index 11840b67..0ca38d16 100644
--- a/variables.go
+++ b/variables.go
@@ -189,7 +189,7 @@ func (e *Executor) handleShVar(v Var) (string, error) {
 	result := strings.TrimSuffix(stdout.String(), "\n")
 
 	e.dynamicCache[v.Sh] = result
-	e.verbosePrintfln(`task: dynamic variable: '%s' result: '%s'`, v.Sh, result)
+	e.verboseErrf(`task: dynamic variable: '%s' result: '%s'`, v.Sh, result)
 
 	return result, nil
 }
diff --git a/watch.go b/watch.go
index 24050882..68dc569e 100644
--- a/watch.go
+++ b/watch.go
@@ -20,14 +20,14 @@ func (e *Executor) watchTasks(calls ...Call) error {
 	for i, c := range calls {
 		tasks[i] = c.Task
 	}
-	e.printfln("task: Started watching for tasks: %s", strings.Join(tasks, ", "))
+	e.errf("task: Started watching for tasks: %s", strings.Join(tasks, ", "))
 
 	ctx, cancel := context.WithCancel(context.Background())
 	for _, c := range calls {
 		c := c
 		go func() {
 			if err := e.RunTask(ctx, c); err != nil && !isContextError(err) {
-				e.println(err)
+				e.errf("%v", err)
 			}
 		}()
 	}
@@ -43,7 +43,7 @@ func (e *Executor) watchTasks(calls ...Call) error {
 		for {
 			select {
 			case event := <-w.Event:
-				e.verbosePrintfln("task: received watch event: %v", event)
+				e.verboseErrf("task: received watch event: %v", event)
 
 				cancel()
 				ctx, cancel = context.WithCancel(context.Background())
@@ -51,7 +51,7 @@ func (e *Executor) watchTasks(calls ...Call) error {
 					c := c
 					go func() {
 						if err := e.RunTask(ctx, c); err != nil && !isContextError(err) {
-							e.println(err)
+							e.errf("%v", err)
 						}
 					}()
 				}
@@ -62,7 +62,7 @@ func (e *Executor) watchTasks(calls ...Call) error {
 						w.TriggerEvent(watcher.Remove, nil)
 					}()
 				default:
-					e.println(err)
+					e.errf("%v", err)
 				}
 			case <-w.Closed:
 				return
@@ -74,7 +74,7 @@ func (e *Executor) watchTasks(calls ...Call) error {
 		// re-register each second because we can have new files
 		for {
 			if err := e.registerWatchedFiles(w, tasks); err != nil {
-				e.println(err)
+				e.errf("%v", err)
 			}
 			time.Sleep(time.Second)
 		}