Merge pull request #258 from ericfialkowski/helpers

Added WithStdout and WithStderr helpers

icmd/command.go

@@ -195,6 +195,7 @@ type Cmd struct {
 	Timeout    time.Duration
 	Stdin      io.Reader
 	Stdout     io.Writer
+	Stderr     io.Writer
 	Dir        string
 	Env        []string
 	ExtraFiles []*os.File
@@ -252,7 +253,11 @@ func buildCmd(cmd Cmd) *Result {
 	} else {
 		execCmd.Stdout = outBuffer
 	}
-	execCmd.Stderr = errBuffer
+	if cmd.Stderr != nil {
+		execCmd.Stderr = io.MultiWriter(errBuffer, cmd.Stderr)
+	} else {
+		execCmd.Stderr = errBuffer
+	}
 	execCmd.ExtraFiles = cmd.ExtraFiles
 
 	return &Result{

icmd/ops.go

@@ -38,6 +38,20 @@ func WithStdin(r io.Reader) CmdOp {
 	}
 }
 
+// WithStdout sets the standard output of the command to the specified writer
+func WithStdout(w io.Writer) CmdOp {
+	return func(c *Cmd) {
+		c.Stdout = w
+	}
+}
+
+// WithStderr sets the standard error of the command to the specified writer
+func WithStderr(w io.Writer) CmdOp {
+	return func(c *Cmd) {
+		c.Stderr = w
+	}
+}
+
 // WithExtraFile adds a file descriptor to the command
 func WithExtraFile(f *os.File) CmdOp {
 	return func(c *Cmd) {