ensure error respones remain the same, and ensure that deadline context trumps timeout value

Author: dylanhitt

command.go

@@ -203,8 +203,10 @@ func (c *Command) Execute() error {
 	cmd.Stderr = c.StderrWriter
 	cmd.Dir = c.WorkingDir
 
-	// Create timer only if timeout was set > 0
-	if c.Timeout != 0 {
+	// Create timer only if timeout was set > 0 and context does
+	// not have a deadline
+	_, hasDeadline := c.ctx.Deadline()
+	if c.Timeout != 0 && !hasDeadline {
 		ctx, cancel := context.WithTimeout(c.ctx, c.Timeout)
 		defer cancel()
 		c.ctx = ctx
@@ -228,12 +230,16 @@ func (c *Command) Execute() error {
 		if err := cmd.Process.Kill(); err != nil {
 			return fmt.Errorf("Timeout occurred and can not kill process with pid %v", cmd.Process.Pid)
 		}
-		return fmt.Errorf("Command timed out after %v", c.Timeout)
+		if c.Timeout != 0 && !hasDeadline {
+			return fmt.Errorf("Command timed out after %v", c.Timeout)
+		}
+		return c.ctx.Err()
 	case err := <-done:
 		if err != nil {
 			c.getExitCode(err)
 		}
 	}
+
 	c.executed = true
 	return nil
 }

go.sum

@@ -5,6 +5,7 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=