Unambiguous return values. Fixes #18

Author: brandonbloom

panicwrap.go

@@ -78,7 +78,7 @@ type WrapConfig struct {
 // BasicWrap calls Wrap with the given handler function, using defaults
 // for everything else. See Wrap and WrapConfig for more information on
 // functionality and return values.
-func BasicWrap(f HandlerFunc) (int, error) {
+func BasicWrap(f HandlerFunc) (done bool, statusCode int, err error) {
 	return Wrap(&WrapConfig{
 		Handler: f,
 	})
@@ -87,7 +87,7 @@ func BasicWrap(f HandlerFunc) (int, error) {
 // Wrap wraps the current executable in a handler to catch panics. It
 // returns an error if there was an error during the wrapping process.
 // If the error is nil, then the int result indicates the exit status of the
-// child process. If the exit status is -1, then this is the child process,
+// child process. If the done flag is false, then this is the child process,
 // and execution should continue as normal. Otherwise, this is the parent
 // process and the child successfully ran already, and you should exit the
 // process with the returned exit status.
@@ -97,9 +97,9 @@ func BasicWrap(f HandlerFunc) (int, error) {
 //
 // Once this is called, the given WrapConfig shouldn't be modified or used
 // any further.
-func Wrap(c *WrapConfig) (int, error) {
+func Wrap(c *WrapConfig) (done bool, statusCode int, err error) {
 	if c.Handler == nil {
-		return -1, errors.New("Handler must be set")
+		return false, -1, errors.New("Handler must be set")
 	}
 
 	if c.DetectDuration == 0 {
@@ -112,13 +112,13 @@ func Wrap(c *WrapConfig) (int, error) {
 
 	// If we're already wrapped, exit out.
 	if Wrapped(c) {
-		return -1, nil
+		return false, -1, nil
 	}
 
 	// Get the path to our current executable
 	exePath, err := os.Executable()
 	if err != nil {
-		return -1, err
+		return false, -1, err
 	}
 
 	// Pipe the stderr so we can read all the data as we look for panics
@@ -165,7 +165,7 @@ func Wrap(c *WrapConfig) (int, error) {
 	}
 
 	if err := cmd.Start(); err != nil {
-		return 1, err
+		return true, 1, err
 	}
 
 	// Listen to signals and capture them forever. We allow the child
@@ -197,7 +197,7 @@ func Wrap(c *WrapConfig) (int, error) {
 		exitErr, ok := err.(*exec.ExitError)
 		if !ok {
 			// This is some other kind of subprocessing error.
-			return 1, err
+			return true, 1, err
 		}
 
 		exitStatus := 1
@@ -218,10 +218,10 @@ func Wrap(c *WrapConfig) (int, error) {
 			c.Handler(panicTxt)
 		}
 
-		return exitStatus, nil
+		return true, exitStatus, nil
 	}
 
-	return 0, nil
+	return true, 0, nil
 }
 
 // Wrapped checks if we're already wrapped according to the configuration

panicwrap_test.go

@@ -60,13 +60,13 @@ func TestHelperProcess(*testing.T) {
 	cmd, args := args[0], args[1:]
 	switch cmd {
 	case "no-panic-ordered-output":
-		exitStatus, err := BasicWrap(panicHandler)
+		done, exitStatus, err := BasicWrap(panicHandler)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "wrap error: %s", err)
 			os.Exit(1)
 		}
 
-		if exitStatus < 0 {
+		if !done {
 			for i := 0; i < 1000; i++ {
 				os.Stdout.Write([]byte("a"))
 				os.Stderr.Write([]byte("b"))
@@ -80,14 +80,14 @@ func TestHelperProcess(*testing.T) {
 		fmt.Fprint(os.Stderr, "stderr out")
 		os.Exit(0)
 	case "panic-boundary":
-		exitStatus, err := BasicWrap(panicHandler)
+		done, exitStatus, err := BasicWrap(panicHandler)
 
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "wrap error: %s", err)
 			os.Exit(1)
 		}
 
-		if exitStatus < 0 {
+		if !done {
 			// Simulate a panic but on two boundaries...
 			fmt.Fprint(os.Stderr, "pan")
 			os.Stderr.Sync()
@@ -98,14 +98,14 @@ func TestHelperProcess(*testing.T) {
 
 		os.Exit(exitStatus)
 	case "panic-long":
-		exitStatus, err := BasicWrap(panicHandler)
+		done, exitStatus, err := BasicWrap(panicHandler)
 
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "wrap error: %s", err)
 			os.Exit(1)
 		}
 
-		if exitStatus < 0 {
+		if !done {
 			// Make a fake panic by faking the header and adding a
 			// bunch of garbage.
 			fmt.Fprint(os.Stderr, "panic: foo\n\n")
@@ -133,14 +133,14 @@ func TestHelperProcess(*testing.T) {
 			HidePanic: hidePanic,
 		}
 
-		exitStatus, err := Wrap(config)
+		done, exitStatus, err := Wrap(config)
 
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "wrap error: %s", err)
 			os.Exit(1)
 		}
 
-		if exitStatus < 0 {
+		if !done {
 			panic("uh oh")
 		}
 
@@ -154,13 +154,13 @@ func TestHelperProcess(*testing.T) {
 			Handler: panicHandler,
 		}
 
-		exitStatus, err := Wrap(config)
+		done, exitStatus, err := Wrap(config)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "wrap error: %s", err)
 			os.Exit(1)
 		}
 
-		if exitStatus < 0 {
+		if !done {
 			if child {
 				fmt.Printf("%v", Wrapped(nil))
 			}
@@ -181,7 +181,7 @@ func TestHelperProcess(*testing.T) {
 			os.Exit(0)
 		}
 
-		exitCode, err := Wrap(config)
+		_, exitCode, err := Wrap(config)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "wrap error: %s", err)
 			os.Exit(1)