cmd/utils, pkg/utils: Beautify the error messages for the distro option

containers#937

src/cmd/utils.go

@@ -71,6 +71,16 @@ func createErrorContainerNotFound(container string) error {
 	return errors.New(errMsg)
 }
 
+func createErrorDistroWithoutRelease(distro string) error {
+	var builder strings.Builder
+	fmt.Fprintf(&builder, "option '--release' is needed\n")
+	fmt.Fprintf(&builder, "Distribution %s doesn't match the host.\n", distro)
+	fmt.Fprintf(&builder, "Run '%s --help' for usage.", executableBase)
+
+	errMsg := builder.String()
+	return errors.New(errMsg)
+}
+
 func createErrorInvalidContainer(containerArg string) error {
 	var builder strings.Builder
 	fmt.Fprintf(&builder, "invalid argument for '%s'\n", containerArg)
@@ -81,6 +91,16 @@ func createErrorInvalidContainer(containerArg string) error {
 	return errors.New(errMsg)
 }
 
+func createErrorInvalidDistro(distro string) error {
+	var builder strings.Builder
+	fmt.Fprintf(&builder, "invalid argument for '--distro'\n")
+	fmt.Fprintf(&builder, "Distribution %s is unsupported.\n", distro)
+	fmt.Fprintf(&builder, "Run '%s --help' for usage.", executableBase)
+
+	errMsg := builder.String()
+	return errors.New(errMsg)
+}
+
 func createErrorInvalidImageForContainerName(container string) error {
 	var builder strings.Builder
 	fmt.Fprintf(&builder, "invalid argument for '--image'\n")
@@ -122,6 +142,7 @@ func resolveContainerAndImageNames(container, containerArg, distroCLI, imageCLI,
 
 	if err != nil {
 		var errContainer *utils.ContainerError
+		var errDistro *utils.DistroError
 		var errParseRelease *utils.ParseReleaseError
 
 		if errors.As(err, &errContainer) {
@@ -140,6 +161,17 @@ func resolveContainerAndImageNames(container, containerArg, distroCLI, imageCLI,
 				panicMsg := fmt.Sprintf("unexpected %T: %s", err, err)
 				panic(panicMsg)
 			}
+		} else if errors.As(err, &errDistro) {
+			if errors.Is(err, utils.ErrDistroUnsupported) {
+				err := createErrorInvalidDistro(errDistro.Distro)
+				return "", "", "", err
+			} else if errors.Is(err, utils.ErrDistroWithoutRelease) {
+				err := createErrorDistroWithoutRelease(errDistro.Distro)
+				return "", "", "", err
+			} else {
+				panicMsg := fmt.Sprintf("unexpected %T: %s", err, err)
+				panic(panicMsg)
+			}
 		} else if errors.As(err, &errParseRelease) {
 			err := createErrorInvalidRelease(errParseRelease.Hint)
 			return "", "", "", err

src/pkg/utils/errors.go

@@ -26,6 +26,11 @@ type ContainerError struct {
 	Err       error
 }
 
+type DistroError struct {
+	Distro string
+	Err    error
+}
+
 type ParseReleaseError struct {
 	Hint string
 }
@@ -39,6 +44,15 @@ func (err *ContainerError) Unwrap() error {
 	return err.Err
 }
 
+func (err *DistroError) Error() string {
+	errMsg := fmt.Sprintf("%s: %s", err.Distro, err.Err)
+	return errMsg
+}
+
+func (err *DistroError) Unwrap() error {
+	return err.Err
+}
+
 func (err *ParseReleaseError) Error() string {
 	return err.Hint
 }

src/pkg/utils/utils.go

@@ -121,6 +121,10 @@ var (
 	ErrContainerNameFromImageInvalid = errors.New("container name generated from image is invalid")
 
 	ErrContainerNameInvalid = errors.New("container name is invalid")
+
+	ErrDistroUnsupported = errors.New("distribution is unsupported")
+
+	ErrDistroWithoutRelease = errors.New("non-default distribution must specify release")
 )
 
 func init() {
@@ -713,11 +717,11 @@ func ResolveContainerAndImageNames(container, distroCLI, imageCLI, releaseCLI st
 	}
 
 	if _, ok := supportedDistros[distro]; !ok {
-		return "", "", "", fmt.Errorf("distribution %s is unsupported", distro)
+		return "", "", "", &DistroError{distro, ErrDistroUnsupported}
 	}
 
 	if distro != distroDefault && releaseCLI == "" && !viper.IsSet("general.release") {
-		return "", "", "", fmt.Errorf("release not found for non-default distribution %s", distro)
+		return "", "", "", &DistroError{distro, ErrDistroWithoutRelease}
 	}
 
 	if releaseCLI == "" {

test/system/101-create.bats

@@ -90,8 +90,10 @@ teardown() {
   run $TOOLBOX --assumeyes create --distro "$distro"
 
   assert_failure
-  assert_line --index 0 "Error: distribution $distro is unsupported"
-  assert [ ${#lines[@]} -eq 1 ]
+  assert_line --index 0 "Error: invalid argument for '--distro'"
+  assert_line --index 1 "Distribution $distro is unsupported."
+  assert_line --index 2 "Run 'toolbox --help' for usage."
+  assert [ ${#lines[@]} -eq 3 ]
 }
 
 @test "create: Try to create a container based on non-existent image" {
@@ -158,8 +160,10 @@ teardown() {
   run $TOOLBOX -y create -d "$distro"
 
   assert_failure
-  assert_line --index 0 "Error: release not found for non-default distribution $distro"
-  assert [ ${#lines[@]} -eq 1 ]
+  assert_line --index 0 "Error: option '--release' is needed"
+  assert_line --index 1 "Distribution $distro doesn't match the host."
+  assert_line --index 2 "Run 'toolbox --help' for usage."
+  assert [ ${#lines[@]} -eq 3 ]
 }
 
 @test "create: Try to create a container and pass a non-existent file to the --authfile option" {

test/system/104-run.bats

@@ -54,8 +54,10 @@ teardown() {
   run $TOOLBOX --assumeyes run --distro "$distro" ls
 
   assert_failure
-  assert_line --index 0 "Error: distribution $distro is unsupported"
-  assert [ ${#lines[@]} -eq 1 ]
+  assert_line --index 0 "Error: invalid argument for '--distro'"
+  assert_line --index 1 "Distribution $distro is unsupported."
+  assert_line --index 2 "Run 'toolbox --help' for usage."
+  assert [ ${#lines[@]} -eq 3 ]
 }
 
 @test "run: Try to run a command in a container based on Fedora but with wrong version" {
@@ -113,8 +115,10 @@ teardown() {
   run $TOOLBOX run -d "$distro" ls
 
   assert_failure
-  assert_line --index 0 "Error: release not found for non-default distribution $distro"
-  assert [ ${#lines[@]} -eq 1 ]
+  assert_line --index 0 "Error: option '--release' is needed"
+  assert_line --index 1 "Distribution $distro doesn't match the host."
+  assert_line --index 2 "Run 'toolbox --help' for usage."
+  assert [ ${#lines[@]} -eq 3 ]
 }
 
 @test "run: Run echo 'Hello World' inside of the default container" {

test/system/105-enter.bats

@@ -60,8 +60,10 @@ teardown() {
   run $TOOLBOX --assumeyes enter --distro "$distro"
 
   assert_failure
-  assert_line --index 0 "Error: distribution $distro is unsupported"
-  assert [ ${#lines[@]} -eq 1 ]
+  assert_line --index 0 "Error: invalid argument for '--distro'"
+  assert_line --index 1 "Distribution $distro is unsupported."
+  assert_line --index 2 "Run 'toolbox --help' for usage."
+  assert [ ${#lines[@]} -eq 3 ]
 }
 
 @test "enter: Try to enter a container based on Fedora but with wrong version" {
@@ -119,8 +121,10 @@ teardown() {
   run $TOOLBOX enter -d "$distro"
 
   assert_failure
-  assert_line --index 0 "Error: release not found for non-default distribution $distro"
-  assert [ ${#lines[@]} -eq 1 ]
+  assert_line --index 0 "Error: option '--release' is needed"
+  assert_line --index 1 "Distribution $distro doesn't match the host."
+  assert_line --index 2 "Run 'toolbox --help' for usage."
+  assert [ ${#lines[@]} -eq 3 ]
 }
 
 # TODO: Write the test