Tweak errors

urns/parser.go

@@ -7,13 +7,6 @@ import (
 
 // Simple URN parser loosely based on RFC2141 (https://www.ietf.org/rfc/rfc2141.txt)
 
-const (
-	stateScheme = iota
-	statePath
-	stateQuery
-	stateFragment
-)
-
 var escapes = map[rune]string{
 	'#': `%23`,
 	'%': `%25`,
@@ -39,6 +32,13 @@ func (u *parsedURN) String() string {
 	return s
 }
 
+const (
+	stateScheme = iota
+	statePath
+	stateQuery
+	stateFragment
+)
+
 func parseURN(urn string) (*parsedURN, error) {
 	state := stateScheme
 
@@ -74,8 +74,11 @@ func parseURN(urn string) (*parsedURN, error) {
 		buffers[state].WriteRune(c)
 	}
 
-	if state == stateScheme || buffers[stateScheme].Len() == 0 {
-		return nil, fmt.Errorf("must contain at least scheme and path")
+	if buffers[stateScheme].Len() == 0 {
+		return nil, fmt.Errorf("scheme cannot be empty")
+	}
+	if buffers[statePath].Len() == 0 {
+		return nil, fmt.Errorf("path cannot be empty")
 	}
 
 	return &parsedURN{

urns/parser_test.go

@@ -29,8 +29,9 @@ func TestParseURNAndBack(t *testing.T) {
 		// can't single part
 		{input: "xyz", hasError: true},
 
-		// can't omit scheme
+		// can't omit scheme or path
 		{input: ":path", hasError: true},
+		{input: "scheme:", hasError: true},
 
 		// can't have multiple queries or fragments
 		{input: "scheme:path?query?query", hasError: true},

urns/urns.go

@@ -175,14 +175,14 @@ func (u URN) Normalize(country string) URN {
 // Validate returns whether this URN is considered valid
 func (u URN) Validate() error {
 	scheme, path, _, display := u.ToParts()
+
+	if scheme == "" || path == "" {
+		return fmt.Errorf("scheme or path cannot be empty")
+	}
 	if !IsValidScheme(scheme) {
 		return fmt.Errorf("invalid scheme: '%s'", scheme)
 	}
 
-	if path == "" {
-		return fmt.Errorf("path cannot be empty")
-	}
-
 	switch scheme {
 	case TelScheme:
 		// validate is possible phone number

urns/urns_test.go

@@ -233,9 +233,9 @@ func TestValidate(t *testing.T) {
 		urn           URN
 		expectedError string
 	}{
-		{"xxxx", "invalid scheme"},    // un-parseable URNs don't validate
-		{"xyz:abc", "invalid scheme"}, // nor do unknown schemes
-		{"tel:", "path cannot be empty"},
+		{"xxxx", "scheme or path cannot be empty"}, // un-parseable URNs don't validate
+		{"xyz:abc", "invalid scheme"},              // nor do unknown schemes
+		{"tel:", "scheme or path cannot be empty"},
 
 		// valid tel numbers
 		{"tel:+250788383383", ""},
@@ -301,7 +301,7 @@ func TestValidate(t *testing.T) {
 			}
 
 			if err != nil && !strings.Contains(err.Error(), tc.expectedError) {
-				t.Errorf("Failed wrong error, '%s' not found in '%s'", tc.expectedError, err.Error())
+				t.Errorf("Failed wrong error, '%s' not found in '%s' for '%s'", tc.expectedError, err.Error(), string(tc.urn))
 			}
 		}