Added fix and tests

Author: cgopalan

src/net/url/url.go

@@ -433,11 +433,20 @@ func (u *Userinfo) String() string {
 // (Scheme must be [a-zA-Z][a-zA-Z0-9+-.]*)
 // If so, return scheme, path; else return "", rawurl.
 func getscheme(rawurl string) (scheme, path string, err error) {
+	// Validate the scheme
+	if ci := strings.IndexByte(rawurl, ':'); ci >= 0 {
+		var r byte
+		if ei := strings.IndexByte(rawurl, '='); ei >= 0 && ei < ci {
+			r = rawurl[ei+1]
+		} else {
+			r = rawurl[0]
+		}
+		if r < 'A' || (r > 'Z' && r < 'a') || r > 'z' {
+			return "", "", errors.New("url scheme has invalid character")
+		}
+	}
 	for i := 0; i < len(rawurl); i++ {
 		c := rawurl[i]
-		if i == 0 && c != '/' && c != '.' && c != '?' && c != ';' && (c < 'A' || (c > 'Z' && c < 'a') || c > 'z') {
-			return "", "", errors.New("URL scheme has invalid character")
-		}
 		switch {
 		case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z':
 		// do nothing

src/net/url/url_test.go

@@ -681,12 +681,6 @@ var parseRequestURLTests = []struct {
 	// RFC 6874.
 	{"http://[fe80::1%en0]/", false},
 	{"http://[fe80::1%en0]:8080/", false},
-
-	// Testing valid and invalid URL schemes
-	{"ahttp://example.com", true},
-	{" http://example.com", false},
-	{"+http://example.com", false},
-	{"1http://example.com", false},
 }
 
 func TestParseRequestURI(t *testing.T) {
@@ -1873,3 +1867,27 @@ func BenchmarkPathUnescape(b *testing.B) {
 		})
 	}
 }
+
+var urlSchemeValidTests = []struct {
+	url           string
+	expectedValid bool
+}{
+	{"ahttp://example.com", true},
+	{" http://example.com", false},
+	{"+http://example.com", false},
+	{"example.com", false},
+}
+
+func TestValidUrlSchemes(t *testing.T) {
+	for _, test := range urlSchemeValidTests {
+		_, err := ParseRequestURI(test.url)
+		if test.expectedValid && err != nil {
+			t.Errorf("ParseRequestURI(%q) gave err %v; want no error", test.url, err)
+		} else if !test.expectedValid && err == nil {
+			t.Errorf("ParseRequestURI(%q) gave nil error; want some error", test.url)
+		} else if !test.expectedValid && err != nil && !strings.ContainsAny(err.Error(), "Url scheme has invalid character!!") {
+			//t.Errorf("Error was %v", err.Error())
+			t.Errorf("ParseRequestURI(%q) gave error %v; want Invalid scheme error", test.url, err)
+		}
+	}
+}