Revert "net/url: escape URL.RawQuery on Parse if it contains invalid characters"

This reverts commit CL 99135 (git rev 1040626c).

Reason for revert: breaks valid code; see #27302

Fixes #27302
Updates #22907

Change-Id: I82bb0c28ae1683140c71e7a2224c4ded3f4acea1
Reviewed-on: https://go-review.googlesource.com/137716Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/net/url/url.go

@@ -534,13 +534,7 @@ func parse(rawurl string, viaRequest bool) (*URL, error) {
 		url.ForceQuery = true
 		rest = rest[:len(rest)-1]
 	} else {
-		var q string
-		rest, q = split(rest, "?", true)
-		if validQuery(q) {
-			url.RawQuery = q
-		} else {
-			url.RawQuery = QueryEscape(q)
-		}
+		rest, url.RawQuery = split(rest, "?", true)
 	}
 
 	if !strings.HasPrefix(rest, "/") {
@@ -1139,46 +1133,3 @@ func validUserinfo(s string) bool {
 	}
 	return true
 }
-
-// validQuery reports whether s is a valid query string per RFC 3986
-// Section 3.4:
-//     query       = *( pchar / "/" / "?" )
-//     pchar       = unreserved / pct-encoded / sub-delims / ":" / "@"
-//     unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"
-//     sub-delims  = "!" / "$" / "&" / "'" / "(" / ")"
-//                   / "*" / "+" / "," / ";" / "="
-func validQuery(s string) bool {
-	pctEnc := 0
-
-	for _, r := range s {
-		if pctEnc > 0 {
-			if uint32(r) > 255 || !ishex(byte(r)) {
-				return false
-			}
-			pctEnc--
-			continue
-		} else if r == '%' {
-			pctEnc = 2
-			continue
-		}
-
-		if 'A' <= r && r <= 'Z' {
-			continue
-		}
-		if 'a' <= r && r <= 'z' {
-			continue
-		}
-		if '0' <= r && r <= '9' {
-			continue
-		}
-		switch r {
-		case '-', '.', '_', '~', '!', '$', '&', '\'', '(', ')',
-			'*', '+', ',', ';', '=', ':', '@', '/', '?':
-			continue
-		default:
-			return false
-		}
-	}
-
-	return true
-}

src/net/url/url_test.go

@@ -590,16 +590,6 @@ var urltests = []URLTest{
 		},
 		"mailto:?subject=hi",
 	},
-	{
-		"https://example.com/search?q=Фотки собак&source=lnms",
-		&URL{
-			Scheme:   "https",
-			Host:     "example.com",
-			Path:     "/search",
-			RawQuery: "q%3D%D0%A4%D0%BE%D1%82%D0%BA%D0%B8+%D1%81%D0%BE%D0%B1%D0%B0%D0%BA%26source%3Dlnms",
-		},
-		"https://example.com/search?q%3D%D0%A4%D0%BE%D1%82%D0%BA%D0%B8+%D1%81%D0%BE%D0%B1%D0%B0%D0%BA%26source%3Dlnms",
-	},
 }
 
 // more useful string for debugging than fmt's struct printer
@@ -1449,7 +1439,6 @@ func TestParseErrors(t *testing.T) {
 		{"cache_object:foo", true},
 		{"cache_object:foo/bar", true},
 		{"cache_object/:foo/bar", false},
-		{"https://example.com/search?q=Фотки собак&source=lnms", false},
 	}
 	for _, tt := range tests {
 		u, err := Parse(tt.in)