Auto merge of #408 - valenting:path-percent-2e, r=SimonSapin

Don't percent decode %2e all the time in the path

Implements https://github.com/whatwg/url/pull/156

Imports tests from: https://github.com/w3c/web-platform-tests/commit/d93247d5cb7d70f80da8b154a171f4e3d50969f4

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src/parser.rs

@@ -920,15 +920,6 @@ impl<'a> Parser<'a> {
                     },
                     _ => {
                         self.check_url_code_point(c, &input);
-                        if c == '%' {
-                            let after_percent_sign = input.clone();
-                            if matches!(input.next(), Some('2')) &&
-                                    matches!(input.next(), Some('E') | Some('e')) {
-                                self.serialization.push('.');
-                                continue
-                            }
-                            input = after_percent_sign
-                        }
                         if self.context == Context::PathSegmentSetter {
                             self.serialization.extend(utf8_percent_encode(
                                 utf8_c, PATH_SEGMENT_ENCODE_SET));
@@ -940,7 +931,7 @@ impl<'a> Parser<'a> {
                 }
             }
             match &self.serialization[segment_start..] {
-                ".." => {
+                ".." | "%2e%2e" | "%2e%2E" | "%2E%2e" | "%2E%2E" | "%2e." | "%2E." | ".%2e" | ".%2E"  => {
                     debug_assert!(self.serialization.as_bytes()[segment_start - 1] == b'/');
                     self.serialization.truncate(segment_start - 1);  // Truncate "/.."
                     self.pop_path(scheme_type, path_start);
@@ -948,7 +939,7 @@ impl<'a> Parser<'a> {
                         self.serialization.push('/')
                     }
                 },
-                "." => {
+                "." | "%2e" | "%2E" => {
                     self.serialization.truncate(segment_start);
                 },
                 _ => {

tests/setters_tests.json

@@ -970,8 +970,8 @@
             "href": "view-source+http://example.net/home?lang=fr#nav",
             "new_value": "\\a\\%2E\\b\\%2e.\\c",
             "expected": {
-                "href": "view-source+http://example.net/\\a\\.\\b\\..\\c?lang=fr#nav",
-                "pathname": "/\\a\\.\\b\\..\\c"
+                "href": "view-source+http://example.net/\\a\\%2E\\b\\%2e.\\c?lang=fr#nav",
+                "pathname": "/\\a\\%2E\\b\\%2e.\\c"
             }
         },
         {
@@ -984,12 +984,12 @@
             }
         },
         {
-            "comment": "Bytes already percent-encoded are left as-is, except %2E.",
+            "comment": "Bytes already percent-encoded are left as-is, including %2E outside dotted segments.",
             "href": "http://example.net",
             "new_value": "%2e%2E%c3%89té",
             "expected": {
-                "href": "http://example.net/..%c3%89t%C3%A9",
-                "pathname": "/..%c3%89t%C3%A9"
+                "href": "http://example.net/%2e%2E%c3%89t%C3%A9",
+                "pathname": "/%2e%2E%c3%89t%C3%A9"
             }
         }
     ],

tests/urltestdata.json

@@ -1845,7 +1845,7 @@
   {
     "input": "http://example.com/foo/%2e%2",
     "base": "about:blank",
-    "href": "http://example.com/foo/.%2",
+    "href": "http://example.com/foo/%2e%2",
     "origin": "http://example.com",
     "protocol": "http:",
     "username": "",
@@ -1853,14 +1853,14 @@
     "host": "example.com",
     "hostname": "example.com",
     "port": "",
-    "pathname": "/foo/.%2",
+    "pathname": "/foo/%2e%2",
     "search": "",
     "hash": ""
   },
   {
     "input": "http://example.com/foo/%2e./%2e%2e/.%2e/%2e.bar",
     "base": "about:blank",
-    "href": "http://example.com/..bar",
+    "href": "http://example.com/%2e.bar",
     "origin": "http://example.com",
     "protocol": "http:",
     "username": "",
@@ -1868,7 +1868,7 @@
     "host": "example.com",
     "hostname": "example.com",
     "port": "",
-    "pathname": "/..bar",
+    "pathname": "/%2e.bar",
     "search": "",
     "hash": ""
   },
@@ -2286,7 +2286,7 @@
   {
     "input": "http://www/foo%2Ehtml",
     "base": "about:blank",
-    "href": "http://www/foo.html",
+    "href": "http://www/foo%2Ehtml",
     "origin": "http://www",
     "protocol": "http:",
     "username": "",
@@ -2294,7 +2294,7 @@
     "host": "www",
     "hostname": "www",
     "port": "",
-    "pathname": "/foo.html",
+    "pathname": "/foo%2Ehtml",
     "search": "",
     "hash": ""
   },