Update overrideMimeType and final-charset to match xhr spec (#29812)

* Update overrideMimeType to match xhr spec

* Update final-encoding to match xhr spec

* Fix an issue and add more comments

---------

Co-authored-by: Martin Robinson <mrobinson@igalia.com>

components/script/dom/xmlhttprequest.rs

@@ -145,8 +145,6 @@ pub struct XMLHttpRequest {
     #[ignore_malloc_size_of = "Defined in hyper"]
     #[no_trace]
     override_mime_type: DomRefCell<Option<Mime>>,
-    #[no_trace]
-    override_charset: DomRefCell<Option<&'static Encoding>>,
 
     // Associated concepts
     #[ignore_malloc_size_of = "Defined in hyper"]
@@ -201,7 +199,6 @@ impl XMLHttpRequest {
             response_json: Heap::default(),
             response_headers: DomRefCell::new(HeaderMap::new()),
             override_mime_type: DomRefCell::new(None),
-            override_charset: DomRefCell::new(None),
 
             request_method: DomRefCell::new(Method::GET),
             request_url: DomRefCell::new(None),
@@ -892,31 +889,28 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
         ByteString::new(v)
     }
 
-    // https://xhr.spec.whatwg.org/#the-overridemimetype()-method
+    /// <https://xhr.spec.whatwg.org/#the-overridemimetype()-method>
     fn OverrideMimeType(&self, mime: DOMString) -> ErrorResult {
-        // Step 1
+        // 1. If this’s state is loading or done, then throw an "InvalidStateError"
+        //   DOMException.
         match self.ready_state.get() {
             XMLHttpRequestState::Loading | XMLHttpRequestState::Done => {
                 return Err(Error::InvalidState);
             },
             _ => {},
         }
-        // Step 2
+
-        let override_mime = mime.parse::<Mime>().map_err(|_| Error::Syntax)?;
+        // 2. Set this’s override MIME type to the result of parsing mime.
-        // Step 3
+        // 3. If this’s override MIME type is failure, then set this’s override MIME type
-        let mime_str = override_mime.as_ref();
+        //    to application/octet-stream.
-        let mime_parts: Vec<&str> = mime_str.split(";").collect();
+        let override_mime = match mime.parse::<Mime>() {
-        let mime_no_params = if mime_parts.len() > 1 {
+            Ok(mime) => mime,
-            mime_parts[0].parse().unwrap()
+            Err(_) => "application/octet-stream"
-        } else {
+                .parse::<Mime>()
-            override_mime.clone()
+                .map_err(|_| Error::Syntax)?,
         };
 
-        *self.override_mime_type.borrow_mut() = Some(mime_no_params);
+        *self.override_mime_type.borrow_mut() = Some(override_mime);
-        // Step 4
-        let value = override_mime.get_param(mime::CHARSET);
-        *self.override_charset.borrow_mut() =
-            value.and_then(|value| Encoding::for_label(value.as_ref().as_bytes()));
         Ok(())
     }
 
@@ -1604,19 +1598,29 @@ impl XMLHttpRequest {
         Ok(())
     }
 
+    /// <https://xhr.spec.whatwg.org/#final-charset>
     fn final_charset(&self) -> Option<&'static Encoding> {
-        if self.override_charset.borrow().is_some() {
+        // 1. Let label be null.
-            self.override_charset.borrow().clone()
+        // 2. Let responseMIME be the result of get a response MIME type for xhr.
-        } else {
+        // 3. If responseMIME’s parameters["charset"] exists, then set label to it.
-            match self.response_headers.borrow().typed_get::<ContentType>() {
+        let response_charset = self
-                Some(ct) => {
+            .response_mime_type()
-                    let mime: Mime = ct.into();
+            .and_then(|mime| mime.get_param(mime::CHARSET).map(|c| c.to_string()));
-                    let value = mime.get_param(mime::CHARSET);
+
-                    value.and_then(|value| Encoding::for_label(value.as_ref().as_bytes()))
+        // 4. If xhr’s override MIME type’s parameters["charset"] exists, then set label to it.
-                },
+        let override_charset = self
-                None => None,
+            .override_mime_type
-            }
+            .borrow()
-        }
+            .as_ref()
+            .and_then(|mime| mime.get_param(mime::CHARSET).map(|c| c.to_string()));
+
+        // 5. If label is null, then return null.
+        // 6. Let encoding be the result of getting an encoding from label.
+        // 7. If encoding is failure, then return null.
+        // 8. Return encoding.
+        override_charset
+            .or(response_charset)
+            .and_then(|charset| Encoding::for_label(&charset.as_bytes()))
     }
 
     /// <https://xhr.spec.whatwg.org/#response-mime-type>

tests/wpt/meta-legacy-layout/encoding/single-byte-decoder.window.js.ini

@@ -1,31 +1,4 @@
 [single-byte-decoder.window.html?XMLHttpRequest]
-  [ISO-8859-2: iso_8859-2:1987 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-3: iso_8859-3:1988 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-4: iso_8859-4:1988 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-5: iso_8859-5:1988 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-6: iso_8859-6:1987 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-7: iso_8859-7:1987 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-8: iso_8859-8:1988 (XMLHttpRequest)]
-    expected: FAIL
-
-  [windows-1252: iso_8859-1:1987 (XMLHttpRequest)]
-    expected: FAIL
-
-  [windows-1254: iso_8859-9:1989 (XMLHttpRequest)]
-    expected: FAIL
-
 
 [single-byte-decoder.window.html?TextDecoder]
 

tests/wpt/meta-legacy-layout/xhr/overridemimetype-blob.html.ini

@@ -6,9 +6,6 @@
   [Bogus MIME type should end up as application/octet-stream, 2]
     expected: FAIL
 
-  [1) MIME types need to be parsed and serialized: text/html;charset=gbk]
-    expected: FAIL
-
   [2) MIME types need to be parsed and serialized: TEXT/HTML;CHARSET=GBK]
     expected: FAIL
 
@@ -204,9 +201,6 @@
   [39) MIME types need to be parsed and serialized: x/x;test]
     expected: FAIL
 
-  [16) MIME types need to be parsed and serialized: text/html;charset='gbk']
-    expected: FAIL
-
   [63) MIME types need to be parsed and serialized: </>]
     expected: FAIL
 
@@ -264,9 +258,6 @@
   [26) MIME types need to be parsed and serialized: text/html;charset= ";charset=GBK]
     expected: FAIL
 
-  [17) MIME types need to be parsed and serialized: text/html;charset='gbk]
-    expected: FAIL
-
   [25) MIME types need to be parsed and serialized: text/html;;;;charset=gbk]
     expected: FAIL
 
@@ -339,9 +330,6 @@
   [48) MIME types need to be parsed and serialized: \n\r\t x/x;x=x\n\r\t ]
     expected: FAIL
 
-  [31) MIME types need to be parsed and serialized: text/html;charset=" gbk"]
-    expected: FAIL
-
   [49) MIME types need to be parsed and serialized: x/x;\n\r\t x=x\n\r\t ;x=y]
     expected: FAIL
 
@@ -354,9 +342,6 @@
   [12) MIME types need to be parsed and serialized: text/html;charset=\x0bgbk]
     expected: FAIL
 
-  [32) MIME types need to be parsed and serialized: text/html;charset="gbk "]
-    expected: FAIL
-
   [53) MIME types need to be parsed and serialized: \x0cx/x]
     expected: FAIL
 
@@ -366,12 +351,6 @@
   [24) MIME types need to be parsed and serialized: text/html ; ; charset=gbk]
     expected: FAIL
 
-  [18) MIME types need to be parsed and serialized: text/html;charset=gbk']
-    expected: FAIL
-
-  [39) MIME types need to be parsed and serialized: text/html;0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789=x;charset=gbk]
-    expected: FAIL
-
   [65) MIME types need to be parsed and serialized: ÿ/ÿ]
     expected: FAIL
 
@@ -399,9 +378,6 @@
   [41) MIME types need to be parsed and serialized: text/html;a\]=bar;b[=bar;c=bar]
     expected: FAIL
 
-  [42) MIME types need to be parsed and serialized: text/html;valid=";";foo=bar]
-    expected: FAIL
-
   [43) MIME types need to be parsed and serialized: text/html;in\]valid=";asd=foo";foo=bar]
     expected: FAIL
 
@@ -438,62 +414,5 @@
   [54) MIME types need to be parsed and serialized: x/x;test=<3D>;x=x]
     expected: FAIL
 
-  [55) MIME types need to be parsed and serialized: \x0bx/x]
-    expected: FAIL
-
-  [56) MIME types need to be parsed and serialized: \x0cx/x]
-    expected: FAIL
-
-  [57) MIME types need to be parsed and serialized: x/x\x0b]
-    expected: FAIL
-
-  [58) MIME types need to be parsed and serialized: x/x\x0c]
-    expected: FAIL
-
-  [59) MIME types need to be parsed and serialized: ]
-    expected: FAIL
-
-  [60) MIME types need to be parsed and serialized: \t]
-    expected: FAIL
-
-  [61) MIME types need to be parsed and serialized: /]
-    expected: FAIL
-
-  [62) MIME types need to be parsed and serialized: bogus]
-    expected: FAIL
-
   [63) MIME types need to be parsed and serialized: bogus/]
     expected: FAIL
-
-  [64) MIME types need to be parsed and serialized: bogus/ ]
-    expected: FAIL
-
-  [65) MIME types need to be parsed and serialized: bogus/bogus/;]
-    expected: FAIL
-
-  [66) MIME types need to be parsed and serialized: </>]
-    expected: FAIL
-
-  [67) MIME types need to be parsed and serialized: (/)]
-    expected: FAIL
-
-  [68) MIME types need to be parsed and serialized: ÿ/ÿ]
-    expected: FAIL
-
-  [69) MIME types need to be parsed and serialized: text/html(;doesnot=matter]
-    expected: FAIL
-
-  [70) MIME types need to be parsed and serialized: {/}]
-    expected: FAIL
-
-  [71) MIME types need to be parsed and serialized: Ā/Ā]
-    expected: FAIL
-
-  [72) MIME types need to be parsed and serialized: text /html]
-    expected: FAIL
-
-  [73) MIME types need to be parsed and serialized: text/ html]
-    expected: FAIL
-
-  [74) MIME types need to be parsed and serialized: "text/html"]
-    expected: FAIL

tests/wpt/meta-legacy-layout/xhr/overridemimetype-edge-cases.window.js.ini

@@ -1,7 +1,3 @@
 [overridemimetype-edge-cases.window.html]
   [overrideMimeType() state needs to be reset across requests]
     expected: FAIL
-
-  [Charset can be overridden by overrideMimeType() with a bogus charset]
-    expected: FAIL
-

tests/wpt/meta-legacy-layout/xhr/overridemimetype-invalid-mime-type.htm.ini

@@ -1,11 +0,0 @@
-[overridemimetype-invalid-mime-type.htm]
-  type: testharness
-  [Bogus MIME type does not override encoding]
-    expected: FAIL
-
-  [Bogus MIME type does not override encoding, 2]
-    expected: FAIL
-
-  [Bogus MIME type does override MIME type]
-    expected: FAIL
-

tests/wpt/meta/encoding/single-byte-decoder.window.js.ini

@@ -1,31 +1,4 @@
 [single-byte-decoder.window.html?XMLHttpRequest]
-  [ISO-8859-2: iso_8859-2:1987 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-3: iso_8859-3:1988 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-4: iso_8859-4:1988 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-5: iso_8859-5:1988 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-6: iso_8859-6:1987 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-7: iso_8859-7:1987 (XMLHttpRequest)]
-    expected: FAIL
-
-  [ISO-8859-8: iso_8859-8:1988 (XMLHttpRequest)]
-    expected: FAIL
-
-  [windows-1252: iso_8859-1:1987 (XMLHttpRequest)]
-    expected: FAIL
-
-  [windows-1254: iso_8859-9:1989 (XMLHttpRequest)]
-    expected: FAIL
-
 
 [single-byte-decoder.window.html?TextDecoder]
 

tests/wpt/meta/xhr/overridemimetype-blob.html.ini

@@ -1,7 +1,4 @@
 [overridemimetype-blob.html]
-  [1) MIME types need to be parsed and serialized: text/html;charset=gbk]
-    expected: FAIL
-
   [2) MIME types need to be parsed and serialized: TEXT/HTML;CHARSET=GBK]
     expected: FAIL
 
@@ -44,15 +41,6 @@
   [15) MIME types need to be parsed and serialized: text/html;\x0ccharset=gbk]
     expected: FAIL
 
-  [16) MIME types need to be parsed and serialized: text/html;charset='gbk']
-    expected: FAIL
-
-  [17) MIME types need to be parsed and serialized: text/html;charset='gbk]
-    expected: FAIL
-
-  [18) MIME types need to be parsed and serialized: text/html;charset=gbk']
-    expected: FAIL
-
   [19) MIME types need to be parsed and serialized: text/html;charset=';charset=GBK]
     expected: FAIL
 
@@ -89,12 +77,6 @@
   [30) MIME types need to be parsed and serialized: text/html;charset=gbk"]
     expected: FAIL
 
-  [31) MIME types need to be parsed and serialized: text/html;charset=" gbk"]
-    expected: FAIL
-
-  [32) MIME types need to be parsed and serialized: text/html;charset="gbk "]
-    expected: FAIL
-
   [33) MIME types need to be parsed and serialized: text/html;charset="\\ gbk"]
     expected: FAIL
 
@@ -113,15 +95,9 @@
   [38) MIME types need to be parsed and serialized: text/html;charset={gbk}]
     expected: FAIL
 
-  [39) MIME types need to be parsed and serialized: text/html;0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789=x;charset=gbk]
-    expected: FAIL
-
   [41) MIME types need to be parsed and serialized: text/html;a\]=bar;b[=bar;c=bar]
     expected: FAIL
 
-  [42) MIME types need to be parsed and serialized: text/html;valid=";";foo=bar]
-    expected: FAIL
-
   [43) MIME types need to be parsed and serialized: text/html;in\]valid=";asd=foo";foo=bar]
     expected: FAIL
 
@@ -158,62 +134,5 @@
   [54) MIME types need to be parsed and serialized: x/x;test=<3D>;x=x]
     expected: FAIL
 
-  [55) MIME types need to be parsed and serialized: \x0bx/x]
-    expected: FAIL
-
-  [56) MIME types need to be parsed and serialized: \x0cx/x]
-    expected: FAIL
-
-  [57) MIME types need to be parsed and serialized: x/x\x0b]
-    expected: FAIL
-
-  [58) MIME types need to be parsed and serialized: x/x\x0c]
-    expected: FAIL
-
-  [59) MIME types need to be parsed and serialized: ]
-    expected: FAIL
-
-  [60) MIME types need to be parsed and serialized: \t]
-    expected: FAIL
-
-  [61) MIME types need to be parsed and serialized: /]
-    expected: FAIL
-
-  [62) MIME types need to be parsed and serialized: bogus]
-    expected: FAIL
-
   [63) MIME types need to be parsed and serialized: bogus/]
     expected: FAIL
-
-  [64) MIME types need to be parsed and serialized: bogus/ ]
-    expected: FAIL
-
-  [65) MIME types need to be parsed and serialized: bogus/bogus/;]
-    expected: FAIL
-
-  [66) MIME types need to be parsed and serialized: </>]
-    expected: FAIL
-
-  [67) MIME types need to be parsed and serialized: (/)]
-    expected: FAIL
-
-  [68) MIME types need to be parsed and serialized: ÿ/ÿ]
-    expected: FAIL
-
-  [69) MIME types need to be parsed and serialized: text/html(;doesnot=matter]
-    expected: FAIL
-
-  [70) MIME types need to be parsed and serialized: {/}]
-    expected: FAIL
-
-  [71) MIME types need to be parsed and serialized: Ā/Ā]
-    expected: FAIL
-
-  [72) MIME types need to be parsed and serialized: text /html]
-    expected: FAIL
-
-  [73) MIME types need to be parsed and serialized: text/ html]
-    expected: FAIL
-
-  [74) MIME types need to be parsed and serialized: "text/html"]
-    expected: FAIL

tests/wpt/meta/xhr/overridemimetype-edge-cases.window.js.ini

@@ -1,3 +0,0 @@
-[overridemimetype-edge-cases.window.html]
-  [Charset can be overridden by overrideMimeType() with a bogus charset]
-    expected: FAIL

tests/wpt/meta/xhr/overridemimetype-invalid-mime-type.htm.ini

@@ -1,9 +0,0 @@
-[overridemimetype-invalid-mime-type.htm]
-  [Bogus MIME type does not override encoding]
-    expected: FAIL
-
-  [Bogus MIME type does not override encoding, 2]
-    expected: FAIL
-
-  [Bogus MIME type does override MIME type]
-    expected: FAIL