Auto merge of #20413 - christianpoveda:issue_20344, r=jdm

TextDecoder's Decode now receives a BufferSource as input

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r? jdm

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #20344 (github issue number if applicable).

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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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components/script/dom/textdecoder.rs

@@ -3,7 +3,8 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use dom::bindings::codegen::Bindings::TextDecoderBinding;
-use dom::bindings::codegen::Bindings::TextDecoderBinding::TextDecoderMethods;
+use dom::bindings::codegen::Bindings::TextDecoderBinding::{TextDecoderMethods, TextDecodeOptions};
+use dom::bindings::codegen::UnionTypes::ArrayBufferViewOrArrayBuffer;
 use dom::bindings::error::{Error, Fallible};
 use dom::bindings::reflector::{Reflector, reflect_dom_object};
 use dom::bindings::root::DomRoot;
@@ -11,7 +12,6 @@ use dom::bindings::str::{DOMString, USVString};
 use dom::globalscope::GlobalScope;
 use dom_struct::dom_struct;
 use encoding_rs::Encoding;
-use js::jsapi::{JSContext, JSObject};
 use std::borrow::ToOwned;
 
 #[dom_struct]
@@ -65,32 +65,30 @@ impl TextDecoderMethods for TextDecoder {
         self.fatal
     }
 
-    #[allow(unsafe_code)]
     // https://encoding.spec.whatwg.org/#dom-textdecoder-decode
-    unsafe fn Decode(&self, _cx: *mut JSContext, input: Option<*mut JSObject>)
-              -> Fallible<USVString> {
-        let input = match input {
-            Some(input) => input,
-            None => return Ok(USVString("".to_owned())),
-        };
-
-        typedarray!(in(_cx) let data_res: ArrayBufferView = input);
-        let mut data = match data_res {
-            Ok(data) => data,
-            Err(_)   => {
-                return Err(Error::Type("Argument to TextDecoder.decode is not an ArrayBufferView".to_owned()));
+    fn Decode(
+        &self,
+        input: Option<ArrayBufferViewOrArrayBuffer>,
+        _options: &TextDecodeOptions
+    ) -> Fallible<USVString> {
+        match input {
+            Some(arr) => {
+                let vec: Vec<u8> = match arr {
+                    ArrayBufferViewOrArrayBuffer::ArrayBufferView(mut a) => a.to_vec(),
+                    ArrayBufferViewOrArrayBuffer::ArrayBuffer(mut a) => a.to_vec()
+                };
+                let s = if self.fatal {
+                    match self.encoding.decode_without_bom_handling_and_without_replacement(&vec) {
+                        Some(s) => s,
+                        None => return Err(Error::Type("Decoding failed".to_owned())),
+                    }
+                } else {
+                    let (s, _has_errors) = self.encoding.decode_without_bom_handling(&vec);
+                    s
+                };
+                Ok(USVString(s.into_owned()))
             }
-        };
-
-        let s = if self.fatal {
-            match self.encoding.decode_without_bom_handling_and_without_replacement(data.as_slice()) {
-                Some(s) => s,
-                None => return Err(Error::Type("Decoding failed".to_owned())),
-            }
-        } else {
-            let (s, _has_errors) = self.encoding.decode_without_bom_handling(data.as_slice());
-            s
-        };
-        Ok(USVString(s.into_owned()))
+            None => Ok(USVString("".to_owned()))
+        }
     }
 }

components/script/dom/webidls/TextDecoder.webidl

@@ -5,15 +5,18 @@
 // https://encoding.spec.whatwg.org/#interface-textdecoder
 dictionary TextDecoderOptions {
   boolean fatal = false;
-  //boolean ignoreBOM = false;
+  // boolean ignoreBOM = false;
+};
+
+dictionary TextDecodeOptions {
+  // boolean stream = false;
 };
 
 [Constructor(optional DOMString label = "utf-8", optional TextDecoderOptions options), Exposed=(Window,Worker)]
 interface TextDecoder {
   readonly attribute DOMString encoding;
   readonly attribute boolean fatal;
-  //readonly attribute boolean ignoreBOM;
-  //USVString decode(optional BufferSource input, optional TextDecodeOptions options);
+  // readonly attribute boolean ignoreBOM;
   [Throws]
-  USVString decode(optional object input);
+  USVString decode(optional BufferSource input, optional TextDecodeOptions options);
 };