Rewrite Blob constructor interface

components/script/dom/blob.rs

@@ -28,6 +28,7 @@ pub struct DataSlice {
 }
 
 impl DataSlice {
+    /// Construct DataSlice from reference counted bytes
     pub fn new(bytes: Arc<Vec<u8>>, start: Option<i64>, end: Option<i64>) -> DataSlice {
         let size = bytes.len() as i64;
         let relativeStart: i64 = match start {
@@ -62,14 +63,21 @@ impl DataSlice {
         }
     }
 
+    /// Construct an empty data slice
+    pub fn empty() -> DataSlice {
+        DataSlice {
+            bytes: Arc::new(Vec::new()),
+            bytes_start: 0,
+            bytes_end: 0,
+        }
+    }
+
+    /// Get sliced bytes
     pub fn get_bytes(&self) -> &[u8] {
         &self.bytes[self.bytes_start..self.bytes_end]
     }
 
-    pub fn get_all_bytes(&self) -> Arc<Vec<u8>> {
-        self.bytes.clone()
-    }
-
+    /// Get length of sliced bytes
     pub fn size(&self) -> u64 {
         (self.bytes_end as u64) - (self.bytes_start as u64)
     }
@@ -86,38 +94,20 @@ pub struct Blob {
     isClosed_: Cell<bool>,
 }
 
-fn is_ascii_printable(string: &str) -> bool {
-    // Step 5.1 in Sec 5.1 of File API spec
-    // https://w3c.github.io/FileAPI/#constructorBlob
-    string.chars().all(|c| c >= '\x20' && c <= '\x7E')
-}
-
 impl Blob {
-    pub fn new_inherited(bytes: Arc<Vec<u8>>,
-                         bytes_start: Option<i64>,
-                         bytes_end: Option<i64>,
-                         typeString: &str) -> Blob {
-        Blob {
-            reflector_: Reflector::new(),
-            data: DataSlice::new(bytes, bytes_start, bytes_end),
-            typeString: typeString.to_owned(),
-            isClosed_: Cell::new(false),
-        }
-    }
 
-    pub fn new(global: GlobalRef, bytes: Vec<u8>, typeString: &str) -> Root<Blob> {
-        let boxed_blob = box Blob::new_inherited(Arc::new(bytes), None, None, typeString);
+    pub fn new(global: GlobalRef, slice: DataSlice, typeString: &str) -> Root<Blob> {
+        let boxed_blob = box Blob::new_inherited(slice, typeString);
         reflect_dom_object(boxed_blob, global, BlobBinding::Wrap)
     }
 
-    fn new_sliced(global: GlobalRef,
-                  bytes: Arc<Vec<u8>>,
-                  bytes_start: Option<i64>,
-                  bytes_end: Option<i64>,
-                  typeString: &str) -> Root<Blob> {
-
-      let boxed_blob = box Blob::new_inherited(bytes, bytes_start, bytes_end, typeString);
-      reflect_dom_object(boxed_blob, global, BlobBinding::Wrap)
+    pub fn new_inherited(slice: DataSlice, typeString: &str) -> Blob {
+        Blob {
+            reflector_: Reflector::new(),
+            data: slice,
+            typeString: typeString.to_owned(),
+            isClosed_: Cell::new(false),
+        }
     }
 
     // https://w3c.github.io/FileAPI/#constructorBlob
@@ -143,12 +133,9 @@ impl Blob {
                 .collect()
             }
         };
-        let typeString = if is_ascii_printable(&blobPropertyBag.type_) {
-            &*blobPropertyBag.type_
-        } else {
-            ""
-        };
-        Ok(Blob::new(global, bytes, &typeString.to_ascii_lowercase()))
+
+        let slice = DataSlice::new(Arc::new(bytes), None, None);
+        Ok(Blob::new(global, slice, blobPropertyBag.get_typestring()))
     }
 
     pub fn get_data(&self) -> &DataSlice {
@@ -187,7 +174,7 @@ impl BlobMethods for Blob {
         };
         let global = self.global();
         let bytes = self.data.bytes.clone();
-        Blob::new_sliced(global.r(), bytes, start, end, &relativeContentType)
+        Blob::new(global.r(), DataSlice::new(bytes, start, end), &relativeContentType)
     }
 
     // https://w3c.github.io/FileAPI/#dfn-isClosed
@@ -209,3 +196,20 @@ impl BlobMethods for Blob {
 
     }
 }
+
+
+impl BlobBinding::BlobPropertyBag {
+    pub fn get_typestring(&self) -> &str {
+        if is_ascii_printable(&self.type_) {
+            &*self.type_
+        } else {
+            ""
+        }
+    }
+}
+
+fn is_ascii_printable(string: &str) -> bool {
+    // Step 5.1 in Sec 5.1 of File API spec
+    // https://w3c.github.io/FileAPI/#constructorBlob
+    string.chars().all(|c| c >= '\x20' && c <= '\x7E')
+}