1 files changed, 92 insertions, 0 deletions
diff --git a/vendor/utf-8/src/lossy.rs b/vendor/utf-8/src/lossy.rs
new file mode 100644
index 000000000..00bcdecf0
--- /dev/null
+++ b/vendor/utf-8/src/lossy.rs
@@ -0,0 +1,92 @@
+use super::*;
+
+/// A push-based, lossy decoder for UTF-8.
+/// Errors are replaced with the U+FFFD replacement character.
+///
+/// Users “push” bytes into the decoder, which in turn “pushes” `&str` slices into a callback.
+///
+/// For example, `String::from_utf8_lossy` (but returning `String` instead of `Cow`)
+/// can be rewritten as:
+///
+/// ```rust
+/// fn string_from_utf8_lossy(input: &[u8]) -> String {
+///     let mut string = String::new();
+///     utf8::LossyDecoder::new(|s| string.push_str(s)).feed(input);
+///     string
+/// }
+/// ```
+///
+/// **Note:** Dropping the decoder signals the end of the input:
+/// If the last input chunk ended with an incomplete byte sequence for a code point,
+/// this is an error and a replacement character is emitted.
+/// Use `std::mem::forget` to inhibit this behavior.
+pub struct LossyDecoder<F: FnMut(&str)> {
+    push_str: F,
+    incomplete: Incomplete,
+}
+
+impl<F: FnMut(&str)> LossyDecoder<F> {
+    /// Create a new decoder from a callback.
+    #[inline]
+    pub fn new(push_str: F) -> Self {
+        LossyDecoder {
+            push_str: push_str,
+            incomplete: Incomplete {
+                buffer: [0, 0, 0, 0],
+                buffer_len: 0,
+            },
+        }
+    }
+
+    /// Feed one chunk of input into the decoder.
+    ///
+    /// The input is decoded lossily
+    /// and the callback called once or more with `&str` string slices.
+    ///
+    /// If the UTF-8 byte sequence for one code point was split into this bytes chunk
+    /// and previous bytes chunks, it will be correctly pieced back together.
+    pub fn feed(&mut self, mut input: &[u8]) {
+        if self.incomplete.buffer_len > 0 {
+            match self.incomplete.try_complete(input) {
+                Some((Ok(s), remaining)) => {
+                    (self.push_str)(s);
+                    input = remaining
+                }
+                Some((Err(_), remaining)) => {
+                    (self.push_str)(REPLACEMENT_CHARACTER);
+                    input = remaining
+                }
+                None => {
+                    return
+                }
+            }
+        }
+        loop {
+            match decode(input) {
+                Ok(s) => {
+                    (self.push_str)(s);
+                    return
+                }
+                Err(DecodeError::Incomplete { valid_prefix, incomplete_suffix }) => {
+                    (self.push_str)(valid_prefix);
+                    self.incomplete = incomplete_suffix;
+                    return
+                }
+                Err(DecodeError::Invalid { valid_prefix, remaining_input, .. }) => {
+                    (self.push_str)(valid_prefix);
+                    (self.push_str)(REPLACEMENT_CHARACTER);
+                    input = remaining_input
+                }
+            }
+        }
+    }
+}
+
+impl<F: FnMut(&str)> Drop for LossyDecoder<F> {
+    #[inline]
+    fn drop(&mut self) {
+        if self.incomplete.buffer_len > 0 {
+            (self.push_str)(REPLACEMENT_CHARACTER)
+        }
+    }
+}