1 files changed, 132 insertions, 0 deletions
diff --git a/vendor/minifier/src/json/read/byte_to_char.rs b/vendor/minifier/src/json/read/byte_to_char.rs
new file mode 100644
index 000000000..d3618b9cb
--- /dev/null
+++ b/vendor/minifier/src/json/read/byte_to_char.rs
@@ -0,0 +1,132 @@
+// Take a look at the license at the top of the repository in the LICENSE file.
+
+use crate::json::read::internal_reader::InternalReader;
+use std::{
+    error, fmt,
+    io::{Error, Read},
+    str::from_utf8,
+};
+
+pub struct ByteToChar<R> {
+    iter: InternalReader<R>,
+}
+
+impl<R: Read> ByteToChar<R> {
+    #[inline]
+    pub fn new(read: R, buffer_size: usize) -> Result<Self, Error> {
+        Ok(ByteToChar {
+            iter: InternalReader::new(read, buffer_size)?,
+        })
+    }
+
+    fn get_next(&mut self) -> Result<Option<u8>, CharsError> {
+        match self.iter.next() {
+            None => Ok(None),
+            Some(item) => match item {
+                Ok(item) => Ok(Some(item)),
+                Err(err) => Err(CharsError::Other(err)),
+            },
+        }
+    }
+}
+
+impl<R: Read + fmt::Debug> fmt::Debug for ByteToChar<R> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("Filter").field("iter", &self.iter).finish()
+    }
+}
+
+impl<R: Read> Iterator for ByteToChar<R> {
+    type Item = Result<char, CharsError>;
+
+    fn next(&mut self) -> Option<Result<char, CharsError>> {
+        let first_byte = match self.get_next() {
+            Err(err) => return Some(Err(err)),
+            Ok(item) => match item {
+                Some(item) => item,
+                None => return None,
+            },
+        };
+
+        let width = utf8_char_width(first_byte);
+        if width == 1 {
+            return Some(Ok(first_byte as char));
+        }
+        if width == 0 {
+            return Some(Err(CharsError::NotUtf8));
+        }
+        let mut buf = [first_byte, 0, 0, 0];
+        {
+            let mut start = 1;
+            while start < width {
+                let byte = match self.get_next() {
+                    Err(err) => return Some(Err(err)),
+                    Ok(item) => match item {
+                        Some(item) => item,
+                        None => return Some(Err(CharsError::NotUtf8)),
+                    },
+                };
+                buf[start] = byte;
+                start += 1;
+            }
+        }
+        Some(match from_utf8(&buf[..width]).ok() {
+            Some(s) => Ok(s.chars().next().unwrap()),
+            None => Err(CharsError::NotUtf8),
+        })
+    }
+}
+
+fn utf8_char_width(b: u8) -> usize {
+    UTF8_CHAR_WIDTH[b as usize] as usize
+}
+
+// https://tools.ietf.org/html/rfc3629
+static UTF8_CHAR_WIDTH: [u8; 256] = [
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+    1, // 0x1F
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+    1, // 0x3F
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+    1, // 0x5F
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+    1, // 0x7F
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, // 0x9F
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, // 0xBF
+    0, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+    2, // 0xDF
+    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, // 0xEF
+    4, 4, 4, 4, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 0xFF
+];
+
+/// An enumeration of possible errors that can be generated from the `Chars`
+/// adapter.
+#[derive(Debug)]
+pub enum CharsError {
+    /// Variant representing that the underlying stream was read successfully
+    /// but it did not contain valid utf8 data.
+    NotUtf8,
+
+    /// Variant representing that an I/O error occurred.
+    Other(Error),
+}
+
+impl error::Error for CharsError {
+    fn cause(&self) -> Option<&dyn error::Error> {
+        match *self {
+            CharsError::NotUtf8 => None,
+            CharsError::Other(ref e) => e.source(),
+        }
+    }
+}
+
+impl fmt::Display for CharsError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match *self {
+            CharsError::NotUtf8 => "byte stream did not contain valid utf8".fmt(f),
+            CharsError::Other(ref e) => e.fmt(f),
+        }
+    }
+}