Test with smaller buffers

 #255

Author: kornelski

src/rewritable_units/mod.rs

@@ -143,7 +143,9 @@ mod test_utils {
                 |c: &[u8]| output.push(c),
             );
 
-            rewriter.write(html).unwrap();
+            for ch in html.chunks(15) {
+                rewriter.write(ch).unwrap();
+            }
             rewriter.end().unwrap();
         }
 

src/rewritable_units/text_decoder.rs

@@ -2,7 +2,7 @@ use crate::base::SharedEncoding;
 use crate::rewriter::RewritingError;
 use encoding_rs::{CoderResult, Decoder, Encoding, UTF_8};
 
-const DEFAULT_BUFFER_LEN: usize = 1024;
+const DEFAULT_BUFFER_LEN: usize = if cfg!(test) { 13 } else { 1024 };
 
 pub(crate) struct TextDecoder {
     encoding: SharedEncoding,