Fix attribute parsing

src/proc.rs

@@ -4,6 +4,7 @@ use phf::Set;
 
 use crate::err::{ErrorType, ProcessingResult};
 use crate::pattern::{SinglePattern, TrieNode};
+use std::io::{stderr, Write};
 
 macro_rules! chain {
     ($proc:ident $($tail:tt)+) => ({
@@ -411,6 +412,9 @@ impl<'d> Processor<'d> {
     // Writing characters directly.
     /// Write `c` to output. Will panic if exceeds bounds.
     pub fn write(&mut self, c: u8) -> () {
+        if self.write_next >= self.code.len() {
+            stderr().write_all(self.code);
+        }
         self.code[self.write_next] = c;
         self.write_next += 1;
     }

src/unit/attr/value.rs

@@ -220,10 +220,10 @@ pub struct ProcessedAttrValue {
 }
 
 pub fn process_attr_value(proc: &mut Processor, should_collapse_and_trim_ws: bool) -> ProcessingResult<ProcessedAttrValue> {
+    let attr_start = proc.checkpoint();
     let src_delimiter = chain!(proc.match_pred(is_attr_quote).require_with_reason("attribute value delimiter quote")?.discard().char());
 
     // Stage 1: read and collect metrics on attribute value characters.
-    let src_value_checkpoint = proc.checkpoint();
     let mut metrics = Metrics {
         count_double_quotation: 0,
         count_single_quotation: 0,
@@ -239,9 +239,13 @@ pub fn process_attr_value(proc: &mut Processor, should_collapse_and_trim_ws: boo
     });
 
     // Stage 2: optimally minify attribute value using metrics.
-    proc.restore(src_value_checkpoint);
+    proc.restore(attr_start);
     // Skip required opening delimiter quote.
-    proc.skip_expect();
+    if cfg!(debug_assertions) {
+        chain!(proc.match_char(src_delimiter).expect().discard());
+    } else {
+        proc.skip_expect();
+    };
     let optimal_delimiter = metrics.get_optimal_delimiter_type();
     let optimal_delimiter_char = match optimal_delimiter {
         DelimiterType::Double => Some(b'"'),
@@ -282,7 +286,7 @@ pub fn process_attr_value(proc: &mut Processor, should_collapse_and_trim_ws: boo
                 _ => proc.write(b'"'),
             },
             // If unquoted, encode right chevron if last character.
-            CharType::RightChevron => if optimal_delimiter == DelimiterType::Unquoted && processing_char_no == metrics.collected_count - 1 {
+            CharType::RightChevron => if optimal_delimiter == DelimiterType::Unquoted && metrics.collected_count > 0 && processing_char_no == metrics.collected_count - 1 {
                 proc.write_slice(ENCODED[&b'>']);
             } else {
                 proc.write(b'>');