Bugfix for parsekit.read: when filling the buffer, the read offset was not taken into account for determining how many bytes could be read.

read/read.go

@@ -126,7 +126,6 @@ func (buf *Buffer) RuneAt(offset int) (rune, int, error) {
 		return utf8.RuneError, 0, buf.err
 	}
 	r, w := utf8.DecodeRune(buf.buffer[buf.start+offset:])
-
 	return r, w, nil
 }
 
@@ -166,7 +165,8 @@ func (buf *Buffer) fill(minBytes int) {
 	// This is more efficient than only filling the data up to the point where
 	// we can read the data at the 'minBytes' position. Ideally, the buffer is
 	// filled completely with data to work with.
-	for buf.len < buf.cap {
+	availableLen := buf.cap - buf.start
+	for buf.len < availableLen {
 		// Read bytes from our source, and append them to the end of the
 		// current buffer data.
 		n, err := buf.bufio.Read(buf.buffer[buf.len:buf.cap])
@@ -193,6 +193,7 @@ func (buf *Buffer) grow(minBytes int) {
 	if buf.start > 0 && minBytes <= buf.cap {
 		copy(buf.buffer, buf.buffer[buf.start:buf.start+buf.len])
 		buf.start = 0
+		return
 	}
 
 	// Grow the buffer store by allocating a new one and copying the data.