fix: parse files with '\r' symbols as line ending correctly

src/stream.cpp

@@ -262,7 +262,24 @@ char Stream::get() {
   AdvanceCurrent();
   m_mark.column++;
 
-  if (ch == '\n') {
+  // if line ending symbol is unknown, set it to the first
+  // encountered line ending.
+  // if line ending '\r' set ending symbol to '\r'
+  // other wise set it to '\n'
+  if (!m_lineEndingSymbol) {
+    if (ch == '\n') { // line ending is '\n'
+      m_lineEndingSymbol = '\n';
+    } else if (ch == '\r') {
+      auto ch2 = peek();
+      if (ch2 == '\n') { // line ending is '\r\n'
+        m_lineEndingSymbol = '\n';
+      } else { // line ending is '\r'
+        m_lineEndingSymbol = '\r';
+      }
+    }
+  }
+
+  if (ch == m_lineEndingSymbol) {
     m_mark.column = 0;
     m_mark.line++;
   }

src/stream.h

@@ -53,6 +53,7 @@ class Stream {
   Mark m_mark;
 
   CharacterSet m_charSet;
+  char m_lineEndingSymbol{}; // 0 means it is not determined yet, must be '\n' or '\r'
   mutable std::deque<char> m_readahead;
   unsigned char* const m_pPrefetched;
   mutable size_t m_nPrefetchedAvailable;