move close output stream method to tex formatter

PyTeX/format/simple_tex_formatter.py

@@ -14,9 +14,6 @@ class SimpleTeXFormatter(TexFormatter):
         }
         return self.name + switcher[self.config.tex_type]
 
-    def close_output_stream(self):
-        self._output_file.close()
-
     @property
     def future_config(self) -> List[Tuple[str, FormattingConfig]]:
         return []  # TODO

PyTeX/format/tex_formatter.py

@@ -75,12 +75,8 @@ class TexFormatter(PyTeXFormatter, ABC):
         else:
             self._output_file = out_file.open('w')
 
-    @abstractmethod
     def close_output_stream(self) -> None:
-        """
-
-        :return:
-        """
+        self._output_file.close()
 
     @property
     @abstractmethod
@@ -123,8 +119,14 @@ class TexFormatter(PyTeXFormatter, ABC):
         """
         return line.rstrip()
 
-    def _shipout_line(self, line):
-        self.write_line(line + '\n')
+    def _shipout_line(self, line) -> None:
+        """
+        The line might get dropped according to current mode
+
+        :param line: Line to shipout
+        :return: None
+        """
+        self.write_line(line.rstrip('\n') + '\n')
 
     def write_line(self, line: str):
         if self._output_file is None: