Update generator.py

-improved readability
-files now build in the order they appear instead of reverse
-added "with" statements for error handling

generator/generator.py

@@ -2,36 +2,42 @@
 import os
 import re
 
+def read_dbc(filename):
+  with open(os.path.join(dir_name, filename), 'r') as file_in:
+    return file_in.read()
+
 cur_path = os.path.dirname(os.path.realpath(__file__))
 generator_path = os.path.join(cur_path, '../')
 
-for dir_name, _, _ in os.walk(cur_path):
-    if dir_name == cur_path:
-        continue
+include_pattern = r'CM_ "IMPORT (.*?)"'
 
-    print dir_name
+for dir_name, _, filenames in os.walk(cur_path):
+  if dir_name == cur_path:
+    continue
 
-    for filename in os.listdir(dir_name):
-        if filename.startswith('_'):
-            continue
+  print dir_name
 
-        print filename
-        dbc_file = open(os.path.join(dir_name, filename)).read()
-        dbc_file = '\nCM_ "%s starts here"\n' % filename + dbc_file
+  for filename in filenames:
+    if filename.startswith('_'):
+      continue
 
-        includes = re.finditer(r'CM_ "IMPORT (.*?)"', dbc_file)
-        for include in includes:
-            dbc_file = dbc_file.replace(include.group(0), '')
-            include_path = os.path.join(dir_name, include.group(1))
+    print filename
+    dbc_file_in = read_dbc(filename) 
 
-            # Load included file
-            include_file = open(include_path).read()
-            include_file = '\n\nCM_ "Imported file %s starts here"\n' % include.group(1) + include_file
-            dbc_file = include_file + dbc_file
+    includes = re.findall(include_pattern, dbc_file_in)
+ 
+    output_filename = filename.replace('.dbc', '_generated.dbc')
 
-        dbc_file = 'CM_ "AUTOGENERATED FILE, DO NOT EDIT"\n' + dbc_file
+    with open(os.path.join(generator_path, output_filename), 'a') as dbc_file_out:
+      dbc_file_out.write('CM_ "AUTOGENERATED FILE, DO NOT EDIT"\n')
 
-        output_filename = filename.replace('.dbc', '_generated.dbc')
-        output_dbc_file = open(os.path.join(generator_path, output_filename), 'w')
-        output_dbc_file.write(dbc_file)
-        output_dbc_file.close()
+      for include_filename in reversed(includes):
+
+        include_file_header = '\n\nCM_ "Imported file %s starts here"\n' % include_filename
+        dbc_file_out.write(include_file_header)
+
+        include_file = read_dbc(include_filename)
+        dbc_file_out.write(include_file)
+
+      dbc_file_out.write('\nCM_ "%s starts here"\n' % filename)
+      dbc_file_out.write(dbc_file_in)