Added translator config file (.pyluaconf.yaml)

Author: dmitrii-eremin

.gitignore

@@ -1,5 +1,6 @@
 # User-defined
 .vscode/
+.pyluaconf.yaml
 
 # Byte-compiled / optimized / DLL files
 __pycache__/

__main__.py

@@ -4,6 +4,7 @@
 from pathlib import Path
 import sys
 
+from pythonlua.config import Config
 from pythonlua.translator import Translator
 
 
@@ -13,6 +14,9 @@ def create_arg_parser():
     parser.add_argument("inputfilename", metavar="IF", type=str,
                         help="A python script filename to translate it.",
                         nargs="?", default="")
+    parser.add_argument("configfilename", metavar="CONFIG", type=str,
+                        help="Translator configuration file in yaml format.",
+                        nargs="?", default=".pyluaconf.yaml")
 
     parser.add_argument("--show-ast", help="Print python ast tree before code.",
                         dest="show_ast", action="store_true")
@@ -47,8 +51,9 @@ def main():
     if not content:
         raise RuntimeError("The input file is empty.")
 
-    translator = Translator(show_ast=argv.show_ast)
-    lua_code = translator.translate(content)    
+    translator = Translator(Config(argv.configfilename),
+                            show_ast=argv.show_ast)
+    lua_code = translator.translate(content)
 
     if not argv.only_lua_init:
         print(lua_code)

pythonlua/config.py

@@ -1,7 +1,30 @@
 """Python to lua translator config class"""
-
+import sys
+import yaml
 
 class Config:
     """Translator config."""
-    def __init__(self):
-        pass
+    def __init__(self, filename=None):
+        self.data = {
+            "class": {
+                "return_at_the_end": False,
+            },
+        }
+
+        if filename is not None:
+            self.load(filename)
+
+    def load(self, filename):
+        """Load config from the file"""
+        try:
+            with open(filename, "r") as stream:
+                data = yaml.load(stream)
+                self.data.update(data)
+        except FileNotFoundError:
+            pass # Use a default config if the file not found
+        except yaml.YAMLError as ex:
+            print(ex)
+
+    def __getitem__(self, key):
+        """Get data values"""
+        return self.data[key]

pythonlua/nodevisitor.py

@@ -16,8 +16,9 @@ class NodeVisitor(ast.NodeVisitor):
     LUACODE = "[[luacode]]"
 
     """Node visitor"""
-    def __init__(self, context=None):
+    def __init__(self, context=None, config=None):
         self.context = context if context is not None else Context()
+        self.config = config
         self.last_end_mode = TokenEndMode.LINE_FEED
         self.output = []
 
@@ -135,6 +136,11 @@ def visit_ClassDef(self, node):
 
         self.emit("end, {{{}}})".format(", ".join(bases)))
 
+        # Return class object only in the top-level classes.
+        # Not in the nested classes.
+        if self.config["class"]["return_at_the_end"] and not last_ctx["class_name"]:
+            self.emit("return {}".format(name))
+
     def visit_Compare(self, node):
         """Visit compare"""
 
@@ -556,7 +562,7 @@ def visit_all(self, nodes, inline=False):
             last_ctx = self.context.last()
             last_ctx["locals"].push()
 
-        visitor = NodeVisitor(self.context)
+        visitor = NodeVisitor(context=self.context, config=self.config)
 
         if isinstance(nodes, list):
             for node in nodes:

pythonlua/translator.py

@@ -9,7 +9,7 @@
 class Translator:
     """Python to lua main class translator"""
     def __init__(self, config=None, show_ast=False):
-        config = config if config is not None else Config()
+        self.config = config if config is not None else Config()
         self.show_ast = show_ast
 
         self.output = []
@@ -18,7 +18,7 @@ def translate(self, pycode):
         """Translate python code to lua code"""
         py_ast_tree = ast.parse(pycode)
 
-        visitor = NodeVisitor()
+        visitor = NodeVisitor(config=self.config)
 
         if self.show_ast:
             print(ast.dump(py_ast_tree))

requirements.txt

@@ -1 +1,2 @@
 colorama==0.3.7
+PyYAML==3.12