feat(runner): add command-line arguments

main.py

@@ -1,8 +1,31 @@
+#!/usr/bin/python
+
+import argparse
+import os
+from pathlib import Path
+
 from src.runner import Runner
 
 
+def is_valid_file(parser, arg):
+    if not os.path.isfile(arg):
+        parser.error("The file %s does not exist!" % arg)
+        return None
+    return Path(arg)
+
+
 def main():
-    Runner.repl()
+    parser = argparse.ArgumentParser(
+        prog="pebble"
+    )
+    parser.add_argument("script", type=lambda x: is_valid_file(parser, x), help="File to run", nargs="?")
+
+    args = parser.parse_args()
+
+    if args.script is None:
+        Runner.repl()
+    else:
+        Runner.run_file(args.script)
 
 
 if __name__ == '__main__':

src/runner.py

@@ -1,3 +1,4 @@
+from pathlib import Path
 from typing import Optional
 
 from src.ast.stmt import Stmt
@@ -11,12 +12,16 @@ from src.token import Token, TokenType
 
 
 class Runner:
-    def __init__(self, source: str, path: Optional[str] = None):
-        self.source: str = source
-        self.path: Optional[str] = path
+    @staticmethod
+    def run_file(path: Path):
+        with open(path, "r") as f:
+            source: str = f.read()
 
-    def run(self):
-        lexer: Lexer = Lexer(self.source, self.path)
+        Runner.run(source, path)
+
+    @staticmethod
+    def run(source: str, path: Optional[Path] = None):
+        lexer: Lexer = Lexer(source, path)
         tokens: list[Token] = lexer.process()
         print(list(filter(lambda t: t.type not in Parser.IGNORE, tokens)))
 
@@ -75,7 +80,6 @@ class Runner:
                 Pebble.had_error = False
                 continue
 
-
             brace_depth = 0
             paren_depth = 0
             for token in tokens: