test: add tests for component python code

tests/compiler/code/test_python.py

@@ -0,0 +1,54 @@
+from unittest import TestCase
+from pyromaniac.compiler.code.errors import (
+    PythonSyntaxError, PythonRuntimeError
+)
+from pyromaniac.compiler.code.python import Python
+
+
+def execute(
+    code: str, context: dict | None = None, pure: bool = False,
+) -> dict:
+    context = context or {}
+    Python.create(code, pure).execute(context)
+    return context
+
+
+class TestPython(TestCase):
+    def test_empty(self):
+        self.assertEqual(execute(""), {})
+
+    def test_function(self):
+        code = "def foo(): return 42\nnum = foo()"
+        self.assertEqual(execute(code)["num"], 42)
+
+    def test_pure(self):
+        ctx = {"a": 42, "b": 69}
+        self.assertEqual(execute("a + b", ctx, True)["result"], 42 + 69)
+
+    def test_syntax_error(self):
+        self.assertRaisesPythonSyntax("if for: true")
+
+    def test_invalid_pure(self):
+        self.assertRaisesPythonSyntax("", True)
+        self.assertRaisesPythonSyntax("if True: 'hello'", True)
+        self.assertRaisesPythonSyntax("num = 42", True)
+
+    def test_runtime_error(self):
+        self.assertRaisesPythonRuntime("42 + '69'")
+        self.assertRaisesPythonRuntime("raise ValueError()")
+
+    def test_error_pass_through(self):
+        rte = PythonRuntimeError()
+        raised = self.assertRaisesPythonRuntime("raise e", {"e": rte})
+        self.assertIs(rte, raised)
+
+    def assertRaisesPythonSyntax(self, code: str, pure: bool = False):
+        with self.assertRaises(PythonSyntaxError):
+            Python.create(code, pure)
+
+    def assertRaisesPythonRuntime(
+        self, code: str, context: dict = None, pure: bool = False
+    ) -> Exception:
+        with self.assertRaises(PythonRuntimeError) as e:
+            execute(code, context, pure)
+        return e.exception