agent: Write a simple python hello world Iteration 3

tests/test_hello.py

@@ -1,94 +1,69 @@
-"""Unit tests for hello.py module."""
+"""Tests for hello.py module using pytest."""
 
 import subprocess
-import unittest
 from pathlib import Path
 
+# Module-level constants to avoid duplication across test functions
+HELLO_SCRIPT = Path(__file__).parent.parent / "hello.py"
+WORKING_DIR = Path(__file__).parent.parent
 
-class TestHelloOutput(unittest.TestCase):
+
+def run_hello():
+    """Run hello.py and return the subprocess result."""
+    return subprocess.run(
+        ["python3", str(HELLO_SCRIPT)],
+        capture_output=True,
+        text=True,
+        cwd=WORKING_DIR,
+    )
+
+
+class TestHelloOutput:
     """Tests for hello.py output behavior."""
 
-    def setUp(self):
-        """Set up test fixtures."""
-        self.hello_script = Path(__file__).parent.parent / "hello.py"
-        self.working_dir = Path(__file__).parent.parent
-
     def test_hello_prints_expected_message(self):
         """Test that hello.py prints 'Hello, World!' to stdout."""
-        result = subprocess.run(
-            ["python3", str(self.hello_script)],
-            capture_output=True,
-            text=True,
-            cwd=self.working_dir
-        )
-        self.assertIn("Hello, World!", result.stdout)
+        result = run_hello()
+        assert "Hello, World!" in result.stdout
 
     def test_hello_exact_output(self):
         """Test that hello.py output matches exactly (with newline)."""
-        result = subprocess.run(
-            ["python3", str(self.hello_script)],
-            capture_output=True,
-            text=True,
-            cwd=self.working_dir
-        )
-        self.assertEqual(result.stdout.strip(), "Hello, World!")
+        result = run_hello()
+        assert result.stdout.strip() == "Hello, World!"
 
     def test_hello_exit_code_zero(self):
         """Test that hello.py exits with code 0."""
-        result = subprocess.run(
-            ["python3", str(self.hello_script)],
-            capture_output=True,
-            text=True,
-            cwd=self.working_dir
-        )
-        self.assertEqual(result.returncode, 0)
+        result = run_hello()
+        assert result.returncode == 0
 
     def test_hello_no_stderr(self):
         """Test that hello.py produces no stderr output."""
-        result = subprocess.run(
-            ["python3", str(self.hello_script)],
-            capture_output=True,
-            text=True,
-            cwd=self.working_dir
-        )
-        self.assertEqual(result.stderr, "")
+        result = run_hello()
+        assert result.stderr == ""
 
     def test_hello_stdout_not_empty(self):
         """Test that hello.py produces non-empty stdout."""
-        result = subprocess.run(
-            ["python3", str(self.hello_script)],
-            capture_output=True,
-            text=True,
-            cwd=self.working_dir
-        )
-        self.assertTrue(len(result.stdout) > 0)
+        result = run_hello()
+        assert len(result.stdout) > 0
 
 
-class TestHelloFileExists(unittest.TestCase):
+class TestHelloFile:
     """Tests for hello.py file existence and content."""
 
-    def setUp(self):
-        """Set up test fixtures."""
-        self.hello_script = Path(__file__).parent.parent / "hello.py"
-
     def test_hello_file_exists(self):
         """Test that hello.py file exists."""
-        self.assertTrue(self.hello_script.exists())
+        assert HELLO_SCRIPT.exists()
 
     def test_hello_file_is_python(self):
         """Test that hello.py has .py extension."""
-        self.assertEqual(self.hello_script.suffix, ".py")
+        assert HELLO_SCRIPT.suffix == ".py"
 
     def test_hello_file_contains_print(self):
         """Test that hello.py contains a print statement."""
-        content = self.hello_script.read_text()
-        self.assertIn("print", content)
+        content = HELLO_SCRIPT.read_text()
+        assert "print" in content
 
     def test_hello_file_contains_hello_world(self):
         """Test that hello.py contains 'Hello, World!' string."""
-        content = self.hello_script.read_text()
-        self.assertIn("Hello, World!", content)
-
-
-if __name__ == "__main__":
-    unittest.main()
+        content = HELLO_SCRIPT.read_text()
+        assert "Hello, World!" in content