Refactor test_lazy_imports.py to reduce code duplication

- Added _run_in_subprocess helper method to eliminate repetition
- Helper accepts code and fail_map for flexible error handling
- Enhanced error reporting to include both stdout and stderr for better debugging
- All 55 tests still pass

Co-authored-by: 4n4nd <22333506+4n4nd@users.noreply.github.com>

Author: Copilot

tests/test_lazy_imports.py

@@ -7,6 +7,34 @@
 class TestLazyImports(unittest.TestCase):
     """Test that PrometheusConnect can be imported without loading heavy dependencies."""
 
+    def _run_in_subprocess(self, code, fail_map):
+        """Run code in a subprocess and check exit codes against fail_map.
+        
+        Args:
+            code: Python code to execute in subprocess
+            fail_map: Dictionary mapping exit codes to error messages
+            
+        Raises:
+            AssertionError: If subprocess exits with a code in fail_map or any non-zero code
+        """
+        result = subprocess.run(
+            [sys.executable, '-c', code],
+            capture_output=True,
+            text=True
+        )
+        
+        if result.returncode in fail_map:
+            self.fail(fail_map[result.returncode])
+        elif result.returncode != 0:
+            # Include both stdout and stderr for better debugging
+            output = []
+            if result.stdout:
+                output.append(f"stdout: {result.stdout}")
+            if result.stderr:
+                output.append(f"stderr: {result.stderr}")
+            output_str = "\n".join(output) if output else "no output"
+            self.fail(f"Subprocess failed with code {result.returncode}: {output_str}")
+
     def test_prometheus_connect_import_without_pandas_matplotlib_numpy(self):
         """Test that importing PrometheusConnect doesn't load pandas, matplotlib, or numpy."""
         # Run in a subprocess to avoid affecting other tests
@@ -27,20 +55,12 @@ def test_prometheus_connect_import_without_pandas_matplotlib_numpy(self):
     sys.exit(3)
 sys.exit(0)
 """
-        result = subprocess.run(
-            [sys.executable, '-c', code],
-            capture_output=True,
-            text=True
-        )
-        
-        if result.returncode == 1:
-            self.fail("pandas should not be loaded when importing PrometheusConnect")
-        elif result.returncode == 2:
-            self.fail("matplotlib should not be loaded when importing PrometheusConnect")
-        elif result.returncode == 3:
-            self.fail("numpy should not be loaded when importing PrometheusConnect")
-        elif result.returncode != 0:
-            self.fail(f"Subprocess failed with code {result.returncode}: {result.stderr}")
+        fail_map = {
+            1: "pandas should not be loaded when importing PrometheusConnect",
+            2: "matplotlib should not be loaded when importing PrometheusConnect",
+            3: "numpy should not be loaded when importing PrometheusConnect",
+        }
+        self._run_in_subprocess(code, fail_map)
 
     def test_prometheus_connect_instantiation_without_numpy(self):
         """Test that PrometheusConnect can be instantiated without loading numpy."""
@@ -60,18 +80,11 @@ def test_prometheus_connect_instantiation_without_numpy(self):
     sys.exit(2)
 sys.exit(0)
 """
-        result = subprocess.run(
-            [sys.executable, '-c', code],
-            capture_output=True,
-            text=True
-        )
-        
-        if result.returncode == 1:
-            self.fail("numpy should not be loaded when instantiating PrometheusConnect")
-        elif result.returncode == 2:
-            self.fail("PrometheusConnect should be instantiated successfully")
-        elif result.returncode != 0:
-            self.fail(f"Subprocess failed with code {result.returncode}: {result.stderr}")
+        fail_map = {
+            1: "numpy should not be loaded when instantiating PrometheusConnect",
+            2: "PrometheusConnect should be instantiated successfully",
+        }
+        self._run_in_subprocess(code, fail_map)
 
     def test_metric_import_loads_pandas(self):
         """Test that importing Metric does load pandas (expected behavior)."""