fix: use data stream comparision for IGES to resolve macOS line wrapping issues

Author: kshitij-maths

tests/test_ffdcad.py

@@ -10,25 +10,42 @@
 from pygem.cad import CADDeformation
 
 
-
 class TestFFDCAD(TestCase):
 
+    def extract_floats(self, lines):
+        """
+        Extract all numeric values from IGES file content.
+
+        This helper function parses a list of IGES file lines and returns
+        a flattened numpy array of all floating-point numbers, ignoring
+        line breaks, empty lines, and non-numeric text.
+
+        IGES files often wrap data lines differently on different platforms.
+        By flattening all numeric values into a single array, this function enables reliable numerical comparison of IGES files regardless of
+        line wrapping or minor formatting differences.
+        """
+        all_values = []
+        for line in lines:
+            if not line.strip():
+                continue
+            parts = line.strip().split(',')[:-1]
+            for p in parts:
+                try:
+                    all_values.append(float(p))
+                except ValueError:
+                    pass
+        return np.asarray(all_values)
+
     def test_ffd_iges_pipe_mod_through_files(self):
         ffd = FFD(None,30,30,30,1e-4)
         ffd.read_parameters(
             filename='tests/test_datasets/parameters_test_ffd_iges.prm')
         ffd('tests/test_datasets/test_pipe.iges', 'test_pipe_result.iges')
         with open('test_pipe_result.iges', "r") as created, \
              open('tests/test_datasets/test_pipe_out_true.iges', "r") as reference:
-             ref = [line for line in reference.readlines()[5:] if line.strip()]
-             cre = [line for line in created.readlines()[5:] if line.strip()]
-             if abs(len(ref) - len(cre)) > 1:
-                 self.fail(f"Length mismatch: {len(ref)} vs {len(cre)}")
-            
-             for r_line, c_line in zip(ref, cre):
-                 ref_ = np.asarray(r_line.split(',')[:-1], dtype=float)
-                 cre_ = np.asarray(c_line.split(',')[:-1], dtype=float)
-                 np.testing.assert_array_almost_equal(cre_, ref_, decimal=6)
+             ref_data = self.extract_floats(reference.readlines()[5:])
+             cre_data = self.extract_floats(created.readlines()[5:])
+             np.testing.assert_array_almost_equal(cre_data, ref_data, decimal=6)
         self.addCleanup(os.remove, 'test_pipe_result.iges')
 
     def test_ffd_iges_pipe_mod_through_topods_shape(self):
@@ -41,15 +58,9 @@ def test_ffd_iges_pipe_mod_through_topods_shape(self):
         CADDeformation.write_shape('test_pipe_hollow_result.iges', mod_shape)
         with open('test_pipe_hollow_result.iges', "r") as created, \
              open('tests/test_datasets/test_pipe_hollow_out_true.iges', "r") as reference:
-             ref = [line for line in reference.readlines()[5:] if line.strip()]
-             cre = [line for line in created.readlines()[5:] if line.strip()]
-             if abs(len(ref) - len(cre)) > 1:
-                 self.fail(f"Length mismatch: {len(ref)} vs {len(cre)}")
-            
-             for r_line, c_line in zip(ref, cre):
-                 ref_ = np.asarray(r_line.split(',')[:-1], dtype=float)
-                 cre_ = np.asarray(c_line.split(',')[:-1], dtype=float)
-                 np.testing.assert_array_almost_equal(cre_, ref_, decimal=6)
+             ref_data = self.extract_floats(reference.readlines()[5:])
+             cre_data = self.extract_floats(created.readlines()[5:])
+             np.testing.assert_array_almost_equal(cre_data, ref_data, decimal=6)
         self.addCleanup(os.remove, 'test_pipe_hollow_result.iges')
 
     """
@@ -68,5 +79,4 @@ def test_ffd_step_pipe_mod_through_files(self):
                  cre_ = np.asarray(re.findall(r"[+-]? *(?:\d+(?:\.\d*)?|\.\d+)(?:[eE][+-]?\d+)?", cre[i]),dtype=float)
                  np.testing.assert_array_almost_equal(cre_, ref_, decimal=6)
         self.addCleanup(os.remove, 'test_pipe_result.step')
-    """
-
+    """