FIX: `to_table` failed on lists

Summary

Fix for #117 (closed)

Focus

• Performance
• Sufficient test

Test Environment

Run the unit test:

pytest --pdb --pdbcls=IPython.terminal.debugger:TerminalPdb unittests/test_table_converter.py::TableTest::test_list

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src/caosadvancedtools/table_converter.py

@@ -49,32 +49,26 @@ def generate_property_name(prop):
 
 
 def to_table(container):
-    """ creates a table from the records in a container """
+    """Create a table from the records in a container."""
 
     if len(container) == 0:
         raise ValueError("Container is empty")
-    properties = set()
-
-    for rec in container:
-        properties.update([generate_property_name(p)
-                           for p in container[0].get_properties()])
-    df = pd.DataFrame(columns=list(properties))
+        # TODO Why not this? return pd.DataFrame()
     rts = {p.name for p in container[0].parents}
 
-    for ii, rec in enumerate(container):
+    data = []
+    for rec in container:
         if {p.name for p in rec.parents} != rts:
             raise ValueError("Parents differ")
 
+        row_dict = {}
         for prop in rec.get_properties():
             propname = generate_property_name(prop)
-            if isinstance(prop.value, list):
-                if propname not in df:
-                    df[propname] = pd.Series(dtype=object)
-                elif df[propname].dtype != object:
-                    df[propname] = df[propname].astype(object)
-            df.at[ii, propname] = prop.value
-
-    return df
+            row_dict[propname] = prop.value
+        data.append(row_dict)
+    result = pd.DataFrame(data=data)
+
+    return result
 
 
 def from_table(spreadsheet, recordtype):