fix: resolve CSV data truncation in save_to_csv by correctly identifying column widths and remove redundant logic in ZWaferParser

tests/test_data_parser.py

@@ -266,20 +266,25 @@ class TestSaveToCsv:
         assert result is not None
         assert "P12345" in result
 
-    def test_csv_has_sensor_headers(self, tmp_path):
-        # Header count is driven by csv_column_count(family), not data width.
-        # P family → 48 sensors; F family → 22 sensors; X family → 80 sensors.
-        cases = [("P", 48), ("F", 22), ("X", 80), ("B", 29)]
-        for family, expected_cols in cases:
-            data = [["25.0", "24.5"]]
-            result = save_to_csv(data, family, f"{family}00001", str(tmp_path))
-            assert result is not None, f"save_to_csv returned None for {family}"
-            headers = open(result).readline().strip().split(",")
-            assert (
-                len(headers) == expected_cols
-            ), f"{family}: expected {expected_cols} headers, got {len(headers)}"
-            assert headers[0] == "Sensor1"
-            assert headers[-1] == f"Sensor{expected_cols}"
+    def test_csv_header_wins_when_data_wider_than_display(self, tmp_path):
+        # Header count = max(csv_column_count, data width).
+        # When data has 60 columns and P display is 48, header is 60 — no truncation.
+        data = [[f"{i}.0" for i in range(60)]]
+        result = save_to_csv(data, "P", "P00001", str(tmp_path))
+        assert result is not None
+        headers = open(result).readline().strip().split(",")
+        assert len(headers) == 60, f"data width 60 should win over display 48"
+        assert headers[0] == "Sensor1"
+        assert headers[-1] == "Sensor60"
+
+    def test_csv_uses_display_count_when_data_is_narrower(self, tmp_path):
+        # When data has fewer columns than the display count, pad to display.
+        data = [["25.0"]]
+        result = save_to_csv(data, "X", "X00001", str(tmp_path))
+        assert result is not None
+        headers = open(result).readline().strip().split(",")
+        # X display = 80, data = 1 → headers = 80
+        assert len(headers) == 80
 
     def test_csv_row_count_matches_data(self, tmp_path):
         data = [["25.0"], ["24.5"], ["23.0"]]
@@ -302,3 +307,18 @@ class TestSaveToCsv:
         data = [["25.0"]]
         result = save_to_csv(data, "P", "P00001", "/\x00invalid\x00path")
         assert result is None
+
+    def test_preserves_all_columns_when_data_wider_than_display(self, tmp_path):
+        # Bug fix: when data has more columns than csv_column_count(family),
+        # all data columns must be preserved (no silent truncation).
+        data = [[f"{i}.0" for i in range(244)]]
+        result = save_to_csv(data, "P", "P00001", str(tmp_path))
+        assert result is not None
+        with open(result) as f:
+            lines = f.readlines()
+        headers = lines[0].strip().split(",")
+        data_row = lines[1].strip().split(",")
+        # All 244 columns should be preserved, not truncated to 48
+        assert len(headers) == 244, f"expected 244 cols, got {len(headers)}"
+        assert len(data_row) == 244, f"expected 244 data cols, got {len(data_row)}"
+        assert data_row[243] == "243.0", "last column value must be preserved"