added some coverage

src/safeds/data/tabular/containers/_time_series.py

@@ -277,9 +277,8 @@ def add_column(self, column: Column) -> TimeSeries:
         ColumnSizeError
             If the size of the column does not match the number of rows.
         """
-        new_tagged_table = super().add_column(column)
         return TimeSeries._from_tagged_table(
-            new_tagged_table,
+            super().add_column(column),
             time_name=self.time.name,
         )
 
@@ -542,6 +541,7 @@ def remove_columns_with_missing_values(self) -> TimeSeries:
         if len(set(self.features.column_names).intersection(set(table.column_names))) == 0:
             raise IllegalSchemaModificationError("You cannot remove every feature column.")
         if self.time.name not in table.column_names:
+            print("hi")
             raise ColumnIsTimeError(self.time.name)
         return TimeSeries._from_tagged_table(
             TaggedTable._from_table(

tests/safeds/data/tabular/containers/_table/_tagged_table/_time_series/test_add_columns_as_features.py

@@ -53,8 +53,6 @@ def test_add_columns_as_features(
     columns: list[Column] | Table,
     time_series_with_new_columns: TimeSeries,
 ) -> None:
-    print(time_series.add_columns_as_features(columns).features.column_names)
-    print(time_series_with_new_columns.features.column_names)
     assert_that_time_series_are_equal(time_series.add_columns_as_features(columns), time_series_with_new_columns)
 @pytest.mark.parametrize(
     ("time_series", "columns", "error_msg"),

tests/safeds/data/tabular/containers/_table/_tagged_table/_time_series/test_remove_columns.py

@@ -1,6 +1,6 @@
 import pytest
 from safeds.data.tabular.containers import Table, TimeSeries
-from safeds.exceptions import ColumnIsTargetError, IllegalSchemaModificationError
+from safeds.exceptions import ColumnIsTargetError, IllegalSchemaModificationError, ColumnIsTimeError
 
 from tests.helpers import assert_that_time_series_are_equal
 
@@ -199,12 +199,24 @@ def test_should_remove_columns(table: TimeSeries, columns: list[str], expected:
             IllegalSchemaModificationError,
             r"Illegal schema modification: You cannot remove every feature column.",
         ),
+        (
+            TimeSeries._from_table_to_time_series(
+                Table({"time": [0, 1, 2], "feat": [1, 2, 3], "non_feat": [1, 2, 3], "target": [4, 5, 6]}),
+                "target",
+                "time",
+                ["feat"],
+            ),
+            ["time"],
+            ColumnIsTimeError,
+            r'Illegal schema modification: Column "time" is the time column and cannot be removed.',
+        ),
     ],
     ids=[
         "remove_only_target",
         "remove_non_feat_and_target",
         "remove_all_features",
         "remove_non_feat_and_all_features",
+        "remove_time_column",
     ],
 )
 def test_should_raise_in_remove_columns(

tests/safeds/data/tabular/containers/_table/_tagged_table/_time_series/test_remove_columns_with_missing_values.py

@@ -143,7 +143,7 @@ def test_should_remove_columns_with_non_numerical_values(table: TimeSeries, expe
                 {
                     "time": [0, 1, 2],
                     "feature": [0, 1, 2],
-                    "non_feature": [1, None, 3],
+                    "non_feature": [1, 2, 3],
                     "target": [3, 4, None],
                 },
                 "target",
@@ -219,3 +219,4 @@ def test_should_raise_in_remove_columns_with_missing_values(
         match=error_msg,
     ):
         table.remove_columns_with_missing_values()
+

tests/safeds/data/tabular/containers/_table/_tagged_table/_time_series/test_remove_rows_with_missing_values.py

@@ -53,3 +53,4 @@
 def test_should_remove_rows_with_missing_values(table: TimeSeries, expected: TimeSeries) -> None:
     new_table = table.remove_rows_with_missing_values()
     assert_that_time_series_are_equal(new_table, expected)
+