From 41c2f0c9d2b72037edec5a03c275967d147c7102 Mon Sep 17 00:00:00 2001
From: Lars Reimann <mail@larsreimann.com>
Date: Mon, 27 Mar 2023 21:46:24 +0200
Subject: [PATCH] feat: `sort_rows` of a `Table`

---
 src/safeds/data/tabular/containers/_table.py  | 53 +++++++++++++------
 .../containers/_table/test_sort_rows.py       | 25 +++++++++
 2 files changed, 63 insertions(+), 15 deletions(-)
 create mode 100644 tests/safeds/data/tabular/containers/_table/test_sort_rows.py

diff --git a/src/safeds/data/tabular/containers/_table.py b/src/safeds/data/tabular/containers/_table.py
index 2ff97c833..3f539862e 100644
--- a/src/safeds/data/tabular/containers/_table.py
+++ b/src/safeds/data/tabular/containers/_table.py
@@ -272,7 +272,7 @@ def get_column(self, column_name: str) -> Column:
         if self._schema.has_column(column_name):
             output_column = Column(
                 self._data.iloc[
-                    :, [self._schema._get_column_index_by_name(column_name)]
+                :, [self._schema._get_column_index_by_name(column_name)]
                 ].squeeze(),
                 column_name,
                 self._schema.get_type_of_column(column_name),
@@ -853,24 +853,24 @@ def slice(
 
     def sort_columns(
         self,
-        query: Callable[[Column, Column], int] = lambda col1, col2: (
-            col1.name > col2.name
-        )
-        - (col1.name < col2.name),
+        sorter: Callable[[Column, Column], int] =
+        lambda col1, col2: (col1.name > col2.name) - (col1.name < col2.name),
     ) -> Table:
         """
-        Sort a table with the given lambda function.
-        If no function is given the columns will be sorted alphabetically.
-        This function uses the default python sort algorithm.
-        The query returns
-        0, if both columns are equal.
-        < 0, if the first column should be ordered after the second column.
-        > 0, if the first column should be ordered before the second column.
+        Sort the columns of a `Table` with the given sorter and return a new `Table`. The original table is not
+        modified.
+
+        The sorter is a function that takes two columns `col1` and `col2` and returns an integer. If `col1` should be
+        ordered before `col2`, the function should return a negative number. If `col1` should be ordered after `col2`,
+        the function should return a positive number. If the original order of `col1` and `col2` should be kept, the
+        function should return 0.
+
+        If no sorter is given, the columns will be sorted alphabetically by their name.
 
         Parameters
         ----------
-        query : a lambda function
-            The lambda function used to sort the columns.
+        sorter : Callable[[Column, Column], int]
+            The function used to sort the columns.
 
         Returns
         -------
@@ -878,9 +878,32 @@ def sort_columns(
             A new table with sorted columns.
         """
         columns = self.to_columns()
-        columns.sort(key=functools.cmp_to_key(query))
+        columns.sort(key=functools.cmp_to_key(sorter))
         return Table.from_columns(columns)
 
+    def sort_rows(self, sorter: Callable[[Row, Row], int]) -> Table:
+        """
+        Sort the rows of a `Table` with the given sorter and return a new `Table`. The original table is not modified.
+
+        The sorter is a function that takes two rows `row1` and `row2` and returns an integer. If `row1` should be
+        ordered before `row2`, the function should return a negative number. If `row1` should be ordered after `row2`,
+        the function should return a positive number. If the original order of `row1` and `row2` should be kept, the
+        function should return 0.
+
+        Parameters
+        ----------
+        sorter : Callable[[Row, Row], int]
+            The function used to sort the rows.
+
+        Returns
+        -------
+        new_table : Table
+            A new table with sorted rows.
+        """
+        rows = self.to_rows()
+        rows.sort(key=functools.cmp_to_key(sorter))
+        return Table.from_rows(rows)
+
     def split(self, percentage_in_first: float) -> typing.Tuple[Table, Table]:
         """
         Split the table into two new tables.
diff --git a/tests/safeds/data/tabular/containers/_table/test_sort_rows.py b/tests/safeds/data/tabular/containers/_table/test_sort_rows.py
new file mode 100644
index 000000000..32c2e12f8
--- /dev/null
+++ b/tests/safeds/data/tabular/containers/_table/test_sort_rows.py
@@ -0,0 +1,25 @@
+from typing import Callable
+
+import pytest
+
+from safeds.data.tabular.containers import Table, Row, Column
+
+
+@pytest.mark.parametrize(
+    ("table", "sorter", "expected"),
+    [
+        # Activate when https://github.com/Safe-DS/Stdlib/issues/75 is fixed.
+        # (
+        #     Table.from_columns([Column([], "col1")]),
+        #     lambda row1, row2: row1["col1"] - row2["col1"],
+        #     Table.from_columns([Column([], "col1")])
+        # ),
+        (
+            Table.from_columns([Column([3, 2, 1], "col1")]),
+            lambda row1, row2: row1["col1"] - row2["col1"],
+            Table.from_columns([Column([1, 2, 3], "col1")])
+        ),
+    ]
+)
+def test_sort_rows(table: Table, sorter: Callable[[Row, Row], int], expected: Table) -> None:
+    assert table.sort_rows(sorter) == expected