SNOW-1842839: Add support for Series.str.pad (#2739)

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   Fixes SNOW-1842839

2. Fill out the following pre-review checklist:

- [x] I am adding a new automated test(s) to verify correctness of my
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- [ ] If this test skips Local Testing mode, I'm requesting review from
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3. Please describe how your code solves the related issue.

   Add support for Series.str.pad.

CHANGELOG.md

@@ -8,6 +8,7 @@
 
 - Added support for `Series.str.ljust` and `Series.str.rjust`.
 - Added support for `Series.str.center`.
+- Added support for `Series.str.pad`.
 
 
 ## 1.26.0 (2024-12-05)

docs/source/modin/supported/series_str_supported.rst

@@ -89,7 +89,7 @@ the method in the left column.
 +-----------------------------+---------------------------------+----------------------------------------------------+
 | ``normalize``               | N                               |                                                    |
 +-----------------------------+---------------------------------+----------------------------------------------------+
-| ``pad``                     | N                               |                                                    |
+| ``pad``                     | Y                               |                                                    |
 +-----------------------------+---------------------------------+----------------------------------------------------+
 | ``partition``               | N                               |                                                    |
 +-----------------------------+---------------------------------+----------------------------------------------------+

src/snowflake/snowpark/modin/plugin/compiler/snowflake_query_compiler.py

@@ -16260,7 +16260,7 @@ def str_center(self, width: int, fillchar: str = " ") -> "SnowflakeQueryCompiler
             )
         if not isinstance(fillchar, str):
             raise TypeError(
-                f"fillchar must be of integer type, not {type(fillchar).__name__}"
+                f"fillchar must be a character, not {type(fillchar).__name__}"
             )
         if len(fillchar) != 1:
             raise TypeError("fillchar must be a character, not str")
@@ -16443,8 +16443,15 @@ def str_pad(
         width: int,
         side: Literal["left", "right", "both"] = "left",
         fillchar: str = " ",
-    ) -> None:
-        ErrorMessage.method_not_implemented_error("pad", "Series.str")
+    ) -> "SnowflakeQueryCompiler":
+        if side == "left":
+            return self.str_rjust(width, fillchar)
+        elif side == "right":
+            return self.str_ljust(width, fillchar)
+        elif side == "both":
+            return self.str_center(width, fillchar)
+        else:
+            raise ValueError("Invalid side")
 
     def str_partition(self, sep: str = " ", expand: bool = True) -> None:
         ErrorMessage.method_not_implemented_error("partition", "Series.str")
@@ -16506,7 +16513,7 @@ def str_ljust(self, width: int, fillchar: str = " ") -> "SnowflakeQueryCompiler"
             )
         if not isinstance(fillchar, str):
             raise TypeError(
-                f"fillchar must be of integer type, not {type(fillchar).__name__}"
+                f"fillchar must be a character, not {type(fillchar).__name__}"
             )
         if len(fillchar) != 1:
             raise TypeError("fillchar must be a character, not str")

src/snowflake/snowpark/modin/plugin/docstrings/series_utils.py

@@ -334,7 +334,56 @@ def replace():
         """
 
     def pad():
-        pass
+        """
+        Pad strings in the Series/Index up to width.
+
+        Parameters
+        ----------
+        width : int
+            Minimum width of resulting string; additional characters will be filled with character defined in fillchar.
+        side : {‘left’, ‘right’, ‘both’}, default ‘left’
+            Side from which to fill resulting string.
+        fillchar : str, default ‘ ‘
+            Additional character for filling, default is whitespace.
+        Returns
+        -------
+        Series or Index of object
+            Returns Series or Index with minimum number of char in object.
+
+        See also
+        --------
+        Series.str.rjust
+            Fills the left side of strings with an arbitrary character. Equivalent to Series.str.pad(side='left').
+        Series.str.ljust
+            Fills the right side of strings with an arbitrary character. Equivalent to Series.str.pad(side='right').
+        Series.str.center
+            Fills both sides of strings with an arbitrary character. Equivalent to Series.str.pad(side='both').
+        Series.str.zfill
+            Pad strings in the Series/Index by prepending ‘0’ character. Equivalent to Series.str.pad(side='left', fillchar='0').
+
+        Examples
+        --------
+        >>> s = pd.Series(["caribou", "tiger"])
+        >>> s
+        0    caribou
+        1      tiger
+        dtype: object
+
+        >>> s.str.pad(width=10)
+        0       caribou
+        1         tiger
+        dtype: object
+
+        >>> s.str.pad(width=10, side='right', fillchar='-')
+        0    caribou---
+        1    tiger-----
+        dtype: object
+
+        >>> s.str.pad(width=10, side='both', fillchar='-')
+        0    -caribou--
+        1    --tiger---
+        dtype: object
+        """
 
     def center():
         """

tests/integ/modin/series/test_str_accessor.py

@@ -456,6 +456,42 @@ def test_str_center_ljust_rjust_neg(func, width, fillchar):
         getattr(snow_ser.str, func)(width=width, fillchar=fillchar)
 
 
+@pytest.mark.parametrize("width", [-1, 0, 1, 10, 100])
+@pytest.mark.parametrize("side", ["left", "right", "both"])
+@pytest.mark.parametrize("fillchar", [" ", "#"])
+@sql_count_checker(query_count=1)
+def test_str_pad(width, side, fillchar):
+    native_ser = native_pd.Series(TEST_DATA)
+    snow_ser = pd.Series(native_ser)
+    eval_snowpark_pandas_result(
+        snow_ser,
+        native_ser,
+        lambda ser: ser.str.pad(width=width, side=side, fillchar=fillchar),
+    )
+
+
+@pytest.mark.parametrize(
+    "width, side, fillchar, error",
+    [
+        (None, "both", " ", TypeError),
+        ("ten", "both", " ", TypeError),
+        (10, None, " ", ValueError),
+        (10, 10, " ", ValueError),
+        (10, "invalid", " ", ValueError),
+        (10, "both", "", TypeError),
+        (10, "both", "ab", TypeError),
+        (10, "both", None, TypeError),
+        (10, "both", 10, TypeError),
+    ],
+)
+@sql_count_checker(query_count=0)
+def test_str_pad_neg(width, side, fillchar, error):
+    native_ser = native_pd.Series(TEST_DATA)
+    snow_ser = pd.Series(native_ser)
+    with pytest.raises(error):
+        snow_ser.str.pad(width=width, side=side, fillchar=fillchar)
+
+
 @pytest.mark.parametrize(
     "data",
     [

tests/unit/modin/test_series_strings.py

@@ -36,7 +36,6 @@ def test_str_cat_no_others(mock_str_register, mock_series):
         (lambda s: s.str.encode("utf-8"), "encode"),
         (lambda s: s.str.rsplit("_", n=1), "rsplit"),
         (lambda s: s.str.join("_"), "join"),
-        (lambda s: s.str.pad(10), "pad"),
         (lambda s: s.str.zfill(8), "zfill"),
         (lambda s: s.str.wrap(3), "wrap"),
         (lambda s: s.str.slice_replace(start=3, stop=5, repl="abc"), "slice_replace"),
@@ -99,11 +98,6 @@ def test_str_methods_with_dataframe_return(func, func_name, mock_series):
             AttributeError,
             "'NoneType' object has no attribute 'join'",
         ),
-        (
-            lambda s: s.str.pad(8, fillchar="abc"),
-            TypeError,
-            "fillchar must be a character, not str",
-        ),
         (lambda s: s.str.wrap(-1), ValueError, r"invalid width -1 \(must be > 0\)"),
         (
             lambda s: s.str.count(12),