From 6a4eb50722a9f1d4fe4ce07a332df39a680a6cfc Mon Sep 17 00:00:00 2001
From: Magdalena Kowalczuk <74981211+anopsy@users.noreply.github.com>
Date: Wed, 7 Aug 2024 07:34:21 +0000
Subject: [PATCH 1/2] add DaskExpr-count and DaskExpr-drop-nulls formatted

---
 narwhals/_dask/expr.py                   | 12 ++++++++++++
 tests/expr_and_series/drop_nulls_test.py |  6 +-----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/narwhals/_dask/expr.py b/narwhals/_dask/expr.py
index 1ad1e0778..180f4d1ce 100644
--- a/narwhals/_dask/expr.py
+++ b/narwhals/_dask/expr.py
@@ -267,11 +267,23 @@ def sum(self) -> Self:
             "sum",
         )
 
+    def count(self) -> Self:
+        return self._from_call(
+            lambda _input: _input.count(),
+            "count",
+        )
+
     def round(self, decimals: int) -> Self:
         return self._from_call(
             lambda _input, decimals: _input.round(decimals), "round", decimals
         )
 
+    def drop_nulls(self) -> Self:
+        return self._from_call(
+            lambda _input: _input.dropna(),
+            "drop_nulls",
+        )
+
     def fill_null(self, value: Any) -> DaskExpr:
         return self._from_call(lambda _input, _val: _input.fillna(_val), "fillna", value)
 
diff --git a/tests/expr_and_series/drop_nulls_test.py b/tests/expr_and_series/drop_nulls_test.py
index 26455615d..5e54e8175 100644
--- a/tests/expr_and_series/drop_nulls_test.py
+++ b/tests/expr_and_series/drop_nulls_test.py
@@ -2,15 +2,11 @@
 
 from typing import Any
 
-import pytest
-
 import narwhals as nw
 from tests.utils import compare_dicts
 
 
-def test_drop_nulls(constructor: Any, request: Any) -> None:
-    if "dask" in str(constructor):
-        request.applymarker(pytest.mark.xfail)
+def test_drop_nulls(constructor: Any) -> None:
     data = {
         "A": [1, 2, None, 4],
         "B": [5, 6, 7, 8],

From 59f174c90bb09c4e2f88a7a01a99aa5b00139b90 Mon Sep 17 00:00:00 2001
From: Magdalena Kowalczuk <74981211+anopsy@users.noreply.github.com>
Date: Thu, 8 Aug 2024 11:15:23 +0000
Subject: [PATCH 2/2] add dask Expr.count

---
 narwhals/_dask/expr.py                   | 7 +------
 tests/expr_and_series/count_test.py      | 6 +-----
 tests/expr_and_series/drop_nulls_test.py | 6 +++++-
 3 files changed, 7 insertions(+), 12 deletions(-)

diff --git a/narwhals/_dask/expr.py b/narwhals/_dask/expr.py
index 421eb9c31..e2a7438e4 100644
--- a/narwhals/_dask/expr.py
+++ b/narwhals/_dask/expr.py
@@ -297,6 +297,7 @@ def count(self) -> Self:
         return self._from_call(
             lambda _input: _input.count(),
             "count",
+            returns_scalar=True,
         )
 
     def round(self, decimals: int) -> Self:
@@ -307,12 +308,6 @@ def round(self, decimals: int) -> Self:
             returns_scalar=False,
         )
 
-    def drop_nulls(self) -> Self:
-        return self._from_call(
-            lambda _input: _input.dropna(),
-            "drop_nulls",
-        )
-
     def fill_null(self, value: Any) -> DaskExpr:
         return self._from_call(
             lambda _input, _val: _input.fillna(_val),
diff --git a/tests/expr_and_series/count_test.py b/tests/expr_and_series/count_test.py
index 10feff5d9..208df3bc1 100644
--- a/tests/expr_and_series/count_test.py
+++ b/tests/expr_and_series/count_test.py
@@ -1,14 +1,10 @@
 from typing import Any
 
-import pytest
-
 import narwhals.stable.v1 as nw
 from tests.utils import compare_dicts
 
 
-def test_count(constructor: Any, request: Any) -> None:
-    if "dask" in str(constructor):
-        request.applymarker(pytest.mark.xfail)
+def test_count(constructor: Any) -> None:
     data = {"a": [1, 3, 2], "b": [4, None, 6], "z": [7.0, None, None]}
     df = nw.from_native(constructor(data))
     result = df.select(nw.col("a", "b", "z").count())
diff --git a/tests/expr_and_series/drop_nulls_test.py b/tests/expr_and_series/drop_nulls_test.py
index 5e54e8175..26455615d 100644
--- a/tests/expr_and_series/drop_nulls_test.py
+++ b/tests/expr_and_series/drop_nulls_test.py
@@ -2,11 +2,15 @@
 
 from typing import Any
 
+import pytest
+
 import narwhals as nw
 from tests.utils import compare_dicts
 
 
-def test_drop_nulls(constructor: Any) -> None:
+def test_drop_nulls(constructor: Any, request: Any) -> None:
+    if "dask" in str(constructor):
+        request.applymarker(pytest.mark.xfail)
     data = {
         "A": [1, 2, None, 4],
         "B": [5, 6, 7, 8],