diff --git a/tests/masonry/test_api.py b/tests/masonry/test_api.py
index 56b7845c2..9f8cfc95c 100644
--- a/tests/masonry/test_api.py
+++ b/tests/masonry/test_api.py
@@ -4,8 +4,6 @@
 import os
 import platform
 import sys
-import tarfile
-import zipfile
 
 from contextlib import contextmanager
 
@@ -16,6 +14,8 @@
 from poetry.core.utils._compat import Path
 from poetry.core.utils._compat import decode
 from poetry.core.utils.helpers import temporary_directory
+from tests.testutils import validate_sdist_contents
+from tests.testutils import validate_wheel_contents
 
 
 @contextmanager
@@ -46,25 +46,23 @@ def test_get_requires_for_build_sdist():
 def test_build_wheel():
     with temporary_directory() as tmp_dir, cwd(os.path.join(fixtures, "complete")):
         filename = api.build_wheel(tmp_dir)
-
-        with zipfile.ZipFile(str(os.path.join(tmp_dir, filename))) as zip:
-            namelist = zip.namelist()
-
-            assert "my_package-1.2.3.dist-info/entry_points.txt" in namelist
-            assert "my_package-1.2.3.dist-info/WHEEL" in namelist
-            assert "my_package-1.2.3.dist-info/METADATA" in namelist
+        validate_wheel_contents(
+            name="my_package",
+            version="1.2.3",
+            path=str(os.path.join(tmp_dir, filename)),
+            files=["entry_points.txt"],
+        )
 
 
 def test_build_wheel_with_include():
     with temporary_directory() as tmp_dir, cwd(os.path.join(fixtures, "with-include")):
         filename = api.build_wheel(tmp_dir)
-
-        with zipfile.ZipFile(str(os.path.join(tmp_dir, filename))) as zip:
-            namelist = zip.namelist()
-
-            assert "with_include-1.2.3.dist-info/entry_points.txt" in namelist
-            assert "with_include-1.2.3.dist-info/WHEEL" in namelist
-            assert "with_include-1.2.3.dist-info/METADATA" in namelist
+        validate_wheel_contents(
+            name="with_include",
+            version="1.2.3",
+            path=str(os.path.join(tmp_dir, filename)),
+            files=["entry_points.txt"],
+        )
 
 
 @pytest.mark.skipif(
@@ -76,36 +74,31 @@ def test_build_wheel_with_include():
 def test_build_wheel_extended():
     with temporary_directory() as tmp_dir, cwd(os.path.join(fixtures, "extended")):
         filename = api.build_wheel(tmp_dir)
-
         whl = Path(tmp_dir) / filename
         assert whl.exists()
-
-        with zipfile.ZipFile(str(os.path.join(tmp_dir, filename))) as zip:
-            namelist = zip.namelist()
-
-            assert "extended-0.1.dist-info/RECORD" in namelist
-            assert "extended-0.1.dist-info/WHEEL" in namelist
-            assert "extended-0.1.dist-info/METADATA" in namelist
+        validate_wheel_contents(name="extended", version="0.1", path=whl.as_posix())
 
 
 def test_build_sdist():
     with temporary_directory() as tmp_dir, cwd(os.path.join(fixtures, "complete")):
         filename = api.build_sdist(tmp_dir)
-
-        with tarfile.open(str(os.path.join(tmp_dir, filename))) as tar:
-            namelist = tar.getnames()
-
-            assert "my-package-1.2.3/LICENSE" in namelist
+        validate_sdist_contents(
+            name="my-package",
+            version="1.2.3",
+            path=str(os.path.join(tmp_dir, filename)),
+            files=["LICENSE"],
+        )
 
 
 def test_build_sdist_with_include():
     with temporary_directory() as tmp_dir, cwd(os.path.join(fixtures, "with-include")):
         filename = api.build_sdist(tmp_dir)
-
-        with tarfile.open(str(os.path.join(tmp_dir, filename))) as tar:
-            namelist = tar.getnames()
-
-            assert "with-include-1.2.3/LICENSE" in namelist
+        validate_sdist_contents(
+            name="with-include",
+            version="1.2.3",
+            path=str(os.path.join(tmp_dir, filename)),
+            files=["LICENSE"],
+        )
 
 
 def test_prepare_metadata_for_build_wheel():
diff --git a/tests/testutils.py b/tests/testutils.py
index b18ae6a5f..161aed735 100644
--- a/tests/testutils.py
+++ b/tests/testutils.py
@@ -1,10 +1,13 @@
 import shutil
 import subprocess
+import tarfile
+import zipfile
 
 from contextlib import contextmanager
 from typing import Any
 from typing import ContextManager
 from typing import Dict
+from typing import List
 from typing import Optional
 
 from poetry.core.utils._compat import Path
@@ -62,3 +65,24 @@ def subprocess_run(*args, **kwargs):  # type: (str, Any) -> subprocess.Completed
     )
     assert result.returncode == 0
     return result
+
+
+def validate_wheel_contents(
+    name, version, path, files=None
+):  # type: (str, str, str, Optional[List[str]]) -> None
+    dist_info = "{}-{}.dist-info".format(name, version)
+    files = files or []
+
+    with zipfile.ZipFile(path) as z:
+        namelist = z.namelist()
+        for filename in ["WHEEL", "METADATA", "RECORD", *files]:
+            assert "{}/{}".format(dist_info, filename) in namelist
+
+
+def validate_sdist_contents(
+    name, version, path, files
+):  # type: (str, str, str, List[str]) -> None
+    with tarfile.open(path) as tar:
+        namelist = tar.getnames()
+        for filename in files:
+            assert "{}-{}/{}".format(name, version, filename) in namelist