Automatically find latest version of pip for assertion

- also remove a redundant version constraint test

tests/test_packaging.py

@@ -76,7 +76,6 @@ def test__get_editable_requirements_for_src_layout():
         assert "user_lib2" in pkg_names
 
 
-@pytest.mark.skipif(sys.version_info < (3, 7), reason="requires python3.7 or higher")
 def test__get_editable_requirements_withpip23():
     with tempfile.TemporaryDirectory() as tempdir:
         _create_venv(tempdir)

tests/test_uploader.py

@@ -1,3 +1,5 @@
+import re
+import subprocess
 import sys
 import contextlib
 import json
@@ -441,6 +443,20 @@ def test__unique_filename(spec_file, expected):
     assert expected == uploader._unique_filename(spec_file, packaging.PEX_PACKER)
 
 
+def get_latest_pip_version() -> str:
+    p = subprocess.Popen("pip index versions pip", shell=True,
+                         stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+    for line in p.stdout.readlines():
+        result = re.match(r"pip \((.+)\)", line.decode("utf-8"))
+        if result:
+            return result.group(1)
+    return None
+
+
+def test_lateste_pip():
+    assert get_latest_pip_version() is not None
+
+
 def test_format_pex_requirements():
     with tempfile.TemporaryDirectory() as tempdir:
         requirements = ["pipdeptree==2.0.0", "six==1.15.0"]
@@ -451,7 +467,8 @@ def test_format_pex_requirements():
             pex_inherit_path="false")
         pex_info = PexInfo.from_pex(f"{tempdir}/out.pex")
         cleaned_requirements = uploader._format_pex_requirements(pex_info)
-        assert ['pip==24.2', 'pipdeptree==2.0.0', 'six==1.15.0'] == cleaned_requirements
+        assert [f'pip=={get_latest_pip_version()}',
+                'pipdeptree==2.0.0', 'six==1.15.0'] == cleaned_requirements
 
 
 @pytest.mark.parametrize("req, expected", [