Merge pull request #4989 from pradyunsg/misc/better-pep-518-message

Improve message when setuptools is missing (PEP 518)

src/pip/_internal/operations/prepare.py

@@ -128,9 +128,13 @@ def prep_for_dist(self, finder, build_isolation):
 
         if 'setuptools' not in build_requirements:
             logger.warning(
-                "This version of pip does not implement PEP 516, so "
-                "it cannot build a wheel without setuptools. You may need to "
-                "upgrade to a newer version of pip.")
+                "%s does not include 'setuptools' as a buildtime requirement "
+                "in its pyproject.toml.", self.req.name,
+            )
+            logger.warning(
+                "This version of pip does not implement PEP 517 so it cannot "
+                "build a wheel without setuptools."
+            )
 
         if not should_isolate:
             self.req.build_env = NoOpBuildEnvironment(no_clean=False)