diff --git a/changelog/10230.bugfix.rst b/changelog/10230.bugfix.rst
new file mode 100644
index 00000000000..6ca2b00bf89
--- /dev/null
+++ b/changelog/10230.bugfix.rst
@@ -0,0 +1 @@
+Ignore ``.py`` files created by ``pyproject.toml``-based editable builds introduced in `pip 21.3 <https://pip.pypa.io/en/stable/news/#v21-3>`__.
diff --git a/src/_pytest/config/__init__.py b/src/_pytest/config/__init__.py
index 91ad3f094ff..53f40c24571 100644
--- a/src/_pytest/config/__init__.py
+++ b/src/_pytest/config/__init__.py
@@ -833,7 +833,8 @@ def _iter_rewritable_modules(package_files: Iterable[str]) -> Iterator[str]:
         if is_simple_module:
             module_name, _ = os.path.splitext(fn)
             # we ignore "setup.py" at the root of the distribution
-            if module_name != "setup":
+            # as well as editable installation finder modules made by setuptools
+            if module_name != "setup" and not module_name.startswith("__editable__"):
                 seen_some = True
                 yield module_name
         elif is_package:
diff --git a/src/_pytest/reports.py b/src/_pytest/reports.py
index 725fdf61739..3c58321e706 100644
--- a/src/_pytest/reports.py
+++ b/src/_pytest/reports.py
@@ -455,7 +455,7 @@ def _report_to_json(report: BaseReport) -> Dict[str, Any]:
     def serialize_repr_entry(
         entry: Union[ReprEntry, ReprEntryNative]
     ) -> Dict[str, Any]:
-        data = attr.asdict(entry)
+        data = attr.asdict(entry)  # type:ignore[arg-type]
         for key, value in data.items():
             if hasattr(value, "__dict__"):
                 data[key] = attr.asdict(value)
@@ -463,7 +463,7 @@ def serialize_repr_entry(
         return entry_data
 
     def serialize_repr_traceback(reprtraceback: ReprTraceback) -> Dict[str, Any]:
-        result = attr.asdict(reprtraceback)
+        result = attr.asdict(reprtraceback)  # type:ignore[arg-type]
         result["reprentries"] = [
             serialize_repr_entry(x) for x in reprtraceback.reprentries
         ]
@@ -473,7 +473,7 @@ def serialize_repr_crash(
         reprcrash: Optional[ReprFileLocation],
     ) -> Optional[Dict[str, Any]]:
         if reprcrash is not None:
-            return attr.asdict(reprcrash)
+            return attr.asdict(reprcrash)  # type:ignore[arg-type]
         else:
             return None
 
diff --git a/testing/test_config.py b/testing/test_config.py
index 6784809e097..3653ce47fa3 100644
--- a/testing/test_config.py
+++ b/testing/test_config.py
@@ -837,6 +837,9 @@ def test_confcutdir_check_isdir(self, pytester: Pytester) -> None:
             (["src/bar/__init__.py"], ["bar"]),
             (["src/bar/__init__.py", "setup.py"], ["bar"]),
             (["source/python/bar/__init__.py", "setup.py"], ["bar"]),
+            # editable installation finder modules
+            (["__editable___xyz_finder.py"], []),
+            (["bar/__init__.py", "__editable___xyz_finder.py"], ["bar"]),
         ],
     )
     def test_iter_rewritable_modules(self, names, expected) -> None: