Add REQUESTED support to install_wheel

src/pip/_internal/operations/install/wheel.py

@@ -292,6 +292,7 @@ def install_unpacked_wheel(
     pycompile=True,  # type: bool
     warn_script_location=True,  # type: bool
     direct_url=None,  # type: Optional[DirectUrl]
+    requested=False,  # type: bool
 ):
     # type: (...) -> None
     """Install a wheel.
@@ -580,6 +581,13 @@ def is_entrypoint_wrapper(name):
         replace(direct_url_file.name, direct_url_path)
         generated.append(direct_url_path)
 
+    # Record the REQUESTED file
+    if requested:
+        requested_path = os.path.join(dest_info_dir, 'REQUESTED')
+        with open(requested_path, "w"):
+            pass
+        generated.append(requested_path)
+
     # Record details of all files installed
     record_path = os.path.join(dest_info_dir, 'RECORD')
     with open(record_path, **csv_io_kwargs('r')) as record_file:
@@ -604,6 +612,7 @@ def install_wheel(
     warn_script_location=True,  # type: bool
     _temp_dir_for_testing=None,  # type: Optional[str]
     direct_url=None,  # type: Optional[DirectUrl]
+    requested=False,  # type: bool
 ):
     # type: (...) -> None
     with TempDirectory(
@@ -619,4 +628,5 @@ def install_wheel(
             pycompile=pycompile,
             warn_script_location=warn_script_location,
             direct_url=direct_url,
+            requested=requested,
         )

tests/unit/test_wheel.py

@@ -264,6 +264,19 @@ def test_std_install(self, data, tmpdir):
         )
         self.assert_installed()
 
+    def test_std_install_requested(self, data, tmpdir):
+        self.prep(data, tmpdir)
+        wheel.install_wheel(
+            self.name,
+            self.wheelpath,
+            scheme=self.scheme,
+            req_description=str(self.req),
+            requested=True,
+        )
+        self.assert_installed()
+        requested_path = os.path.join(self.dest_dist_info, 'REQUESTED')
+        assert os.path.isfile(requested_path)
+
     def test_std_install_with_direct_url(self, data, tmpdir):
         """Test that install_wheel creates direct_url.json metadata when
         provided with a direct_url argument. Also test that the RECORDS