Reword wheel hash details output

This rewords the output to be more like the form of the preceeding
messages.  Additionally the size is added, since we have calculated it
anyway.  The output will now look like:

 Collecting simple==3.0
 Building wheels for collected packages: simple
   Building wheel for simple (setup.py): started
   Building wheel for simple (setup.py): finished with status 'done'
   Created wheel for simple: filename=simple-3.0-py3-none-any.whl size=1138 sha256=2a980a802c9d38a24d29aded2dc2df2b080e58370902e5fdf950090ff67aec10
   Stored in directory: /tmp/pytest-of-iwienand/pytest-0/test_pip_wheel_success0/workspace/scratch
 Successfully built simple

A match for the following line is added to the functional test too.

src/pip/_internal/wheel.py

@@ -892,10 +892,12 @@ def _build_one_inside_env(self, req, output_dir, python_tag=None):
                 wheel_name = os.path.basename(wheel_path)
                 dest_path = os.path.join(output_dir, wheel_name)
                 try:
-                    wheel_hash, _ = hash_file(wheel_path)
+                    wheel_hash, length = hash_file(wheel_path)
                     shutil.move(wheel_path, dest_path)
-                    logger.info('Finished: %s sha256=%s',
-                                wheel_name, wheel_hash.hexdigest())
+                    logger.info('Created wheel for %s: '
+                                'filename=%s size=%d sha256=%s',
+                                req.name, wheel_name, length,
+                                wheel_hash.hexdigest())
                     logger.info('Stored in directory: %s', output_dir)
                     return dest_path
                 except Exception:

tests/functional/test_wheel.py

@@ -50,8 +50,11 @@ def test_pip_wheel_success(script, data):
     wheel_file_name = 'simple-3.0-py%s-none-any.whl' % pyversion[0]
     wheel_file_path = script.scratch / wheel_file_name
     assert re.search(
-        "Finished: %s sha256=[A-Fa-f0-9]{64}" % re.escape(wheel_file_name),
-        result.stdout)
+        r"Created wheel for simple: "
+        r"filename=%s size=\d+ sha256=[A-Fa-f0-9]{64}"
+        % re.escape(wheel_file_name), result.stdout)
+    assert re.search(
+        r"^\s+Stored in directory: ", result.stdout, re.M)
     assert wheel_file_path in result.files_created, result.stdout
     assert "Successfully built simple" in result.stdout, result.stdout