Move assert_[not_]installed to Script and use it

This help function is much better than the previous ad-hoc logic used in
test_uninstall.py, which has trouble identifying normalized names.

tests/functional/test_new_resolver.py

@@ -1,10 +1,8 @@
-import json
 import os
 import sys
 import textwrap
 
 import pytest
-from pip._vendor.packaging.utils import canonicalize_name
 
 from tests.lib import (
     create_basic_sdist_for_package,
@@ -17,26 +15,14 @@ from tests.lib.path import Path
 from tests.lib.wheel import make_wheel
 
 
+# TODO: Remove me.
 def assert_installed(script, **kwargs):
-    ret = script.pip('list', '--format=json')
-    installed = {
-        (canonicalize_name(val['name']), val['version'])
-        for val in json.loads(ret.stdout)
-    }
-    expected = {(canonicalize_name(k), v) for k, v in kwargs.items()}
-    assert expected <= installed, f"{expected!r} not all in {installed!r}"
+    script.assert_installed(**kwargs)
 
 
+# TODO: Remove me.
 def assert_not_installed(script, *args):
-    ret = script.pip("list", "--format=json")
-    installed = {
-        canonicalize_name(val["name"])
-        for val in json.loads(ret.stdout)
-    }
-    # None of the given names should be listed as installed, i.e. their
-    # intersection should be empty.
-    expected = {canonicalize_name(k) for k in args}
-    assert not (expected & installed), f"{expected!r} contained in {installed!r}"
+    script.assert_not_installed(*args)
 
 
 def assert_editable(script, *args):

tests/functional/test_new_resolver_hashes.py

@@ -1,9 +1,7 @@
 import collections
 import hashlib
-import json
 
 import pytest
-from pip._vendor.packaging.utils import canonicalize_name
 
 from pip._internal.utils.urls import path_to_url
 from tests.lib import create_basic_sdist_for_package, create_basic_wheel_for_package
@@ -13,30 +11,6 @@ _FindLinks = collections.namedtuple(
 )
 
 
-def assert_installed(script, **kwargs):
-    ret = script.pip('list', '--format=json')
-    installed = set(
-        (canonicalize_name(val['name']), val['version'])
-        for val in json.loads(ret.stdout)
-    )
-    expected = set((canonicalize_name(k), v) for k, v in kwargs.items())
-    assert expected <= installed, \
-        "{!r} not all in {!r}".format(expected, installed)
-
-
-def assert_not_installed(script, *args):
-    ret = script.pip("list", "--format=json")
-    installed = set(
-        canonicalize_name(val["name"])
-        for val in json.loads(ret.stdout)
-    )
-    # None of the given names should be listed as installed, i.e. their
-    # intersection should be empty.
-    expected = set(canonicalize_name(k) for k in args)
-    assert not (expected & installed), \
-        "{!r} contained in {!r}".format(expected, installed)
-
-
 def _create_find_links(script):
     sdist_path = create_basic_sdist_for_package(script, "base", "0.1.0")
     wheel_path = create_basic_wheel_for_package(script, "base", "0.1.0")
@@ -265,7 +239,7 @@ def test_new_resolver_hash_requirement_and_url_constraint_can_succeed(
         "--requirement", requirements_txt,
     )
 
-    assert_installed(script, base="0.1.0")
+    script.assert_installed(base="0.1.0")
 
 
 @pytest.mark.parametrize("constrain_by_hash", [False, True])
@@ -307,4 +281,4 @@ def test_new_resolver_hash_requirement_and_url_constraint_can_fail(
         "THESE PACKAGES DO NOT MATCH THE HASHES FROM THE REQUIREMENTS FILE."
     ) in result.stderr, str(result)
 
-    assert_not_installed(script, "base", "other")
+    script.assert_not_installed("base", "other")

tests/functional/test_uninstall.py

@@ -1,4 +1,3 @@
-import json
 import logging
 import os
 import sys
@@ -46,8 +45,7 @@ def test_basic_uninstall_distutils(script):
     """))
     result = script.run('python', pkg_path / 'setup.py', 'install')
     result = script.pip('list', '--format=json')
-    assert {"name": "distutils-install", "version": "0.1"} \
-        in json.loads(result.stdout)
+    script.assert_installed(distutils_install="0.1")
     result = script.pip('uninstall', 'distutils_install', '-y',
                         expect_stderr=True, expect_error=True)
     assert (
@@ -217,16 +215,13 @@ def test_uninstall_entry_point_colon_in_name(script, console_scripts):
     )
     if sys.platform == 'win32':
         script_name += '.exe'
-    result = script.pip('install', pkg_path)
+    script.pip('install', pkg_path)
     assert script_name.exists()
-    result = script.pip('list', '--format=json')
-    assert {"name": "ep-install", "version": "0.1"} \
-        in json.loads(result.stdout)
+    script.assert_installed(ep_install="0.1")
+
     script.pip('uninstall', 'ep_install', '-y')
     assert not script_name.exists()
-    result2 = script.pip('list', '--format=json')
-    assert {"name": "ep-install", "version": "0.1"} \
-        not in json.loads(result2.stdout)
+    script.assert_not_installed("ep-install")
 
 
 def test_uninstall_gui_scripts(script):
@@ -550,9 +545,7 @@ def test_uninstall_setuptools_develop_install(script, data):
                expect_stderr=True, cwd=pkg_path)
     script.run('python', 'setup.py', 'install',
                expect_stderr=True, cwd=pkg_path)
-    list_result = script.pip('list', '--format=json')
-    assert {"name": os.path.normcase("FSPkg"), "version": "0.1.dev0"} \
-        in json.loads(list_result.stdout), str(list_result)
+    script.assert_installed(FSPkg="0.1.dev0")
     # Uninstall both develop and install
     uninstall = script.pip('uninstall', 'FSPkg', '-y')
     assert any(filename.endswith('.egg')
@@ -561,8 +554,7 @@ def test_uninstall_setuptools_develop_install(script, data):
     assert join(
         script.site_packages, 'FSPkg.egg-link'
     ) in uninstall2.files_deleted, list(uninstall2.files_deleted.keys())
-    list_result2 = script.pip('list', '--format=json')
-    assert "FSPkg" not in {p["name"] for p in json.loads(list_result2.stdout)}
+    script.assert_not_installed("FSPkg")
 
 
 def test_uninstall_editable_and_pip_install(script, data):
@@ -578,9 +570,7 @@ def test_uninstall_editable_and_pip_install(script, data):
     # ensure both are installed with --ignore-installed:
     script.pip('install', '--ignore-installed', '.',
                expect_stderr=True, cwd=pkg_path)
-    list_result = script.pip('list', '--format=json')
-    assert {"name": "FSPkg", "version": "0.1.dev0"} \
-        in json.loads(list_result.stdout)
+    script.assert_installed(FSPkg="0.1.dev0")
     # Uninstall both develop and install
     uninstall = script.pip('uninstall', 'FSPkg', '-y')
     assert not any(filename.endswith('.egg-link')
@@ -589,8 +579,7 @@ def test_uninstall_editable_and_pip_install(script, data):
     assert join(
         script.site_packages, 'FSPkg.egg-link'
     ) in uninstall2.files_deleted, list(uninstall2.files_deleted.keys())
-    list_result2 = script.pip('list', '--format=json')
-    assert "FSPkg" not in {p["name"] for p in json.loads(list_result2.stdout)}
+    script.assert_not_installed("FSPkg")
 
 
 def test_uninstall_editable_and_pip_install_easy_install_remove(script, data):
@@ -616,9 +605,7 @@ def test_uninstall_editable_and_pip_install_easy_install_remove(script, data):
     os.rename(easy_install_pth, pip_test_fspkg_pth)
 
     # Confirm that FSPkg is installed
-    list_result = script.pip('list', '--format=json')
-    assert {"name": "FSPkg", "version": "0.1.dev0"} \
-        in json.loads(list_result.stdout)
+    script.assert_installed(FSPkg="0.1.dev0")
 
     # Remove pip-test-fspkg.pth
     os.remove(pip_test_fspkg_pth)
@@ -632,9 +619,7 @@ def test_uninstall_editable_and_pip_install_easy_install_remove(script, data):
     ) in uninstall.files_deleted, list(uninstall.files_deleted.keys())
 
     # Confirm that FSPkg is uninstalled
-    list_result = script.pip('list', '--format=json')
-    assert {"name": "FSPkg", "version": "0.1.dev0"} \
-        not in json.loads(list_result.stdout)
+    script.assert_not_installed("FSPkg")
 
     # Rename pip-test.pth back to easy-install.pth
     os.rename(pip_test_pth, easy_install_pth)

tests/lib/__init__.py

@@ -1,3 +1,4 @@
+import json
 import os
 import re
 import shutil
@@ -14,6 +15,7 @@ from typing import List, Optional
 from zipfile import ZipFile
 
 import pytest
+from pip._vendor.packaging.utils import canonicalize_name
 from scripttest import FoundDir, TestFileEnvironment
 
 from pip._internal.index.collector import LinkCollector
@@ -668,6 +670,27 @@ class PipTestEnvironment(TestFileEnvironment):
         args = ("-m", "easy_install") + args
         return self.run("python", *args, **kwargs)
 
+    def assert_installed(self, **kwargs):
+        ret = self.pip("list", "--format=json")
+        installed = set(
+            (canonicalize_name(val["name"]), val["version"])
+            for val in json.loads(ret.stdout)
+        )
+        expected = set((canonicalize_name(k), v) for k, v in kwargs.items())
+        assert expected <= installed, "{!r} not all in {!r}".format(expected, installed)
+
+    def assert_not_installed(self, *args):
+        ret = self.pip("list", "--format=json")
+        installed = set(
+            canonicalize_name(val["name"]) for val in json.loads(ret.stdout)
+        )
+        # None of the given names should be listed as installed, i.e. their
+        # intersection should be empty.
+        expected = set(canonicalize_name(k) for k in args)
+        assert not (expected & installed), "{!r} contained in {!r}".format(
+            expected, installed
+        )
+
 
 # FIXME ScriptTest does something similar, but only within a single
 # ProcResult; this generalizes it so states can be compared across