Modernize code to Python 3.6+ (#1158)

* Compact dict and set building
* Remove redundant parentheses
* Simplify chained conditions
* Change method name to lowercase
* Use triple double quotes for docstrings

Thanks, @eumiro!

tests/fixtures.py

@@ -751,7 +751,7 @@ def assert_permissions_checked(datasette, actions):
     help="Delete and recreate database if it exists",
 )
 def cli(db_filename, metadata, plugins_path, recreate):
-    "Write out the fixtures database used by Datasette's test suite"
+    """Write out the fixtures database used by Datasette's test suite"""
     if metadata and not metadata.endswith(".json"):
         raise click.ClickException("Metadata should end with .json")
     if not db_filename.endswith(".db"):

tests/plugins/my_plugin.py

@@ -12,7 +12,7 @@ ureg = pint.UnitRegistry()
 @hookimpl
 def prepare_connection(conn, database, datasette):
     def convert_units(amount, from_, to_):
-        "select convert_units(100, 'm', 'ft');"
+        """select convert_units(100, 'm', 'ft');"""
         return (amount * ureg(from_)).to(to_).to_tuple()[0]
 
     conn.create_function("convert_units", 3, convert_units)

tests/test_api.py

@@ -789,7 +789,7 @@ def test_table_shape_object(app_client):
     } == response.json
 
 
-def test_table_shape_object_compound_primary_Key(app_client):
+def test_table_shape_object_compound_primary_key(app_client):
     response = app_client.get("/fixtures/compound_primary_key.json?_shape=object")
     assert {"a,b": {"pk1": "a", "pk2": "b", "content": "c"}} == response.json
 
@@ -871,7 +871,7 @@ def test_validate_page_size(app_client, path, expected_error):
 
 
 def test_page_size_zero(app_client):
-    "For _size=0 we return the counts, empty rows and no continuation token"
+    """For _size=0 we return the counts, empty rows and no continuation token"""
     response = app_client.get("/fixtures/no_primary_key.json?_size=0")
     assert 200 == response.status
     assert [] == response.json["rows"]

tests/test_auth.py

@@ -5,7 +5,7 @@ import time
 
 
 def test_auth_token(app_client):
-    "The /-/auth-token endpoint sets the correct cookie"
+    """The /-/auth-token endpoint sets the correct cookie"""
     assert app_client.ds._root_token is not None
     path = f"/-/auth-token?token={app_client.ds._root_token}"
     response = app_client.get(
@@ -29,7 +29,7 @@ def test_auth_token(app_client):
 
 
 def test_actor_cookie(app_client):
-    "A valid actor cookie sets request.scope['actor']"
+    """A valid actor cookie sets request.scope['actor']"""
     cookie = app_client.actor_cookie({"id": "test"})
     response = app_client.get("/", cookies={"ds_actor": cookie})
     assert {"id": "test"} == app_client.ds._last_request.scope["actor"]

tests/test_cli.py

@@ -110,7 +110,7 @@ def test_plugins_cli(app_client):
     result2 = runner.invoke(cli, ["plugins", "--all"])
     names = [p["name"] for p in json.loads(result2.output)]
     # Should have all the EXPECTED_PLUGINS
-    assert set(names).issuperset(set(p["name"] for p in EXPECTED_PLUGINS))
+    assert set(names).issuperset({p["name"] for p in EXPECTED_PLUGINS})
     # And the following too:
     assert set(names).issuperset(DEFAULT_PLUGINS)
 

tests/test_docs.py

@@ -15,7 +15,7 @@ label_re = re.compile(r"\.\. _([^\s:]+):")
 
 def get_headings(content, underline="-"):
     heading_re = re.compile(r"(\w+)(\([^)]*\))?\n\{}+\n".format(underline))
-    return set(h[0] for h in heading_re.findall(content))
+    return {h[0] for h in heading_re.findall(content)}
 
 
 def get_labels(filename):
@@ -96,11 +96,11 @@ def documented_table_filters():
     json_api_rst = (docs_path / "json_api.rst").read_text()
     section = json_api_rst.split(".. _table_arguments:")[-1]
     # Lines starting with ``?column__exact= are docs for filters
-    return set(
+    return {
         line.split("__")[1].split("=")[0]
         for line in section.split("\n")
         if line.startswith("``?column__")
-    )
+    }
 
 
 @pytest.mark.parametrize("filter", [f.key for f in Filters._filters])

tests/test_permissions.py

@@ -437,7 +437,7 @@ def cascade_app_client():
     ],
 )
 def test_permissions_cascade(cascade_app_client, path, permissions, expected_status):
-    "Test that e.g. having view-table but NOT view-database lets you view table page, etc"
+    """Test that e.g. having view-table but NOT view-database lets you view table page, etc"""
     allow = {"id": "*"}
     deny = {}
     previous_metadata = cascade_app_client.ds._metadata

tests/test_plugins.py

@@ -28,7 +28,7 @@ at_memory_re = re.compile(r" at 0x\w+")
     "plugin_hook", [name for name in dir(pm.hook) if not name.startswith("_")]
 )
 def test_plugin_hooks_have_tests(plugin_hook):
-    "Every plugin hook should be referenced in this test module"
+    """Every plugin hook should be referenced in this test module"""
     tests_in_this_module = [t for t in globals().keys() if t.startswith("test_hook_")]
     ok = False
     for test in tests_in_this_module: