Add type checks and typing

.github/workflows/linters.yml

@@ -50,3 +50,21 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-python@v2
       - uses: psf/black@stable
+
+  mypy:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up Python 3.8
+        uses: actions/setup-python@v2
+        with:
+          python-version: 3.8
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -r requirements-lint.txt
+      - name: Run pydocstyle
+        run: |
+          mypy src/ tests/

.gitignore

@@ -7,3 +7,6 @@ __pycache__
 # coverage
 .coverage
 coverage.xml
+
+#typing
+.pytype

mypy.ini

@@ -0,0 +1,26 @@
+[mypy]
+check_untyped_defs = True
+show_error_codes = True
+mypy_path = src
+warn_unused_ignores = True
+warn_redundant_casts = True
+warn_unused_configs = True
+disallow_untyped_calls = True
+disallow_untyped_defs = True
+disallow_incomplete_defs = True
+no_implicit_optional = False
+
+[mypy-pytest.*]
+ignore_missing_imports = True
+
+[mypy-zope.*]
+ignore_missing_imports = True
+
+[mypy-sqlalchemy.*]
+ignore_missing_imports = True
+
+[mypy-pyramid.*]
+ignore_missing_imports = True
+
+[mypy-inflect.*]
+ignore_missing_imports = True

requirements-lint.txt

@@ -1,3 +1,4 @@
 black==20.8b1
 pydocstyle==5.1.1
 pycodestyle==2.6.0
+mypy==0.790

setup.cfg

@@ -65,3 +65,64 @@ ignore = D203,D212
 [pycodestyle]
 max-line-length = 120
 exclude = docs/*,build/*,venv/*
+# NOTE: All relative paths are relative to the location of this file.
+
+[pytype]
+
+# Space-separated list of files or directories to exclude.
+exclude =
+    **/*_test.py
+    **/test_*.py
+
+# Space-separated list of files or directories to process.
+inputs =
+    src/
+
+# Keep going past errors to analyze as many files as possible.
+keep_going = False
+
+# Run N jobs in parallel. When 'auto' is used, this will be equivalent to the
+# number of CPUs on the host system.
+jobs = 4
+
+# All pytype output goes here.
+output = .pytype
+
+# Paths to source code directories, separated by ':'.
+pythonpath =
+    .
+
+# Python version (major.minor) of the target code.
+python_version = 3.8
+
+# Check attribute values against their annotations. This flag is temporary and
+# will be removed once this behavior is enabled by default.
+check_attribute_types = False
+
+# Check container mutations against their annotations. This flag is temporary
+# and will be removed once this behavior is enabled by default.
+check_container_types = False
+
+# Check parameter defaults and assignments against their annotations. This flag
+# is temporary and will be removed once this behavior is enabled by default.
+check_parameter_types = False
+
+# Check variable values against their annotations. This flag is temporary and
+# will be removed once this behavior is enabled by default.
+check_variable_types = False
+
+# Comma or space separated list of error names to ignore.
+disable =
+    pyi-error
+
+# Don't report errors.
+report_errors = True
+
+# Experimental: Infer precise return types even for invalid function calls.
+precise_return = False
+
+# Experimental: solve unknown types to label with structural types.
+protocols = False
+
+# Experimental: Only load submodules that are explicitly imported.
+strict_import = False

src/pyramid_basemodel/__init__.py

@@ -30,6 +30,8 @@ class and ``bind_engine`` function.
     "bind_engine",
 ]
 
+from typing import Any, Type, Callable
+
 import inflect
 from datetime import datetime
 
@@ -52,17 +54,17 @@ class and ``bind_engine`` function.
 classImplements(Base, IDeclarativeBase)
 
 
-class classproperty(object):
+class classproperty:
     """A basic [class property](http://stackoverflow.com/a/3203659)."""
 
-    def __init__(self, getter):
+    def __init__(self, getter: Callable[..., Any]) -> None:
         self.getter = getter
 
-    def __get__(self, instance, owner):
+    def __get__(self, instance: "BaseMixin", owner: Type["BaseMixin"]) -> Any:
         return self.getter(owner)
 
 
-class BaseMixin(object):
+class BaseMixin:
     """
     Default Base Model Mixin.
 
@@ -85,7 +87,7 @@ class BaseMixin(object):
     query = Session.query_property()
 
     @classproperty
-    def class_name(cls):
+    def class_name(cls) -> str:
         """
         Determine class name based on the _class_name or the __tablename__.
 

src/pyramid_basemodel/util.py

@@ -5,44 +5,39 @@
 import os
 import logging
 from binascii import hexlify
+from typing import Callable, Union, Any, Optional
 
-from sqlalchemy import schema
+from sqlalchemy import schema, Column
+from sqlalchemy.orm import Query
 
 logger = logging.getLogger(__name__)
 
 
-def generate_random_digest(num_bytes=28, urandom=None, to_hex=None):
+UrandFuncT = Callable[[int], bytes]
+HexlifyFuncT = Callable[..., bytes]
+
+def generate_random_digest(num_bytes: int=28, urandom: UrandFuncT=os.urandom, to_hex: HexlifyFuncT=hexlify) -> str:
     """
     Generate a random hash and returns the hex digest as a unicode string.
 
     :param num_bytes: number of bytes to random(select)
     :param urandom: urandom function
     :param to_hex: hexifying function
     """
-    # Compose.
-    if urandom is None:
-        urandom = os.urandom
-    if to_hex is None:
-        to_hex = hexlify
-
     # Get random bytes.
     r = urandom(num_bytes)
 
-    # Return as a unicode string.
+    # Return as a string.
     return to_hex(r).decode("utf-8")
 
 
-def ensure_unique(self, query, property_, value, max_iter=30, gen_digest=None):
+def ensure_unique(self, query: Query, property_: Column, value: str, max_iter: int=30, gen_digest=generate_random_digest) -> str:
     """
     Make sure slug is unique.
 
     Takes a ``candidate`` value for a unique ``property_`` and iterates,
     appending an incremented integer until unique.
     """
-    # Compose.
-    if gen_digest is None:
-        gen_digest = generate_random_digest
-
     # Unpack
     candidate = value
 
@@ -58,7 +53,7 @@ def ensure_unique(self, query, property_, value, max_iter=30, gen_digest=None):
             if instance != self:
                 existing = instance
                 break
-        if existing and n < 30:
+        if existing and n < max_iter:
             n += 1
             # If we've tried 1, 2 ... all the way to ``max_iter``, then
             # fallback on appending a random digest rather than a sequential