Use Pyright in CI

.devcontainer/devcontainer.json

@@ -10,6 +10,8 @@
   },
   // Set *default* container specific settings.json values on container create.
   "settings": {
+    // Enable pylance's pyright integration (disabled by default):
+    "python.analysis.typeCheckingMode": "basic",
     "python.defaultInterpreterPath": "/usr/local/bin/python",
     "python.linting.enabled": true,
     "python.linting.mypyEnabled": true,

.pre-commit-config.yaml

@@ -41,6 +41,12 @@ repos:
         language: system
         types: [python]
         exclude: setup.py|run_tests.py|docs/conf.py
+      - id: pyright
+        name: pyright
+        entry: pyright
+        language: node
+        types: [python]
+        exclude: setup.py|run_tests.py|docs/conf.py
 
   - repo: https://github.com/Lucas-C/pre-commit-hooks
     rev: v1.1.10

bidict/_base.py

@@ -184,7 +184,8 @@ def inverse(self) -> 'BidictBase[VT, KT]':
         self._invweak: 't.Optional[weakref.ReferenceType[BidictBase[VT, KT]]]' = None
         # Also store a weak reference back to `instance` on its inverse instance, so that
         # the second `.inverse` access in `bi.inverse.inverse` hits the cached weakref.
-        inv._inv, inv._invweak = None, weakref.ref(self)
+        inv._inv = None
+        inv._invweak = weakref.ref(self)
         # In e.g. `bidict().inverse.inverse`, this design ensures that a strong reference
         # back to the original instance is retained before its refcount drops to zero,
         # avoiding an unintended potential deallocation.
@@ -486,7 +487,7 @@ def _init_from(self, other: MapOrIterItems[KT, VT]) -> None:
         self._fwdm.update(other)
         # If other is a bidict, use its existing backing inverse mapping, otherwise
         # other could be a generator that's now exhausted, so invert self._fwdm on the fly.
-        inv = other.inverse if isinstance(other, BidictBase) else inverted(self._fwdm)
+        inv: MapOrIterItems[t.Any, t.Any] = other.inverse if isinstance(other, BidictBase) else inverted(self._fwdm)
         self._invm.update(inv)
 
     #: Used for the copy protocol.
@@ -496,15 +497,15 @@ def _init_from(self, other: MapOrIterItems[KT, VT]) -> None:
     def __or__(self: BT, other: t.Mapping[KT, VT]) -> BT:
         """Return self|other."""
         if not isinstance(other, t.Mapping):
-            return NotImplemented
+            return NotImplemented  # flagged by pyright
         new = self.copy()
         new._update(other, rbof=False)
         return new
 
     def __ror__(self: BT, other: t.Mapping[KT, VT]) -> BT:
         """Return other|self."""
         if not isinstance(other, t.Mapping):
-            return NotImplemented
+            return NotImplemented  # flagged by pyright
         new = self.__class__(other)
         new._update(self, rbof=False)
         return new

bidict/_bidict.py

@@ -110,7 +110,7 @@ def pop(self, __key: KT, __default: DT) -> t.Union[VT, DT]: ...
     @t.overload
     def pop(self, __key: KT) -> VT: ...
     @t.overload
-    def pop(self, __key: KT, __default: t.Union[VT, DT] = ...) -> t.Union[VT, DT]: ...
+    def pop(self, __key: KT, __default: t.Any = ...) -> t.Any: ...
 
     def pop(self, key: KT, default: ODT[DT] = MISSING) -> t.Union[VT, DT]:
         """*x.pop(k[, d]) → v*

bidict/_iter.py

@@ -9,13 +9,15 @@
 
 from collections.abc import Mapping
 from operator import itemgetter
+import typing as t
 
 from ._typing import KT, VT, IterItems, MapOrIterItems
 
 
 def iteritems_mapping_or_iterable(arg: MapOrIterItems[KT, VT]) -> IterItems[KT, VT]:
     """Yield the items in *arg* based on whether it's a mapping."""
-    yield from arg.items() if isinstance(arg, Mapping) else arg
+    it = iter(arg.items() if isinstance(arg, Mapping) else arg)
+    return t.cast(IterItems[KT, VT], it)
 
 
 def iteritems(__arg: MapOrIterItems[KT, VT], **kw: VT) -> IterItems[KT, VT]:

bidict/_orderedbase.py

@@ -58,7 +58,7 @@ class Node:
     __slots__ = ('_prv_weak', 'nxt', '__weakref__')
 
     def __init__(self, prv: 'Node', nxt: 'Node') -> None:
-        self.prv = prv
+        self.prv = prv  # flagged by pyright
         self.nxt = nxt
 
     def unlink(self) -> None:
@@ -98,7 +98,7 @@ def new_last_node(self) -> Node:
         """Create and return a new terminal node."""
         old_last = self.prv
         new_last = Node(old_last, self)
-        old_last.nxt = self.prv = new_last
+        old_last.nxt = self.prv = new_last  # flagged by pyright
         return new_last
 
 

bidict/_orderedbidict.py

@@ -55,9 +55,8 @@ def popitem(self, last: bool = True) -> t.Tuple[KT, VT]:
             raise KeyError('OrderedBidict is empty')
         node = getattr(self._sntl, 'prv' if last else 'nxt')
         korv = self._node_by_korv.inverse[node]
-        if self._bykey:
-            return korv, self._pop(korv)
-        return self.inverse._pop(korv), korv
+        kv = (korv, self._pop(korv)) if self._bykey else (self.inverse._pop(korv), korv)
+        return t.cast(t.Tuple[KT, VT], kv)
 
     def move_to_end(self, key: KT, last: bool = True) -> None:
         """Move the item with the given key to the end if *last* is true, else to the beginning.

pyrightconfig.json

@@ -0,0 +1,41 @@
+{
+  "exclude": [
+    "docs",
+    "tests",
+  ],
+  "reportConstantRedefinition": "error",
+  "reportDuplicateImport": "error",
+  "reportFunctionMemberAccess": "error",
+  "reportIncompatibleMethodOverride": "error",
+  "reportIncompatibleVariableOverride": "error",
+  "reportInvalidStringEscapeSequence": "error",
+  "reportInvalidStubStatement": "error",
+  "reportInvalidTypeVarUse": "error",
+  "reportMatchNotExhaustive": "error",
+  "reportMissingTypeArgument": "error",
+  "reportMissingTypeStubs": "error",
+  "reportOverlappingOverload": "error",
+  "reportPropertyTypeMismatch": "error",
+  "reportSelfClsParameterName": "error",
+  "reportUnknownLambdaType": "error",
+  "reportUnknownParameterType": "error",
+  "reportUnsupportedDunderAll": "error",
+  "reportUntypedBaseClass": "error",
+  "reportUntypedClassDecorator": "error",
+  "reportUntypedFunctionDecorator": "error",
+  "reportUntypedNamedTuple": "error",
+  "reportUnusedClass": "error",
+  "reportUnusedFunction": "error",
+  "reportUnusedImport": "error",
+  "reportUnusedVariable": "error",
+  "strictDictionaryInference": true,
+  "strictListInference": true,
+  "strictParameterNoneValue": true,
+
+  // Leave these off for now:
+  "reportPrivateUsage": "none",
+  "reportUnknownArgumentType": "none",
+  "reportUnknownMemberType": "none",
+  "reportUnknownVariableType": "none",
+  "reportUnusedCallResult": "none",
+}

requirements/dev.txt

@@ -67,7 +67,9 @@ markupsafe==2.1.0
 mccabe==0.6.1
     # via pylint
 nodeenv==1.6.0
-    # via pre-commit
+    # via
+    #   pre-commit
+    #   pyright
 packaging==21.3
     # via
     #   build
@@ -113,6 +115,8 @@ pylint==2.12.2
     # via -r lint.in
 pyparsing==3.0.7
     # via packaging
+pyright==1.1.228
+    # via -r lint.in
 pytest==7.0.1
     # via
     #   -r lint.in

requirements/lint.in

@@ -1,4 +1,5 @@
 pre-commit
+pyright
 pylint
 # pylint runs against tests/*.py which import pytest and hypothesis
 pytest

requirements/lint.txt

@@ -29,7 +29,9 @@ lazy-object-proxy==1.7.1
 mccabe==0.6.1
     # via pylint
 nodeenv==1.6.0
-    # via pre-commit
+    # via
+    #   pre-commit
+    #   pyright
 packaging==21.3
     # via pytest
 platformdirs==2.5.1
@@ -46,6 +48,8 @@ pylint==2.12.2
     # via -r lint.in
 pyparsing==3.0.7
     # via packaging
+pyright==1.1.228
+    # via -r lint.in
 pytest==7.0.1
     # via -r lint.in
 pyyaml==6.0