Merge pull request #29 from DavidCEllis/fix_union_annotations

Fix an issue with union annotations in Python 3.14

.github/workflows/auto_test.yml

@@ -14,7 +14,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest]
-        python-version: ["3.13-dev", "3.12", "3.11", "3.10", "pypy-3.10", "3.9", "3.8"]
+        python-version: ["3.13", "3.12", "3.11", "3.10", "pypy-3.10", "3.9", "3.8"]
 
     steps:
     - uses: actions/checkout@v4
@@ -42,7 +42,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          python -m pip install -e .[testing]
+          python -m pip install -e .[testing,type_checking]
       - name: Check type stub files
         run: |
           python -m mypy.stubtest ducktools.classbuilder

pyproject.toml

@@ -27,19 +27,19 @@ classifiers = [
 dynamic = ['version']
 license = {file = "LICENSE.md"}
 
+[project.optional-dependencies]
+testing = ["pytest>=8.2", "pytest-cov", "typing_extensions"]
+type_checking = ["mypy"]
+performance_tests = ["attrs", "pydantic"]
+docs = ["sphinx", "myst-parser", "sphinx_rtd_theme"]
+
 [tool.setuptools.packages.find]
 where = ["src"]
 
 [tool.setuptools_scm]
 version_file = "src/ducktools/classbuilder/_version.py"
 version_file_template = "__version__ = \"{version}\"\n__version_tuple__ = {version_tuple}\n"
 
-
-[project.optional-dependencies]
-testing = ["pytest>=8.2", "pytest-cov", "mypy", "typing_extensions"]
-performance_tests = ["attrs", "pydantic"]
-docs = ["sphinx", "myst-parser", "sphinx_rtd_theme"]
-
 [project.urls]
 "Homepage" = "https://github.com/davidcellis/ducktools-classbuilder"
 

src/ducktools/classbuilder/annotations.py

@@ -37,6 +37,36 @@ def f():
 # End evil stuff from types.py
 
 
+class _Stringlike(str):
+    # There are typing operators that are not supported by strings
+    # This adds the 'or' operator '|'
+
+    def __or__(self, other):
+        if isinstance(other, str):
+            other_r = other
+        elif name := getattr(other, "__name__", None):
+            other_r = name
+        else:
+            other_r = str(other)
+
+        return type(self)(f"{self} | {other_r}")
+
+    def __ror__(self, other):
+        if isinstance(other, str):
+            other_r = other
+        elif name := getattr(other, "__name__", None):
+            other_r = name
+        else:
+            other_r = str(other)
+
+        return type(self)(f"{other_r} | {self}")
+
+    def __repr__(self):
+        base = super().__repr__()
+        clsname = type(self).__name__
+        return f"{clsname}({base})"
+
+
 class _StringGlobs(dict):
     """
     Based on the fake globals dictionary used for annotations
@@ -47,7 +77,7 @@ class _StringGlobs(dict):
     is not found.
     """
     def __missing__(self, key):
-        return key
+        return _Stringlike(key)
 
     def __repr__(self):
         cls_name = self.__class__.__name__
@@ -165,7 +195,14 @@ def call_annotate_func(annotate):
         closure = None
 
     new_annotate = _FunctionType(annotate.__code__, globs, closure=closure)
-    return new_annotate(1)
+
+    # Convert _Stringlike back to str
+    annos = {
+        k: str(v) if isinstance(v, _Stringlike) else v
+        for k, v in new_annotate(1).items()
+    }
+
+    return annos
 
 
 def get_ns_annotations(ns, eval_str=True):