Add back PyPy builds

Author: astrofrog

pyproject.toml

@@ -27,9 +27,8 @@ limited-api = true
 install = ['--skip-subprojects']
 
 [tool.cibuildwheel]
-# Build only with Python 3.10 to get cp310-abi3 wheels that work on all 3.10+
-build = ["cp310-*"]
-skip = ["pp*"]
+# Build cp310 for abi3 wheels (works on all CPython 3.10+) and PyPy
+build = ["cp310-*", "pp310-*"]
 
 [tool.cibuildwheel.linux]
 archs = ["auto", "aarch64"]
@@ -39,12 +38,18 @@ CC = "gcc"
 
 [tool.cibuildwheel.macos]
 archs = ["x86_64", "arm64"]
+skip = ["pp*"]
 
 [[tool.cibuildwheel.overrides]]
 select = "*-musllinux*"
 before-all = "apk add clang"
 environment = {CC = "clang"}
 
+# PyPy doesn't support limited API, so disable it for PyPy builds
+[[tool.cibuildwheel.overrides]]
+select = "pp*"
+config-settings = {"setup-args" = "-Dpython.allow_limited_api=false"}
+
 [tool.isort]
 profile = "black"
 line_length = 100