DEP: Loosely pin Cython to 3.0 (#56993)

Author: rhshadrach

asv_bench/asv.conf.json

@@ -41,7 +41,7 @@
     // pip (with all the conda available packages installed first,
     // followed by the pip installed packages).
     "matrix": {
-        "Cython": ["3.0.5"],
+        "Cython": ["3.0"],
         "matplotlib": [],
         "sqlalchemy": [],
         "scipy": [],

environment.yml

@@ -8,7 +8,7 @@ dependencies:
 
   # build dependencies
   - versioneer[toml]
-  - cython=3.0.5
+  - cython~=3.0.5
   - meson[ninja]=1.2.1
   - meson-python=0.13.1
 

pyproject.toml

@@ -5,7 +5,7 @@ requires = [
     "meson-python==0.13.1",
     "meson==1.2.1",
     "wheel",
-    "Cython==3.0.5",  # Note: sync with setup.py, environment.yml and asv.conf.json
+    "Cython~=3.0.5",  # Note: sync with setup.py, environment.yml and asv.conf.json
     # Any NumPy version should be fine for compiling.  Users are unlikely
     # to get a NumPy<1.25 so the result will be compatible with all relevant
     # NumPy versions (if not it is presumably compatible with their version).

requirements-dev.txt

@@ -3,7 +3,7 @@
 
 pip
 versioneer[toml]
-cython==3.0.5
+cython~==3.0.5
 meson[ninja]==1.2.1
 meson-python==0.13.1
 pytest>=7.3.2

setup.py

@@ -37,7 +37,7 @@ def is_platform_mac():
 
 
 # note: sync with pyproject.toml, environment.yml and asv.conf.json
-min_cython_ver = "3.0.5"
+min_cython_ver = "3.0"
 
 try:
     from Cython import (