MAINT: use the scientific python extra pip index for dev wheels

Keep reinstalling numpy with a separated pip command to ensure the dev version is picked up even if a downstream dependency upper limited it

Author: bsipocz

tox.ini

@@ -8,6 +8,9 @@ requires =
 
 description = run tests
 
+setenv =
+    devdeps: PIP_EXTRA_INDEX_URL =  https://pypi.anaconda.org/scientific-python-nightly-wheels/simple
+
 deps =
     # We use these files to specify all the dependencies, and below we override
     # versions for specific testing schenarios
@@ -20,13 +23,16 @@ deps =
     oldestdeps: scipy==1.8
     oldestdeps: pandas==1.4
 
+    devdeps: numpy>=0.0.dev0
+    devdeps: scipy>=0.0.dev0
+    devdeps: matplotlib>=0.0.dev0
+    devdeps: pandas>=0.0.dev0
+
 allowlist_externals = bash
 
 commands =
-    devdeps: pip install -U --pre --only-binary :all: -i https://pypi.anaconda.org/scipy-wheels-nightly/simple numpy
-    devdeps: pip install -U --pre --only-binary :all: -i https://pypi.anaconda.org/scipy-wheels-nightly/simple scipy
-    devdeps: pip install -U --pre --only-binary :all: -i https://pypi.anaconda.org/scipy-wheels-nightly/simple matplotlib
-    devdeps: pip install -U --pre --only-binary :all: -i https://pypi.anaconda.org/scipy-wheels-nightly/simple pandas
+    # Force numpy reinstall to work around upper version limits in downstream dependencies (e.g. pandas)
+    devdeps: pip install -U --pre --no-deps --extra-index-url https://pypi.anaconda.org/scientific-python-nightly-wheels/simple numpy
 
     pip freeze