PR: Debug Python 3.8 wheel building

appveyor.yml

@@ -17,25 +17,6 @@ environment:
     APPVEYOR_RDP_PASSWORD: "dcca4c4863E30d56c2e0dda6327370b3#"
 
   matrix:
-    - PYTHON_VERSION: "3.8"
-      PYTHON_ARCH: "32"
-      ARCH: "x86"
-    - PYTHON_VERSION: "3.7"
-      PYTHON_ARCH: "32"
-      ARCH: "x86"
-      platform: "x86"
-    - PYTHON_VERSION: "3.6"
-      PYTHON_ARCH: "32"
-      ARCH: "x86"
-      platform: "x86"
-    - PYTHON_VERSION: "3.5"
-      PYTHON_ARCH: "32"
-      ARCH: "x86"
-      platform: "x86"
-    - PYTHON_VERSION: "2.7"
-      PYTHON_ARCH: "32"
-      ARCH: "x86"
-      platform: "x86"
     - PYTHON_VERSION: "3.8"
       PYTHON_ARCH: "64"
       ARCH: "amd64"
@@ -56,6 +37,22 @@ environment:
       PYTHON_ARCH: "64"
       ARCH: "amd64"
       platform: "x64"
+    - PYTHON_VERSION: "3.7"
+      PYTHON_ARCH: "32"
+      ARCH: "x86"
+      platform: "x86"
+    - PYTHON_VERSION: "3.6"
+      PYTHON_ARCH: "32"
+      ARCH: "x86"
+      platform: "x86"
+    - PYTHON_VERSION: "3.5"
+      PYTHON_ARCH: "32"
+      ARCH: "x86"
+      platform: "x86"
+    - PYTHON_VERSION: "2.7"
+      PYTHON_ARCH: "32"
+      ARCH: "x86"
+      platform: "x86"
 
 install:
   # Astropy ci-helpers. See https://github.com/astropy/ci-helpers
@@ -68,8 +65,8 @@ install:
   # - "conda activate base"
   - "conda activate test"
   # - CALL "C:\\Program Files (x86)\\Microsoft Visual Studio 14.0\\VC\\vcvarsall.bat" %ARCH%
-  - "conda install -q --file requirements.txt"
-  - "pip install -q twine codecov"
+  # - "conda install -q --file conda.txt"
+  - "%CMD_IN_ENV% powershell appveyor/install.ps1"
   - "%CMD_IN_ENV% powershell appveyor/build.ps1"
 
 # Not a .NET project, we build in the install step instead
@@ -86,4 +83,4 @@ on_success:
   - "%CMD_IN_ENV% powershell appveyor/publish.ps1"
 
 # on_finish:
-  # - ps: $blockRdp = $true; iex ((new-object net.webclient).DownloadString('https://raw.githubusercontent.com/appveyor/ci/master/scripts/enable-rdp.ps1'))
+#   - ps: $blockRdp = $true; iex ((new-object net.webclient).DownloadString('https://raw.githubusercontent.com/appveyor/ci/master/scripts/enable-rdp.ps1'))

appveyor/install.ps1

@@ -0,0 +1,11 @@
+
+# Install general depedendencies for all Python versions
+conda install -q --file conda.txt
+
+# Install distribution and coverage tools
+pip install -q twine codecov coveralls pytest-cov
+
+if($env:PYTHON_VERSION -match "2.7") {
+    # On Python 2, we need to install this dependency
+    conda install -q backports.shutil_which
+}

requirements.txt → conda.txt

@@ -1,14 +1,10 @@
 # Build requirements
 cython
-python
 setuptools
 winpty
-backports.shutil_which
 m2w64-toolchain
 libpython
 
 # Test requirements
-pytest<5
-coveralls
+pytest
 flaky
-pytest-cov