Try to clean things up using ps instead of cmd

appveyor.yml

@@ -2,7 +2,7 @@ version: 1.0.{build}
 
 skip_branch_with_pr: true
 
-os: 
+os:
   - Visual Studio 2015
   - Visual Studio 2017
 
@@ -11,31 +11,25 @@ platform:
 
 before_build:
 - del "C:\Program Files (x86)\MSBuild\14.0\Microsoft.Common.targets\ImportAfter\Xamarin.Common.targets"
-- if not exist C:\projects\adios2build\NUL echo 'Build tree does not yet exist'
-- set CUSTOM_BUILD_NAME=%APPVEYOR_PULL_REQUEST_HEAD_REPO_BRANCH%_%APPVEYOR_BUILD_NUMBER%_%APPVEYOR_BUILD_WORKER_IMAGE%
-- ctest.exe
-  -VV -S ../adios2/scripts\appveyor\av_default.cmake
-  -Ddashboard_full=OFF
-  -Ddashboard_do_update=true
-  -DCTEST_BUILD_NAME=%CUSTOM_BUILD_NAME%
+- ps: Write-Host "$env:APPVEYOR_BUILD_WORKER_IMAGE"
+- ps: $env:CUSTOM_BUILD_NAME = ("{0}_{1}_{2}" -f $env:APPVEYOR_PULL_REQUEST_HEAD_REPO_BRANCH, $env:APPVEYOR_BUILD_NUMBER, $env:APPVEYOR_BUILD_WORKER_IMAGE -replace " ","-" )
+- ctest.exe -VV -S ../adios2/scripts\appveyor\av_default.cmake
+    -Ddashboard_full=OFF
+    -Ddashboard_do_update=true
+    -DCTEST_BUILD_NAME=%CUSTOM_BUILD_NAME%
 
 build_script:
-- set CUSTOM_BUILD_NAME=%APPVEYOR_PULL_REQUEST_HEAD_REPO_BRANCH%_%APPVEYOR_BUILD_NUMBER%_%APPVEYOR_BUILD_WORKER_IMAGE%
-- ctest.exe
-  -VV -S ../adios2/scripts\appveyor\av_default.cmake
-  -Ddashboard_full=OFF
-  -Ddashboard_do_configure=true
-  -DCTEST_BUILD_NAME=%CUSTOM_BUILD_NAME%
-- ctest.exe
-  -VV -S ../adios2/scripts\appveyor\av_default.cmake
-  -Ddashboard_full=OFF
-  -Ddashboard_do_build=true
-  -DCTEST_BUILD_NAME=%CUSTOM_BUILD_NAME%
+- ctest.exe -VV -S ../adios2/scripts\appveyor\av_default.cmake
+    -Ddashboard_full=OFF
+    -Ddashboard_do_configure=true
+    -DCTEST_BUILD_NAME=%CUSTOM_BUILD_NAME%
+- ctest.exe -VV -S ../adios2/scripts\appveyor\av_default.cmake
+    -Ddashboard_full=OFF
+    -Ddashboard_do_build=true
+    -DCTEST_BUILD_NAME=%CUSTOM_BUILD_NAME%
 
 test_script:
-- set CUSTOM_BUILD_NAME=%APPVEYOR_PULL_REQUEST_HEAD_REPO_BRANCH%_%APPVEYOR_BUILD_NUMBER%_%APPVEYOR_BUILD_WORKER_IMAGE%
-- ctest.exe
-  -VV -S ../adios2/scripts\appveyor\av_default.cmake
-  -Ddashboard_full=OFF
-  -Ddashboard_do_test=true
-  -DCTEST_BUILD_NAME=%CUSTOM_BUILD_NAME%
+- ctest.exe -VV -S ../adios2/scripts\appveyor\av_default.cmake
+    -Ddashboard_full=OFF
+    -Ddashboard_do_test=true
+    -DCTEST_BUILD_NAME=%CUSTOM_BUILD_NAME%