Fix appveyor tests

Author: isuruf

appveyor.yml

@@ -1,8 +1,6 @@
 version: '{build}'
 
-# Uncomment this to enable the fast build environment if your account does not
-# support it automatically:
-#os: Visual Studio 2015 RC
+image: Visual Studio 2019
 
 environment:
   global:
@@ -16,7 +14,6 @@ environment:
       CONDA_INSTALL_LOCN: C:\\Miniconda36-x64
       WITH_MPFR: yes
       WITH_MPC: yes
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
     - BUILD_TYPE: "Release"
       COMPILER: MSVC15
       PLATFORM: "x64"
@@ -45,7 +42,6 @@ environment:
       PLATFORM: "x64"
       PYTHON_VERSION: 310-x64
       CONDA_INSTALL_LOCN: C:\\Miniconda36-x64
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
       WITH_MPFR: yes
       WITH_MPC: yes
       WITH_LLVM: yes
@@ -103,15 +99,16 @@ install:
 - if [%COMPILER%]==[MinGW]  set "CMAKE_GENERATOR=MinGW Makefiles"
 - if [%COMPILER%]==[MinGW-w64] set "CMAKE_GENERATOR=MinGW Makefiles"
 
-- if [%COMPILER%]==[MSVC15] cmake -DCMAKE_PREFIX_PATH=%CONDA_PREFIX%\Library ..
-- if [%COMPILER%]==[MinGW] cmake -DCMAKE_PREFIX_PATH=C:\MinGW -DCMAKE_BUILD_TYPE=%BUILD_TYPE% ..
-- if [%COMPILER%]==[MinGW-w64] cmake -DCMAKE_PREFIX_PATH=C:\mingw64 -DCMAKE_BUILD_TYPE=%BUILD_TYPE% ..
+- if [%COMPILER%]==[MSVC15] set "CMAKE_ARGS=-DCMAKE_PREFIX_PATH=%CONDA_PREFIX%\\Library"
+- if [%COMPILER%]==[MinGW] set "CMAKE_ARGS=-DCMAKE_PREFIX_PATH=C:\MinGW -DCMAKE_BUILD_TYPE=%BUILD_TYPE%"
+- if [%COMPILER%]==[MinGW-w64] set "CMAKE_ARGS=-DCMAKE_PREFIX_PATH=C:\mingw64 -DCMAKE_BUILD_TYPE=%BUILD_TYPE%"
 
-- if [%WITH_MPFR%]==[yes] cmake -DWITH_MPFR=yes ..
-- if [%WITH_MPC%]==[yes] cmake -DWITH_MPC=yes ..
-- if [%WITH_LLVM%]==[yes] cmake -DWITH_LLVM=yes -DMSVC_USE_MT=no ..
+- if [%WITH_MPFR%]==[yes] set "CMAKE_ARGS=%CMAKE_ARGS% -DWITH_MPFR=yes"
+- if [%WITH_MPC%]==[yes] set "CMAKE_ARGS=%CMAKE_ARGS% -DWITH_MPC=yes"
+- if [%WITH_LLVM%]==[yes] set "CMAKE_ARGS=%CMAKE_ARGS% -DWITH_LLVM=yes -DMSVC_USE_MT=no"
 
-- cmake -DBUILD_SHARED_LIBS=yes -DBUILD_TESTS=no -DBUILD_BENCHMARKS=no -DCMAKE_INSTALL_PREFIX=C:\symengine ..
+- echo "CMAKE_ARGS: %CMAKE_ARGS%"
+- cmake %CMAKE_ARGS% -DBUILD_SHARED_LIBS=yes -DBUILD_TESTS=no -DBUILD_BENCHMARKS=no -DCMAKE_INSTALL_PREFIX=C:\symengine ..
 
 - cmake --build . --config %BUILD_TYPE% --target install
 - cd ../../