switch to separate cmd script

appveyor.yml

@@ -46,16 +46,4 @@ build: off
 
 # to run your custom scripts instead of automatic tests
 test_script:
-  - cmd: >-
-      jlpm
-      If "%PYTHON_VERSION%"=="3.6" ( 
-        py.test
-        python -m jupyterlab.selenium_check
-        python -m jupyterlab.selenium_check --dev-mode
-      ) Else (
-        jlpm run integrity
-        jlpm run build
-        jlpm run build:test
-        (jlpm test) -OR (jlpm test) -OR (jlpm test)
-        jupyter lab build
-      )
+  - "cmd /E:ON /V:ON /C .\\scripts\\appveyor.cmd"

scripts/appveyor.cmd

@@ -0,0 +1,14 @@
+
+jlpm
+
+IF "%PYTHON_VERSION%"=="3.6" ( 
+    py.test
+    python -m jupyterlab.selenium_check
+    python -m jupyterlab.selenium_check --dev-mode
+) ELSE (
+    jlpm run integrity
+    jlpm run build
+    jlpm run build:test
+    jlpm test || jlpm test || jlpm test
+    jupyter lab build
+)