Merge pull request #13039 from janlazo/vim-8.2.1790

vim-patch:8.1.{1812,2024,2239,2242,2247,2249,2253},8.2.{354,603,609,665,1570,1790,1792,1801}

src/nvim/testdir/check.vim

@@ -25,6 +25,14 @@ func CheckFunction(name)
   endif
 endfunc
 
+" Command to check for the presence of python.  Argument should have been
+" obtained with PythonProg()
+func CheckPython(name)
+  if a:name == ''
+    throw 'Skipped: python command not available'
+  endif
+endfunc
+
 " Command to check for running on MS-Windows
 command CheckMSWindows call CheckMSWindows()
 func CheckMSWindows()