fix tabpage errors

tests/tabpage.test.vim

@@ -0,0 +1,59 @@
+source lib/shared.vim
+
+function! SetUp()
+  if exists ( 'g:loaded_vimpector' )
+    unlet g:loaded_vimpector
+  endif
+
+  let g:vimspector_enable_mappings = 'HUMAN'
+  source vimrc
+
+  " This is a bit of a hack
+  runtime! plugin/**/*.vim
+endfunction
+
+function! Test_Step_With_Different_Tabpage()
+  lcd testdata/cpp/simple
+  edit simple.cpp
+
+  " Add the breakpoing
+  " TODO refactor FeedKeys
+  15
+  call assert_equal( 15, line( '.' ) )
+  call feedkeys( "\<F9>", 'xt' )
+
+  " Here we go. Start Debugging
+  call feedkeys( "\<F5>", 'xt' )
+
+  call assert_equal( 2, len( gettabinfo() ) )
+  let vimspector_tabnr = tabpagenr()
+  call WaitForAssert( {->
+        \ assert_equal( 'simple.cpp', bufname( '%' ), 'Current buffer' )
+        \ }, 10000 )
+  call assert_equal( 15, line( '.' ), 'Current line' )
+  call assert_equal( 1, col( '.' ), 'Current column' )
+
+  " Switch to the other tab
+  normal gt
+
+  call assert_notequal( vimspector_tabnr, tabpagenr() )
+
+  " trigger some output by hacking into the vimspector python
+  call py3eval( '_vimspector_session._outputView.Print( "server",'
+            \ . '                                       "This is a test" )' )
+
+  " Step - jumps back to our vimspector tab
+  call feedkeys( "\<F10>", 'xt' )
+
+  call WaitForAssert( {-> assert_equal( vimspector_tabnr, tabpagenr() ) } )
+  call WaitForAssert( {-> assert_equal( 16, line( '.' ), 'Current line' ) } )
+  call assert_equal( 'simple.cpp', bufname( '%' ), 'Current buffer' )
+  call assert_equal( 1, col( '.' ), 'Current column' )
+
+  call vimspector#Reset()
+  call vimspector#ClearBreakpoints()
+
+  lcd -
+  %bwipeout!
+endfunction
+