vim-patch:8.2.1106: crash when trying to use s: variable in typed command

Problem:    Crash when trying to use s: variable in typed command.
Solution:   Don't use the script index when not set. (Ken Takata,
            closes vim/vim#6366)

https://github.com/vim/vim/commit/8e6cbb72324b6fb25d1a9abd6cc4d102d0e5f14e

3 files changed, 106 insertions, 75 deletions

diff --git a/src/nvim/testdir/test_vimscript.vim b/src/nvim/testdir/test_vimscript.vim
index 3a6baaf1f0..a7ab78d87a 100644
--- a/src/nvim/testdir/test_vimscript.vim
+++ b/src/nvim/testdir/test_vimscript.vim
@@ -1810,6 +1810,7 @@ func Test_float_conversion_errors()
   endif
 endfunc
 
+" invalid function names               {{{1
 func Test_invalid_function_names()
   " function name not starting with capital
   let caught_e128 = 0
@@ -1870,7 +1871,7 @@ func Test_invalid_function_names()
   call delete('Xscript')
 endfunc
 
-" substring and variable name
+" substring and variable name              {{{1
 func Test_substring_var()
   let str = 'abcdef'
   let n = 3
@@ -1890,6 +1891,20 @@ func Test_substring_var()
   unlet b:nn
 endfunc
 
+" Test using s: with a typed command              {{{1
+func Test_typed_script_var()
+  CheckRunVimInTerminal
+
+  let buf = RunVimInTerminal('', {'rows': 6})
+
+  " Deep nesting of if ... endif
+  call term_sendkeys(buf, ":echo get(s:, 'foo', 'x')\n")
+  call TermWait(buf)
+  call WaitForAssert({-> assert_match('^E116:', term_getline(buf, 5))})
+
+  call StopVimInTerminal(buf)
+endfunc
+
 func Test_for_over_string()
   let res = ''
   for c in 'aéc̀d'
diff --git a/test/functional/legacy/vimscript_spec.lua b/test/functional/legacy/vimscript_spec.lua
new file mode 100644
index 0000000000..f59a87f824
--- /dev/null
+++ b/test/functional/legacy/vimscript_spec.lua
@@ -0,0 +1,90 @@
+local helpers = require('test.functional.helpers')(after_each)
+local Screen = require('test.functional.ui.screen')
+local clear = helpers.clear
+local exec = helpers.exec
+local feed = helpers.feed
+local meths = helpers.meths
+
+before_each(clear)
+
+describe('Vim script', function()
+  -- oldtest: Test_deep_nest()
+  it('Error when if/for/while/try/function is nested too deep',function()
+    local screen = Screen.new(80, 24)
+    screen:attach()
+    meths.set_option('laststatus', 2)
+    exec([[
+      " Deep nesting of if ... endif
+      func Test1()
+        let @a = join(repeat(['if v:true'], 51), "\n")
+        let @a ..= "\n"
+        let @a ..= join(repeat(['endif'], 51), "\n")
+        @a
+        let @a = ''
+      endfunc
+
+      " Deep nesting of for ... endfor
+      func Test2()
+        let @a = join(repeat(['for i in [1]'], 51), "\n")
+        let @a ..= "\n"
+        let @a ..= join(repeat(['endfor'], 51), "\n")
+        @a
+        let @a = ''
+      endfunc
+
+      " Deep nesting of while ... endwhile
+      func Test3()
+        let @a = join(repeat(['while v:true'], 51), "\n")
+        let @a ..= "\n"
+        let @a ..= join(repeat(['endwhile'], 51), "\n")
+        @a
+        let @a = ''
+      endfunc
+
+      " Deep nesting of try ... endtry
+      func Test4()
+        let @a = join(repeat(['try'], 51), "\n")
+        let @a ..= "\necho v:true\n"
+        let @a ..= join(repeat(['endtry'], 51), "\n")
+        @a
+        let @a = ''
+      endfunc
+
+      " Deep nesting of function ... endfunction
+      func Test5()
+        let @a = join(repeat(['function X()'], 51), "\n")
+        let @a ..= "\necho v:true\n"
+        let @a ..= join(repeat(['endfunction'], 51), "\n")
+        @a
+        let @a = ''
+      endfunc
+    ]])
+    screen:expect({any = '%[No Name%]'})
+    feed(':call Test1()<CR>')
+    screen:expect({any = 'E579: '})
+    feed('<C-C>')
+    screen:expect({any = '%[No Name%]'})
+    feed(':call Test2()<CR>')
+    screen:expect({any = 'E585: '})
+    feed('<C-C>')
+    screen:expect({any = '%[No Name%]'})
+    feed(':call Test3()<CR>')
+    screen:expect({any = 'E585: '})
+    feed('<C-C>')
+    screen:expect({any = '%[No Name%]'})
+    feed(':call Test4()<CR>')
+    screen:expect({any = 'E601: '})
+    feed('<C-C>')
+    screen:expect({any = '%[No Name%]'})
+    feed(':call Test5()<CR>')
+    screen:expect({any = 'E1058: '})
+  end)
+
+  -- oldtest: Test_typed_script_var()
+  it('using s: with a typed command', function()
+    local screen = Screen.new(80, 24)
+    screen:attach()
+    feed(":echo get(s:, 'foo', 'x')\n")
+    screen:expect({any = 'E116: '})
+  end)
+end)
diff --git a/test/functional/vimscript/eval_spec.lua b/test/functional/vimscript/eval_spec.lua
index 64a3cf5471..9b0ace0882 100644
--- a/test/functional/vimscript/eval_spec.lua
+++ b/test/functional/vimscript/eval_spec.lua
@@ -16,7 +16,6 @@ local lfs = require('lfs')
 local clear = helpers.clear
 local eq = helpers.eq
 local exc_exec = helpers.exc_exec
-local exec = helpers.exec
 local exec_lua = helpers.exec_lua
 local exec_capture = helpers.exec_capture
 local eval = helpers.eval
@@ -152,79 +151,6 @@ describe('List support code', function()
   end)
 end)
 
--- oldtest: Test_deep_nest()
-it('Error when if/for/while/try/function is nested too deep',function()
-  clear()
-  local screen = Screen.new(80, 24)
-  screen:attach()
-  meths.set_option('laststatus', 2)
-  exec([[
-    " Deep nesting of if ... endif
-    func Test1()
-      let @a = join(repeat(['if v:true'], 51), "\n")
-      let @a ..= "\n"
-      let @a ..= join(repeat(['endif'], 51), "\n")
-      @a
-      let @a = ''
-    endfunc
-
-    " Deep nesting of for ... endfor
-    func Test2()
-      let @a = join(repeat(['for i in [1]'], 51), "\n")
-      let @a ..= "\n"
-      let @a ..= join(repeat(['endfor'], 51), "\n")
-      @a
-      let @a = ''
-    endfunc
-
-    " Deep nesting of while ... endwhile
-    func Test3()
-      let @a = join(repeat(['while v:true'], 51), "\n")
-      let @a ..= "\n"
-      let @a ..= join(repeat(['endwhile'], 51), "\n")
-      @a
-      let @a = ''
-    endfunc
-
-    " Deep nesting of try ... endtry
-    func Test4()
-      let @a = join(repeat(['try'], 51), "\n")
-      let @a ..= "\necho v:true\n"
-      let @a ..= join(repeat(['endtry'], 51), "\n")
-      @a
-      let @a = ''
-    endfunc
-
-    " Deep nesting of function ... endfunction
-    func Test5()
-      let @a = join(repeat(['function X()'], 51), "\n")
-      let @a ..= "\necho v:true\n"
-      let @a ..= join(repeat(['endfunction'], 51), "\n")
-      @a
-      let @a = ''
-    endfunc
-  ]])
-  screen:expect({any = '%[No Name%]'})
-  feed(':call Test1()<CR>')
-  screen:expect({any = 'E579: '})
-  feed('<C-C>')
-  screen:expect({any = '%[No Name%]'})
-  feed(':call Test2()<CR>')
-  screen:expect({any = 'E585: '})
-  feed('<C-C>')
-  screen:expect({any = '%[No Name%]'})
-  feed(':call Test3()<CR>')
-  screen:expect({any = 'E585: '})
-  feed('<C-C>')
-  screen:expect({any = '%[No Name%]'})
-  feed(':call Test4()<CR>')
-  screen:expect({any = 'E601: '})
-  feed('<C-C>')
-  screen:expect({any = '%[No Name%]'})
-  feed(':call Test5()<CR>')
-  screen:expect({any = 'E1058: '})
-end)
-
 describe("uncaught exception", function()
   before_each(clear)
   after_each(function()