vim-patch:8.0.0654: no warning for text after :endfunction

Problem:    Text found after :endfunction is silently ignored.
Solution:   Give a warning if 'verbose' is set.  When | or \n are used,
            execute the text as a command.
663bb23316

Note: the code part of this patch was addressed by 60c0252672.

src/nvim/testdir/test_vimscript.vim

@@ -1215,6 +1215,33 @@ func Test_bitwise_functions()
     call assert_fails("call invert({})", 'E728:')
 endfunc
 
+" Test trailing text after :endfunction				    {{{1
+func Test_endfunction_trailing()
+    call assert_false(exists('*Xtest'))
+
+    exe "func Xtest()\necho 'hello'\nendfunc\nlet done = 'yes'"
+    call assert_true(exists('*Xtest'))
+    call assert_equal('yes', done)
+    delfunc Xtest
+    unlet done
+
+    exe "func Xtest()\necho 'hello'\nendfunc|let done = 'yes'"
+    call assert_true(exists('*Xtest'))
+    call assert_equal('yes', done)
+    delfunc Xtest
+    unlet done
+
+    set verbose=1
+    exe "func Xtest()\necho 'hello'\nendfunc \" garbage"
+    call assert_true(exists('*Xtest'))
+    delfunc Xtest
+
+    call assert_fails("func Xtest()\necho 'hello'\nendfunc garbage", 'E946')
+    call assert_true(exists('*Xtest'))
+    delfunc Xtest
+    set verbose=0
+endfunc
+
 "-------------------------------------------------------------------------------
 " Modelines								    {{{1
 " vim: ts=8 sw=4 tw=80 fdm=marker