patch 8.2.2643: various code not covered by tests

Problem:    Various code not covered by tests.
Solution:   Add a few more test. (Yegappan Lakshmanan, closes #7995)

src/testdir/test_edit.vim

@@ -411,6 +411,33 @@ func Test_edit_13()
   bwipe!
 endfunc
 
+" Test for autoindent removing indent when insert mode is stopped.  Some parts
+" of the code is exercised only when interactive mode is used. So use Vim in a
+" terminal.
+func Test_autoindent_remove_indent()
+  CheckRunVimInTerminal
+  let buf = RunVimInTerminal('-N Xfile', {'rows': 6, 'cols' : 20})
+  call TermWait(buf)
+  call term_sendkeys(buf, ":set autoindent\n")
+  " leaving insert mode in a new line with indent added by autoindent, should
+  " remove the indent.
+  call term_sendkeys(buf, "i\<Tab>foo\<CR>\<Esc>")
+  " Need to delay for sometime, otherwise the code in getchar.c will not be
+  " exercised.
+  call TermWait(buf, 50)
+  " when a line is wrapped and the cursor is at the start of the second line,
+  " leaving insert mode, should move the cursor back to the first line.
+  call term_sendkeys(buf, "o" .. repeat('x', 20) .. "\<Esc>")
+  " Need to delay for sometime, otherwise the code in getchar.c will not be
+  " exercised.
+  call TermWait(buf, 50)
+  call term_sendkeys(buf, ":w\n")
+  call TermWait(buf)
+  call StopVimInTerminal(buf)
+  call assert_equal(["\tfoo", '', repeat('x', 20)], readfile('Xfile'))
+  call delete('Xfile')
+endfunc
+
 func Test_edit_CR()
   " Test for <CR> in insert mode
   " basically only in quickfix mode ist tested, the rest