patch 8.2.1569: Vim9: fixes not tested; failure in getchangelist()

Problem:    Vim9: fixes for functions not tested; failure in getchangelist().
Solution:   Add tests. (closes #6813, closes #6815, closes #6817)

src/evalfunc.c

@@ -3081,12 +3081,7 @@ f_getchangelist(typval_T *argvars, typval_T *rettv)
     if (argvars[0].v_type == VAR_UNKNOWN)
 	buf = curbuf;
     else
-    {
+	buf = tv_get_buf_from_arg(&argvars[0]);
-	(void)tv_get_number(&argvars[0]);    // issue errmsg if type error
-	++emsg_off;
-	buf = tv_get_buf(&argvars[0], FALSE);
-	--emsg_off;
-    }
     if (buf == NULL)
 	return;
 

src/testdir/test_vim9_func.vim

@@ -1431,6 +1431,39 @@ def Test_setbufvar()
    assert_equal(123, getbufvar('%', 'myvar'))
 enddef
 
+def Test_bufwinid()
+  let origwin = win_getid()
+  below split SomeFile
+  let SomeFileID = win_getid()
+  below split OtherFile
+  below split SomeFile
+  assert_equal(SomeFileID, bufwinid('SomeFile'))
+
+  win_gotoid(origwin)
+  only
+  bwipe SomeFile
+  bwipe OtherFile
+enddef
+
+def Test_getbufline()
+  e SomeFile
+  let buf = bufnr()
+  e #
+  let lines = ['aaa', 'bbb', 'ccc']
+  setbufline(buf, 1, lines)
+  assert_equal(lines, getbufline('#', 1, '$'))
+
+  bwipe!
+enddef
+
+def Test_getchangelist()
+  new
+  setline(1, 'some text')
+  let changelist = bufnr()->getchangelist()
+  assert_equal(changelist, getchangelist('%'))
+  bwipe!
+enddef
+
 def Test_setreg()
   setreg('a', ['aaa', 'bbb', 'ccc'])
   let reginfo = getreginfo('a')

src/version.c

@@ -754,6 +754,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1569,
 /**/
     1568,
 /**/