vim-patch:9.0.1345: too many "else if" statements for handling options

Problem:    Too many "else if" statements for handling options.
Solution:   Add more functions to handle options. (Yegappan Lakshmanan,
            closes vim/vim#12051)

8ad862a1f9

src/nvim/options.lua

@@ -196,7 +196,8 @@ return {
       type='string', list='comma', scope={'global'},
       deny_duplicates=true,
       varname='p_bo',
-      defaults={if_true="all"}
+      defaults={if_true="all"},
+      cb='did_set_belloff'
     },
     {
       full_name='binary', abbreviation='bin',
@@ -256,7 +257,8 @@ return {
       noglob=true,
       alloced=true,
       varname='p_bh',
-      defaults={if_true=""}
+      defaults={if_true=""},
+      cb='did_set_bufhidden'
     },
     {
       full_name='buflisted', abbreviation='bl',
@@ -283,7 +285,8 @@ return {
       type='string', list='onecomma', scope={'global'},
       deny_duplicates=true,
       varname='p_cmp',
-      defaults={if_true="internal,keepascii"}
+      defaults={if_true="internal,keepascii"},
+      cb='did_set_casemap'
     },
     {
       full_name='cdhome', abbreviation='cdh',
@@ -378,7 +381,8 @@ return {
       type='string', list='onecomma', scope={'global'},
       deny_duplicates=true,
       varname='p_cb',
-      defaults={if_true=""}
+      defaults={if_true=""},
+      cb='did_set_clipboard'
     },
     {
       full_name='cmdheight', abbreviation='ch',
@@ -402,7 +406,8 @@ return {
       type='string', list='onecomma', scope={'window'},
       deny_duplicates=true,
       redraw={'current_window'},
-      defaults={if_true=""}
+      defaults={if_true=""},
+      cb='did_set_colorcolumn'
     },
     {
       full_name='columns', abbreviation='co',
@@ -542,14 +547,16 @@ return {
       type='string', list='onecomma', scope={'window'},
       deny_duplicates=true,
       redraw={'current_window_only'},
-      defaults={if_true="both"}
+      defaults={if_true="both"},
+      cb='did_set_cursorlineopt'
     },
     {
       full_name='debug',
       short_desc=N_("to \"msg\" to see all error messages"),
       type='string', scope={'global'},
       varname='p_debug',
-      defaults={if_true=""}
+      defaults={if_true=""},
+      cb='did_set_debug'
     },
     {
       full_name='define', abbreviation='def',
@@ -638,7 +645,8 @@ return {
       short_desc=N_("in which direction 'equalalways' works"),
       type='string', scope={'global'},
       varname='p_ead',
-      defaults={if_true="both"}
+      defaults={if_true="both"},
+      cb='did_set_eadirection'
     },
     {
       full_name='edcompatible', abbreviation='ed',
@@ -784,7 +792,8 @@ return {
       type='string', list='onecomma', scope={'global'},
       deny_duplicates=true,
       varname='p_ffs',
-      defaults={if_true=macros('DFLT_FFS_VIM')}
+      defaults={if_true=macros('DFLT_FFS_VIM')},
+      cb='did_set_fileformats'
     },
     {
       full_name='fileignorecase', abbreviation='fic',
@@ -834,7 +843,8 @@ return {
       deny_duplicates=true,
       redraw={'current_window'},
       varname='p_fcl',
-      defaults={if_true=""}
+      defaults={if_true=""},
+      cb='did_set_foldclose'
     },
     {
       full_name='foldcolumn', abbreviation='fdc',
@@ -928,7 +938,8 @@ return {
       deny_duplicates=true,
       redraw={'curswant'},
       varname='p_fdo',
-      defaults={if_true="block,hor,mark,percent,quickfix,search,tag,undo"}
+      defaults={if_true="block,hor,mark,percent,quickfix,search,tag,undo"},
+      cb='did_set_foldopen'
     },
     {
       full_name='foldtext', abbreviation='fdt',
@@ -1193,7 +1204,8 @@ return {
       short_desc=N_("Live preview of substitution"),
       type='string', scope={'global'},
       varname='p_icm',
-      defaults={if_true="nosplit"}
+      defaults={if_true="nosplit"},
+      cb='did_set_inccommand'
     },
     {
       full_name='include', abbreviation='inc',
@@ -1308,7 +1320,8 @@ return {
       type='string', list='onecomma', scope={'global'},
       deny_duplicates=true,
       varname='p_jop',
-      defaults={if_true=''}
+      defaults={if_true=''},
+      cb='did_set_jumpoptions'
     },
     {
       full_name='keymap', abbreviation='kmp',
@@ -1632,7 +1645,8 @@ return {
       short_desc=N_("changes meaning of mouse buttons"),
       type='string', scope={'global'},
       varname='p_mousem',
-      defaults={if_true="popup_setpos"}
+      defaults={if_true="popup_setpos"},
+      cb='did_set_mousemodel'
     },
     {
       full_name='mousemoveevent', abbreviation='mousemev',
@@ -1871,7 +1885,8 @@ return {
       short_desc=N_("Changes the way redrawing works (debug)"),
       type='string', list='onecomma', scope={'global'},
       varname='p_rdb',
-      defaults={if_true=''}
+      defaults={if_true=''},
+      cb='did_set_redrawdebug'
     },
     {
       full_name='redrawtime', abbreviation='rdt',
@@ -2006,7 +2021,8 @@ return {
       type='string', list='onecomma', scope={'global'},
       deny_duplicates=true,
       varname='p_sbo',
-      defaults={if_true="ver,jump"}
+      defaults={if_true="ver,jump"},
+      cb='did_set_scrollopt'
     },
     {
       full_name='sections', abbreviation='sect',
@@ -2037,7 +2053,8 @@ return {
       type='string', list='onecomma', scope={'global'},
       deny_duplicates=true,
       varname='p_slm',
-      defaults={if_true=""}
+      defaults={if_true=""},
+      cb='did_set_selectmode'
     },
     {
       full_name='sessionoptions', abbreviation='ssop',
@@ -2203,7 +2220,8 @@ return {
       short_desc=N_("change location of partial command"),
       type='string', scope={'global'},
       varname='p_sloc',
-      defaults={if_true="last"}
+      defaults={if_true="last"},
+      cb='did_set_showcmdloc'
     },
     {
       full_name='showfulltag', abbreviation='sft',
@@ -2362,7 +2380,8 @@ return {
       short_desc=N_("determines scroll behavior for split windows"),
       type='string', scope={'global'},
       varname='p_spk',
-      defaults={if_true='cursor'}
+      defaults={if_true='cursor'},
+      cb='did_set_splitkeep'
     },
     {
       full_name='splitright', abbreviation='spr',
@@ -2432,7 +2451,8 @@ return {
       type='string', list='onecomma', scope={'global'},
       deny_duplicates=true,
       varname='p_swb',
-      defaults={if_true="uselast"}
+      defaults={if_true="uselast"},
+      cb='did_set_switchbuf'
     },
     {
       full_name='synmaxcol', abbreviation='smc',
@@ -2559,7 +2579,8 @@ return {
       type='string', list='onecomma', scope={'global'},
       deny_duplicates=true,
       varname='p_tpf',
-      defaults={if_true="BS,HT,ESC,DEL"}
+      defaults={if_true="BS,HT,ESC,DEL"},
+      cb='did_set_termpastefilter'
     },
     {
       full_name='terse',
@@ -2774,7 +2795,8 @@ return {
       type='string', list='onecomma', scope={'global'},
       deny_duplicates=true,
       varname='p_vop',
-      defaults={if_true="folds,cursor,curdir"}
+      defaults={if_true="folds,cursor,curdir"},
+      cb='did_set_viewoptions'
     },
     {
       -- Alias for "shada".
@@ -2870,7 +2892,8 @@ return {
       type='string', list='onecomma', scope={'global'},
       deny_duplicates=true,
       varname='p_wop',
-      defaults={if_true='pum,tagfile'}
+      defaults={if_true='pum,tagfile'},
+      cb='did_set_wildoptions'
     },
     {
       full_name='winaltkeys', abbreviation='wak',

src/nvim/optionstr.c

@@ -698,6 +698,18 @@ const char *did_set_backupext_or_patchmode(optset_T *args FUNC_ATTR_UNUSED)
   return NULL;
 }
 
+/// The 'belloff' option is changed.
+const char *did_set_belloff(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_flags(p_bo, p_bo_values, &bo_flags, true);
+}
+
+/// The 'termpastefilter' option is changed.
+const char *did_set_termpastefilter(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_flags(p_tpf, p_tpf_values, &tpf_flags, true);
+}
+
 /// The 'breakindentopt' option is changed.
 const char *did_set_breakindentopt(optset_T *args)
 {
@@ -740,11 +752,15 @@ const char *did_set_helpfile(optset_T *args FUNC_ATTR_UNUSED)
 }
 
 /// The 'cursorlineopt' option is changed.
-static void did_set_cursorlineopt(win_T *win, char **varp, const char **errmsg)
+const char *did_set_cursorlineopt(optset_T *args)
 {
-  if (**varp == NUL || fill_culopt_flags(*varp, win) != OK) {
+  win_T *win = (win_T *)args->os_win;
-    *errmsg = e_invarg;
+
+  if (*args->os_varp == NUL || fill_culopt_flags(args->os_varp, win) != OK) {
+    return e_invarg;
   }
+
+  return NULL;
 }
 
 /// The 'helplang' option is changed.
@@ -771,17 +787,29 @@ const char *did_set_highlight(optset_T *args)
   return NULL;
 }
 
-static void did_set_opt_flags(char *val, char **values, unsigned *flagp, bool list,
+static const char *did_set_opt_flags(char *val, char **values, unsigned *flagp, bool list)
-                              const char **errmsg)
 {
   if (opt_strings_flags(val, values, flagp, list) != OK) {
-    *errmsg = e_invarg;
+    return e_invarg;
   }
+  return NULL;
 }
 
-static void did_set_opt_strings(char *val, char **values, bool list, const char **errmsg)
+static const char *did_set_opt_strings(char *val, char **values, bool list)
 {
-  did_set_opt_flags(val, values, NULL, list, errmsg);
+  return did_set_opt_flags(val, values, NULL, list);
+}
+
+/// The 'selectmode' option is changed.
+const char *did_set_selectmode(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_strings(p_slm, p_slm_values, true);
+}
+
+/// The 'inccommand' option is changed.
+const char *did_set_inccommand(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_strings(p_icm, p_icm_values, false);
 }
 
 /// The 'sessionoptions' option is changed.
@@ -832,6 +860,18 @@ const char *did_set_background(optset_T *args FUNC_ATTR_UNUSED)
   return NULL;
 }
 
+/// The 'clipboard' option is changed.
+const char *did_set_clipboard(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_flags(p_cb, p_cb_values, &cb_flags, true);
+}
+
+/// The 'foldopen' option is changed.
+const char *did_set_foldopen(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_flags(p_fdo, p_fdo_values, &fdo_flags, true);
+}
+
 /// The 'wildmode' option is changed.
 const char *did_set_wildmode(optset_T *args FUNC_ATTR_UNUSED)
 {
@@ -859,6 +899,12 @@ const char *did_set_eventignore(optset_T *args FUNC_ATTR_UNUSED)
   return NULL;
 }
 
+/// The 'eadirection' option is changed.
+const char *did_set_eadirection(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_strings(p_ead, p_ead_values, false);
+}
+
 // 'encoding', 'fileencoding' and 'makeencoding'
 static void did_set_encoding(buf_T *buf, char **varp, char **gvarp, int opt_flags,
                              const char **errmsg)
@@ -965,6 +1011,12 @@ const char *did_set_fileformat(optset_T *args)
   return NULL;
 }
 
+/// The 'fileformats' option is changed.
+const char *did_set_fileformats(optset_T *args)
+{
+  return did_set_opt_strings(p_ffs, p_ff_values, true);
+}
+
 /// The 'matchpairs' option is changed.
 const char *did_set_matchpairs(optset_T *args)
 {
@@ -999,6 +1051,13 @@ const char *did_set_cinoptions(optset_T *args FUNC_ATTR_UNUSED)
   return NULL;
 }
 
+/// The 'colorcolumn' option is changed.
+const char *did_set_colorcolumn(optset_T *args)
+{
+  win_T *win = (win_T *)args->os_win;
+  return check_colorcolumn(win);
+}
+
 static void did_set_comments(char **varp, char *errbuf, size_t errbuflen, const char **errmsg)
 {
   for (char *s = *varp; *s;) {
@@ -1064,6 +1123,12 @@ const char *did_set_verbosefile(optset_T *args)
   return NULL;
 }
 
+/// The 'viewoptions' option is changed.
+const char *did_set_viewoptions(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_flags(p_vop, p_ssop_values, &vop_flags, true);
+}
+
 static int shada_idx = -1;
 
 static const char *did_set_shada(vimoption_T **opt, int *opt_idx, bool *free_oldval, char *errbuf,
@@ -1241,7 +1306,13 @@ const char *did_set_spellsuggest(optset_T *args FUNC_ATTR_UNUSED)
   return NULL;
 }
 
- /// The 'mkspellmem' option is changed.
+/// The 'splitkeep' option is changed.
+const char *did_set_splitkeep(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_strings(p_spk, p_spk_values, false);
+}
+
+/// The 'mkspellmem' option is changed.
 const char *did_set_mkspellmem(optset_T *args FUNC_ATTR_UNUSED)
 {
   if (spell_check_msm() != OK) {
@@ -1250,6 +1321,19 @@ const char *did_set_mkspellmem(optset_T *args FUNC_ATTR_UNUSED)
   return NULL;
 }
 
+/// The 'mousemodel' option is changed.
+const char *did_set_mousemodel(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_strings(p_mousem, p_mousem_values, false);
+}
+
+/// The 'bufhidden' option is changed.
+const char *did_set_bufhidden(optset_T *args)
+{
+  buf_T *buf = (buf_T *)args->os_buf;
+  return did_set_opt_strings(buf->b_p_bh, p_bufhidden_values, false);
+}
+
 /// The 'buftype' option is changed.
 const char *did_set_buftype(optset_T *args)
 {
@@ -1270,6 +1354,12 @@ const char *did_set_buftype(optset_T *args)
   return NULL;
 }
 
+/// The 'casemap' option is changed.
+const char *did_set_casemap(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_flags(p_cmp, p_cmp_values, &cmp_flags, true);
+}
+
 /// The 'statusline', 'winbar', 'tabline', 'rulerformat' or 'statuscolumn' option is changed.
 ///
 /// @param rulerformat  true if the 'rulerformat' option is changed
@@ -1338,6 +1428,12 @@ const char *did_set_statuscolumn(optset_T *args)
   return did_set_statustabline_rulerformat(args, false, true);
 }
 
+/// The 'scrollopt' option is changed.
+const char *did_set_scrollopt(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_strings(p_sbo, p_scbopt_values, true);
+}
+
 static void did_set_complete(char **varp, char *errbuf, size_t errbuflen, const char **errmsg)
 {
   // check if it is a valid value for 'complete' -- Acevedo
@@ -1399,6 +1495,12 @@ const char *did_set_completeslash(optset_T *args)
 }
 #endif
 
+/// The 'showcmdloc' option is changed.
+const char *did_set_showcmdloc(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_strings(p_sloc, p_sloc_values, true);
+}
+
 /// The 'signcolumn' option is changed.
 const char *did_set_signcolumn(optset_T *args)
 {
@@ -1439,6 +1541,12 @@ const char *did_set_backspace(optset_T *args FUNC_ATTR_UNUSED)
   return NULL;
 }
 
+/// The 'switchbuf' option is changed.
+const char *did_set_switchbuf(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_flags(p_swb, p_swb_values, &swb_flags, true);
+}
+
 /// The 'tagcase' option is changed.
 const char *did_set_tagcase(optset_T *args)
 {
@@ -1466,6 +1574,12 @@ const char *did_set_tagcase(optset_T *args)
   return NULL;
 }
 
+/// The 'debug' option is changed.
+const char *did_set_debug(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_strings(p_debug, p_debug_values, false);
+}
+
 /// The 'diffopt' option is changed.
 const char *did_set_diffopt(optset_T *args FUNC_ATTR_UNUSED)
 {
@@ -1560,6 +1674,24 @@ const char *did_set_virtualedit(optset_T *args)
   return NULL;
 }
 
+/// The 'jumpoptions' option is changed.
+const char *did_set_jumpoptions(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_flags(p_jop, p_jop_values, &jop_flags, true);
+}
+
+/// The 'redrawdebug' option is changed.
+const char *did_set_redrawdebug(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_flags(p_rdb, p_rdb_values, &rdb_flags, true);
+}
+
+/// The 'wildoptions' option is changed.
+const char *did_set_wildoptions(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_flags(p_wop, p_wop_values, &wop_flags, true);
+}
+
 /// The 'lispoptions' option is changed.
 const char *did_set_lispoptions(optset_T *args)
 {
@@ -1657,6 +1789,12 @@ const char *did_set_vartabstop(optset_T *args)
   return NULL;
 }
 
+/// The 'nrformats' option is changed.
+const char *did_set_nrformats(optset_T *args)
+{
+  return did_set_opt_strings(args->os_varp, p_nf_values, true);
+}
+
 static void did_set_optexpr(char **varp)
 {
   char *name = get_scriptlocal_funcname(*varp);
@@ -1666,6 +1804,12 @@ static void did_set_optexpr(char **varp)
   }
 }
 
+/// The 'foldclose' option is changed.
+const char *did_set_foldclose(optset_T *args FUNC_ATTR_UNUSED)
+{
+  return did_set_opt_strings(p_fcl, p_fcl_values, true);
+}
+
 // handle option that is a list of flags.
 static void did_set_option_listflag(char **varp, char *flags, char *errbuf, size_t errbuflen,
                                     const char **errmsg)
@@ -1776,30 +1920,12 @@ static const char *did_set_string_option_for(buf_T *buf, win_T *win, int opt_idx
              || varp == &p_isp                          // 'isprint'
              || varp == &p_isf) {                       // 'isfname'
     did_set_isopt(buf, &did_chartab, &errmsg);
-  } else if (gvarp == &win->w_allbuf_opt.wo_culopt) {   // 'cursorlineopt'
-    did_set_cursorlineopt(win, varp, &errmsg);
-  } else if (varp == &win->w_p_cc) {                    // 'colorcolumn'
-    errmsg = check_colorcolumn(win);
-  } else if (varp == &p_jop) {                          // 'jumpoptions'
-    did_set_opt_flags(p_jop, p_jop_values, &jop_flags, true, &errmsg);
-  } else if (gvarp == &p_nf) {                          // 'nrformats'
-    did_set_opt_strings(*varp, p_nf_values, true, &errmsg);
-  } else if (varp == &p_vop) {                          // 'viewoptions'
-    did_set_opt_flags(p_vop, p_ssop_values, &vop_flags, true, &errmsg);
-  } else if (varp == &p_rdb) {                          // 'redrawdebug'
-    did_set_opt_flags(p_rdb, p_rdb_values, &rdb_flags, true, &errmsg);
-  } else if (varp == &p_sbo) {                          // 'scrollopt'
-    did_set_opt_strings(p_sbo, p_scbopt_values, true, &errmsg);
-  } else if (varp == &p_wop) {                          // 'wildoptions'
-    did_set_opt_flags(p_wop, p_wop_values, &wop_flags, true, &errmsg);
   } else if (varp == &p_enc                             // 'encoding'
              || gvarp == &p_fenc                        // 'fileencoding'
              || gvarp == &p_menc) {                     // 'makeencoding'
     did_set_encoding(buf, varp, gvarp, opt_flags, &errmsg);
   } else if (varp == &buf->b_p_keymap) {                // 'keymap'
     did_set_keymap(buf, varp, opt_flags, value_checked, &errmsg);
-  } else if (varp == &p_ffs) {                          // 'fileformats'
-    did_set_opt_strings(p_ffs, p_ff_values, true, &errmsg);
   } else if (gvarp == &p_com) {                         // 'comments'
     did_set_comments(varp, errbuf, errbuflen, &errmsg);
   } else if (varp == &p_lcs                             // global 'listchars'
@@ -1811,41 +1937,11 @@ static const char *did_set_string_option_for(buf_T *buf, win_T *win, int opt_idx
     errmsg = set_chars_option(win, varp, true);
   } else if (varp == &p_shada) {                        // 'shada'
     errmsg = did_set_shada(&opt, &opt_idx, &free_oldval, errbuf, errbuflen);
-  } else if (varp == &p_slm) {                          // 'selectmode'
-    did_set_opt_strings(p_slm, p_slm_values, true, &errmsg);
-  } else if (varp == &p_mousem) {                       // 'mousemodel'
-    did_set_opt_strings(p_mousem, p_mousem_values, false, &errmsg);
-  } else if (varp == &p_swb) {                          // 'switchbuf'
-    did_set_opt_flags(p_swb, p_swb_values, &swb_flags, true, &errmsg);
-  } else if (varp == &p_spk) {                          // 'splitkeep'
-    did_set_opt_strings(p_spk, p_spk_values, false, &errmsg);
-  } else if (varp == &p_debug) {                        // 'debug'
-    did_set_opt_strings(p_debug, p_debug_values, true, &errmsg);
-  } else if (varp == &p_ead) {                          // 'eadirection'
-    did_set_opt_strings(p_ead, p_ead_values, false, &errmsg);
-  } else if (varp == &p_cb) {                           // 'clipboard'
-    did_set_opt_flags(p_cb, p_cb_values, &cb_flags, true, &errmsg);
-  } else if (gvarp == &p_bh) {                          // 'bufhidden'
-    did_set_opt_strings(buf->b_p_bh, p_bufhidden_values, false, &errmsg);
   } else if (gvarp == &p_cpt) {                         // 'complete'
     did_set_complete(varp, errbuf, errbuflen, &errmsg);
-  } else if (varp == &p_sloc) {                         // 'showcmdloc'
-    did_set_opt_strings(*varp, p_sloc_values, false, &errmsg);
-  } else if (varp == &p_bo) {
-    did_set_opt_flags(p_bo, p_bo_values, &bo_flags, true, &errmsg);
-  } else if (varp == &p_cmp) {                          // 'casemap'
-    did_set_opt_flags(p_cmp, p_cmp_values, &cmp_flags, true, &errmsg);
-  } else if (varp == &p_fdo) {                          // 'foldopen'
-    did_set_opt_flags(p_fdo, p_fdo_values, &fdo_flags, true, &errmsg);
-  } else if (varp == &p_fcl) {                          // 'foldclose'
-    did_set_opt_strings(*varp, p_fcl_values, true, &errmsg);
-  } else if (varp == &p_icm) {                          // 'inccommand'
-    did_set_opt_strings(*varp, p_icm_values, false, &errmsg);
   } else if (gvarp == &p_ft                             // 'filetype'
              || gvarp == &p_syn) {                      // 'syntax'
     did_set_filetype_or_syntax(varp, oldval, value_checked, &value_changed, &errmsg);
-  } else if (varp == &p_tpf) {
-    did_set_opt_flags(p_tpf, p_tpf_values, &tpf_flags, true, &errmsg);
   } else if (varp == &p_dex                             // 'diffexpr'
              || gvarp == &win->w_allbuf_opt.wo_fde      // 'foldexpr'
              || gvarp == &win->w_allbuf_opt.wo_fdt      // 'foldtext'

test/old/testdir/test_options.vim

@@ -396,7 +396,16 @@ func Test_set_errors()
   if has('mouseshape')
     call assert_fails('se mouseshape=i-r:x', 'E547:')
   endif
-  call assert_fails('set backupext=~ patchmode=~', 'E589:')
+
+  " Test for 'backupext' and 'patchmode' set to the same value
+  set backupext=.bak
+  set patchmode=.patch
+  call assert_fails('set patchmode=.bak', 'E589:')
+  call assert_equal('.patch', &patchmode)
+  call assert_fails('set backupext=.patch', 'E589:')
+  call assert_equal('.bak', &backupext)
+  set backupext& patchmode&
+
   call assert_fails('set winminheight=10 winheight=9', 'E591:')
   call assert_fails('set winminwidth=10 winwidth=9', 'E592:')
   call assert_fails("set showbreak=\x01", 'E595:')
@@ -1344,4 +1353,74 @@ func Test_set_min_lines_columns()
   let &columns = save_columns
 endfunc
 
+" Test for reverting a string option value if the new value is invalid.
+func Test_string_option_revert_on_failure()
+  new
+  let optlist = [
+        \ ['ambiwidth', 'double', 'a123'],
+        \ ['background', 'dark', 'a123'],
+        \ ['backspace', 'eol', 'a123'],
+        \ ['backupcopy', 'no', 'a123'],
+        \ ['belloff', 'showmatch', 'a123'],
+        \ ['breakindentopt', 'min:10', 'list'],
+        \ ['bufhidden', 'wipe', 'a123'],
+        \ ['buftype', 'nowrite', 'a123'],
+        \ ['casemap', 'keepascii', 'a123'],
+        \ ['cedit', "\<C-Y>", 'z'],
+        \ ['colorcolumn', '10', 'z'],
+        \ ['commentstring', '#%s', 'a123'],
+        \ ['complete', '.,t', 'a'],
+        \ ['completefunc', 'MyCmplFunc', '1a-'],
+        "\ ['completeopt', 'popup', 'a123'],
+        \ ['completeopt', 'preview', 'a123'],
+        "\ ['completepopup', 'width:20', 'border'],
+        \ ['concealcursor', 'v', 'xyz'],
+        "\ ['cpoptions', 'HJ', '~'],
+        \ ['cpoptions', 'J', '~'],
+        "\ ['cryptmethod', 'zip', 'a123'],
+        \ ['cursorlineopt', 'screenline', 'a123'],
+        \ ['debug', 'throw', 'a123'],
+        \ ['diffopt', 'iwhite', 'a123'],
+        \ ['display', 'uhex', 'a123'],
+        \ ['eadirection', 'hor', 'a123'],
+        \ ['encoding', 'utf-8', 'a123'],
+        \ ['eventignore', 'TextYankPost', 'a123'],
+        \ ['fileencoding', 'utf-8', 'a123,'],
+        \ ['fileformat', 'mac', 'a123'],
+        \ ['fileformats', 'mac', 'a123'],
+        \ ['fillchars', 'diff:~', 'a123'],
+        \ ['foldclose', 'all', 'a123'],
+        \ ['foldmarker', '[[[,]]]', '[[['],
+        \ ['foldmethod', 'marker', 'a123'],
+        \ ['foldopen', 'percent', 'a123'],
+        \ ['formatoptions', 'an', '*'],
+        \ ['guicursor', 'n-v-c:block-Cursor/lCursor', 'n-v-c'],
+        \ ['helplang', 'en', 'a'],
+        "\ ['highlight', '!:CursorColumn', '8:']
+        \ ]
+  if has('gui')
+    call add(optlist, ['browsedir', 'buffer', 'a123'])
+  endif
+  if has('clipboard_working')
+    call add(optlist, ['clipboard', 'unnamed', 'a123'])
+  endif
+  if has('win32')
+    call add(optlist, ['completeslash', 'slash', 'a123'])
+  endif
+  if has('cscope')
+    call add(optlist, ['cscopequickfix', 't-', 'z-'])
+  endif
+  if !has('win32') && !has('nvim')
+    call add(optlist, ['imactivatefunc', 'MyCmplFunc', '1a-'])
+  endif
+  for opt in optlist
+    exe $"let save_opt = &{opt[0]}"
+    exe $"let &{opt[0]} = '{opt[1]}'"
+    call assert_fails($"let &{opt[0]} = '{opt[2]}'", '', opt[0])
+    call assert_equal(opt[1], eval($"&{opt[0]}"), opt[0])
+    exe $"let &{opt[0]} = save_opt"
+  endfor
+  bw!
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab