vim-patch:9.1.1544: :retab cannot be limited to indentation only (#34939)

Problem:  :retab cannot be limited to indentation only
Solution: add the optional -indentonly parameter
          (Hirohito Higashi)

closes: vim/vim#17730

836e54f5de

Co-authored-by: Hirohito Higashi <h.east.727@gmail.com>

src/nvim/cmdexpand.c

@@ -2290,6 +2290,11 @@ static const char *set_context_by_cmdname(const char *cmd, cmdidx_T cmdidx, expa
     xp->xp_pattern = (char *)arg;
     break;
 
+  case CMD_retab:
+    xp->xp_context = EXPAND_RETAB;
+    xp->xp_pattern = (char *)arg;
+    break;
+
   case CMD_messages:
     xp->xp_context = EXPAND_MESSAGES;
     xp->xp_pattern = (char *)arg;
@@ -2768,6 +2773,16 @@ static char *get_scriptnames_arg(expand_T *xp FUNC_ATTR_UNUSED, int idx)
   return NameBuff;
 }
 
+/// Function given to ExpandGeneric() to obtain the possible arguments of the
+/// ":retab {-indentonly}" option.
+static char *get_retab_arg(expand_T *xp FUNC_ATTR_UNUSED, int idx)
+{
+  if (idx == 0) {
+    return "-indentonly";
+  }
+  return NULL;
+}
+
 /// Function given to ExpandGeneric() to obtain the possible arguments of the
 /// ":messages {clear}" command.
 static char *get_messages_arg(expand_T *xp FUNC_ATTR_UNUSED, int idx)
@@ -2853,6 +2868,7 @@ static int ExpandOther(char *pat, expand_T *xp, regmatch_T *rmp, char ***matches
     { EXPAND_ARGLIST, get_arglist_name, true, false },
     { EXPAND_BREAKPOINT, get_breakadd_arg, true, true },
     { EXPAND_SCRIPTNAMES, get_scriptnames_arg, true, false },
+    { EXPAND_RETAB, get_retab_arg, true, true },
     { EXPAND_CHECKHEALTH, get_healthcheck_names, true, false },
   };
   int ret = FAIL;

src/nvim/cmdexpand_defs.h

@@ -114,6 +114,7 @@ enum {
   EXPAND_FINDFUNC,
   EXPAND_FILETYPECMD,
   EXPAND_PATTERN_IN_BUF,
+  EXPAND_RETAB,
   EXPAND_CHECKHEALTH,
   EXPAND_LUA,
 };

src/nvim/eval.lua

@@ -3901,6 +3901,7 @@ M.funcs = {
       messages	|:messages| suboptions
       option		options
       packadd		optional package |pack-add| names
+      retab		|:retab| suboptions
       runtime		|:runtime| completion
       scriptnames	sourced script names |:scriptnames|
       shellcmd	Shell command

src/nvim/indent.c

@@ -1006,16 +1006,23 @@ void ex_retab(exarg_T *eap)
 
   linenr_T first_line = 0;              // first changed line
   linenr_T last_line = 0;               // last changed line
+  bool is_indent_only = false;
 
   int save_list = curwin->w_p_list;
   curwin->w_p_list = 0;             // don't want list mode here
 
-  new_ts_str = eap->arg;
-  if (!tabstop_set(eap->arg, &new_vts_array)) {
+  char *ptr = eap->arg;
+  if (strncmp(ptr, "-indentonly", 11) == 0 && ascii_iswhite_or_nul(ptr[11])) {
+    is_indent_only = true;
+    ptr = skipwhite(ptr + 11);
+  }
+
+  new_ts_str = ptr;
+  if (!tabstop_set(ptr, &new_vts_array)) {
     return;
   }
-  while (ascii_isdigit(*(eap->arg)) || *(eap->arg) == ',') {
-    eap->arg++;
+  while (ascii_isdigit(*ptr) || *ptr == ',') {
+    ptr++;
   }
 
   // This ensures that either new_vts_array and new_ts_str are freshly
@@ -1025,10 +1032,10 @@ void ex_retab(exarg_T *eap)
     new_vts_array = curbuf->b_p_vts_array;
     new_ts_str = NULL;
   } else {
-    new_ts_str = xmemdupz(new_ts_str, (size_t)(eap->arg - new_ts_str));
+    new_ts_str = xmemdupz(new_ts_str, (size_t)(ptr - new_ts_str));
   }
   for (linenr_T lnum = eap->line1; !got_int && lnum <= eap->line2; lnum++) {
-    char *ptr = ml_get(lnum);
+    ptr = ml_get(lnum);
     int old_len = ml_get_len(lnum);
     int col = 0;
     int64_t vcol = 0;
@@ -1106,6 +1113,10 @@ void ex_retab(exarg_T *eap)
         }
         got_tab = false;
         num_spaces = 0;
+
+        if (is_indent_only) {
+          break;
+        }
       }
       if (ptr[col] == NUL) {
         break;

src/nvim/usercmd.c

@@ -90,6 +90,7 @@ static const char *command_complete[] = {
   [EXPAND_SYNTIME] = "syntime",
   [EXPAND_SETTINGS] = "option",
   [EXPAND_PACKADD] = "packadd",
+  [EXPAND_RETAB] = "retab",
   [EXPAND_RUNTIME] = "runtime",
   [EXPAND_SHELLCMD] = "shellcmd",
   [EXPAND_SHELLCMDLINE] = "shellcmdline",