vim-patch:8.0.0716: "--clean", 'shadafile' #9907

Nvim notes:
- Nvim does not support "-u DEFAULTS", that change is omitted.
- Also add 'shadafile' as an alias to 'viminfofile'.
- Deprecate 'viminfofile'.

Problem:    Not easy to start Vim cleanly without changing the viminfo file.
            Not possible to know whether the -i command line flag was used.
Solution:   Add the --clean command line argument.  Add the 'viminfofile'
            option.  Add "-u DEFAULTS".
c4da113ef9

src/nvim/globals.h

@@ -754,7 +754,6 @@ EXTERN int skip_redraw INIT(= FALSE);       /* skip redraw once */
 EXTERN int do_redraw INIT(= FALSE);         /* extra redraw once */
 
 EXTERN int need_highlight_changed INIT(= true);
-EXTERN char *used_shada_file INIT(= NULL);  // name of the ShaDa file to use
 
 EXTERN FILE *scriptout INIT(= NULL);  ///< Stream to write script to.
 

src/nvim/main.c

@@ -871,6 +871,9 @@ static void command_line_scan(mparm_T *parmp)
           } else if (STRNICMP(argv[0] + argv_idx, "startuptime", 11) == 0) {
             want_argument = true;
             argv_idx += 11;
+          } else if (STRNICMP(argv[0] + argv_idx, "clean", 5) == 0) {
+            parmp->use_vimrc = "NONE";
+            set_option_value("shadafile", 0L, "NONE", 0);
           } else {
             if (argv[0][argv_idx])
               mainerr(err_opt_unknown, argv[0]);
@@ -1129,7 +1132,7 @@ static void command_line_scan(mparm_T *parmp)
           }
 
           case 'i': {  // "-i {shada}" use for shada
-            used_shada_file = argv[0];
+            set_option_value("shadafile", 0L, argv[0], 0);
             break;
           }
 

src/nvim/option_defs.h

@@ -630,6 +630,7 @@ EXTERN long p_ur;               ///< 'undoreload'
 EXTERN long p_uc;               ///< 'updatecount'
 EXTERN long p_ut;               ///< 'updatetime'
 EXTERN char_u *p_shada;         ///< 'shada'
+EXTERN char *p_shadafile;       ///< 'shadafile'
 EXTERN char_u *p_vdir;          ///< 'viewdir'
 EXTERN char_u *p_vop;           ///< 'viewoptions'
 EXTERN unsigned vop_flags;      ///< uses SSOP_ flags

src/nvim/options.lua

@@ -2014,6 +2014,15 @@ return {
       varname='p_shada',
       defaults={if_true={vi="", vim="!,'100,<50,s10,h"}}
     },
+    {
+      full_name='shadafile', abbreviation='sdf',
+      type='string', list='onecomma', scope={'global'},
+      deny_duplicates=true,
+      vi_def=true,
+      secure=true,
+      varname='p_shadafile',
+      defaults={if_true={vi=""}}
+    },
     {
       full_name='shell', abbreviation='sh',
       type='string', scope={'global'},
@@ -2632,6 +2641,15 @@ return {
       varname='p_shada',
       defaults={if_true={vi="", vim="!,'100,<50,s10,h"}}
     },
+    {
+      full_name='viminfofile', abbreviation='vif',
+      type='string', list='onecomma', scope={'global'},
+      deny_duplicates=true,
+      vi_def=true,
+      secure=true,
+      varname='p_shadafile',
+      defaults={if_true={vi=""}}
+    },
     {
       full_name='virtualedit', abbreviation='ve',
       type='string', list='onecomma', scope={'global'},

src/nvim/shada.c

@@ -856,13 +856,13 @@ static int msgpack_sd_writer_write(void *data, const char *buf, size_t len)
   return 0;
 }
 
-/// Check whether writing to shada file was disabled with -i NONE
+/// Check whether writing to shada file was disabled ("-i NONE" or "--clean").
 ///
 /// @return true if it was disabled, false otherwise.
 static bool shada_disabled(void)
   FUNC_ATTR_PURE
 {
-  return used_shada_file != NULL && STRCMP(used_shada_file, "NONE") == 0;
+  return strequal(p_shadafile, "NONE");
 }
 
 /// Read ShaDa file
@@ -1542,14 +1542,14 @@ static char *shada_filename(const char *file)
   FUNC_ATTR_MALLOC FUNC_ATTR_NONNULL_RET FUNC_ATTR_WARN_UNUSED_RESULT
 {
   if (file == NULL || *file == NUL) {
-    if (used_shada_file != NULL) {
-      file = used_shada_file;
+    if (p_shadafile != NULL) {
+      file = p_shadafile;
     } else {
       if ((file = find_shada_parameter('n')) == NULL || *file == NUL) {
         file =  shada_get_default_file();
       }
       // XXX It used to be one level lower, so that whatever is in
-      //     `used_shada_file` was expanded. I intentionally moved it here
+      //     `p_shadafile` was expanded. I intentionally moved it here
       //     because various expansions must have already be done by the shell.
       //     If shell is not performing them then they should be done in main.c
       //     where arguments are parsed, *not here*.