Merge #6737 "options: make 'highlight' read-only"

3 files changed, 77 insertions, 125 deletions

diff --git a/src/nvim/globals.h b/src/nvim/globals.h
index b820965680..a3657f2122 100644
--- a/src/nvim/globals.h
+++ b/src/nvim/globals.h
@@ -413,8 +413,7 @@ EXTERN int no_check_timestamps INIT(= 0);       /* Don't check timestamps */
 
 /*
  * Values for index in highlight_attr[].
- * When making changes, also update HL_FLAGS below!  And update the default
- * value of 'highlight' in option.c.
+ * When making changes, also update hlf_names below!
  */
 typedef enum {
   HLF_8 = 0         /* Meta & special keys listed with ":map", text that is
@@ -447,8 +446,8 @@ typedef enum {
   , HLF_CHD         // Changed diff line
   , HLF_DED         // Deleted diff line
   , HLF_TXD         // Text Changed in diff line
-  , HLF_CONCEAL     // Concealed text
   , HLF_SC          // Sign column
+  , HLF_CONCEAL     // Concealed text
   , HLF_SPB         // SpellBad
   , HLF_SPC         // SpellCap
   , HLF_SPR         // SpellRare
@@ -469,12 +468,56 @@ typedef enum {
   , HLF_COUNT       // MUST be the last one
 } hlf_T;
 
-/* The HL_FLAGS must be in the same order as the HLF_ enums!
- * When changing this also adjust the default for 'highlight'. */
-#define HL_FLAGS { '8', '~', 'z', 'Z', '@', 'd', 'e', 'i', 'l', 'm', 'M', 'n', \
-                   'N', 'r', 's', 'S', 'c', 't', 'v', 'V', 'w', 'W', 'f', 'F', \
-                   'A', 'C', 'D', 'T', '-', '>', 'B', 'P', 'R', 'L', '+', '=', \
-                   'x', 'X', '*', '#', '_', '!', '.', 'o', 'q', '0', 'I' }
+EXTERN const char *hlf_names[] INIT(= {
+  [HLF_8] = "SpecialKey",
+  [HLF_EOB] = "EndOfBuffer",
+  [HLF_TERM] = "TermCursor",
+  [HLF_TERMNC] = "TermCursorNC",
+  [HLF_AT] = "NonText",
+  [HLF_D] = "Directory",
+  [HLF_E] = "ErrorMsg",
+  [HLF_I] = "IncSearch",
+  [HLF_L] = "Search",
+  [HLF_M] = "MoreMsg",
+  [HLF_CM] = "ModeMsg",
+  [HLF_N] = "LineNr",
+  [HLF_CLN] = "CursorLineNr",
+  [HLF_R] = "Question",
+  [HLF_S] = "StatusLine",
+  [HLF_SNC] = "StatusLineNC",
+  [HLF_C] = "VertSplit",
+  [HLF_T] = "Title",
+  [HLF_V] = "Visual",
+  [HLF_VNC] = "VisualNOS",
+  [HLF_W] = "WarningMsg",
+  [HLF_WM] = "WildMenu",
+  [HLF_FL] = "Folded",
+  [HLF_FC] = "FoldColumn",
+  [HLF_ADD] = "DiffAdd",
+  [HLF_CHD] = "DiffChange",
+  [HLF_DED] = "DiffDelete",
+  [HLF_TXD] = "DiffText",
+  [HLF_SC] = "SignColumn",
+  [HLF_CONCEAL] = "Conceal",
+  [HLF_SPB] = "SpellBad",
+  [HLF_SPC] = "SpellCap",
+  [HLF_SPR] = "SpellRare",
+  [HLF_SPL] = "SpellLocal",
+  [HLF_PNI] = "Pmenu",
+  [HLF_PSI] = "PmenuSel",
+  [HLF_PSB] = "PmenuSbar",
+  [HLF_PST] = "PmenuThumb",
+  [HLF_TP] = "TabLine",
+  [HLF_TPS] = "TabLineSel",
+  [HLF_TPF] = "TabLineFill",
+  [HLF_CUC] = "CursorColumn",
+  [HLF_CUL] = "CursorLine",
+  [HLF_MC] = "ColorColumn",
+  [HLF_QFL] = "QuickFixLine",
+  [HLF_0] = "Whitespace",
+  [HLF_INACTIVE] = "NormalNC",
+});
+
 
 EXTERN int highlight_attr[HLF_COUNT];       /* Highl. attr for each context. */
 EXTERN int highlight_user[9];                   /* User[1-9] attributes */
diff --git a/src/nvim/option.c b/src/nvim/option.c
index 9b4cd0924b..c36ca1bfe9 100644
--- a/src/nvim/option.c
+++ b/src/nvim/option.c
@@ -247,7 +247,7 @@ typedef struct vimoption {
   "8:SpecialKey,~:EndOfBuffer,z:TermCursor,Z:TermCursorNC,@:NonText," \
   "d:Directory,e:ErrorMsg,i:IncSearch,l:Search,m:MoreMsg,M:ModeMsg,n:LineNr," \
   "N:CursorLineNr,r:Question,s:StatusLine,S:StatusLineNC,c:VertSplit,t:Title," \
-  "v:Visual,w:WarningMsg,W:WildMenu,f:Folded,F:FoldColumn," \
+  "v:Visual,V:VisualNOS,w:WarningMsg,W:WildMenu,f:Folded,F:FoldColumn," \
   "A:DiffAdd,C:DiffChange,D:DiffDelete,T:DiffText,>:SignColumn,-:Conceal," \
   "B:SpellBad,P:SpellCap,R:SpellRare,L:SpellLocal,+:Pmenu,=:PmenuSel," \
   "x:PmenuSbar,X:PmenuThumb,*:TabLine,#:TabLineSel,_:TabLineFill," \
@@ -2124,7 +2124,7 @@ static void didset_options(void)
 static void didset_options2(void)
 {
   // Initialize the highlight_attr[] table.
-  (void)highlight_changed();
+  highlight_changed();
 
   // Parse default for 'clipboard'.
   (void)opt_strings_flags(p_cb, p_cb_values, &cb_flags, true);
@@ -2538,11 +2538,11 @@ did_set_string_option (
       if (s[2] == NUL)
         break;
     }
-  }
-  /* 'highlight' */
-  else if (varp == &p_hl) {
-    if (highlight_changed() == FAIL)
-      errmsg = e_invarg;        /* invalid flags */
+  } else if (varp == &p_hl) {
+    // 'highlight'
+    if (strcmp((char *)(*varp), HIGHLIGHT_INIT) != 0) {
+      errmsg = e_unsupportedoption;
+    }
   }
   /* 'nrformats' */
   else if (gvarp == &p_nf) {
@@ -2639,7 +2639,7 @@ did_set_string_option (
       if (varp == &p_enc) {
         // only encoding=utf-8 allowed
         if (STRCMP(p_enc, "utf-8") != 0) {
-          errmsg = e_invarg;
+          errmsg = e_unsupportedoption;
         }
       }
     }
@@ -3207,8 +3207,6 @@ did_set_string_option (
      */
     if (did_chartab)
       (void)init_chartab();
-    if (varp == &p_hl)
-      (void)highlight_changed();
   } else {
     /* Remember where the option was set. */
     set_option_scriptID_idx(opt_idx, opt_flags, current_SID);
@@ -4827,17 +4825,6 @@ char *set_option_value(const char *const name, const long number,
   return NULL;
 }
 
-char_u *get_highlight_default(void)
-{
-  int i;
-
-  i = findoption("hl");
-  if (i >= 0) {
-    return options[i].def_val[VI_DEFAULT];
-  }
-  return (char_u *)NULL;
-}
-
 /*
  * Translate a string like "t_xx", "<t_xx>" or "<S-Tab>" to a key number.
  */
diff --git a/src/nvim/syntax.c b/src/nvim/syntax.c
index ce48547163..a0725c5831 100644
--- a/src/nvim/syntax.c
+++ b/src/nvim/syntax.c
@@ -7304,110 +7304,34 @@ static void highlight_attr_set_all(void)
   }
 }
 
-/*
- * Translate the 'highlight' option into attributes in highlight_attr[] and
- * set up the user highlights User1..9. A set of
- * corresponding highlights to use on top of HLF_SNC is computed.
- * Called only when the 'highlight' option has been changed and upon first
- * screen redraw after any :highlight command.
- * Return FAIL when an invalid flag is found in 'highlight'.  OK otherwise.
- */
-int highlight_changed(void)
+/// Tranlate highlight groups into attributes in highlight_attr[] and set up
+/// the user highlights User1..9. A set of corresponding highlights to use on
+/// top of HLF_SNC is computed.  Called only when nvim starts and upon first
+/// screen redraw after any :highlight command.
+void highlight_changed(void)
 {
-  int hlf;
-  int i;
-  char_u      *p;
   int attr;
-  char_u      *end;
   int id;
   char_u userhl[10];
   int id_SNC = -1;
   int id_S = -1;
   int hlcnt;
-  static int hl_flags[HLF_COUNT] = HL_FLAGS;
 
   need_highlight_changed = FALSE;
 
-  /*
-   * Clear all attributes.
-   */
-  for (hlf = 0; hlf < (int)HLF_COUNT; ++hlf)
-    highlight_attr[hlf] = 0;
-
-  /*
-   * First set all attributes to their default value.
-   * Then use the attributes from the 'highlight' option.
-   */
-  for (i = 0; i < 2; ++i) {
-    if (i)
-      p = p_hl;
-    else
-      p = get_highlight_default();
-    if (p == NULL)          /* just in case */
-      continue;
-
-    while (*p) {
-      for (hlf = 0; hlf < (int)HLF_COUNT; ++hlf)
-        if (hl_flags[hlf] == *p)
-          break;
-      ++p;
-      if (hlf == (int)HLF_COUNT || *p == NUL)
-        return FAIL;
-
-      /*
-       * Allow several hl_flags to be combined, like "bu" for
-       * bold-underlined.
-       */
-      attr = 0;
-      bool colon = false;
-      for (; *p && *p != ','; ++p) {  // parse upto comma
-        if (ascii_iswhite(*p)) {  // ignore white space
-          continue;
-        }
-
-        if (colon)          /* Combination with ':' is not allowed. */
-          return FAIL;
-
-        switch (*p) {
-        case 'b':   attr |= HL_BOLD;
-          break;
-        case 'i':   attr |= HL_ITALIC;
-          break;
-        case '-':
-        case 'n':                                   /* no highlighting */
-          break;
-        case 'r':   attr |= HL_INVERSE;
-          break;
-        case 's':   attr |= HL_STANDOUT;
-          break;
-        case 'u':   attr |= HL_UNDERLINE;
-          break;
-        case 'c':   attr |= HL_UNDERCURL;
-          break;
-        case ':':   ++p;                            /* highlight group name */
-          if (attr || *p == NUL)                         /* no combinations */
-            return FAIL;
-          colon = true;
-          end = vim_strchr(p, ',');
-          if (end == NULL)
-            end = p + STRLEN(p);
-          id = syn_check_group(p, (int)(end - p));
-          if (id == 0)
-            return FAIL;
-          attr = syn_id2attr(id);
-          p = end - 1;
-          if (hlf == (int)HLF_SNC)
-            id_SNC = syn_get_final_id(id);
-          else if (hlf == (int)HLF_S)
-            id_S = syn_get_final_id(id);
-          break;
-        default:    return FAIL;
-        }
-      }
-      highlight_attr[hlf] = attr;
-
-      p = skip_to_option_part(p);           /* skip comma and spaces */
+  /// Translate builtin highlight groups into attributes for quick lookup.
+  for (int hlf = 0; hlf < (int)HLF_COUNT; hlf++) {
+    id = syn_check_group((char_u *)hlf_names[hlf], STRLEN(hlf_names[hlf]));
+    if (id == 0) {
+      abort();
+    }
+    attr = syn_id2attr(id);
+    if (hlf == (int)HLF_SNC) {
+      id_SNC = syn_get_final_id(id);
+    } else if (hlf == (int)HLF_S) {
+      id_S = syn_get_final_id(id);
     }
+    highlight_attr[hlf] = attr;
   }
 
   /* Setup the user highlights
@@ -7472,8 +7396,6 @@ int highlight_changed(void)
     }
   }
   highlight_ga.ga_len = hlcnt;
-
-  return OK;
 }