Merge pull request #17589 from kchibisov/add-dashed-dotted-underline

Add support for double, dashed, and dotted underlines 

8 files changed, 80 insertions, 15 deletions

diff --git a/src/nvim/api/keysets.lua b/src/nvim/api/keysets.lua
index b05816f8ac..4676ec7596 100644
--- a/src/nvim/api/keysets.lua
+++ b/src/nvim/api/keysets.lua
@@ -83,7 +83,10 @@ return {
     "standout";
     "strikethrough";
     "underline";
+    "underlineline";
     "undercurl";
+    "underdot";
+    "underdash";
     "italic";
     "reverse";
     "nocombine";
@@ -105,7 +108,10 @@ return {
     "standout";
     "strikethrough";
     "underline";
+    "underlineline";
     "undercurl";
+    "underdot";
+    "underdash";
     "italic";
     "reverse";
     "nocombine";
diff --git a/src/nvim/eval/funcs.c b/src/nvim/eval/funcs.c
index fb2465b9fd..df1889b12d 100644
--- a/src/nvim/eval/funcs.c
+++ b/src/nvim/eval/funcs.c
@@ -11408,14 +11408,22 @@ static void f_synIDattr(typval_T *argvars, typval_T *rettv, FunPtr fptr)
       p = highlight_has_attr(id, HL_STANDOUT, modec);
     }
     break;
-  case 'u':
-    if (STRLEN(what) <= 5 || TOLOWER_ASC(what[5]) != 'c') {  // underline
-      p = highlight_has_attr(id, HL_UNDERLINE, modec);
-    } else {  // undercurl
+  case 'u': {
+    const size_t len = STRLEN(what);
+    if (len <= 5 || (TOLOWER_ASC(what[5]) == 'l' && len <= 9)) {  // underline
       p = highlight_has_attr(id, HL_UNDERCURL, modec);
+    } else if (TOLOWER_ASC(what[5]) == 'c') {  // undercurl
+       p = highlight_has_attr(id, HL_UNDERCURL, modec);
+    } else if (len > 9 && TOLOWER_ASC(what[9]) == 'l') {  // underlineline
+       p = highlight_has_attr(id, HL_UNDERLINELINE, modec);
+    } else if (len > 6 && TOLOWER_ASC(what[6]) == 'o') {  // underdot
+       p = highlight_has_attr(id, HL_UNDERDOT, modec);
+    } else {  // underdash
+       p = highlight_has_attr(id, HL_UNDERDASH, modec);
     }
     break;
   }
+  }
 
   rettv->v_type = VAR_STRING;
   rettv->vval.v_string = (char_u *)(p == NULL ? p : xstrdup(p));
diff --git a/src/nvim/hardcopy.c b/src/nvim/hardcopy.c
index eb10c65be9..93c8c53e33 100644
--- a/src/nvim/hardcopy.c
+++ b/src/nvim/hardcopy.c
@@ -420,7 +420,10 @@ static void prt_get_attr(int hl_id, prt_text_attr_T *pattr, int modec)
   pattr->bold = (highlight_has_attr(hl_id, HL_BOLD, modec) != NULL);
   pattr->italic = (highlight_has_attr(hl_id, HL_ITALIC, modec) != NULL);
   pattr->underline = (highlight_has_attr(hl_id, HL_UNDERLINE, modec) != NULL);
+  pattr->underlineline = (highlight_has_attr(hl_id, HL_UNDERLINELINE, modec) != NULL);
   pattr->undercurl = (highlight_has_attr(hl_id, HL_UNDERCURL, modec) != NULL);
+  pattr->underdot = (highlight_has_attr(hl_id, HL_UNDERDOT, modec) != NULL);
+  pattr->underdash = (highlight_has_attr(hl_id, HL_UNDERDASH, modec) != NULL);
 
   uint32_t fg_color = prt_get_color(hl_id, modec);
 
diff --git a/src/nvim/hardcopy.h b/src/nvim/hardcopy.h
index eba769d342..16119c5d2d 100644
--- a/src/nvim/hardcopy.h
+++ b/src/nvim/hardcopy.h
@@ -18,6 +18,9 @@ typedef struct {
   TriState italic;
   TriState underline;
   int undercurl;
+  int underlineline;
+  int underdot;
+  int underdash;
 } prt_text_attr_T;
 
 /*
diff --git a/src/nvim/highlight.c b/src/nvim/highlight.c
index e43a56086f..a01d8369ba 100644
--- a/src/nvim/highlight.c
+++ b/src/nvim/highlight.c
@@ -558,7 +558,7 @@ int hl_blend_attrs(int back_attr, int front_attr, bool *through)
     cattrs = battrs;
     cattrs.rgb_fg_color = rgb_blend(ratio, battrs.rgb_fg_color,
                                     fattrs.rgb_bg_color);
-    if (cattrs.rgb_ae_attr & (HL_UNDERLINE|HL_UNDERCURL)) {
+    if (cattrs.rgb_ae_attr & (HL_ANY_UNDERLINE)) {
       cattrs.rgb_sp_color = rgb_blend(ratio, battrs.rgb_sp_color,
                                       fattrs.rgb_bg_color);
     } else {
@@ -576,7 +576,7 @@ int hl_blend_attrs(int back_attr, int front_attr, bool *through)
     }
     cattrs.rgb_fg_color = rgb_blend(ratio/2, battrs.rgb_fg_color,
                                     fattrs.rgb_fg_color);
-    if (cattrs.rgb_ae_attr & (HL_UNDERLINE|HL_UNDERCURL)) {
+    if (cattrs.rgb_ae_attr & (HL_ANY_UNDERLINE)) {
       cattrs.rgb_sp_color = rgb_blend(ratio/2, battrs.rgb_bg_color,
                                       fattrs.rgb_sp_color);
     } else {
@@ -743,10 +743,23 @@ Dictionary hlattrs2dict(HlAttrs ae, bool use_rgb)
     PUT(hl, "underline", BOOLEAN_OBJ(true));
   }
 
+  if (mask & HL_UNDERLINELINE) {
+    PUT(hl, "underlineline", BOOLEAN_OBJ(true));
+  }
+
   if (mask & HL_UNDERCURL) {
     PUT(hl, "undercurl", BOOLEAN_OBJ(true));
   }
 
+  if (mask & HL_UNDERDOT) {
+    PUT(hl, "underdot", BOOLEAN_OBJ(true));
+  }
+
+  if (mask & HL_UNDERDASH) {
+    PUT(hl, "underdash", BOOLEAN_OBJ(true));
+  }
+
+
   if (mask & HL_ITALIC) {
     PUT(hl, "italic", BOOLEAN_OBJ(true));
   }
@@ -813,7 +826,10 @@ HlAttrs dict2hlattrs(Dict(highlight) *dict, bool use_rgb, int *link_id, Error *e
   CHECK_FLAG(dict, mask, bold, , HL_BOLD);
   CHECK_FLAG(dict, mask, standout, , HL_STANDOUT);
   CHECK_FLAG(dict, mask, underline, , HL_UNDERLINE);
+  CHECK_FLAG(dict, mask, underlineline, , HL_UNDERLINELINE);
   CHECK_FLAG(dict, mask, undercurl, , HL_UNDERCURL);
+  CHECK_FLAG(dict, mask, underdot, , HL_UNDERDOT);
+  CHECK_FLAG(dict, mask, underdash, , HL_UNDERDASH);
   CHECK_FLAG(dict, mask, italic, , HL_ITALIC);
   CHECK_FLAG(dict, mask, reverse, , HL_INVERSE);
   CHECK_FLAG(dict, mask, strikethrough, , HL_STRIKETHROUGH);
diff --git a/src/nvim/highlight_defs.h b/src/nvim/highlight_defs.h
index 50a03e0c02..dcfb9358bb 100644
--- a/src/nvim/highlight_defs.h
+++ b/src/nvim/highlight_defs.h
@@ -24,6 +24,10 @@ typedef enum {
   HL_FG_INDEXED    = 0x0200,
   HL_DEFAULT       = 0x0400,
   HL_GLOBAL        = 0x0800,
+  HL_UNDERLINELINE = 0x1000,
+  HL_UNDERDOT      = 0x2000,
+  HL_UNDERDASH     = 0x4000,
+  HL_ANY_UNDERLINE = HL_UNDERLINE | HL_UNDERLINELINE | HL_UNDERCURL | HL_UNDERDOT | HL_UNDERDASH,
 } HlAttrFlags;
 
 /// Stores a complete highlighting entry, including colors and attributes
diff --git a/src/nvim/syntax.c b/src/nvim/syntax.c
index 1e7801faee..54fce3d968 100644
--- a/src/nvim/syntax.c
+++ b/src/nvim/syntax.c
@@ -121,11 +121,11 @@ static int include_link = 0;    // when 2 include "nvim/link" and "clear"
 /// The "term", "cterm" and "gui" arguments can be any combination of the
 /// following names, separated by commas (but no spaces!).
 static char *(hl_name_table[]) =
-{ "bold", "standout", "underline", "undercurl",
-  "italic", "reverse", "inverse", "strikethrough", "nocombine", "NONE" };
+{ "bold", "standout", "underline", "underlineline", "undercurl", "underdot",
+  "underdash", "italic", "reverse", "inverse", "strikethrough", "nocombine", "NONE" };
 static int hl_attr_table[] =
-{ HL_BOLD, HL_STANDOUT, HL_UNDERLINE, HL_UNDERCURL, HL_ITALIC, HL_INVERSE,
-  HL_INVERSE, HL_STRIKETHROUGH, HL_NOCOMBINE, 0 };
+{ HL_BOLD, HL_STANDOUT, HL_UNDERLINE, HL_UNDERLINELINE, HL_UNDERCURL, HL_UNDERDOT, HL_UNDERDASH,
+  HL_ITALIC, HL_INVERSE, HL_INVERSE, HL_STRIKETHROUGH, HL_NOCOMBINE, 0 };
 
 static char e_illegal_arg[] = N_("E390: Illegal argument: %s");
 
diff --git a/src/nvim/tui/tui.c b/src/nvim/tui/tui.c
index 58061f020d..1ad82b7290 100644
--- a/src/nvim/tui/tui.c
+++ b/src/nvim/tui/tui.c
@@ -528,7 +528,7 @@ static bool attrs_differ(UI *ui, int id1, int id2, bool rgb)
     return a1.cterm_fg_color != a2.cterm_fg_color
            || a1.cterm_bg_color != a2.cterm_bg_color
            || a1.cterm_ae_attr != a2.cterm_ae_attr
-           || (a1.cterm_ae_attr & (HL_UNDERLINE|HL_UNDERCURL)
+           || (a1.cterm_ae_attr & HL_ANY_UNDERLINE
                && a1.rgb_sp_color != a2.rgb_sp_color);
   }
 }
@@ -552,15 +552,27 @@ static void update_attrs(UI *ui, int attr_id)
   bool strikethrough = attr & HL_STRIKETHROUGH;
 
   bool underline;
+  bool underlineline;
   bool undercurl;
+  bool underdot;
+  bool underdash;
   if (data->unibi_ext.set_underline_style != -1) {
     underline = attr & HL_UNDERLINE;
+    underlineline = attr & HL_UNDERLINELINE;
     undercurl = attr & HL_UNDERCURL;
+    underdash = attr & HL_UNDERDASH;
+    underdot = attr & HL_UNDERDOT;
   } else {
-    underline = (attr & HL_UNDERLINE) || (attr & HL_UNDERCURL);
+    underline = attr & HL_ANY_UNDERLINE;
+    underlineline = false;
     undercurl = false;
+    underdot = false;
+    underdash = false;
   }
 
+  bool has_any_underline = undercurl || underline
+                           || underdot || underdash || underlineline;
+
   if (unibi_get_str(data->ut, unibi_set_attributes)) {
     if (bold || reverse || underline || standout) {
       UNIBI_SET_NUM_VAR(data->params[0], standout);
@@ -599,11 +611,24 @@ static void update_attrs(UI *ui, int attr_id)
   if (strikethrough && data->unibi_ext.enter_strikethrough_mode != -1) {
     unibi_out_ext(ui, data->unibi_ext.enter_strikethrough_mode);
   }
+  if (underlineline && data->unibi_ext.set_underline_style != -1) {
+    UNIBI_SET_NUM_VAR(data->params[0], 2);
+    unibi_out_ext(ui, data->unibi_ext.set_underline_style);
+  }
   if (undercurl && data->unibi_ext.set_underline_style != -1) {
     UNIBI_SET_NUM_VAR(data->params[0], 3);
     unibi_out_ext(ui, data->unibi_ext.set_underline_style);
   }
-  if ((undercurl || underline) && data->unibi_ext.set_underline_color != -1) {
+  if (underdot && data->unibi_ext.set_underline_style != -1) {
+    UNIBI_SET_NUM_VAR(data->params[0], 4);
+    unibi_out_ext(ui, data->unibi_ext.set_underline_style);
+  }
+  if (underdash && data->unibi_ext.set_underline_style != -1) {
+    UNIBI_SET_NUM_VAR(data->params[0], 5);
+    unibi_out_ext(ui, data->unibi_ext.set_underline_style);
+  }
+
+  if (has_any_underline && data->unibi_ext.set_underline_color != -1) {
     int color = attrs.rgb_sp_color;
     if (color != -1) {
       UNIBI_SET_NUM_VAR(data->params[0], (color >> 16) & 0xff);  // red
@@ -652,13 +677,13 @@ static void update_attrs(UI *ui, int attr_id)
 
 
   data->default_attr = fg == -1 && bg == -1
-                       && !bold && !italic && !underline && !undercurl && !reverse && !standout
+                       && !bold && !italic && !has_any_underline && !reverse && !standout
                        && !strikethrough;
 
   // Non-BCE terminals can't clear with non-default background color. Some BCE
   // terminals don't support attributes either, so don't rely on it. But assume
   // italic and bold has no effect if there is no text.
-  data->can_clear_attr = !reverse && !standout && !underline && !undercurl
+  data->can_clear_attr = !reverse && !standout && !has_any_underline
                          && !strikethrough && (data->bce || bg == -1);
 }