feat(lsp)!: add rule-based sem token highlighting (#22022)

feat(lsp)!: change semantic token highlighting

Change the default highlights used, and add more highlights per token.

Add an LspTokenUpdate event and a highlight_token function.

:Inspect now shows any highlights applied by token highlighting rules,
default or user-defined.

BREAKING CHANGE: change the default highlight groups used by semantic
token highlighting.

2 files changed, 18 insertions, 10 deletions

diff --git a/src/nvim/auevents.lua b/src/nvim/auevents.lua
index a75ee3bbd5..aef08be820 100644
--- a/src/nvim/auevents.lua
+++ b/src/nvim/auevents.lua
@@ -72,6 +72,7 @@ return {
     'InsertLeavePre',         -- just before leaving Insert mode
     'LspAttach',              -- after an LSP client attaches to a buffer
     'LspDetach',              -- after an LSP client detaches from a buffer
+    'LspTokenUpdate',         -- after a visible LSP token is updated
     'MenuPopup',              -- just before popup menu is displayed
     'ModeChanged',            -- after changing the mode
     'OptionSet',              -- after setting any option
@@ -151,6 +152,7 @@ return {
     DiagnosticChanged=true,
     LspAttach=true,
     LspDetach=true,
+    LspTokenUpdate=true,
     RecordingEnter=true,
     RecordingLeave=true,
     Signal=true,
diff --git a/src/nvim/highlight_group.c b/src/nvim/highlight_group.c
index d2f5b60dc6..70ee6c757c 100644
--- a/src/nvim/highlight_group.c
+++ b/src/nvim/highlight_group.c
@@ -270,16 +270,22 @@ static const char *highlight_init_both[] = {
   "default link @tag Tag",
 
   // LSP semantic tokens
-  "default link @class Structure",
-  "default link @struct Structure",
-  "default link @enum Type",
-  "default link @enumMember Constant",
-  "default link @event Identifier",
-  "default link @interface Identifier",
-  "default link @modifier Identifier",
-  "default link @regexp SpecialChar",
-  "default link @typeParameter Type",
-  "default link @decorator Identifier",
+  "default link @lsp.type.class Structure",
+  "default link @lsp.type.decorator Function",
+  "default link @lsp.type.enum Structure",
+  "default link @lsp.type.enumMember Constant",
+  "default link @lsp.type.function Function",
+  "default link @lsp.type.interface Structure",
+  "default link @lsp.type.macro Macro",
+  "default link @lsp.type.method Function",
+  "default link @lsp.type.namespace Structure",
+  "default link @lsp.type.parameter Identifier",
+  "default link @lsp.type.property Identifier",
+  "default link @lsp.type.struct Structure",
+  "default link @lsp.type.type Type",
+  "default link @lsp.type.typeParameter TypeDef",
+  "default link @lsp.type.variable Identifier",
+
   NULL
 };