From 055648ea19897d38a9ee8a753acff149e98d53b6 Mon Sep 17 00:00:00 2001
From: voylin <voylinslife@gmail.com>
Date: Fri, 19 Dec 2025 16:05:38 +0900
Subject: [PATCH] Add highlight support for language server

Update modules/gdscript/language_server/gdscript_text_document.cpp

Co-authored-by: A Thousand Ships <96648715+AThousandShips@users.noreply.github.com>
---
 .../gdscript_language_protocol.cpp            |  1 +
 .../gdscript_text_document.cpp                | 19 +++++++++++++++
 .../language_server/gdscript_text_document.h  |  1 +
 modules/gdscript/language_server/godot_lsp.h  | 24 ++++++++++++++++++-
 4 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/modules/gdscript/language_server/gdscript_language_protocol.cpp b/modules/gdscript/language_server/gdscript_language_protocol.cpp
index 7662252c620..9e5080a8325 100644
--- a/modules/gdscript/language_server/gdscript_language_protocol.cpp
+++ b/modules/gdscript/language_server/gdscript_language_protocol.cpp
@@ -557,6 +557,7 @@ GDScriptLanguageProtocol::GDScriptLanguageProtocol() {
 	SET_DOCUMENT_METHOD(didSave);
 
 	SET_DOCUMENT_METHOD(documentSymbol);
+	SET_DOCUMENT_METHOD(documentHighlight);
 	SET_DOCUMENT_METHOD(completion);
 	SET_DOCUMENT_METHOD(rename);
 	SET_DOCUMENT_METHOD(prepareRename);
diff --git a/modules/gdscript/language_server/gdscript_text_document.cpp b/modules/gdscript/language_server/gdscript_text_document.cpp
index ad0ccb338f0..46b15fbaefa 100644
--- a/modules/gdscript/language_server/gdscript_text_document.cpp
+++ b/modules/gdscript/language_server/gdscript_text_document.cpp
@@ -165,6 +165,25 @@ Array GDScriptTextDocument::documentSymbol(const Dictionary &p_params) {
 	return arr;
 }
 
+Array GDScriptTextDocument::documentHighlight(const Dictionary &p_params) {
+	Array arr;
+	LSP::TextDocumentPositionParams params;
+	params.load(p_params);
+
+	const LSP::DocumentSymbol *symbol = GDScriptLanguageProtocol::get_singleton()->get_workspace()->resolve_symbol(params);
+	if (symbol) {
+		String path = GDScriptLanguageProtocol::get_singleton()->get_workspace()->get_file_path(params.textDocument.uri);
+		Vector<LSP::Location> usages = GDScriptLanguageProtocol::get_singleton()->get_workspace()->find_usages_in_file(*symbol, path);
+
+		for (const LSP::Location &usage : usages) {
+			LSP::DocumentHighlight highlight;
+			highlight.range = usage.range;
+			arr.push_back(highlight.to_json());
+		}
+	}
+	return arr;
+}
+
 Array GDScriptTextDocument::completion(const Dictionary &p_params) {
 	Array arr;
 
diff --git a/modules/gdscript/language_server/gdscript_text_document.h b/modules/gdscript/language_server/gdscript_text_document.h
index 86cd675bacd..54eecca64bb 100644
--- a/modules/gdscript/language_server/gdscript_text_document.h
+++ b/modules/gdscript/language_server/gdscript_text_document.h
@@ -62,6 +62,7 @@ public:
 
 	Variant nativeSymbol(const Dictionary &p_params);
 	Array documentSymbol(const Dictionary &p_params);
+	Array documentHighlight(const Dictionary &p_params);
 	Array completion(const Dictionary &p_params);
 	Dictionary resolve(const Dictionary &p_params);
 	Dictionary rename(const Dictionary &p_params);
diff --git a/modules/gdscript/language_server/godot_lsp.h b/modules/gdscript/language_server/godot_lsp.h
index 75470bfe782..31a5bdc1432 100644
--- a/modules/gdscript/language_server/godot_lsp.h
+++ b/modules/gdscript/language_server/godot_lsp.h
@@ -1761,7 +1761,7 @@ struct ServerCapabilities {
 	/**
 	 * The server provides document highlight support.
 	 */
-	bool documentHighlightProvider = false;
+	bool documentHighlightProvider = true;
 
 	/**
 	 * The server provides document symbol support.
@@ -2118,4 +2118,26 @@ static String marked_documentation(const String &p_bbcode) {
 	}
 	return markdown;
 }
+
+/**
+ * A document highlight is a range inside a text document which deserves
+ * special attention. Usually a document highlight is visualized by changing
+ * the background color of its range.
+ */
+struct DocumentHighlight {
+	/**
+	 * The range this highlight applies to.
+	 */
+	Range range;
+
+	_FORCE_INLINE_ Dictionary to_json() const {
+		Dictionary dict;
+		dict["range"] = range.to_json();
+		return dict;
+	}
+
+	_FORCE_INLINE_ void load(const Dictionary &p_params) {
+		range.load(p_params["range"]);
+	}
+};
 } // namespace LSP