Chat: Add setting to control space after autocomplete

builtin/settingtypes.txt

@@ -961,6 +961,10 @@ chat_weblink_color (Weblink color) string #8888FF
 #    Value 0 will use the default font size.
 chat_font_size (Chat font size) int 0 0 72
 
+#    Append characters after autocompleting a player name.
+#    This is triggered by using the Tab key.
+#    The string must be surrounded with quotation marks (").
+chat_autocomplete_append (Autocomplete append string) string " "
 
 [**Content Repository]
 

src/chat.cpp

@@ -635,10 +635,21 @@ void ChatPrompt::nickCompletion(const std::set<std::string> &names)
 	}
 
 	if (completions.size() == 1) {
-		if (prefix.size() == line.size())
+		if (prefix.size() == line.size()) {
 			shortest.append(L": ");
-		else if (prefix_end == line.size())
-			shortest.append(L" ");
+		} else if (prefix_end == line.size()) {
+			bool is_valid = false;
+			auto what = trim(g_settings->get("chat_autocomplete_append"));
+			if (what.size() >= 2) {
+				if (what[0] == '"' && what[what.size() - 1] == '"') {
+					what.remove_prefix(1);
+					what.remove_suffix(1);
+					is_valid = true;
+				}
+			}
+
+			shortest.append(is_valid ? utf8_to_wide(what) : L" ");
+		}
 	}
 
 	makeLineRef().replace(prefix_start, prefix_end - prefix_start, shortest);

src/defaultsettings.cpp

@@ -129,6 +129,7 @@ void set_default_settings()
 	settings->setDefault("occlusion_culler", "bfs");
 	settings->setDefault("enable_raytraced_culling", "true");
 	settings->setDefault("chat_weblink_color", "#8888FF");
+	settings->setDefault("chat_autocomplete_append", "\" \"");
 
 	// Keymap
 	settings->setDefault("keymap_forward", "SYSTEM_SCANCODE_26|GAMEPAD_AXIS_MINUS_1"); // KEY_KEY_W|Left Joystick