Add a way to clear local added fonts

Author: thomasp85

NAMESPACE

@@ -7,6 +7,7 @@ S3method(print,font_feature)
 export(add_fonts)
 export(as_font_weight)
 export(as_font_width)
+export(clear_local_fonts)
 export(clear_registry)
 export(font_fallback)
 export(font_feature)

R/cpp11.R

@@ -24,6 +24,10 @@ add_local_fonts <- function(paths) {
   .Call(`_systemfonts_add_local_fonts`, paths)
 }
 
+clear_local_fonts_c <- function() {
+  invisible(.Call(`_systemfonts_clear_local_fonts_c`))
+}
+
 match_font_c <- function(family, italic, bold) {
   .Call(`_systemfonts_match_font_c`, family, italic, bold)
 }

R/register_font.R

@@ -196,6 +196,8 @@ register_variant <- function(name, family, weight = NULL, width = NULL, features
 #'
 #' add_fonts(empty_font)
 #'
+#' clear_local_fonts()
+#'
 add_fonts <- function(files) {
   if (!is.character(files)) {
     stop("`files` must be a character vector")
@@ -219,3 +221,10 @@ scan_local_fonts <- function() {
   ))
   add_fonts(files)
 }
+#' @rdname add_fonts
+#' @export
+#'
+clear_local_fonts <- function() {
+  message("Run `scan_local_fonts()` in order to re-add the automatically added fonts")
+  clear_local_fonts_c()
+}

man/add_fonts.Rd

@@ -48,6 +48,14 @@ extern "C" SEXP _systemfonts_add_local_fonts(SEXP paths) {
     return cpp11::as_sexp(add_local_fonts(cpp11::as_cpp<cpp11::decay_t<cpp11::strings>>(paths)));
   END_CPP11
 }
+// font_local.h
+void clear_local_fonts_c();
+extern "C" SEXP _systemfonts_clear_local_fonts_c() {
+  BEGIN_CPP11
+    clear_local_fonts_c();
+    return R_NilValue;
+  END_CPP11
+}
 // font_matching.h
 cpp11::list match_font_c(cpp11::strings family, cpp11::logicals italic, cpp11::logicals bold);
 extern "C" SEXP _systemfonts_match_font_c(SEXP family, SEXP italic, SEXP bold) {
@@ -146,6 +154,7 @@ extern "C" SEXP _systemfonts_get_line_width_c(SEXP string, SEXP path, SEXP index
 extern "C" {
 static const R_CallMethodDef CallEntries[] = {
     {"_systemfonts_add_local_fonts",      (DL_FUNC) &_systemfonts_add_local_fonts,       1},
+    {"_systemfonts_clear_local_fonts_c",  (DL_FUNC) &_systemfonts_clear_local_fonts_c,   0},
     {"_systemfonts_clear_registry_c",     (DL_FUNC) &_systemfonts_clear_registry_c,      0},
     {"_systemfonts_dev_string_metrics_c", (DL_FUNC) &_systemfonts_dev_string_metrics_c,  6},
     {"_systemfonts_dev_string_widths_c",  (DL_FUNC) &_systemfonts_dev_string_widths_c,   6},

src/cpp11.cpp

@@ -83,5 +83,15 @@ int add_local_fonts(cpp11::strings paths) {
 
   FT_Done_FreeType(library);
 
+  FontMap& font_map = get_font_map();
+  font_map.clear();
+
   return 0;
 }
+
+void clear_local_fonts_c() {
+  ResultSet& font_list = get_local_font_list();
+  font_list.clear();
+  FontMap& font_map = get_font_map();
+  font_map.clear();
+}

src/font_local.cpp

@@ -11,3 +11,6 @@ FontDescriptor *match_local_fonts(FontDescriptor *desc);
 
 [[cpp11::register]]
 int add_local_fonts(cpp11::strings paths);
+
+[[cpp11::register]]
+void clear_local_fonts_c();