[librsvg: 36/53] Wrap the fontmap setting process in sync::Once

[Federico Mena Quintero <federico src gnome org>]

commit 188f216a5221776655c5d1c445861374179a9e30
Author: Federico Mena Quintero <federico gnome org>
Date:   Wed Oct 21 19:07:27 2020 -0500

    Wrap the fontmap setting process in sync::Once

 tests/src/utils.rs | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)
---
diff --git a/tests/src/utils.rs b/tests/src/utils.rs
index aa87be00..305fc7c8 100644
--- a/tests/src/utils.rs
+++ b/tests/src/utils.rs
@@ -4,6 +4,7 @@ use glib::translate::*;
 use libc;
 use std::env;
 use std::path::PathBuf;
+use std::sync::Once;
 
 #[cfg(have_pangoft2)]
 
@@ -72,7 +73,11 @@ mod pango_ft2 {
 
 #[cfg(have_pangoft2)]
 pub fn setup_font_map() {
-    unsafe { self::pango_ft2::load_test_fonts(); }
+    static ONCE: Once = Once::new();
+
+    ONCE.call_once(|| unsafe {
+        self::pango_ft2::load_test_fonts();
+    });
 }
 
 #[cfg(not(have_pangoft2))]