Handle end of input in scan

test/scan-test.cc

@@ -10,6 +10,7 @@
 #include <time.h>
 
 #include <climits>
+#include <thread>
 
 #include "fmt/os.h"
 #include "gmock/gmock.h"
@@ -123,6 +124,11 @@ TEST(scan_test, example) {
   EXPECT_EQ(value, 42);
 }
 
+TEST(scan_test, end_of_input) {
+  int value = 0;
+  fmt::scan("", "{}", value);
+}
+
 #if FMT_USE_FCNTL
 TEST(scan_test, file) {
   fmt::file read_end, write_end;