fix(printf): ignore 0 flag for integers if precision is specified

Fixes #27

Author: mpaland

printf.c

@@ -551,6 +551,11 @@ static int _vsnprintf(out_fct_type out, char* buffer, const size_t maxlen, const
           flags &= ~(FLAGS_PLUS | FLAGS_SPACE);
         }
 
+        // ignore '0' flag when precision is given
+        if (flags & FLAGS_PRECISION) {
+          flags &= ~FLAGS_ZEROPAD;
+        }
+
         // convert the integer
         if ((*format == 'i') || (*format == 'd')) {
           // signed

test/test_suite.cpp

@@ -934,6 +934,12 @@ TEST_CASE("length", "[]" ) {
 
   test::sprintf(buffer, "%20.X", 0U);
   REQUIRE(!strcmp(buffer, "                    "));
+
+  test::sprintf(buffer, "%02.0u", 0U);
+  REQUIRE(!strcmp(buffer, "  "));
+
+  test::sprintf(buffer, "%02.0d", 0);
+  REQUIRE(!strcmp(buffer, "  "));
 }