From 8ce59d204de0644e5804547dce83fab9e95ec247 Mon Sep 17 00:00:00 2001
From: Alexander Entinger <consulting@lxrobotics.com>
Date: Mon, 4 Sep 2023 17:17:39 +0200
Subject: [PATCH 1/2] Add a test case demonstrating the issue when trying to
 print a zero value for uint64_t.

---
 test/src/Print/test_print.cpp | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/test/src/Print/test_print.cpp b/test/src/Print/test_print.cpp
index 92e9c083..ac731a89 100644
--- a/test/src/Print/test_print.cpp
+++ b/test/src/Print/test_print.cpp
@@ -110,12 +110,24 @@ TEST_CASE ("Print::print(unsigned long long, int = DEC|HEX|OCT|BIN)", "[Print-pr
 {
   PrintMock mock;
 
-  unsigned long long const val = 17;
+  GIVEN("a value of zero ...")
+  {
+    unsigned long long const val = 0;
 
-  WHEN("DEC") { mock.print(val, DEC); REQUIRE(mock._str  == "17"); }
-  WHEN("HEX") { mock.print(val, HEX); REQUIRE(mock._str  == "11"); }
-  WHEN("OCT") { mock.print(val, OCT); REQUIRE(mock._str  == "21"); }
-  WHEN("BIN") { mock.print(val, BIN); REQUIRE(mock._str  == "10001"); }
+    WHEN("DEC") { mock.print(val, DEC); REQUIRE(mock._str  == "0"); }
+    WHEN("HEX") { mock.print(val, HEX); REQUIRE(mock._str  == "0"); }
+    WHEN("OCT") { mock.print(val, OCT); REQUIRE(mock._str  == "0"); }
+    WHEN("BIN") { mock.print(val, BIN); REQUIRE(mock._str  == "0"); }
+  }
+  GIVEN("a non-zero value ...")
+  {
+    unsigned long long const val = 17;
+
+    WHEN("DEC") { mock.print(val, DEC); REQUIRE(mock._str  == "17"); }
+    WHEN("HEX") { mock.print(val, HEX); REQUIRE(mock._str  == "11"); }
+    WHEN("OCT") { mock.print(val, OCT); REQUIRE(mock._str  == "21"); }
+    WHEN("BIN") { mock.print(val, BIN); REQUIRE(mock._str  == "10001"); }
+  }
 }
 
 TEST_CASE ("Print::print(double, int = 2)", "[Print-print-10]")

From 754aa9b1a65f15c190d49b2478b95ccbe55b7f7a Mon Sep 17 00:00:00 2001
From: "Earle F. Philhower, III" <earlephilhower@yahoo.com>
Date: Sun, 3 Sep 2023 13:18:47 -0700
Subject: [PATCH 2/2] Fix Print::print(0ULL)

Fixes #1691

To be removed once upstream bug is fixed and core-api imported:
https://github.com/arduino/ArduinoCore-API/issues/178
---
 api/Print.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/api/Print.cpp b/api/Print.cpp
index 8c3e1930..f1e82469 100644
--- a/api/Print.cpp
+++ b/api/Print.cpp
@@ -287,6 +287,12 @@ size_t Print::printULLNumber(unsigned long long n64, uint8_t base)
   uint8_t i = 0;
   uint8_t innerLoops = 0;
 
+  // Special case workaround https://github.com/arduino/ArduinoCore-API/issues/178
+  if (n64 == 0) {
+    write('0');
+    return 1;
+  }
+
   // prevent crash if called with base == 1
   if (base < 2) base = 10;