From b2cbc021898c863aa8cd28599d5af81f614e1413 Mon Sep 17 00:00:00 2001
From: fallenoak <git@fallenoak.me>
Date: Tue, 31 Jan 2023 22:07:33 -0600
Subject: [PATCH] feat(big): add SetOne

---
 storm/big/Ops.cpp |  5 +++++
 storm/big/Ops.hpp |  2 ++
 test/Big.cpp      | 18 ++++++++++++++++++
 3 files changed, 25 insertions(+)

diff --git a/storm/big/Ops.cpp b/storm/big/Ops.cpp
index f9e8fe6..4df9cb6 100644
--- a/storm/big/Ops.cpp
+++ b/storm/big/Ops.cpp
@@ -82,6 +82,11 @@ void Mul(BigBuffer& a, const BigBuffer& b, const BigBuffer& c, BigStack& stack)
     stack.UnmakeDistinct(a, aa);
 }
 
+void SetOne(BigBuffer& buffer) {
+    buffer.SetCount(1);
+    buffer[0] = 1;
+}
+
 void SetZero(BigBuffer& buffer) {
     buffer.Clear();
 }
diff --git a/storm/big/Ops.hpp b/storm/big/Ops.hpp
index b39353f..404c61b 100644
--- a/storm/big/Ops.hpp
+++ b/storm/big/Ops.hpp
@@ -21,6 +21,8 @@ void Mul(BigBuffer& a, const BigBuffer& b, uint64_t c);
 
 void Mul(BigBuffer& a, const BigBuffer& b, const BigBuffer& c, BigStack& stack);
 
+void SetOne(BigBuffer& buffer);
+
 void SetZero(BigBuffer& buffer);
 
 void ToBinary(TSGrowableArray<uint8_t>& output, const BigBuffer& buffer);
diff --git a/test/Big.cpp b/test/Big.cpp
index 4571c37..7afbbe0 100644
--- a/test/Big.cpp
+++ b/test/Big.cpp
@@ -421,6 +421,24 @@ TEST_CASE("SBigToBinaryBuffer", "[big]") {
     }
 }
 
+TEST_CASE("SetOne", "[big]") {
+    SECTION("sets buffer to one") {
+        BigData* num;
+        SBigNew(&num);
+        uint64_t data = 0x123456789ABCDEF0;
+        SBigFromBinary(num, reinterpret_cast<uint8_t*>(&data), sizeof(data));
+
+        CHECK(num->Primary().Count() == 2);
+
+        SetOne(num->Primary());
+
+        CHECK(num->Primary().Count() == 1);
+        CHECK(num->Primary()[0] == 1);
+
+        SBigDel(num);
+    }
+}
+
 TEST_CASE("SetZero", "[big]") {
     SECTION("sets buffer to zero") {
         BigData* num;