From 2968247d9c6772f3b46cc6b4accc24b61cb003a0 Mon Sep 17 00:00:00 2001
From: Matthew Slipper <me@matthewslipper.com>
Date: Tue, 7 Jan 2020 07:17:01 -0800
Subject: [PATCH] Merge PR #5479: Add convenience Incr() and Decr() methods to
 Uint

---
 types/uint.go      | 11 +++++++++++
 types/uint_test.go | 12 ++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/types/uint.go b/types/uint.go
index 1cc289b900..976b6414a9 100644
--- a/types/uint.go
+++ b/types/uint.go
@@ -107,6 +107,17 @@ func (u Uint) Mod(u2 Uint) Uint {
 	return Uint{mod(u.i, u2.i)}
 }
 
+// Incr increments the Uint by one.
+func (u Uint) Incr() Uint {
+	return u.Add(OneUint())
+}
+
+// Decr decrements the Uint by one.
+// Decr will panic if the Uint is zero.
+func (u Uint) Decr() Uint {
+	return u.Sub(OneUint())
+}
+
 // Quo divides Uint with uint64
 func (u Uint) QuoUint64(u2 uint64) Uint { return u.Quo(NewUint(u2)) }
 
diff --git a/types/uint_test.go b/types/uint_test.go
index e90fbf7f50..548dea5064 100644
--- a/types/uint_test.go
+++ b/types/uint_test.go
@@ -50,7 +50,9 @@ func TestUintPanics(t *testing.T) {
 	require.Panics(t, func() { ZeroUint().QuoUint64(0) })
 	require.Panics(t, func() { OneUint().Quo(ZeroUint().Sub(OneUint())) })
 	require.Panics(t, func() { uintmax.Add(OneUint()) })
+	require.Panics(t, func() { uintmax.Incr() })
 	require.Panics(t, func() { uintmin.Sub(OneUint()) })
+	require.Panics(t, func() { uintmin.Decr() })
 
 	require.Equal(t, uint64(0), MinUint(ZeroUint(), OneUint()).Uint64())
 	require.Equal(t, uint64(1), MaxUint(ZeroUint(), OneUint()).Uint64())
@@ -115,6 +117,7 @@ func TestArithUint(t *testing.T) {
 			{u1.QuoUint64(n2), n1 / n2},
 			{MinUint(u1, u2), minuint(n1, n2)},
 			{MaxUint(u1, u2), maxuint(n1, n2)},
+			{u1.Incr(), n1 + 1},
 		}
 
 		for tcnum, tc := range cases {
@@ -132,6 +135,7 @@ func TestArithUint(t *testing.T) {
 		}{
 			{u1.Sub(u2), n1 - n2},
 			{u1.SubUint64(n2), n1 - n2},
+			{u1.Decr(), n1 - 1},
 		}
 
 		for tcnum, tc := range subs {
@@ -183,6 +187,14 @@ func TestImmutabilityAllUint(t *testing.T) {
 		func(i *Uint) { _ = i.LT(randuint()) },
 		func(i *Uint) { _ = i.LTE(randuint()) },
 		func(i *Uint) { _ = i.String() },
+		func(i *Uint) { _ = i.Incr() },
+		func(i *Uint) {
+			if i.IsZero() {
+				return
+			}
+
+			_ = i.Decr()
+		},
 	}
 
 	for i := 0; i < 1000; i++ {