fix: RelativePow now returns 1 when 0^0 (#18211)

cosmos · Oct 23, 2023 · 442c3c5 · 442c3c5
1 parent 94a2164
commit 442c3c5
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Showing 3 changed files with 3 additions and 2 deletions.
diff --git a/math/CHANGELOG.md b/math/CHANGELOG.md
@@ -42,6 +42,7 @@ Ref: https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.j
 
 ### Bug Fixes
 
+* [#18211](https://github.com/cosmos/cosmos-sdk/pull/18211) RelativePow now returns 1 when 0^0, before it was returning the scale factor.
 * [#17725](https://github.com/cosmos/cosmos-sdk/pull/17725) Fix state break in ApproxRoot. This has been present since math/v1.0.1. It changed the rounding behavior at precision end in an intermediary division from banker's to truncation. The truncation occurs from binary right shift in the case of square roots. The change is now reverted back to banker's rounding universally for any root.
 
 ## [math/v1.1.2](https://github.com/cosmos/cosmos-sdk/releases/tag/math/v1.1.2) - 2023-08-21

diff --git a/math/uint.go b/math/uint.go
@@ -243,7 +243,7 @@ func checkNewUint(i *big.Int) (Uint, error) {
 func RelativePow(x, n, b Uint) (z Uint) {
 	if x.IsZero() {
 		if n.IsZero() {
-			z = b // 0^0 = 1
+			z = OneUint() // 0^0 = 1
 			return z
 		}
 		z = ZeroUint() // otherwise 0^a = 0

diff --git a/math/uint_test.go b/math/uint_test.go
@@ -271,7 +271,7 @@ func (s *uintTestSuite) TestRelativePow() {
 		want sdkmath.Uint
 	}{
 		{[]sdkmath.Uint{sdkmath.ZeroUint(), sdkmath.ZeroUint(), sdkmath.OneUint()}, sdkmath.OneUint()},
-		{[]sdkmath.Uint{sdkmath.ZeroUint(), sdkmath.ZeroUint(), sdkmath.NewUint(10)}, sdkmath.NewUint(10)},
+		{[]sdkmath.Uint{sdkmath.ZeroUint(), sdkmath.ZeroUint(), sdkmath.NewUint(10)}, sdkmath.NewUint(1)},
 		{[]sdkmath.Uint{sdkmath.ZeroUint(), sdkmath.OneUint(), sdkmath.NewUint(10)}, sdkmath.ZeroUint()},
 		{[]sdkmath.Uint{sdkmath.NewUint(10), sdkmath.NewUint(2), sdkmath.OneUint()}, sdkmath.NewUint(100)},
 		{[]sdkmath.Uint{sdkmath.NewUint(210), sdkmath.NewUint(2), sdkmath.NewUint(100)}, sdkmath.NewUint(441)},