Fix types/findDup()

.pending/bugfixes/sdk/4303-Fix-NewCoins-un

@@ -0,0 +1 @@
+#4303 Fix NewCoins() underlying function for duplicate coins detection.

types/coin.go

@@ -646,11 +646,12 @@ func findDup(coins Coins) int {
  return -1
  }
 
- prevDenom := coins[0]
+ prevDenom := coins[0].Denom
  for i := 1; i < len(coins); i++ {
- if coins[i] == prevDenom {
+ if coins[i].Denom == prevDenom {
  return i
  }
+ prevDenom = coins[i].Denom
  }
 
  return -1

types/coin_test.go

@@ -593,3 +593,31 @@ func TestCoinsIsAnyGT(t *testing.T) {
  require.False(t, Coins{twoBtc, twoAtom, threeEth}.IsAnyGT(Coins{fiveAtom, sixEth}))
  require.False(t, Coins{twoAtom, sixEth}.IsAnyGT(Coins{twoBtc, fiveAtom}))
 }
+
+func TestFindDup(t *testing.T) {
+ abc := NewInt64Coin("abc", 10)
+ def := NewInt64Coin("def", 10)
+ ghi := NewInt64Coin("ghi", 10)
+
+ type args struct {
+ coins Coins
+ }
+ tests := []struct {
+ name string
+ args args
+ want int
+ }{
+ {"empty", args{NewCoins()}, -1},
+ {"one coin", args{NewCoins(NewInt64Coin("xyz", 10))}, -1},
+ {"no dups", args{Coins{abc, def, ghi}}, -1},
+ {"dup at first position", args{Coins{abc, abc, def}}, 1},
+ {"dup after first position", args{Coins{abc, def, def}}, 2},
+ }
+ for _, tt := range tests {
+ t.Run(tt.name, func(t *testing.T) {
+ if got := findDup(tt.args.coins); got != tt.want {
+ t.Errorf("findDup() = %v, want %v", got, tt.want)
+ }
+ })
+ }
+}