add ctors, some helpers

gnolang · Feb 26, 2024 · c1ea95d · c1ea95d
1 parent 6f4efc6
commit c1ea95d
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Showing 3 changed files with 198 additions and 28 deletions.
diff --git a/examples/gno.land/r/demo/tt/tt.gno b/examples/gno.land/r/demo/tt/tt.gno
@@ -0,0 +1,3 @@
+package tt
+
+func Render()
diff --git a/gnovm/stdlibs/std/coins.gno b/gnovm/stdlibs/std/coins.gno
@@ -1,6 +1,9 @@
 package std
 
-import "strconv"
+import (
+	"sort"
+	"strconv"
+)
 
 // NOTE: this is selectly copied over from pkgs/std/coin.go
 // TODO: import all functionality(?).
@@ -12,23 +15,62 @@ type Coin struct {
 	Amount int64  `json:"amount"`
 }
 
-func (c Coin) String() string {
-	return strconv.Itoa(int(c.Amount)) + c.Denom
+// NewCoin returns a new coin with a denomination and amount.
+func NewCoin(denom string, amount int64) Coin {
+	validate(amount)
+	1
+	return Coin{
+		Denom:  denom,
+		Amount: amount,
+	}
+}
+
+func (coin Coin) String() string {
+	return strconv.Itoa(int(coin.Amount)) + coin.Denom
+}
+
+func (coin Coin) IsGTE(other Coin) bool {
+	if coin.Denom != other.Denom {
+		panic("invalid coin denominations: " + coin.Denom)
+	}
+	return coin.Amount >= other.Amount
+}
+
+// IsZero returns if this represents no money
+func (coin Coin) IsZero() bool {
+	return coin.Amount == 0
 }
 
-func (c Coin) IsGTE(other Coin) bool {
-	if c.Denom != other.Denom {
-		panic("invalid coin denominations: " + c.Denom)
+// validate returns an error if the Coin has a negative amount
+func validate(amount int64) {
+	if amount < 0 {
+		panic("negative coin amount when constructing coin")
 	}
-	return c.Amount >= other.Amount
 }
 
 // Coins is a set of Coin, one per currency
 type Coins []Coin
 
-func (cz Coins) String() string {
+// NewCoins constructs a new coin set.
+func NewCoins(coins ...Coin) Coins {
+	// remove zeroes
+	newCoins := removeZeroCoins(Coins(coins))
+	if len(newCoins) == 0 {
+		return Coins{}
+	}
+
+	newCoins.Sort()
+
+	// detect duplicate Denoms
+	if dupIndex := findDup(newCoins); dupIndex != -1 {
+		panic("found duplicate denom when constructing coins set")
+	}
+	return newCoins
+}
+
+func (coins Coins) String() string {
 	res := ""
-	for i, c := range cz {
+	for i, c := range coins {
 		if i > 0 {
 			res += ","
 		}
@@ -37,18 +79,18 @@ func (cz Coins) String() string {
 	return res
 }
 
-func (cz Coins) AmountOf(denom string) int64 {
-	for _, c := range cz {
+func (coins Coins) AmountOf(denom string) int64 {
+	for _, c := range coins {
 		if c.Denom == denom {
 			return c.Amount
 		}
 	}
 	return 0
 }
 
-func (a Coins) Add(b Coins) Coins {
+func (coins Coins) Add(b Coins) Coins {
 	c := Coins{}
-	for _, ac := range a {
+	for _, ac := range coins {
 		bc := b.AmountOf(ac.Denom)
 		ac.Amount += bc
 		c = append(c, ac)
@@ -62,4 +104,50 @@ func (a Coins) Add(b Coins) Coins {
 	return c
 }
 
-// TODO implement Coin/Coins constructors.
+// removeZeroCoins removes all zero coins from the given coin set in-place.
+func removeZeroCoins(coins Coins) Coins {
+	i, l := 0, len(coins)
+	for i < l {
+		if coins[i].IsZero() {
+			// remove coin
+			coins = append(coins[:i], coins[i+1:]...)
+			l--
+		} else {
+			i++
+		}
+	}
+
+	return coins[:i]
+}
+
+// findDup works on the assumption that coins is sorted
+func findDup(coins Coins) int {
+	if len(coins) <= 1 {
+		return -1
+	}
+
+	prevDenom := coins[0].Denom
+	for i := 1; i < len(coins); i++ {
+		if coins[i].Denom == prevDenom {
+			return i
+		}
+		prevDenom = coins[i].Denom
+	}
+
+	return -1
+}
+
+// -----------------------------------------------------------------------------
+// Sort interface
+
+func (coins Coins) Len() int           { return len(coins) }
+func (coins Coins) Less(i, j int) bool { return coins[i].Denom < coins[j].Denom }
+func (coins Coins) Swap(i, j int)      { coins[i], coins[j] = coins[j], coins[i] }
+
+var _ sort.Interface = Coins{}
+
+// Sort is a helper function to sort the set of coins inplace
+func (coins Coins) Sort() Coins {
+	sort.Sort(coins)
+	return coins
+}
diff --git a/gnovm/stdlibs/stdshim/coins.gno b/gnovm/stdlibs/stdshim/coins.gno
@@ -1,6 +1,9 @@
 package std
 
-import "strconv"
+import (
+	"sort"
+	"strconv"
+)
 
 // NOTE: this is selectly copied over from pkgs/std/coin.go
 // TODO: import all functionality(?).
@@ -12,23 +15,53 @@ type Coin struct {
 	Amount int64  `json:"amount"`
 }
 
-func (c Coin) String() string {
-	return strconv.Itoa(int(c.Amount)) + c.Denom
+// NewCoin returns a new coin with a denomination and amount.
+func NewCoin(denom string, amount int64) Coin {
+	return Coin{
+		Denom:  denom,
+		Amount: amount,
+	}
+}
+
+func (coin Coin) String() string {
+	return strconv.Itoa(int(coin.Amount)) + coin.Denom
 }
 
-func (c Coin) IsGTE(other Coin) bool {
-	if c.Denom != other.Denom {
-		panic("invalid coin denominations: " + c.Denom)
+func (coin Coin) IsGTE(other Coin) bool {
+	if coin.Denom != other.Denom {
+		panic("invalid coin denominations: " + coin.Denom)
 	}
-	return c.Amount >= other.Amount
+	return coin.Amount >= other.Amount
+}
+
+// IsZero returns if this represents no money
+func (coin Coin) IsZero() bool {
+	return coin.Amount == 0
 }
 
 // Coins is a set of Coin, one per currency
 type Coins []Coin
 
-func (cz Coins) String() string {
+// NewCoins constructs a new coin set.
+func NewCoins(coins ...Coin) Coins {
+	// remove zeroes
+	newCoins := removeZeroCoins(Coins(coins))
+	if len(newCoins) == 0 {
+		return Coins{}
+	}
+
+	newCoins.Sort()
+
+	// detect duplicate Denoms
+	if dupIndex := findDup(newCoins); dupIndex != -1 {
+		panic("found duplicate denom when constructing coins set")
+	}
+	return newCoins
+}
+
+func (coins Coins) String() string {
 	res := ""
-	for i, c := range cz {
+	for i, c := range coins {
 		if i > 0 {
 			res += ","
 		}
@@ -37,18 +70,18 @@ func (cz Coins) String() string {
 	return res
 }
 
-func (cz Coins) AmountOf(denom string) int64 {
-	for _, c := range cz {
+func (coins Coins) AmountOf(denom string) int64 {
+	for _, c := range coins {
 		if c.Denom == denom {
 			return c.Amount
 		}
 	}
 	return 0
 }
 
-func (a Coins) Add(b Coins) Coins {
+func (coins Coins) Add(b Coins) Coins {
 	c := Coins{}
-	for _, ac := range a {
+	for _, ac := range coins {
 		bc := b.AmountOf(ac.Denom)
 		ac.Amount += bc
 		c = append(c, ac)
@@ -62,4 +95,50 @@ func (a Coins) Add(b Coins) Coins {
 	return c
 }
 
-// TODO implement Coin/Coins constructors.
+// removeZeroCoins removes all zero coins from the given coin set in-place.
+func removeZeroCoins(coins Coins) Coins {
+	i, l := 0, len(coins)
+	for i < l {
+		if coins[i].IsZero() {
+			// remove coin
+			coins = append(coins[:i], coins[i+1:]...)
+			l--
+		} else {
+			i++
+		}
+	}
+
+	return coins[:i]
+}
+
+// findDup works on the assumption that coins is sorted
+func findDup(coins Coins) int {
+	if len(coins) <= 1 {
+		return -1
+	}
+
+	prevDenom := coins[0].Denom
+	for i := 1; i < len(coins); i++ {
+		if coins[i].Denom == prevDenom {
+			return i
+		}
+		prevDenom = coins[i].Denom
+	}
+
+	return -1
+}
+
+// -----------------------------------------------------------------------------
+// Sort interface
+
+func (coins Coins) Len() int           { return len(coins) }
+func (coins Coins) Less(i, j int) bool { return coins[i].Denom < coins[j].Denom }
+func (coins Coins) Swap(i, j int)      { coins[i], coins[j] = coins[j], coins[i] }
+
+var _ sort.Interface = Coins{}
+
+// Sort is a helper function to sort the set of coins inplace
+func (coins Coins) Sort() Coins {
+	sort.Sort(coins)
+	return coins
+}