types: update coin regex

CHANGELOG.md

@@ -282,6 +282,10 @@ Buffers for state serialization instead of Amino.
 
 ### Improvements
 
+* (types) [\#7027](https://github.com/cosmos/cosmos-sdk/pull/7027) `Coin(s)` and `DecCoin(s)` updates:
+  * Bump denomination max length to 128
+  * Allow unicode letters and numbers in denominations
+  * Added `Validate` function that returns a descriptive error
 * (baseapp) [\#6186](https://github.com/cosmos/cosmos-sdk/issues/6186) Support emitting events during `AnteHandler` execution.
 * (x/auth) [\#5702](https://github.com/cosmos/cosmos-sdk/pull/5702) Add parameter querying support for `x/auth`.
 * (types) [\#5581](https://github.com/cosmos/cosmos-sdk/pull/5581) Add convenience functions {,Must}Bech32ifyAddressBytes.

types/coin.go

@@ -12,16 +12,18 @@ import (
 // Coin
 
 // NewCoin returns a new coin with a denomination and amount. It will panic if
-// the amount is negative.
+// the amount is negative or if the denomination is invalid.
 func NewCoin(denom string, amount Int) Coin {
-	if err := validate(denom, amount); err != nil {
-		panic(err)
-	}
-
-	return Coin{
+	coin := Coin{
 		Denom:  denom,
 		Amount: amount,
 	}
+
+	if err := coin.Validate(); err != nil {
+		panic(err)
+	}
+
+	return coin
 }
 
 // NewInt64Coin returns a new coin with a denomination and amount. It will panic
@@ -35,26 +37,23 @@ func (coin Coin) String() string {
 	return fmt.Sprintf("%v%v", coin.Amount, coin.Denom)
 }
 
-// validate returns an error if the Coin has a negative amount or if
+// Validate returns an error if the Coin has a negative amount or if
 // the denom is invalid.
-func validate(denom string, amount Int) error {
-	if err := ValidateDenom(denom); err != nil {
+func (coin Coin) Validate() error {
+	if err := ValidateDenom(coin.Denom); err != nil {
 		return err
 	}
 
-	if amount.IsNegative() {
-		return fmt.Errorf("negative coin amount: %v", amount)
+	if coin.Amount.IsNegative() {
+		return fmt.Errorf("negative coin amount: %v", coin.Amount)
 	}
 
 	return nil
 }
 
-// IsValid returns true if the Coin has a non-negative amount and the denom is vaild.
+// IsValid returns true if the Coin has a non-negative amount and the denom is valid.
 func (coin Coin) IsValid() bool {
-	if err := validate(coin.Denom, coin.Amount); err != nil {
-		return false
-	}
-	return true
+	return coin.Validate() == nil
 }
 
 // IsZero returns if this represents no money
@@ -91,7 +90,7 @@ func (coin Coin) IsEqual(other Coin) bool {
 	return coin.Amount.Equal(other.Amount)
 }
 
-// Adds amounts of two coins with same denom. If the coins differ in denom then
+// Add adds amounts of two coins with same denom. If the coins differ in denom then
 // it panics.
 func (coin Coin) Add(coinB Coin) Coin {
 	if coin.Denom != coinB.Denom {
@@ -101,7 +100,7 @@ func (coin Coin) Add(coinB Coin) Coin {
 	return Coin{coin.Denom, coin.Amount.Add(coinB.Amount)}
 }
 
-// Subtracts amounts of two coins with same denom. If the coins differ in denom
+// Sub subtracts amounts of two coins with same denom. If the coins differ in denom
 // then it panics.
 func (coin Coin) Sub(coinB Coin) Coin {
 	if coin.Denom != coinB.Denom {
@@ -146,13 +145,8 @@ func NewCoins(coins ...Coin) Coins {
 
 	newCoins.Sort()
 
-	// detect duplicate Denoms
-	if dupIndex := findDup(newCoins); dupIndex != -1 {
-		panic(fmt.Errorf("find duplicate denom: %s", newCoins[dupIndex]))
-	}
-
-	if !newCoins.IsValid() {
-		panic(fmt.Errorf("invalid coin set: %s", newCoins))
+	if err := newCoins.Validate(); err != nil {
+		panic(fmt.Errorf("invalid coin set %s: %w", newCoins, err))
 	}
 
 	return newCoins
@@ -182,43 +176,61 @@ func (coins Coins) String() string {
 	return out[:len(out)-1]
 }
 
-// IsValid asserts the Coins are sorted, have positive amount,
-// and Denom does not contain upper case characters.
-func (coins Coins) IsValid() bool {
+// Validate checks that the Coins are sorted, have positive amount, with a valid and unique
+// denomination (i.e no duplicates). Otherwise, it returns an error.
+func (coins Coins) Validate() error {
 	switch len(coins) {
 	case 0:
-		return true
+		return nil
+
 	case 1:
 		if err := ValidateDenom(coins[0].Denom); err != nil {
-			return false
+			return err
 		}
-		return coins[0].IsPositive()
+		if !coins[0].IsPositive() {
+			return fmt.Errorf("coin %s amount is not positive", coins[0])
+		}
+		return nil
+
 	default:
 		// check single coin case
-		if !(Coins{coins[0]}).IsValid() {
-			return false
+		if err := (Coins{coins[0]}).Validate(); err != nil {
+			return err
 		}
 
 		lowDenom := coins[0].Denom
+		seenDenoms := make(map[string]bool)
+		seenDenoms[lowDenom] = true
+
 		for _, coin := range coins[1:] {
-			if strings.ToLower(coin.Denom) != coin.Denom {
-				return false
+			if seenDenoms[coin.Denom] {
+				return fmt.Errorf("duplicate denomination %s", coin.Denom)
+			}
+			if err := ValidateDenom(coin.Denom); err != nil {
+				return err
 			}
 			if coin.Denom <= lowDenom {
-				return false
+				return fmt.Errorf("denomination %s is not sorted", coin.Denom)
 			}
 			if !coin.IsPositive() {
-				return false
+				return fmt.Errorf("coin %s amount is not positive", coin.Denom)
 			}
 
 			// we compare each coin against the last denom
 			lowDenom = coin.Denom
+			seenDenoms[coin.Denom] = true
 		}
 
-		return true
+		return nil
 	}
 }
 
+// IsValid calls Validate and returns true when the Coins are sorted, have positive amount, with a
+// valid and unique denomination (i.e no duplicates).
+func (coins Coins) IsValid() bool {
+	return coins.Validate() == nil
+}
+
 // Add adds two sets of coins.
 //
 // e.g.
@@ -463,7 +475,7 @@ func (coins Coins) Empty() bool {
 	return len(coins) == 0
 }
 
-// Returns the amount of a denom from coins
+// AmountOf returns the amount of a denom from coins
 func (coins Coins) AmountOf(denom string) Int {
 	mustValidateDenom(denom)
 
@@ -560,13 +572,18 @@ func removeZeroCoins(coins Coins) Coins {
 //-----------------------------------------------------------------------------
 // Sort interface
 
-func (coins Coins) Len() int           { return len(coins) }
+// Len implements sort.Interface for Coins
+func (coins Coins) Len() int { return len(coins) }
+
+// Less implements sort.Interface for 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] }
+
+// Swap implements sort.Interface for Coins
+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
+// Sort is a helper function to sort the set of coins in-place
 func (coins Coins) Sort() Coins {
 	sort.Sort(coins)
 	return coins
@@ -576,8 +593,9 @@ func (coins Coins) Sort() Coins {
 // Parsing
 
 var (
-	// Denominations can be 3 ~ 64 characters long.
-	reDnmString = `[a-z][a-z0-9/]{2,63}`
+	// Denominations can be 3 ~ 128 characters long and support letters, followed by either
+	// a letter, a number or a separator ('/').
+	reDnmString = `[a-zA-Z][a-zA-Z0-9/]{2,127}`
 	reAmt       = `[[:digit:]]+`
 	reDecAmt    = `[[:digit:]]*\.[[:digit:]]+`
 	reSpc       = `[[:space:]]*`
@@ -619,15 +637,14 @@ func ParseCoin(coinStr string) (coin Coin, err error) {
 	}
 
 	if err := ValidateDenom(denomStr); err != nil {
-		return Coin{}, fmt.Errorf("invalid denom cannot contain upper case characters or spaces: %s", err)
+		return Coin{}, err
 	}
 
 	return NewCoin(denomStr, amount), nil
 }
 
-// ParseCoins will parse out a list of coins separated by commas.
-// If nothing is provided, it returns nil Coins.
-// Returned coins are sorted.
+// ParseCoins will parse out a list of coins separated by commas. If nothing is provided, it returns
+// nil Coins. If the coins aren't valid they return an error. Returned coins are sorted.
 func ParseCoins(coinsStr string) (Coins, error) {
 	coinsStr = strings.TrimSpace(coinsStr)
 	if len(coinsStr) == 0 {
@@ -649,31 +666,9 @@ func ParseCoins(coinsStr string) (Coins, error) {
 	coins.Sort()
 
 	// validate coins before returning
-	if !coins.IsValid() {
-		return nil, fmt.Errorf("parseCoins invalid: %#v", coins)
+	if err := coins.Validate(); err != nil {
+		return nil, err
 	}
 
 	return coins, nil
 }
-
-type findDupDescriptor interface {
-	GetDenomByIndex(int) string
-	Len() int
-}
-
-// findDup works on the assumption that coins is sorted
-func findDup(coins findDupDescriptor) int {
-	if coins.Len() <= 1 {
-		return -1
-	}
-
-	prevDenom := coins.GetDenomByIndex(0)
-	for i := 1; i < coins.Len(); i++ {
-		if coins.GetDenomByIndex(i) == prevDenom {
-			return i
-		}
-		prevDenom = coins.GetDenomByIndex(i)
-	}
-
-	return -1
-}