Backport: Removal of regex usage on denom validation

tests/integration/bank/keeper/deterministic_test.go

@@ -36,7 +36,7 @@ type DeterministicTestSuite struct {
 }
 
 var (
-	denomRegex   = sdk.DefaultCoinDenomRegex()
+	denomRegex   = `[a-zA-Z][a-zA-Z0-9/:._-]{2,127}`
 	addr1        = sdk.MustAccAddressFromBech32("cosmos139f7kncmglres2nf3h4hc4tade85ekfr8sulz5")
 	coin1        = sdk.NewCoin("denom", sdk.NewInt(10))
 	metadataAtom = banktypes.Metadata{

types/coin.go

@@ -6,6 +6,7 @@ import (
 	"regexp"
 	"sort"
 	"strings"
+	"unicode"
 )
 
 //-----------------------------------------------------------------------------
@@ -835,30 +836,15 @@ func (coins Coins) Sort() Coins {
 	return coins
 }
 
-//-----------------------------------------------------------------------------
-// Parsing
-
 var (
-	// Denominations can be 3 ~ 128 characters long and support letters, followed by either
-	// a letter, a number or a separator ('/', ':', '.', '_' or '-').
-	reDnmString = `[a-zA-Z][a-zA-Z0-9/:._-]{2,127}`
-	reDecAmt    = `[[:digit:]]+(?:\.[[:digit:]]+)?|\.[[:digit:]]+`
-	reSpc       = `[[:space:]]*`
-	reDnm       *regexp.Regexp
-	reDecCoin   *regexp.Regexp
-)
+	reDecAmt = `[[:digit:]]+(?:\.[[:digit:]]+)?|\.[[:digit:]]+`
+	reSpc    = `[[:space:]]*`
 
-func init() {
-	SetCoinDenomRegex(DefaultCoinDenomRegex)
-}
+	coinDenomRegex func() string
 
-// DefaultCoinDenomRegex returns the default regex string
-func DefaultCoinDenomRegex() string {
-	return reDnmString
-}
-
-// coinDenomRegex returns the current regex string and can be overwritten for custom validation
-var coinDenomRegex = DefaultCoinDenomRegex
+	reDnm     *regexp.Regexp
+	reDecCoin *regexp.Regexp
+)
 
 // SetCoinDenomRegex allows for coin's custom validation by overriding the regular
 // expression string used for denom validation.
@@ -871,12 +857,49 @@ func SetCoinDenomRegex(reFn func() string) {
 
 // ValidateDenom is the default validation function for Coin.Denom.
 func ValidateDenom(denom string) error {
-	if !reDnm.MatchString(denom) {
+	if reDnm == nil || reDecCoin == nil {
+		// Convert the string to a byte slice as required by the Ragel-generated function.
+
+		// Call the Ragel-generated function.
+		if !MatchDenom(denom) {
+			return fmt.Errorf("invalid denom: %s", denom)
+		}
+	} else if !reDnm.MatchString(denom) { // If reDnm has been initialized, use it for matching.
 		return fmt.Errorf("invalid denom: %s", denom)
 	}
+
 	return nil
 }
 
+// isValidRune checks if a given rune is a valid character for a rune.
+// It returns true if the rune is a letter, digit, '/', ':', '.', '_', or '-'.
+func isValidRune(r rune) bool {
+	return unicode.IsLetter(r) || unicode.IsDigit(r) || r == '/' || r == ':' || r == '.' || r == '_' || r == '-'
+}
+
+// MatchDenom checks if the given string is a valid denomination.
+// A valid denomination must have a length between 3 and 128 characters,
+// start with a letter, and only contain valid runes.
+func MatchDenom(s string) bool {
+	length := len(s)
+	if length < 3 || length > 128 {
+		return false
+	}
+
+	firstRune := rune(s[0])
+	if !unicode.IsLetter(firstRune) {
+		return false
+	}
+
+	for _, r := range s[1:] {
+		if !isValidRune(r) {
+			return false
+		}
+	}
+
+	return true
+}
+
 func mustValidateDenom(denom string) {
 	if err := ValidateDenom(denom); err != nil {
 		panic(err)

types/coin_test.go

@@ -112,6 +112,8 @@ func (s *coinTestSuite) TestCoinIsValid() {
 
 func (s *coinTestSuite) TestCustomValidation() {
 	newDnmRegex := `[\x{1F600}-\x{1F6FF}]`
+	reDnmString := `[a-zA-Z][a-zA-Z0-9/:._-]{2,127}`
+
 	sdk.SetCoinDenomRegex(func() string {
 		return newDnmRegex
 	})
@@ -130,7 +132,7 @@ func (s *coinTestSuite) TestCustomValidation() {
 	for i, tc := range cases {
 		s.Require().Equal(tc.expectPass, tc.coin.IsValid(), "unexpected result for IsValid, tc #%d", i)
 	}
-	sdk.SetCoinDenomRegex(sdk.DefaultCoinDenomRegex)
+	sdk.SetCoinDenomRegex(func() string { return reDnmString })
 }
 
 func (s *coinTestSuite) TestCoinsDenoms() {
@@ -998,6 +1000,33 @@ func (s *coinTestSuite) TestParseCoins() {
 	}
 }
 
+func (s *coinTestSuite) TestValidateDenom() {
+	cases := []struct {
+		input string
+		valid bool
+	}{
+		{"", false},
+		{"stake", true},
+		{"stake,", false},
+		{"me coin", false},
+		{"me coin much", false},
+		{"not a coin", false},
+		{"foo:bar", true}, // special characters '/' | ':' | '.' | '_' | '-' are allowed
+		{"atom10", true},  // number in denom is allowed
+		{"transfer/channelToA/uatom", true},
+		{"ibc/7F1D3FCF4AE79E1554D670D1AD949A9BA4E4A3C76C63093E17E446A46061A7A2", true},
+	}
+
+	for _, tc := range cases {
+		err := sdk.ValidateDenom(tc.input)
+		if !tc.valid {
+			s.Require().Error(err)
+		} else {
+			s.Require().NoError(err)
+		}
+	}
+}
+
 func (s *coinTestSuite) TestSortCoins() {
 	good := sdk.Coins{
 		sdk.NewInt64Coin("gas", 1),

types/dec_coin.go

@@ -4,6 +4,7 @@
 	"fmt"
 	"sort"
 	"strings"
+	"unicode"
 
 	"github.com/pkg/errors"
 )
@@ -621,14 +622,23 @@
 // ParseDecCoin parses a decimal coin from a string, returning an error if
 // invalid. An empty string is considered invalid.
 func ParseDecCoin(coinStr string) (coin DecCoin, err error) {
-	coinStr = strings.TrimSpace(coinStr)
+	var amountStr, denomStr string
+	// if custom parsing has not been set, use default coin regex
+	if reDecCoin == nil {
+		amountStr, denomStr, err = ParseDecAmount(coinStr)
+		if err != nil {
+			return DecCoin{}, err
+		}
+	} else {
+		coinStr = strings.TrimSpace(coinStr)
 
-	matches := reDecCoin.FindStringSubmatch(coinStr)
-	if matches == nil {
-		return DecCoin{}, fmt.Errorf("invalid decimal coin expression: %s", coinStr)
-	}
+		matches := reDecCoin.FindStringSubmatch(coinStr)
+		if matches == nil {
+			return DecCoin{}, fmt.Errorf("invalid decimal coin expression: %s", coinStr)
+		}
 
-	amountStr, denomStr := matches[1], matches[2]
+		amountStr, denomStr = matches[1], matches[2]
+	}
 
 	amount, err := NewDecFromStr(amountStr)
 	if err != nil {
@@ -642,6 +652,50 @@
 	return NewDecCoinFromDec(denomStr, amount), nil
 }
 
+// ParseDecAmount parses the given string into amount, denomination.
+func ParseDecAmount(coinStr string) (string, string, error) {
+	var amountRune, denomRune []rune
+
+	// Indicates the start of denom parsing
+	seenLetter := false
+	// Indicates we're currently parsing the amount
+	parsingAmount := true
+
+	for _, r := range strings.TrimSpace(coinStr) {
+		if parsingAmount {
+			if unicode.IsDigit(r) || r == '.' {
+				amountRune = append(amountRune, r)
+			} else if unicode.IsSpace(r) { // if space is seen, indicates that we have finished parsing amount
+				parsingAmount = false
+			} else if unicode.IsLetter(r) { // if letter is seen, indicates that it is the start of denom
+				parsingAmount = false
+				seenLetter = true
+				denomRune = append(denomRune, r)
+			} else { // Invalid character encountered in amount part
+				return "", "", fmt.Errorf("invalid character in coin string: %s", string(r))
+			}
+		} else if !seenLetter { // This logic flow is for skipping spaces between amount and denomination
+			if unicode.IsLetter(r) {
+				seenLetter = true
+				denomRune = append(denomRune, r)
+			} else if !unicode.IsSpace(r) {
+				// Invalid character before denomination starts
+				return "", "", fmt.Errorf("invalid start of denomination: %s", string(r))
+			}
+		} else {
+			// Parsing the denomination
+			if unicode.IsLetter(r) || unicode.IsDigit(r) || r == '/' || r == ':' || r == '.' || r == '_' || r == '-' {
+				denomRune = append(denomRune, r)
+			} else {
+				// Invalid character encountered in denomination part
+				return "", "", fmt.Errorf("invalid character in denomination: %s", string(r))
+			}
+		}
+	}
+
+	return string(amountRune), string(denomRune), nil
+}
+
 // ParseDecCoins will parse out a list of decimal coins separated by commas. If the parsing is successuful,
 // the provided coins will be sanitized by removing zero coins and sorting the coin set. Lastly
 // a validation of the coin set is executed. If the check passes, ParseDecCoins will return the sanitized coins.