feat: add simple address validity check

gnovm/stdlibs/std/crypto.gno

@@ -6,6 +6,11 @@ func (a Address) String() string {
 	return string(a)
 }
 
+// Valid checks if the address is of specific length. Doesn't check prefix or checksum for the address
+func (a Address) Valid() bool {
+	return len(a) == RawAddressSize*2 // hex length
+}
+
 const RawAddressSize = 20
 
 type RawAddress [RawAddressSize]byte

gnovm/stdlibs/std/crypto_test.gno

@@ -0,0 +1,30 @@
+package std
+
+import (
+	"testing"
+)
+
+func TestValid(t *testing.T) {
+	type test struct {
+		inputAddress Address
+		expected     bool
+	}
+
+	testCases := []test{
+		{inputAddress: "g1f4v282mwyhu29afke4vq5r2xzcm6z3ftnugcnv", expected: true},
+		{inputAddress: "g127jydsh6cms3lrtdenydxsckh23a8d6emqcvfa", expected: true},
+		{inputAddress: "g1u7y667z64x2h7vc6fmpcprgey4ck233jaww9zq", expected: true},
+		{inputAddress: "g14da4n9hcynyzz83q607uu8keuh9hwlv42ra6fa", expected: true},
+		{inputAddress: "", expected: false},
+		{inputAddress: "000000000000", expected: false},
+		{inputAddress: "0000000000000000000000000000000000000000000000000000000000000000000000", expected: false},
+	}
+
+	for _, tc := range testCases {
+		result := tc.inputAddress.Valid()
+
+		if result != tc.expected {
+			t.Fatalf("Expected: %t, got: %t", tc.expected, result)
+		}
+	}
+}