remove Operand of null-aware operation warning

lib/src/certificate.dart

@@ -134,7 +134,7 @@ class TbsCertificate {
     if (elements.first.tag == 0xa0) {
       var e =
           ASN1Parser(elements.first.valueBytes()).nextObject() as ASN1Integer;
-      version = e.valueAsBigInteger!.toInt() + 1;
+      version = e.valueAsBigInteger.toInt() + 1;
       elements = elements.skip(1).toList();
     }
     var optionals = elements.skip(6);
@@ -151,7 +151,7 @@ class TbsCertificate {
             sUid = o.contentBytes();
             break;
           case 3:
-            ex = (ASN1Parser(o.contentBytes()!).nextObject() as ASN1Sequence)
+            ex = (ASN1Parser(o.contentBytes()).nextObject() as ASN1Sequence)
                 .elements
                 .map((v) => Extension.fromAsn1(v as ASN1Sequence))
                 .toList();
@@ -161,7 +161,7 @@ class TbsCertificate {
 
     return TbsCertificate(
         version: version,
-        serialNumber: (elements[0] as ASN1Integer).valueAsBigInteger!.toInt(),
+        serialNumber: (elements[0] as ASN1Integer).valueAsBigInteger.toInt(),
         signature: AlgorithmIdentifier.fromAsn1(elements[1] as ASN1Sequence),
         issuer: Name.fromAsn1(elements[2] as ASN1Sequence),
         validity: Validity.fromAsn1(elements[3] as ASN1Sequence),

lib/src/extension.dart

@@ -44,7 +44,7 @@ class Extension {
         extnId: id,
         isCritical: critical,
         extnValue: ExtensionValue.fromAsn1(
-            ASN1Parser(sequence.elements[octetIndex].contentBytes()!)
+            ASN1Parser(sequence.elements[octetIndex].contentBytes())
                 .nextObject(),
             id));
   }
@@ -352,7 +352,7 @@ class BasicConstraints extends ExtensionValue {
     int? len;
     for (var o in sequence.elements) {
       if (o is ASN1Boolean) {
-        cA = o.booleanValue!;
+        cA = o.booleanValue;
       }
       if (o is ASN1Integer) {
         len = o.intValue;

lib/src/util.dart

@@ -36,9 +36,9 @@ KeyPair ecKeyPairFromAsn1(ASN1Sequence sequence) {
     throw UnsupportedError('Only `ecPrivkeyVer1` supported.');
   }
 
-  var privateKey = toBigInt(sequence.elements[1].contentBytes()!);
+  var privateKey = toBigInt(sequence.elements[1].contentBytes());
 
-  var l = sequence.elements[1].contentBytes()!.length;
+  var l = sequence.elements[1].contentBytes().length;
 
   Identifier? curve;
 
@@ -52,7 +52,7 @@ KeyPair ecKeyPairFromAsn1(ASN1Sequence sequence) {
 
   EcPublicKey? publicKey;
   if (sequence.elements.length > i && sequence.elements[i].tag == 0xa1) {
-    var e = ASN1Parser(sequence.elements[i].contentBytes()!).nextObject()
+    var e = ASN1Parser(sequence.elements[i].contentBytes()).nextObject()
         as ASN1BitString;
     // https://tools.ietf.org/html/rfc5480#section-2.2
     // ECPoint ::= OCTET STRING
@@ -98,8 +98,8 @@ KeyPair rsaKeyPairFromAsn1(ASN1Sequence sequence) {
 }
 
 RsaPublicKey rsaPublicKeyFromAsn1(ASN1Sequence sequence) {
-  var modulus = (sequence.elements[0] as ASN1Integer).valueAsBigInteger!;
-  var exponent = (sequence.elements[1] as ASN1Integer).valueAsBigInteger!;
+  var modulus = (sequence.elements[0] as ASN1Integer).valueAsBigInteger;
+  var exponent = (sequence.elements[1] as ASN1Integer).valueAsBigInteger;
   return RsaPublicKey(modulus: modulus, exponent: exponent);
 }
 

lib/src/x509_base.dart

@@ -173,7 +173,7 @@ class PrivateKeyInfo {
         algorithm,
         keyPairFromAsn1(
             ASN1BitString(
-                (sequence.elements[2] as ASN1OctetString).contentBytes()!),
+                (sequence.elements[2] as ASN1OctetString).contentBytes()),
             algorithm.algorithm));
   }
 }
@@ -192,7 +192,7 @@ class EncryptedPrivateKeyInfo {
     final algorithm =
         AlgorithmIdentifier.fromAsn1(sequence.elements[0] as ASN1Sequence);
     return EncryptedPrivateKeyInfo(
-        algorithm, (sequence.elements[1] as ASN1OctetString).contentBytes()!);
+        algorithm, (sequence.elements[1] as ASN1OctetString).contentBytes());
   }
 }
 

pubspec.yaml

@@ -3,19 +3,19 @@ description: Dart library for parsing and working with X.509 certificates.
 version: 0.2.3
 homepage: https://github.com/appsup-dart/x509
 funding:
- - https://github.com/sponsors/rbellens
+  - https://github.com/sponsors/rbellens
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
+  sdk: ">=3.0.0 <4.0.0"
 
 dependencies:
   asn1lib: ^1.0.0
   quiver: ^3.0.0
-  crypto_keys: '>=0.2.0 <0.4.0'
+  crypto_keys: ">=0.2.0 <0.4.0"
 
 dev_dependencies:
   test: ^1.0.0
   lints: ^2.0.0
 
 false_secrets:
-  - test/files/*
+  - test/files/*