Always require tapleaf and taproot for TaprootSingleScriptSigInput

Author: MatthewLM

coinlib/lib/src/tx/inputs/taproot_single_script_sig_input.dart

@@ -14,21 +14,21 @@ import 'taproot_script_input.dart';
 /// An input that provides a single signature to satisfy a tapscript [leaf].
 class TaprootSingleScriptSigInput extends TaprootInput {
 
-  final TapLeafChecksig? leaf;
+  final TapLeafChecksig leaf;
   final SchnorrInputSignature? insig;
 
   TaprootSingleScriptSigInput._({
+    required this.leaf,
+    required Uint8List controlBlock,
+    required super.sequence,
     OutPoint? prevOut,
-    this.leaf,
-    Uint8List? controlBlock,
     this.insig,
-    required super.sequence,
   }) : super(
     prevOut: prevOut ?? OutPoint.nothing,
     witness: [
       if (insig != null) insig.bytes,
-      if (leaf != null) leaf.script.compiled,
-      if (controlBlock != null) controlBlock,
+      leaf.script.compiled,
+      controlBlock,
     ],
   );
 
@@ -48,13 +48,6 @@ class TaprootSingleScriptSigInput extends TaprootInput {
     sequence: sequence,
   );
 
-  /// Create an APO input with no information that can only be signed with
-  /// ANYPREVOUTANYSCRIPT.
-  TaprootSingleScriptSigInput.anyPrevOutAnyScript({
-    SchnorrInputSignature? insig,
-    int sequence = Input.sequenceFinal,
-  }) : this._(insig: insig, sequence: sequence);
-
   /// Create an APO input specifying a [Taproot] and [TapLeaf] that can be
   /// signed using ANYPREVOUT or ANYPREVOUTANYSCRIPT. ANYPREVOUTANYSCRIPT may
   /// also ommit the taproot information using [anyPrevOutAnyScript()].
@@ -103,23 +96,6 @@ class TaprootSingleScriptSigInput extends TaprootInput {
 
   }
 
-  /// Add the [Taproot] and [TapLeaf] required to complete the input for
-  /// ANYPREVOUTANYSCRIPT. The [prevOut] may optionally be added.
-  ///
-  /// The signature is not invalidated for ANYPREVOUTANYSCRIPT.
-  TaprootSingleScriptSigInput addTaproot({
-    required Taproot taproot,
-    required TapLeafChecksig leaf,
-    OutPoint? prevOut,
-  }) => TaprootSingleScriptSigInput._(
-    prevOut: prevOut ?? this.prevOut,
-    leaf: leaf,
-    controlBlock: taproot.controlBlockForLeaf(leaf),
-    insig: (insig != null && insig!.hashType.anyPrevOutAnyScript)
-      ? insig : null,
-    sequence: sequence,
-  );
-
   /// Complete the input by adding (or replacing) the [OutPoint].
   ///
   /// A signature is not invalidated if ANYPREVOUT or ANYPREVOUTANYSCRIPT is
@@ -129,7 +105,7 @@ class TaprootSingleScriptSigInput extends TaprootInput {
   ) => TaprootSingleScriptSigInput._(
     prevOut: prevOut,
     leaf: leaf,
-    controlBlock: leaf == null ? null : witness.last,
+    controlBlock: witness.last,
     insig: (insig != null && insig!.hashType.requiresApo) ? insig : null,
     sequence: sequence,
   );
@@ -140,7 +116,7 @@ class TaprootSingleScriptSigInput extends TaprootInput {
   ) => TaprootSingleScriptSigInput._(
     prevOut: prevOut,
     leaf: leaf,
-    controlBlock: leaf == null ? null : witness.last,
+    controlBlock: witness.last,
     insig: insig,
     sequence: sequence,
   );
@@ -151,17 +127,14 @@ class TaprootSingleScriptSigInput extends TaprootInput {
     required ECPrivateKey key,
   }) {
 
-    if (leaf != null && !leaf!.isApo && details.hashType.requiresApo) {
+    if (!leaf.isApo && details.hashType.requiresApo) {
       throw CannotSignInput(
         "Cannot sign with ${details.hashType} for non-APO key",
       );
     }
 
     return addSignature(
-      createInputSignature(
-        key: key,
-        details: leaf == null ? details : details.addLeafHash(leaf!.hash),
-      ),
+      createInputSignature(key: key, details: details.addLeafHash(leaf.hash)),
     );
 
   }

coinlib/test/tx/inputs/taproot_single_script_sig_input_test.dart

@@ -14,6 +14,10 @@ final apoTR = Taproot(
   internalKey: privkey.pubkey,
   mast: TapLeafChecksig.apoInternal,
 );
+final apoInput = TaprootSingleScriptSigInput.anyPrevOut(
+  taproot: apoTR,
+  leaf: TapLeafChecksig.apoInternal,
+);
 final unsignedTx = Transaction(
   inputs: [
     TaprootSingleScriptSigInput(
@@ -22,12 +26,8 @@ final unsignedTx = Transaction(
       leaf:regularLeaf,
       sequence: sequence,
     ),
-    TaprootSingleScriptSigInput.anyPrevOut(
-      taproot: apoTR,
-      leaf: TapLeafChecksig.apoInternal,
-      sequence: sequence,
-    ),
-    TaprootSingleScriptSigInput.anyPrevOutAnyScript(),
+    apoInput,
+    apoInput,
   ],
   outputs: [exampleOutput],
 );
@@ -44,7 +44,6 @@ void main() {
         int i, SigHashType hashType, {
           bool addPrevOutBeforeSign = false,
           bool addPrevOut = false,
-          bool addTaproot = false,
         }
       ) {
 
@@ -69,14 +68,6 @@ void main() {
         if (!addPrevOut) return;
 
         input = input.addPrevOut(examplePrevOut);
-        expect(input.complete, !addTaproot);
-
-        if (!addTaproot) return;
-
-        input = input.addTaproot(
-          taproot: apoTR,
-          leaf: TapLeafChecksig.apoInternal,
-        );
         expect(input.complete, true);
 
       }
@@ -91,89 +82,43 @@ void main() {
       expectSign(1, sigHashAOCP, addPrevOutBeforeSign: true);
 
       // APOAS
-      expectSign(2, sigHashAPOAS, addPrevOut: true, addTaproot: true);
+      expectSign(2, sigHashAPOAS, addPrevOut: true);
 
     });
 
-    test("signatures invalidate on new prevout or tapscript", () {
-
-      final altLeaf = TapLeafChecksig.apo(privkey.pubkey);
-
-      void expectComplete(
-        TaprootSingleScriptSigInput input,
-        bool onPrevOut,
-        bool onTaproot,
-      ) {
-        expect(input.complete, true);
-        expect(input.addPrevOut(exampleAltPrevOut).complete, onPrevOut);
-        expect(
-          input.addTaproot(
-            taproot: Taproot(internalKey: privkey.pubkey, mast: altLeaf),
-            leaf: altLeaf,
-          ).complete,
-          onTaproot,
-        );
-      }
-
-      expectComplete(
-        TaprootSingleScriptSigInput(
-          prevOut: examplePrevOut,
-          taproot: regularTR,
-          leaf: regularLeaf,
-          insig: schnorrInSig,
-        ),
-        false,
-        false,
-      );
+    test("signatures invalidate on new prevout", () {
 
-      expectComplete(
-        TaprootSingleScriptSigInput(
+      void expectComplete(SchnorrInputSignature inputSig, bool onPrevOut) {
+        final input = TaprootSingleScriptSigInput(
           prevOut: examplePrevOut,
           taproot: regularTR,
           leaf: regularLeaf,
-          insig: schnorrInSigAPO,
-        ),
-        true,
-        false,
-      );
-
-      expectComplete(
-        TaprootSingleScriptSigInput(
-          prevOut: examplePrevOut,
-          taproot: regularTR,
-          leaf: regularLeaf,
-          insig: schnorrInSigAPOAS,
-        ),
-        true,
-        true,
-      );
-
-    });
-
-    test(".sign() fail", () {
-
-      void expectFail(int i, SigHashType hashType) {
-        final input = unsignedTx.inputs[i] as TaprootSingleScriptSigInput;
-        expect(
-          () => input.sign(
-            details: TaprootScriptSignDetails(
-              tx: unsignedTx,
-              inputN: i,
-              prevOuts: [if (!hashType.anyPrevOutAnyScript) exampleOutput],
-              hashType: hashType,
-            ),
-            key: privkey,
-          ),
-          throwsA(isA<CannotSignInput>()),
+          insig: inputSig,
         );
+        expect(input.complete, true);
+        expect(input.addPrevOut(exampleAltPrevOut).complete, onPrevOut);
       }
 
-      // Signing APO for non-APO key
-      expectFail(0, sigHashAPO);
+      expectComplete(schnorrInSig, false);
+      expectComplete(schnorrInSigAPO, true);
+      expectComplete(schnorrInSigAPOAS, true);
 
-      // Missing leaf for non-APOAS
-      expectFail(2, sigHashAPO);
+    });
 
+    test(".sign() cannot sign APO for non-APO key", () {
+      final input = unsignedTx.inputs.first as TaprootSingleScriptSigInput;
+      expect(
+        () => input.sign(
+          details: TaprootScriptSignDetails(
+            tx: unsignedTx,
+            inputN: 0,
+            prevOuts: [exampleOutput],
+            hashType: sigHashAPO,
+          ),
+          key: privkey,
+        ),
+        throwsA(isA<CannotSignInput>()),
+      );
     });
 
     test(".match() success", () {

coinlib/test/tx/transaction_test.dart

@@ -918,6 +918,11 @@ void main() {
         mast: TapLeafChecksig.apoInternal,
       );
 
+      final apoInput = TaprootSingleScriptSigInput.anyPrevOut(
+        taproot: taprootApo,
+        leaf: leafApo,
+      );
+
       final tx = Transaction(
         inputs: [
           // Regular SIGHASH_ALL|ANYONECANPAY
@@ -930,12 +935,9 @@ void main() {
             leaf: leafRegular,
           ),
           // ANYPREVOUT
-          TaprootSingleScriptSigInput.anyPrevOut(
-            taproot: taprootApo,
-            leaf: leafApo,
-          ),
+          apoInput,
           // ANYPREVOUTANYSCRIPT
-          TaprootSingleScriptSigInput.anyPrevOutAnyScript(),
+          apoInput,
           // ANYPREVOUT, internal key
           TaprootSingleScriptSigInput.anyPrevOut(
             taproot: taprootApoInternal,
@@ -985,10 +987,8 @@ void main() {
         ),
         1,
       ).replaceInput(
-        (signedTx.inputs[2] as TaprootSingleScriptSigInput).addTaproot(
-          taproot: taprootApo,
-          leaf: leafApo,
-          prevOut: OutPoint.fromHex(
+        (signedTx.inputs[2] as TaprootSingleScriptSigInput).addPrevOut(
+          OutPoint.fromHex(
             "1bc7c900192ff96e2fbda841f102cf0e924f8614545b16ccf9a89b573d0258f5",
             1,
           ),