Merge bitcoin/bitcoin#32475: wallet: Use util::Error throughout AddWalletDescriptor instead of returning nullptr for some errors

785e1407b0 wallet: Use util::Error throughout AddWalletDescriptor (Ava Chow)

Pull request description:

  #32023 changed `AddWalletDescriptor` to return `util::Error`, but did not change all of the failure cases to do so. This may result in some callers continuing when there was actually an error. Unify all of the failure cases to use `util::Error` so that all callers handle `AddWalletDescriptor` errors in the same way.

  The encapsulated return type is changed from `ScriptPubKeyMan*` to `std::reference_wrapper<DescriptorScriptPubKeyMan>`. This avoids having a value that can be interpreted as a bool, and also removes the need to constantly dynamic_cast the returned value. The only kind of `ScriptPubKeyMan` that can come out of `AddWalletDescriptor` is a `DescriptorScriptPubKeyMan` anyways.

ACKs for top commit:
  Sjors:
    utACK 785e1407b0
  ryanofsky:
    Code review ACK 785e1407b0
  furszy:
    Code review ACK 785e1407b0

Tree-SHA512: 52a48263c8d4161a8c0419b7289c25b0986f8e3bcd10b639eeeb0b6862d08b6c5e70998d20070ab26b39ecd90ab83dc8b71c65d85f70626282cf8cc6abff50e7

src/wallet/test/fuzz/scriptpubkeyman.cpp

@@ -80,12 +80,9 @@ static std::optional<std::pair<WalletDescriptor, FlatSigningProvider>> CreateWal
 static DescriptorScriptPubKeyMan* CreateDescriptor(WalletDescriptor& wallet_desc, FlatSigningProvider& keys, CWallet& keystore)
 {
     LOCK(keystore.cs_wallet);
-    DescriptorScriptPubKeyMan* descriptor_spk_manager = nullptr;
-    auto spk_manager = *Assert(keystore.AddWalletDescriptor(wallet_desc, keys, /*label=*/"", /*internal=*/false));
-    if (spk_manager) {
-        descriptor_spk_manager = dynamic_cast<DescriptorScriptPubKeyMan*>(spk_manager);
-    }
-    return descriptor_spk_manager;
+    auto spk_manager_res = keystore.AddWalletDescriptor(wallet_desc, keys, /*label=*/"", /*internal=*/false);
+    if (!spk_manager_res) return nullptr;
+    return &spk_manager_res.value().get();
 };
 
 FUZZ_TARGET(scriptpubkeyman, .init = initialize_spkm)

src/wallet/test/psbt_wallet_tests.cpp

@@ -27,8 +27,7 @@ static void import_descriptor(CWallet& wallet, const std::string& descriptor)
     assert(descs.size() == 1);
     auto& desc = descs.at(0);
     WalletDescriptor w_desc(std::move(desc), 0, 0, 10, 0);
-    auto spk_manager = *Assert(wallet.AddWalletDescriptor(w_desc, provider, "", false));
-    assert(spk_manager);
+    Assert(wallet.AddWalletDescriptor(w_desc, provider, "", false));
 }
 
 BOOST_AUTO_TEST_CASE(psbt_updater_test)

src/wallet/test/scriptpubkeyman_tests.cpp

@@ -25,13 +25,13 @@ BOOST_AUTO_TEST_CASE(DescriptorScriptPubKeyManTests)
     // Verify that a SigningProvider for a pubkey is only returned if its corresponding private key is available
     auto key_internal = GenerateRandomKey();
     std::string desc_str = "tr(" + EncodeSecret(key_internal) + ",pk(" + HexStr(key_scriptpath.GetPubKey()) + "))";
-    auto spk_man1 = dynamic_cast<DescriptorScriptPubKeyMan*>(CreateDescriptor(keystore, desc_str, true));
+    auto spk_man1 = CreateDescriptor(keystore, desc_str, true);
     BOOST_CHECK(spk_man1 != nullptr);
     auto signprov_keypath_spendable = spk_man1->GetSigningProvider(key_internal.GetPubKey());
     BOOST_CHECK(signprov_keypath_spendable != nullptr);
 
     desc_str = "tr(" + HexStr(XOnlyPubKey::NUMS_H) + ",pk(" + HexStr(key_scriptpath.GetPubKey()) + "))";
-    auto spk_man2 = dynamic_cast<DescriptorScriptPubKeyMan*>(CreateDescriptor(keystore, desc_str, true));
+    auto spk_man2 = CreateDescriptor(keystore, desc_str, true);
     BOOST_CHECK(spk_man2 != nullptr);
     auto signprov_keypath_nums_h = spk_man2->GetSigningProvider(XOnlyPubKey::NUMS_H.GetEvenCorrespondingCPubKey());
     BOOST_CHECK(signprov_keypath_nums_h == nullptr);

src/wallet/test/util.cpp

@@ -35,8 +35,7 @@ std::unique_ptr<CWallet> CreateSyncedWallet(interfaces::Chain& chain, CChain& cc
         assert(descs.size() == 1);
         auto& desc = descs.at(0);
         WalletDescriptor w_desc(std::move(desc), 0, 0, 1, 1);
-        auto spk_manager = *Assert(wallet->AddWalletDescriptor(w_desc, provider, "", false));
-        assert(spk_manager);
+        Assert(wallet->AddWalletDescriptor(w_desc, provider, "", false));
     }
     WalletRescanReserver reserver(*wallet);
     reserver.reserve();
@@ -194,7 +193,7 @@ MockableDatabase& GetMockableDatabase(CWallet& wallet)
     return dynamic_cast<MockableDatabase&>(wallet.GetDatabase());
 }
 
-wallet::ScriptPubKeyMan* CreateDescriptor(CWallet& keystore, const std::string& desc_str, const bool success)
+wallet::DescriptorScriptPubKeyMan* CreateDescriptor(CWallet& keystore, const std::string& desc_str, const bool success)
 {
     keystore.SetWalletFlag(WALLET_FLAG_DESCRIPTORS);
 
@@ -211,6 +210,6 @@ wallet::ScriptPubKeyMan* CreateDescriptor(CWallet& keystore, const std::string&
 
     LOCK(keystore.cs_wallet);
     auto spkm = Assert(keystore.AddWalletDescriptor(w_desc, keys,/*label=*/"", /*internal=*/false));
-    return spkm.value();
+    return &spkm.value().get();
 };
 } // namespace wallet

src/wallet/test/util.h

@@ -116,7 +116,7 @@ public:
 std::unique_ptr<WalletDatabase> CreateMockableWalletDatabase(MockableData records = {});
 MockableDatabase& GetMockableDatabase(CWallet& wallet);
 
-ScriptPubKeyMan* CreateDescriptor(CWallet& keystore, const std::string& desc_str, const bool success);
+DescriptorScriptPubKeyMan* CreateDescriptor(CWallet& keystore, const std::string& desc_str, const bool success);
 } // namespace wallet
 
 #endif // BITCOIN_WALLET_TEST_UTIL_H

src/wallet/test/wallet_tests.cpp

@@ -66,8 +66,7 @@ static void AddKey(CWallet& wallet, const CKey& key)
     assert(descs.size() == 1);
     auto& desc = descs.at(0);
     WalletDescriptor w_desc(std::move(desc), 0, 0, 1, 1);
-    auto spk_manager = *Assert(wallet.AddWalletDescriptor(w_desc, provider, "", false));
-    assert(spk_manager);
+    Assert(wallet.AddWalletDescriptor(w_desc, provider, "", false));
 }
 
 BOOST_FIXTURE_TEST_CASE(update_non_range_descriptor, TestingSetup)