Merge #386: Remove the DescriptorTrait

32a74af Delete the DescriptorTrait (Tobin C. Harding)
52a480d Remove script_code from DescriptorTrait (Tobin C. Harding)
c6884fc Remove explicit_script from DescriptorTrait (Tobin C. Harding)
67d7c0e Remove unsigned_script_sig from DescriptorTrait (Tobin C. Harding)
e08f833 Remove script_pubkey from DescriptorTrait (Tobin C. Harding)
3d0b112 Remove address from DescriptorTrait (Tobin C. Harding)
4a9e20f Remove sanity_check from DescriptorTrait (Tobin C. Harding)
4980604 Delete the pretaproot module (Tobin C. Harding)
03d4bd6 Remove unnecessary path (Tobin C. Harding)

Pull request description:

  We never abstract over the `DescriptorTrait` so it is questionable if it should exist at all. Removing the `DescriptorTrait` allows us to also delete the `pretaproot` module because all the fallible vs infallible issues disolve.

  Delete the `DescriptorTrait`, implement the trait methods directly on `Descriptor` (fallible methods). Implement infallible versions of the trait methods on each descriptor as required.

  Done as individual patches to ease review. Although the work is only really meaningful as a block each patch is discreet enough to merge as is.

ACKs for top commit:
  apoelstra:
    ACK 32a74af
  thomaseizinger:
    ACK 32a74af
  sanket1729:
    ACK 32a74af. This is a very good improvement.

Tree-SHA512: 7043e11e995ac7d755c1c3014aa31d593961d0fae54cd82e84dfaa93767003291265d3c0e7543a70e56c07f6d2ca64830e285ebbba45c524e604d9acc71017fc

Author: sanket1729

examples/htlc.rs

@@ -19,7 +19,6 @@ use std::str::FromStr;
 use bitcoin::Network;
 use miniscript::descriptor::Wsh;
 use miniscript::policy::{Concrete, Liftable};
-use miniscript::DescriptorTrait;
 
 fn main() {
     // HTLC policy with 10:1 odds for happy (co-operative) case compared to uncooperative case.
@@ -54,7 +53,7 @@ fn main() {
 
     // Get the scriptPpubkey for this Wsh descriptor.
     assert_eq!(
-        format!("{:x}", htlc_descriptor.spk()),
+        format!("{:x}", htlc_descriptor.script_pubkey()),
         "0020d853877af928a8d2a569c9c0ed14bd16f6a80ce9cccaf8a6150fd8f7f8867ae2"
     );
 
@@ -66,7 +65,7 @@ fn main() {
 
     // Get the address for this Wsh descriptor.v
     assert_eq!(
-        format!("{}", htlc_descriptor.address(Network::Bitcoin).unwrap()),
+        format!("{}", htlc_descriptor.address(Network::Bitcoin)),
         "bc1qmpfcw7he9z5d9ftfe8qw699azmm2sr8fen903fs4plv007yx0t3qxfmqv5"
     );
 }

examples/parse.rs

@@ -17,7 +17,7 @@
 use std::str::FromStr;
 
 use miniscript::descriptor::DescriptorType;
-use miniscript::{Descriptor, DescriptorTrait};
+use miniscript::Descriptor;
 
 fn main() {
     let desc = miniscript::Descriptor::<bitcoin::PublicKey>::from_str(
@@ -44,7 +44,7 @@ fn main() {
     // us to call infallible methods for getting script pubkey.
     if let Descriptor::Wsh(wsh) = &desc {
         assert_eq!(
-            format!("{:x}", wsh.spk()),
+            format!("{:x}", wsh.script_pubkey()),
             "0020daef16dd7c946a3e735a6e43310cb2ce33dfd14a04f76bf8241a16654cb2f0f9"
         );
     }

examples/sign_multisig.rs

@@ -19,7 +19,6 @@ use std::str::FromStr;
 
 use bitcoin::blockdata::witness::Witness;
 use bitcoin::secp256k1;
-use miniscript::DescriptorTrait;
 
 fn main() {
     let mut tx = spending_transaction();

examples/xpub_descriptors.rs

@@ -18,7 +18,7 @@ use std::str::FromStr;
 
 use miniscript::bitcoin::secp256k1::{Secp256k1, Verification};
 use miniscript::bitcoin::{Address, Network};
-use miniscript::{Descriptor, DescriptorPublicKey, DescriptorTrait, TranslatePk2};
+use miniscript::{Descriptor, DescriptorPublicKey, TranslatePk2};
 
 const XPUB_1: &str = "xpub661MyMwAqRbcFW31YEwpkMuc5THy2PSt5bDMsktWQcFF8syAmRUapSCGu8ED9W6oDMSgv6Zz8idoc4a6mr8BDzTJY47LJhkJ8UB7WEGuduB";
 const XPUB_2: &str = "xpub69H7F5d8KSRgmmdJg2KhpAK8SR3DjMwAdkxj3ZuxV27CprR9LgpeyGmXUbC6wb7ERfvrnKZjXoUmmDznezpbZb7ap6r1D3tgFxHmwMkQTPH";

integration_test/src/test_cpp.rs

@@ -13,7 +13,7 @@ use miniscript::miniscript::iter;
 use miniscript::psbt::PsbtExt;
 use miniscript::MiniscriptKey;
 use miniscript::Segwitv0;
-use miniscript::{Descriptor, DescriptorTrait, Miniscript};
+use miniscript::{Descriptor, Miniscript};
 use std::collections::BTreeMap;
 use std::fs::File;
 use std::io::{self, BufRead};

integration_test/src/test_desc.rs

@@ -13,8 +13,8 @@ use bitcoin::util::{psbt, sighash};
 use bitcoin::{self, Amount, OutPoint, SchnorrSig, Script, Transaction, TxIn, TxOut, Txid};
 use bitcoincore_rpc::{json, Client, RpcApi};
 use miniscript::miniscript::iter;
-use miniscript::psbt::{PsbtInputExt, PsbtExt};
-use miniscript::{Descriptor, DescriptorTrait, Miniscript, ToPublicKey};
+use miniscript::psbt::{PsbtExt, PsbtInputExt};
+use miniscript::{Descriptor, Miniscript, ToPublicKey};
 use miniscript::{MiniscriptKey, ScriptContext};
 use std::collections::BTreeMap;