Introduce new bdk_coin_select implementation

Cargo.1.48.0.toml

@@ -0,0 +1,4 @@
+[workspace]
+members = [
+    "nursery/coin_select"
+]

build-msrv-crates.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env sh
+trap '
+    signal=$?;
+    cleanup
+    exit $signal;
+' INT
+
+cleanup() {
+    mv Cargo.tmp.toml Cargo.toml 2>/dev/null
+}
+
+cp Cargo.toml Cargo.tmp.toml
+cp Cargo.1.48.0.toml Cargo.toml
+cat Cargo.toml
+cargo build --release
+cleanup

example-crates/keychain_tracker_example_cli/src/lib.rs

@@ -15,7 +15,7 @@ use bdk_chain::{
     sparse_chain::{self, ChainPosition},
     DescriptorExt, FullTxOut,
 };
-use bdk_coin_select::{coin_select_bnb, CoinSelector, CoinSelectorOpt, WeightedValue};
+use bdk_coin_select::{coin_select_bnb, CoinSelector, CoinSelectorOpt, Candidate};
 use bdk_file_store::KeychainStore;
 use clap::{Parser, Subcommand};
 use std::{
@@ -352,7 +352,7 @@ pub fn create_tx<P: ChainPosition>(
     let wv_candidates = candidates
         .iter()
         .map(|(plan, utxo)| {
-            WeightedValue::new(
+            Candidate::new(
                 utxo.txout.value,
                 plan.expected_weight() as _,
                 plan.witness_version().is_some(),

nursery/coin_select/Cargo.toml

@@ -1,10 +1,16 @@
 [package]
 name = "bdk_coin_select"
-version = "0.0.1"
-authors = [ "LLFourn <[email protected]>" ]
+version = "0.1.0"
+edition = "2018"
+license = "MIT OR Apache-2.0"
 
 [dependencies]
-bdk_chain = { path = "../../crates/chain" }
+# No dependencies! Don't add any please!
+
+[dev-dependencies]
+rand = "0.8"
+proptest = "1"
+bitcoin = "0.30"
 
 [features]
 default = ["std"]

nursery/coin_select/README.md

@@ -0,0 +1,59 @@
+# BDK Coin Selection
+
+`bdk_coin_select` is a tool to help you select inputs for making Bitcoin (ticker: BTC) transactions. It's got zero dependencies so you can pasta it into your project without concern.
+
+
+## Synopsis
+
+```rust
+use bdk_coin_select::{CoinSelector, Candidate, TXIN_BASE_WEIGHT};
+use bitcoin::{ Transaction, TxIn };
+
+// You should use miniscript to figure out the satisfaction weight for your coins!
+const tr_satisfaction_weight: u32 = 66;
+const tr_input_weight: u32 = txin_base_weight + tr_satisfaction_weight;
+
+
+let candidates = vec![
+    Candidate {
+        // How many inputs does this candidate represent. Needed so we can figure out the weight
+        // of the varint that encodes the number of inputs.
+        input_count: 1,
+        // the value of the input
+        value: 1_000_000,
+        // the total weight of the input(s). This doesn't include 
+        weight: TR_INPUT_WEIGHT,
+        // wether it's a segwit input. Needed so we know whether to include the segwit header
+        // in total weight calculations.
+        is_segwit: true
+    },
+    Candidate {
+        // A candidate can represent multiple inputs in the case where you always want some inputs 
+        // to be spent together.
+        input_count: 2,
+        weight: 2*tr_input_weight,
+        value: 3_000_000,
+        is_segwit: true
+    },
+    Candidate {
+        input_count: 1,
+        weight: TR_INPUT_WEIGHT,
+        value: 5_000_000,
+        is_segwit: true,
+    }
+];
+
+let base_weight = Transaction {
+    input: vec![],
+    output: vec![],
+    lock_time: bitcoin::absolute::LockTime::from_height(0).unwrap(),
+    version: 1,
+}.weight().to_wu() as u32;
+
+panic!("{}", base_weight);
+
+let mut coin_selector = CoinSelector::new(&candidates,base_weight);
+
+
+```
+