Merge #63: Improve crate

ddd61f0 Remove unnecessary section from manifest (Tobin C. Harding)
7a4fbbf Improve the library level rustdoc (Tobin C. Harding)
1b464ae Improve rustdocs on error type (Tobin C. Harding)
2bbfc28 Only derive Debug for error type (Tobin C. Harding)
07f80cc Remove unnecessary cast (Tobin C. Harding)
4922750 rustfmt: Use fn_params_layout (Tobin C. Harding)
1faa8f0 rustfmt: Remove required_version (Tobin C. Harding)

Pull request description:

  Go through rust-bitcoin/rust-bitcoin#1649 and attempt to verify that we have every t crossed and i dotted.

  With this PR I believe we could consider stabilising the `bitcoinconsensus` crate, am I wrong? Are there any considerations re the semver number we are using or the fact that we are wrapping 0.20.0 Bitcoin Core?

ACKs for top commit:
  apoelstra:
    ACK ddd61f0

Tree-SHA512: 794c7bc2c06e8418470b8b591bfb2d48e059bd3599793ee150bdc96918504a0cd7702f6e87fa878ef63d2f10fd917fc38d3f57ed1a52a92af31767efe3fb9ecf

Author: apoelstra

Cargo.toml

@@ -13,10 +13,6 @@ exclude = ["/depend/bitcoin/.github/**", "/depend/bitcoin/.tx/**", "/depend/bitc
 build = "build.rs"
 edition = "2018"
 
-[lib]
-name = "bitcoinconsensus"
-path = "src/lib.rs"
-
 [features]
 default = ["std"]
 std = []

rustfmt.toml

@@ -50,7 +50,7 @@ enum_discrim_align_threshold = 0
 match_arm_blocks = false        # Default true
 match_arm_leading_pipes = "Never"
 force_multiline_blocks = false
-fn_args_layout = "Tall"
+fn_params_layout = "Tall"
 brace_style = "SameLineWhere"
 control_brace_style = "AlwaysSameLine"
 trailing_semicolon = true
@@ -68,7 +68,6 @@ use_field_init_shorthand = false
 force_explicit_abi = true
 condense_wildcard_suffixes = false
 color = "Auto"
-required_version = "1.5.1"
 unstable_features = false
 disable_all_formatting = false
 skip_children = false

src/lib.rs

@@ -4,16 +4,28 @@
 //! This project builds the `libbitcoinconsensus` library from Bitcoin's C++
 //! sources using Cargo and provides Rust bindings to its API.
 //!
+//! Quoting from [`bitcoin/doc/shared-libraries.md`]:
+//!
+//! > The purpose of this library is to make the verification functionality that is critical to
+//! > Bitcoin's consensus available to other applications, e.g. to language bindings.
+//!
+//! And that is exactly what this library is, the Rust bindings to `bitcoinconsensus`.
+//!
+//! [`bitcoin/doc/shared-libraries`]: <https://github.com/bitcoin/bitcoin/blob/master/doc/shared-libraries.md>
 
 mod types;
 
 use core::fmt;
 
 use crate::types::*;
 
-/// Errors returned by `libbitcoinconsensus` (see github.com/bitcoin/bitcoin/doc/shared-libraries.md).
+/// Errors returned by [`libbitcoinconsensus`].
+///
+/// The error variant identifiers mimic those from `libbitcoinconsensus`.
+///
+/// [`libbitcoinconsensus`]: <https://github.com/bitcoin/bitcoin/blob/master/doc/shared-libraries.md#errors>
 #[allow(non_camel_case_types)]
-#[derive(PartialEq, Eq, PartialOrd, Ord, Hash, Debug, Clone, Copy)]
+#[derive(Debug)]
 #[repr(C)]
 pub enum Error {
     /// Default value, passed to `libbitcoinconsensus` as a return parameter.
@@ -118,7 +130,7 @@ pub fn height_to_flags(height: u32) -> u32 {
         flag |= VERIFY_NULLDUMMY | VERIFY_WITNESS
     }
 
-    flag as u32
+    flag
 }
 
 /// Returns `libbitcoinconsensus` version.
@@ -185,7 +197,7 @@ pub fn verify_with_flags(
         let ret = bitcoinconsensus_verify_script_with_amount(
             spent_output_script.as_ptr(),
             spent_output_script.len() as c_uint,
-            amount as u64,
+            amount,
             spending_transaction.as_ptr(),
             spending_transaction.len() as c_uint,
             input_index as c_uint,