Enable edition 2018 (#57)

* Update MSRV in CI and Readme from 1.29 to 1.41.1

It seems we have consensus within the rust-bitcoin github organisation
on bumping the MSRV to 1.41.1, update CI job and the README to reflect
this.

* Update to use edition 2018

Add `edition = 2018` to the manifest file. No further changes were
necessary.

* Remove unneeded reference

Clippy emits:

  error: this expression borrows a reference (`&str`) that is
  immediately dereferenced by the compiler

As suggested, remove the unneeded reference.

* Use long literal separators

Clippy emits:

 warning: long literal lacking separators

As suggested, use separators.

* Use contains combinator instead of manual impl

Clippy emits:

 warning: manual `!RangeInclusive::contains` implementation

Use the code snippets suggested by clippy.

* Allow type_complexity

Clippy emits:

 warning: very complex type used. Consider factoring parts into `type` definitions

This code is in a unit test, its clear enough for the purpose.

Configure clippy to allow type_complexity

* Bump version 0.8.1 -> 0.9.0

We just bumped the MSRV, this is a major change but since we are pre 1.0
we just have to bump the minor version number.

Bump version from current `0.8.1` to `0.9.0`.

.github/workflows/rust.yml

@@ -9,7 +9,7 @@ jobs:
     strategy:
       matrix:
         rust:
-          - 1.29.0
+          - 1.41.1
           - stable
           - nightly
     steps:

Cargo.toml

@@ -1,13 +1,14 @@
 [package]
 name = "bech32"
-version = "0.8.1"
+version = "0.9.0"
 authors = ["Clark Moody"]
 repository = "https://github.com/rust-bitcoin/rust-bech32"
 description = "Encodes and decodes the Bech32 format"
 readme = "README.md"
 keywords = ["base32", "encoding", "bech32"]
 categories = ["encoding"]
 license = "MIT"
+edition = "2018"
 
 [features]
 default = ["std"]

README.md

@@ -10,7 +10,5 @@ You can find some usage examples in the [documentation](https://docs.rs/bech32/)
 Bitcoin-specific address encoding is handled by the `bitcoin-bech32` crate.
 
 # MSRV
-The minimum supported Rust version with the standard library is **1.29**.
-
-With nostd, we use the `alloc` dependency, so the MSRV is instead **1.36**.
+The minimum supported Rust version with the standard library is **1.41.1**.
 

clippy.toml

@@ -1 +1 @@
-msrv = "1.29.0"
+msrv = "1.41.1"

src/lib.rs

@@ -370,13 +370,13 @@ fn check_hrp(hrp: &str) -> Result<Case, Error> {
     let mut has_upper: bool = false;
     for b in hrp.bytes() {
         // Valid subset of ASCII
-        if b < 33 || b > 126 {
+        if !(33..=126).contains(&b) {
             return Err(Error::InvalidChar(b as char));
         }
 
-        if b >= b'a' && b <= b'z' {
+        if (b'a'..=b'z').contains(&b) {
             has_lower = true;
-        } else if b >= b'A' && b <= b'Z' {
+        } else if (b'A'..=b'Z').contains(&b) {
             has_upper = true;
         };
 
@@ -406,7 +406,7 @@ pub fn encode_to_fmt<T: AsRef<[u5]>>(
     data: T,
     variant: Variant,
 ) -> Result<fmt::Result, Error> {
-    let hrp_lower = match check_hrp(&hrp)? {
+    let hrp_lower = match check_hrp(hrp)? {
         Case::Upper => Cow::Owned(hrp.to_lowercase()),
         Case::Lower | Case::None => Cow::Borrowed(hrp),
     };
@@ -432,7 +432,7 @@ pub enum Variant {
 }
 
 const BECH32_CONST: u32 = 1;
-const BECH32M_CONST: u32 = 0x2bc830a3;
+const BECH32M_CONST: u32 = 0x2bc8_30a3;
 
 impl Variant {
     // Produce the variant based on the remainder of the polymod operation
@@ -485,7 +485,7 @@ pub fn decode(s: &str) -> Result<(String, Vec<u5>, Variant), Error> {
         return Err(Error::InvalidLength);
     }
 
-    let mut case = check_hrp(&raw_hrp)?;
+    let mut case = check_hrp(raw_hrp)?;
     let hrp_lower = match case {
         Case::Upper => raw_hrp.to_lowercase(),
         // already lowercase
@@ -520,7 +520,7 @@ pub fn decode(s: &str) -> Result<(String, Vec<u5>, Variant), Error> {
             // c should be <128 since it is in the ASCII range, CHARSET_REV.len() == 128
             let num_value = CHARSET_REV[c as usize];
 
-            if num_value > 31 || num_value < 0 {
+            if !(0..=31).contains(&num_value) {
                 return Err(Error::InvalidChar(c));
             }
 
@@ -529,7 +529,7 @@ pub fn decode(s: &str) -> Result<(String, Vec<u5>, Variant), Error> {
         .collect::<Result<Vec<u5>, Error>>()?;
 
     // Ensure checksum
-    match verify_checksum(&hrp_lower.as_bytes(), &data) {
+    match verify_checksum(hrp_lower.as_bytes(), &data) {
         Some(variant) => {
             // Remove checksum from data payload
             let dbl: usize = data.len();
@@ -803,6 +803,7 @@ mod tests {
     }
 
     #[test]
+    #[allow(clippy::type_complexity)]
     fn valid_conversion() {
         // Set of [data, from_bits, to_bits, pad, result]
         let tests: Vec<(Vec<u8>, u32, u32, bool, Vec<u8>)> = vec![