Bump MSRV to 1.59.0 and prepare 1.4.0 release

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ jobs:
       matrix:
         toolchain:
           # Don't forget to update the README when bumping MSRV.
-          - 1.56.1
+          - 1.59.0
           - stable
           - beta
           - nightly

CHANGELOG.md

@@ -1,9 +1,15 @@
+### v1.4.0 (2023-09-19)
+
+- **Changes**:
+    - Bump minimum supported Rust version to 1.59.0 (released 2022-02-24). This is for compatibility with new versions of some of rangemap's test dependencies.
+
+
 ### v1.3.1 (2023-09-19)
 
 - **Fixes**:
     - Fix `PartialEq`, `PartialOrd`, and `Ord` implementations for `RangeMap` (and `RangeSet`). These previously only compared the starts of ranges instead of the entire range. Thanks to https://github.com/hecrj for finding and fixing this!
 - **Changes**:
-    - Minimum supported Rust version for running this crate's tests has increased (I think to 1.59) due to a corresponding MSRV bump in a test dependency. This is causing CI builds to fail against rustc 1.56.1, but should not affect consumers of the crate. The next minor release (1.4.0) will bump the minimum supported Rust version of rangemap itself.
+    - Minimum supported Rust version for running this crate's tests has increased (I think to 1.59.0) due to a corresponding MSRV bump in a test dependency. This is causing CI builds to fail against rustc 1.56.1, but should not affect consumers of the crate. The next minor release (1.4.0) will bump the minimum supported Rust version of rangemap itself.
 
 
 ### v1.3.0 (2023-01-03)

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rangemap"
-version = "1.3.1"
+version = "1.4.0"
 authors = ["Jeff Parsons <[email protected]>"]
 edition = "2018"
 license = "MIT/Apache-2.0"

README.md

@@ -3,7 +3,7 @@
 [![Crate](https://img.shields.io/crates/v/rangemap.svg)](https://crates.io/crates/rangemap)
 [![Docs](https://docs.rs/rangemap/badge.svg)](https://docs.rs/rangemap)
 [![Build status](https://github.com/jeffparsons/rangemap/workflows/CI/badge.svg)](https://github.com/jeffparsons/rangemap/actions)
-[![Rust](https://img.shields.io/badge/rust-1.56.1%2B-blue.svg?maxAge=3600)](https://github.com/jeffparsons/rangemap) <!-- Don't forget to update the GitHub actions config when bumping minimum Rust version. -->
+[![Rust](https://img.shields.io/badge/rust-1.59.0%2B-blue.svg?maxAge=3600)](https://github.com/jeffparsons/rangemap) <!-- Don't forget to update the GitHub actions config when bumping minimum Rust version. -->
 
 [`RangeMap`] and [`RangeInclusiveMap`] are map data structures whose keys
 are stored as ranges. Contiguous and overlapping ranges that map to the same