Update library MSRV to 1.63 and edition to 2021 (#120)

1.63 is one year old, and is available in Debian and Ubuntu stable
releases.

Fixes #119.

.github/workflows/rust.yml

@@ -19,58 +19,42 @@ jobs:
           - ubuntu-latest
           - windows-latest
           - macos-latest
-          - macos-11
         rust:
           - stable
-          - 1.46.0 # lib MSRV
+          - msrv
           - 1.64.0 # cli MSRV
         include:
           - os: ubuntu-latest
             rust: stable
             lint: 1
           - rust: stable
             rust-args: --all-features
-          - rust: 1.46.0
-            old-cargo-compat: 1
           - rust: 1.64.0
             rust-args: --all-features
-        exclude:
-          # rust < 1.54 does not work on macos >= 12:
-          # https://rust-lang.zulipchat.com/#narrow/stream/182449-t-compiler.2Fhelp/topic/.E2.9C.94.20How.20can.20I.20fix.20Rust.201.2E53.2E0.20or.20earlier.20to.20run.20on.20macOS.2012.2E6.3F/near/299263887
-          - os: macos-latest
-            rust: 1.46.0
-          - os: macos-11
-            rust: stable
-          - os: macos-11
-            rust: 1.64.0
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout source
         uses: actions/checkout@v2
 
+      - name: Select Rust version
+        shell: bash
+        run: |
+          RUST_VER="${{ matrix.rust }}"
+          if [ "$RUST_VER" = msrv ]; then
+              RUST_VER=$(cargo metadata --format-version 1 --no-deps | \
+                  jq -r '.packages[0].rust_version')
+              echo "MSRV: $RUST_VER"
+          fi
+          echo "RUST_VER=$RUST_VER" >> $GITHUB_ENV
+
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: ${{ matrix.rust }}
+          toolchain: ${{ env.RUST_VER }}
           default: true
           override: true
 
       - uses: Swatinem/rust-cache@v1
 
-      - name: Compatibility fixes for older versions of cargo
-        if: matrix.old-cargo-compat
-        run: |
-          # If we're testing with Rust < 1.60, cargo won't be able to find
-          # the clap version specified in Cargo.lock, so remove the lockfile.
-          # This is safe because applications that only use us as a library
-          # will also ignore our Cargo.lock.
-          # https://users.rust-lang.org/t/optional-dependencies-and-msrv/82151
-          cargo update -p clap --precise 3.2.25
-          # Downgrade the following crates because they require edition 2021
-          cargo update -p serde --precise 1.0.156
-          cargo update -p thiserror --precise 1.0.39
-          cargo update -p quote --precise 1.0.30
-          cargo update -p proc-macro2 --precise 1.0.65
-
       - name: cargo test
         uses: actions-rs/cargo@v1
         with:

Cargo.toml

@@ -3,7 +3,8 @@ name = "gptman"
 version = "1.0.1"
 authors = ["Cecile Tonglet <cecile.tonglet@cecton.com>"]
 license = "MIT OR Apache-2.0"
-edition = "2018"
+edition = "2021"
+rust-version = "1.63"
 description = "A GPT manager that allows you to copy partitions from one disk to another"
 repository = "https://github.com/rust-disk-partition-management/gptman"
 homepage = "https://github.com/rust-disk-partition-management/gptman"
@@ -33,11 +34,7 @@ pad = { version = "0.1", optional = true }
 unicode-width = { version = "0.1.8", optional = true }
 linefeed = { version = "0.6.0", optional = true }
 rand = { version = "0.8", optional = true }
-# We don't actually support clap 3.  But cargo < 1.60 ignores clap versions
-# >= 4, and our MSRV is lower than that when the CLI is disabled.  Ensure
-# older cargo can find _some_ clap version so it won't fail.
-# https://users.rust-lang.org/t/optional-dependencies-and-msrv/82151
-clap = { version = ">= 3, < 5", optional = true, features = ["derive", "wrap_help"] }
+clap = { version = "4", optional = true, features = ["derive", "wrap_help"] }
 count-zeroes = { version = "0.2.0", optional = true }
 
 [features]

README.md

@@ -1,6 +1,6 @@
 ![Rust](https://github.com/rust-disk-partition-management/gptman/actions/workflows/rust.yml/badge.svg)
 [![Latest Version](https://img.shields.io/crates/v/gptman.svg)](https://crates.io/crates/gptman)
-![Rust 1.46+](https://img.shields.io/badge/rust-1.46%2B-orange.svg)
+![Rust 1.63+](https://img.shields.io/badge/rust-1.63%2B-orange.svg)
 ![License](https://img.shields.io/crates/l/gptman)
 [![Docs.rs](https://docs.rs/gptman/badge.svg)](https://docs.rs/gptman)
 [![LOC](https://tokei.rs/b1/github/rust-disk-partition-management/gptman)](https://github.com/rust-disk-partition-management/gptman)