Upgrade clippy and rustfmt

Author: Junha Yang

.github/workflows/cargo-test.yml

@@ -12,7 +12,7 @@ jobs:
           fetch-depth: 1
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: nightly-2020-05-05
+          toolchain: nightly-2020-07-27
           components: clippy
           profile: minimal
           override: true
@@ -28,7 +28,7 @@ jobs:
           fetch-depth: 1
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: nightly-2020-05-05
+          toolchain: nightly-2020-07-27
           components: rustfmt
           profile: minimal
           override: true

README.md

@@ -85,35 +85,35 @@ You can create a block by sending a transaction through [JSON-RPC](https://githu
 
 ## Formatting
 
-Make sure you run `rustfmt` before creating a PR to the repo. You need to install the nightly-2020-05-05 version of `rustfmt`.
+Make sure you run `rustfmt` before creating a PR to the repo. You need to install the nightly-2020-07-27 version of `rustfmt`.
 
 ```sh
-rustup toolchain install nightly-2020-05-05
-rustup component add rustfmt --toolchain nightly-2020-05-05
+rustup toolchain install nightly-2020-07-27
+rustup component add rustfmt --toolchain nightly-2020-07-27
 ```
 
 To run `rustfmt`,
 
 ```sh
-cargo +nightly-2020-05-05 fmt
+cargo +nightly-2020-07-27 fmt
 ```
 
 ## Linting
 
 You should run `clippy` also. This is a lint tool for rust. It suggests more efficient/readable code.
 You can see [the clippy document](https://rust-lang.github.io/rust-clippy/master/index.html) for more information.
-You need to install the nightly-2020-05-05 version of `clippy`.
+You need to install the nightly-2020-07-27 version of `clippy`.
 
 ### Install
 ```sh
-rustup toolchain install nightly-2020-05-05
-rustup component add clippy --toolchain nightly-2020-05-05
+rustup toolchain install nightly-2020-07-27
+rustup component add clippy --toolchain nightly-2020-07-27
 ```
 
 ### Run
 
 ```sh
-cargo +nightly-2020-05-05 clippy --all --all-targets
+cargo +nightly-2020-07-27 clippy --all --all-targets
 ```
 
 ## Testing