Bumped MSRV to 1.80 in order to use str::split_at_checked

.github/workflows/ci.yml

@@ -22,7 +22,7 @@ jobs:
 
         include:
           # Test MSRV
-          - rust: 1.62.0  # keep in sync with manifest rust-version
+          - rust: 1.80  # keep in sync with manifest rust-version
             TARGET: x86_64-unknown-linux-gnu
 
           # Test nightly but don't fail

Cargo.toml

@@ -4,7 +4,7 @@ categories = ["no-std"]
 description = "serde-json for no_std programs"
 documentation = "https://docs.rs/serde-json-core"
 edition = "2018"
-rust-version = "1.62.0"  # keep in sync with ci, src/lib.rs, and README
+rust-version = "1.80"  # keep in sync with ci, src/lib.rs, and README
 keywords = ["serde", "json"]
 license = "MIT OR Apache-2.0"
 name = "serde-json-core"

README.md

@@ -12,7 +12,7 @@ This project is developed and maintained by the [rust-embedded-community].
 
 ## Minimum Supported Rust Version (MSRV)
 
-This crate is guaranteed to compile on stable Rust 1.62.0 and up. It *might*
+This crate is guaranteed to compile on stable Rust 1.80 and up. It *might*
 compile with older versions but that may change in any new patch release.
 
 ## License

src/lib.rs

@@ -52,7 +52,7 @@
 //!
 //! # Minimum Supported Rust Version (MSRV)
 //!
-//! This crate is guaranteed to compile on stable Rust 1.62.0 and up. It *might* compile with older
+//! This crate is guaranteed to compile on stable Rust 1.80 and up. It *might* compile with older
 //! versions but that may change in any new patch release.
 
 // #![deny(missing_docs)]

src/str.rs

@@ -25,13 +25,10 @@ fn unescape_next_fragment(
             Some('r') => '\r',
             Some('t') => '\t',
             Some('u') => {
-                fn split_first_slice(s: &str, len: usize) -> Option<(&str, &str)> {
-                    Some((s.get(..len)?, s.get(len..)?))
-                }
-
-                let (escape_sequence, remaining_escaped_string_chars) =
-                    split_first_slice(escaped_string_chars.as_str(), 4)
-                        .ok_or(StringUnescapeError::InvalidEscapeSequence)?;
+                let (escape_sequence, remaining_escaped_string_chars) = escaped_string_chars
+                    .as_str()
+                    .split_at_checked(4)
+                    .ok_or(StringUnescapeError::InvalidEscapeSequence)?;
 
                 escaped_string_chars = remaining_escaped_string_chars.chars();