Add optional defmt support for error types

.github/workflows/ci.yml

@@ -21,7 +21,7 @@ jobs:
 
         include:
           # Test MSRV
-          - rust: 1.56.0  # keep in sync with manifest rust-version
+          - rust: 1.62.0  # keep in sync with manifest rust-version
             TARGET: x86_64-unknown-linux-gnu
 
           # Test nightly but don't fail
@@ -45,4 +45,4 @@ jobs:
         if: ${{ contains(matrix.TARGET, 'x86_64') }}
         with:
           command: test
-          args: --target=${{ matrix.TARGET }}
+          args: --target=${{ matrix.TARGET }} --all-features

CHANGELOG.md

@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 
+### Added 
+
+- Support for optional package `defmt` which allows for easy conversion for
+error types when using tools like `probe-rs` for logging over debuggers.
+
 ## [v0.5.1] - 2023-07-26
 
 ### Added

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 = "1.56.0"  # keep in sync with ci, src/lib.rs, and README
+rust-version = "1.62.0"  # keep in sync with ci, src/lib.rs, and README
 keywords = ["serde", "json"]
 license = "MIT OR Apache-2.0"
 name = "serde-json-core"
@@ -23,6 +23,11 @@ optional = true
 default-features = false
 version = "1.0.100"
 
+[dependencies.defmt]
+version = "0.3.5"
+default-features = false
+optional = true
+
 [dev-dependencies]
 serde_derive = "1.0.100"
 

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 1.56.0 and up. It *might*
+This crate is guaranteed to compile on stable Rust 1.62.0 and up. It *might*
 compile with older versions but that may change in any new patch release.
 
 ## License

src/de/mod.rs

@@ -19,6 +19,7 @@ pub type Result<T> = core::result::Result<T, Error>;
 /// This type represents all possible errors that can occur when deserializing JSON data
 #[derive(Debug, PartialEq, Eq, Clone)]
 #[cfg_attr(not(feature = "custom-error-messages"), derive(Copy))]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[non_exhaustive]
 pub enum Error {
     /// EOF while parsing a list.
@@ -74,7 +75,9 @@ pub enum Error {
 
     /// Error with a custom message that was preserved.
     #[cfg(feature = "custom-error-messages")]
-    CustomErrorWithMessage(heapless::String<64>),
+    CustomErrorWithMessage(
+        #[cfg_attr(feature = "defmt", defmt(Debug2Format))] heapless::String<64>,
+    ),
 }
 
 impl serde::de::StdError for Error {}

src/lib.rs

@@ -52,7 +52,7 @@
 //!
 //! # Minimum Supported Rust Version (MSRV)
 //!
-//! This crate is guaranteed to compile on stable Rust 1.56.0 and up. It *might* compile with older
+//! This crate is guaranteed to compile on stable Rust 1.62.0 and up. It *might* compile with older
 //! versions but that may change in any new patch release.
 
 #![deny(missing_docs)]

src/ser/mod.rs

@@ -22,6 +22,7 @@ pub type Result<T> = ::core::result::Result<T, Error>;
 
 /// This type represents all possible errors that can occur when serializing JSON data
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[non_exhaustive]
 pub enum Error {
     /// Buffer is full