v0.10.1

Bug fixes

This patch release contains a single fix to prevent bindings being generated for cargo projects that are not meant to be components.

Bindings generation now only occurs based on either:

• The presence of a [package.metadata.component] section in Cargo.toml (the default for cargo component new projects).
• The presence of a wit directory in the project.

Compatibility

• Wasmtime: 17.0.0+
• WASI: 0.2.0
• Warg (registry support): 0.4.0

What's Changed

• Prevent bindings generation for normal cargo projects. by @peterhuene in #260
• Bump cargo-component version to 0.10.1. by @peterhuene in #261

Full Changelog: v0.10.0...v0.10.1

v0.10.0

New features

The biggest change included in this release is the support for the latest Warg registry protocol (including registry auth tokens) and also moved the keyring management out of cargo-component and into the warg-credentials crate.

Bug fixes

The code generated by cargo component new --target now properly works with the latest generated bindings when the target world contains exports with resources; it now generates a scaffolding type to implement a resource and sets the trait-associated type when generating interface implementations.

Compatibility

• Wasmtime: 17.0.0+
• WASI: 0.2.0
• Warg (registry support): 0.4.0

What's Changed

• Fix panic in bindings generation for component dependencies. by @peterhuene in #253
• Fix new --target option for exports with resources. by @peterhuene in #254
• rely on warg-credentials for keyring management by @macovedj in #251
• Bump version to 0.10.0. by @peterhuene in #256

Full Changelog: v0.9.1...v0.10.0

v0.9.1

Issues fixed

This release contains a fix introduced in wit-bindgen 0.21.0 to eliminate trailing whitespace that was causing the automatic formatting of the generated bindings to fail.

Users that applied the workaround of setting package.metadata.component.bindings.format to false in Cargo.toml are encouraged to remove the setting after upgrading to 0.9.1; if formatting continues to fail, please let us know by filing an issue.

Users may wish to update the version of the wit-bindgen-rt dependency in Cargo.toml to 0.21.0, but that should not be required.

Upgrading from previous versions

If upgrading from a version of cargo-component older than 0.9.0, please see the release notes for the 0.9.0 release that details several breaking changes.

Compatibility

• Wasmtime: 17.0.0+
• WASI: 0.2.0
• Warg (registry support): 0.3.0

What's Changed

• Update to wit-bindgen 0.21. by @sunfishcode in #247
• Bump cargo-component to 0.9.1. by @peterhuene in #249

Full Changelog: v0.9.0...v0.9.1

v0.9.0

⚠️ Breaking Changes ⚠️

There are a few breaking changes in this release that impact existing cargo-component projects.

The reintroduction of the export! macro

The latest generated bindings has reintroduced the export! macro; an invocation of this macro is required for the core module built from the Rust sources to export the required items.

Building your project without an export! invocation may result in this error message:

error: module does not export required function `<name>`

To fix this, add the following to your src/lib.rs:

bindings::export!(Component with_types_in bindings);

Where Component is the name of the type implementing the generated bindings traits.

Changes to dependencies

To further reduce the chances of a wit-bindgen change breaking cargo-component, a new crate named wit-bindgen-rt was introduced which contains only the runtime functions necessary for bindings to work.

Please replace the following in Cargo.toml:

wit-bindgen = { version = "<version>", default-features = false, features = ["realloc"]} 

with:

bitflags = "2.4.2"
wit-bindgen-rt = "0.20.0"

Changes to [package.metadata.component.bindings] in Cargo.toml

With the reintroduction of the export! macro, the implementor and resources settings that were used to customize the implementing type names in user code have been removed.

Remove these two settings if previously used.

For replacing the implementor setting, pass the implementing type name (e.g. MyImplementingType) to the export! macro:

bindings::export!(MyImplementingType with_types_in bindings);

For replacing the resources setting, use the trait-associated type to specify the implementing resource type:

struct MyResource;

impl bindings::exports::example::Guest for Component {
    type MyResource = MyResource;

    // ...
}

With the implementing types now expressed directly in Rust source, this should hopefully improve compiler diagnostics when there is a mismatch.

Automatic Source Formatting of Generated Bindings

This release of cargo-component includes a feature to automatically format the source code of the generated bindings.

However, rustfmt may fail on overly complex generated source. We've opened an issue to help with that.

You may observe a failure to format the source code of the form:

warning: rustfmt has failed to format.

thread 'main' panicked at .../wit-bindgen-rust-0.20.0/src/lib.rs:1107:13:
assertion failed: status.success()

To work around this issue, disable the source formatting of the generated bindings with:

[package.metadata.component.bindings]
format = false

Highlights

• cargo-component now componentizes based off the presence of bindings type information in the core module rather than expecting that [package.metadata.component] section exists in Cargo.toml, an often confusing way cargo-component worked previously.
• The run, bench, and test commands now print out what is being run like the corresponding commands in cargo.
• Added aarch64-unknown-linux-gnu binary artifact, which should now work with cargo-binstall (thanks to @nacardin).

Compatibility

• Wasmtime: 17.0.0+
• WASI: 0.2.0
• Warg (registry support): 0.3.0

What's Changed

• Update dependencies to latest. by @peterhuene in #237
• Various improvements to cargo-component. by @peterhuene in #240
• Support building aarch64-unknown-linux-gnu binary by @nacardin in #232
• Bump dependencies to latest. by @peterhuene in #243
• Remove status section from the README. by @peterhuene in #244

New Contributors

• @nacardin made their first contribution in #232

Full Changelog: v0.8.0...v0.9.0

v0.8.0

Compatibility

• Wasmtime: 17.0.0+
• WASI: 0.2.0
• Warg (registry support): 0.3.0

What's Changed

• Add support for std_feature by @sunfishcode in #231
• Implement unlocked-dep imports for component dependencies. by @peterhuene in #230
• Update to wit-component 0.21 and wit-parser 0.14. by @sunfishcode in #233
• Bump version to 0.8.0. by @peterhuene in #234

Full Changelog: v0.7.1...v0.8.0

v0.7.1

Compatibility

• Wasmtime: 17.0.0+
• WASI: 0.2.0 (stable preview 2! 🎉)
• Warg (registry support): 0.2.0

What's Changed

• Update the README. by @peterhuene in #218
• Update CI to setup wasmtime via release artifacts. by @peterhuene in #219
• Add a package.metadata.component.proxy setting. by @peterhuene in #221
• Add missing GH token for installing Wasmtime. by @peterhuene in #222
• Use workspace_default_packages now that it is implemented. by @peterhuene in #220
• tests fix by @macovedj in #223
• Bump for 0.7.1 release. by @peterhuene in #228

Full Changelog: v0.7.0...v0.7.1

v0.7.0

⚠️ Breaking changes ⚠️

There are two breaking changes in this release.

1. cargo-component-bindings removed

This breaking change requires manual intervention for existing cargo-component projects to get those projects to build with this release.

cargo-component-bindings has been removed as a dependency; bindings are now directly generated into a src/bindings.rs submodule by cargo-component with no macro involved.

Existing cargo-component projects can be fixed with the following steps:

1. Install the latest cargo-component.

   With the removal of the upgrade subcommand (see below), the latest version of cargo-component can be installed with either cargo install cargo-component or cargo binstall cargo-component (requires cargo-binstall).

2. Edit Cargo.toml:

   Replace the existing cargo-component-bindings dependency with:

   wit-bindgen = { version = "0.16.0", default-features = false, features = ["realloc"] }

   This makes the wit-bindgen runtime functions / types available to the generated code (but does not make the wit-bindgen::generate! macro available).

3. Edit src/main.rs or src/lib.rs:

   Depending on the whether the project is a command (src/main.rs) or a library (src/lib.rs), edit the file to replace the cargo_component_bindings::generate! macro invocation with:

   mod bindings;

2. cargo component update subcommand removed.

With the removal of the cargo-component-bindings crate, the subcommand became a less-functional wrapper around cargo install.

To update cargo-component in the future, use cargo install cargo-component or cargo binstall cargo-component (requires cargo-binstall).

Compatibility

• Wasmtime: 17.0.0
• WASI: 0.2.0 (stable preview 2! 🎉)
• Warg (registry support): 0.2.0

What's Changed

• Update crate dependencies. by @peterhuene in #208
• Check workspace with all targets in vscode, emacs configs by @tomasol in #205
• Use current package with add, publish when in a workspace by @tomasol in #206
• Rename --reactor to --lib for new subcommand. by @peterhuene in #211
• Remove cargo_component_bindings crate. by @peterhuene in #212
• Spawn cargo add in the new command by @tomasol in #209
• Update the adapter to Wasmtime 17.0 and WASI Preview 2. by @sunfishcode in #213
• Update dependencies to latest. by @peterhuene in #214
• Bump cargo-component to 0.7.0. by @peterhuene in #215

New Contributors

• @tomasol made their first contribution in #205

Full Changelog: v0.6.0...v0.7.0

v0.6.0

Compatibility

• Wasmtime: 16.0.0
• Warg (registry support): 0.2.0

Highlight

Thanks to @eduardomourar for contributing a run, test, and bench subcommand to cargo-component.

What's Changed

• Update README Rust-analyzer setting by @vwkd in #197
• feat: support run, test and bench cargo commands by @eduardomourar in #143

New Contributors

• @vwkd made their first contribution in #197

Full Changelog: v0.5.0...v0.6.0

v0.5.0

⚠️ Breaking changes ⚠️

• WIT files now require semicolons at the end of most lines.

Compatibility

• Wasmtime: 15.0.0
• Warg (registry support): 0.2.0

What's Changed

• Update README installation instructions. by @peterhuene in #169
• Update wasm-tools dependencies by @alexcrichton in #176
• Add upgrade subcommand by @jeffparsons in #175
• Better error message when deserializing RegistryPackage by @rylev in #180
• Suppress dead code warnings in bindings. by @peterhuene in #182
• Ensure CI runs on release branches. by @peterhuene in #184
• Add semicolons to WIT. by @peterhuene in #185
• Merge release-0.4.0 to main. by @peterhuene in #186
• Update crate dependencies. by @peterhuene in #190
• Fix bindings version warning and upgrade command. by @peterhuene in #187
• Update README instructions by @nated0g in #193
• Bump version to 0.5.0 by @peterhuene in #195

New Contributors

• @nated0g made their first contribution in #193

Full Changelog: v0.4.0...v0.5.0

v0.4.1

Compatibility

• Wasmtime: 14.0.0
• Warg (registry support): 0.2.0

What's Changed

This release contains a fix for unused code warnings come from bindings, usually as a result of having unused imported functions.

• Cherry pick fix for 0.4.1 release. by @peterhuene in #183

Full Changelog: v0.4.0...v0.4.1