Remove cargo_component_bindings crate. (#212)

This commit is a breaking change to `cargo-component` with the intention of
improving component build time (now down to two transitive crate dependencies)
and get `rust-analyzer` fully working with bindings.

It removes the `cargo_component_bindings` and `cargo_component_macro` crates.
Instead of using a macro for including the generated bindings,
`cargo-component` now directly writes to a `src/bindings.rs` file which is
included as a submodule in `main.rs` or `lib.rs`.

Additionally, the `update` subcommand was removed as it is no longer necessary
since there is no `cargo_component_bindings` crate referenced in `Cargo.toml`;
the functionality to update `cargo-component` itself can simply be replaced
with a `cargo install` or `cargo binstall`.

Closes #210.

Cargo.toml

@@ -60,11 +60,10 @@ warg-server = { workspace = true }
 tempfile = { workspace = true }
 
 [workspace]
-members = ["crates/bindings", "crates/macro", "crates/core", "crates/wit"]
+members = ["crates/core", "crates/wit"]
 
 [workspace.dependencies]
 cargo-component-core = { path = "crates/core", version = "0.6.0" }
-cargo-component-macro = { path = "crates/macro", version = "0.6.0" }
 warg-protocol = "0.2.0"
 warg-crypto = "0.2.0"
 warg-client = "0.2.0"
@@ -96,9 +95,6 @@ rand_core = "0.6.4"
 rpassword = "7.3.1"
 futures = "0.3.30"
 bytes = "1.5.0"
-proc-macro2 = "1.0.76"
-quote = "1.0.35"
-syn = "2.0.48"
 which = "5.0.0"
 wit-bindgen-rust = "0.16.0"
 wit-bindgen-core = "0.16.0"

README.md

@@ -231,7 +231,7 @@ The component will export a `hello-world` function returning a string.
 The implementation of the component will be in `src/lib.rs`:
 
 ```rust
-cargo_component_bindings::generate!();
+mod bindings;
 
 use bindings::Guest;
 
@@ -245,11 +245,9 @@ impl Guest for Component {
 }
 ```
 
-The `generate!` macro is responsible for generating the bindings to allow the
-Rust code to export what is expected of the component.
-
-It generates a Rust module named `bindings` containing the types and traits the
-correspond to the world definition.
+The `bindings` module contains the the types and traits that correspond to the 
+world targeted by the component; it is automatically generated by 
+`cargo-component`.
 
 ## Usage
 

ci/publish.rs

@@ -14,8 +14,6 @@ use std::time::Duration;
 
 // note that this list must be topologically sorted by dependencies
 const CRATES_TO_PUBLISH: &[&str] = &[
-    "cargo-component-macro",
-    "cargo-component-bindings",
     "cargo-component-core",
     "wit",
     "cargo-component",
@@ -26,8 +24,6 @@ const CRATES_TO_PUBLISH: &[&str] = &[
 // releases since everything not mentioned here is just an organizational detail
 // that no one else should rely on.
 const PUBLIC_CRATES: &[&str] = &[
-    "cargo-component-macro",
-    "cargo-component-bindings",
     "cargo-component-core",
     "wit",
     "cargo-component",

example/Cargo.toml

@@ -7,7 +7,7 @@ edition = "2021"
 crate-type = ["cdylib"]
 
 [dependencies]
-cargo-component-bindings = { path = "../crates/bindings" }
+wit-bindgen = { version = "0.16.0", default-features = false, features = ["realloc"]}
 
 [package.metadata.component]
 package = "example:component"