Merge pull request #31 from audunhalland/next

entrait 0.7

.github/workflows/rust.yml

@@ -15,22 +15,12 @@ jobs:
       - uses: actions/checkout@v3
       - uses: taiki-e/install-action@cargo-hack
       - name: Test feature powerset
-        run: cargo hack --feature-powerset --exclude-features "default use-associated-futures nightly-tests" --exclude-no-default-features test
+        run: cargo hack --feature-powerset --exclude-features "default" --exclude-no-default-features test
       - name: Test workspace
-        run: cargo test --workspace --features "boxed-futures"
+        run: cargo test --workspace --features "unimock"
       - name: Doctest
-        run: cargo test --doc --features "unimock use-boxed-futures"
+        run: cargo test --doc --features "unimock"
       - name: Clippy
-        run: cargo clippy --features "unimock use-boxed-futures" -- -D warnings
+        run: cargo clippy --features "unimock" -- -D warnings
       - name: Build examples
         run: cargo build --all
-
-  test-nightly:
-    runs-on: ubuntu-latest
-
-    steps:
-      - uses: actions/checkout@v3
-      - uses: dtolnay/rust-toolchain@nightly
-      - uses: taiki-e/install-action@cargo-hack
-      - name: Test nightly features
-        run: cargo hack --feature-powerset --exclude-features "default boxed-futures use-boxed-futures" --exclude-no-default-features test

CHANGELOG.md

@@ -5,6 +5,16 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## Unreleased
+### Changed
+- Unimock bumped to 0.6.
+- Reworked async support. Rust now has native support for async functions in traits, which means that entrait doesn't need to interact with this in a hacky way anymore.
+- Minimum Supported Rust Version bumped to 1.75.
+- `async` entrait functions will get rewritten to the `fn f(..) -> impl Future<Output = ?>` form when appearing in trait definitions, due to the [async_fn_in_trait](https://doc.rust-lang.org/beta/rustc/lints/listing/warn-by-default.html#async-fn-in-trait) warn-by-default lint.
+### Added
+- Improved interoperability with the `async_trait` macro, for scenarios where dynamic dispatch-delegation is used in combination with `async`.
+- `?Send` argument to the entrait macro, for allowing opt-out of `Send` bounds for the `Future`s generated from `async` trait methods.
+### Removed
+- features `boxed-futures`, `use-boxed-futures` and `use-associated-futures`.
 
 ## [0.6.0] - 2023-10-15
 ### Changed

Cargo.toml

@@ -1,9 +1,9 @@
 [package]
 name = "entrait"
-version = "0.6.0"
+version = "0.7.0-dev"
 authors = ["Audun Halland <audun.halland@pm.me>"]
 edition = "2021"
-rust-version = "1.60"
+rust-version = "1.75"
 license = "MIT"
 description = "Loosely coupled Rust application design made easy"
 repository = "https://github.com/audunhalland/entrait/"
@@ -13,29 +13,25 @@ categories = ["rust-patterns", "development-tools::testing"]
 [features]
 default = []
 unimock = ["dep:unimock"]
-use-boxed-futures = ["boxed-futures"]
-use-associated-futures = []
-boxed-futures = ["dep:async-trait"]
-nightly-tests = []
 
 [dependencies]
-entrait_macros = { path = "entrait_macros", version = "0.6.0" }
+entrait_macros = { path = "entrait_macros", version = "0.7.0-dev" }
 implementation = "0.1"
-async-trait = { version = "0.1", optional = true }
-unimock = { version = "0.5", optional = true }
+unimock = { version = "0.6.2", optional = true }
 
 [dev-dependencies]
 tokio = { version = "1", features = ["macros", "rt"] }
 feignhttp = "0.5"
-mockall = "0.11"
+mockall = "0.12"
 tracing = "0.1"
+async-trait = "0.1"
 
 [lib]
 # do not run doctest by default with `cargo hack`. They are tested with a separate `cargo test --doc` run.
 doctest = false
 
 [package.metadata.docs.rs]
-features = ["unimock", "use-boxed-futures"]
+features = ["unimock"]
 
 [workspace]
 members = [

README.md

@@ -527,37 +527,10 @@ fn foo<D>(deps: &D) { // <-- private function
 ```
 
 ##### `async` support
-Since Rust at the time of writing does not natively support async methods in traits, you may opt in to having `#[async_trait]` generated for your trait.
-Enable the `boxed-futures` cargo feature and pass the `box_future` option like this:
+Zero-cost async works out of the box.
 
-```rust
-#[entrait(Foo, box_future)]
-async fn foo<D>(deps: &D) {
-}
-```
-This is designed to be forwards compatible with [static async fn in traits](https://rust-lang.github.io/rfcs/3185-static-async-fn-in-trait.html).
-When that day comes, you should be able to just remove that option and get a proper zero-cost future.
-
-There is a cargo feature to automatically apply `#[async_trait]` to every generated async trait: `use-boxed-futures`.
-
-##### Zero-cost async inversion of control - preview mode
-Entrait has experimental support for zero-cost futures. A nightly Rust compiler is needed for this feature.
-
-The entrait option is called `associated_future`, and uses GATs and `feature(type_alias_impl_trait)`.
-This feature generates an associated future inside the trait, and the implementations use `impl Trait` syntax to infer
-the resulting type of the future:
-
-```rust
-#![feature(type_alias_impl_trait)]
-
-use entrait::*;
-
-#[entrait(Foo, associated_future)]
-async fn foo<D>(deps: &D) {
-}
-```
-
-There is a feature for turning this on everywhere: `use-associated-futures`.
+When dynamic dispatch is needed, for example in combination with `delegate_by=ref`, entrait understands the `#[async_trait]` attribute when applied after the entrait macro.
+Entrait will re-apply that macro to the various impl blocks that get generated.
 
 ##### Integrating with other `fn`-targeting macros, and `no_deps`
 Some macros are used to transform the body of a function, or generate a body from scratch.
@@ -598,10 +571,6 @@ It is also possible to reduce noise by doing `use entrait::entrait_export as ent
 | Feature                  | Implies         | Description         |
 | -------------------      | --------------- | ------------------- |
 | `unimock`                |                 | Adds the [unimock] dependency, and turns on Unimock implementations for all traits. |
-| `use-boxed-futures`      | `boxed-futures` | Automatically applies the [async_trait] macro to async trait methods. |
-| `use-associated-futures` |                 | Automatically transforms the return type of async trait methods into an associated future by using type-alias-impl-trait syntax. Requires a nightly compiler. |
-| `boxed-futures`          |                 | Pulls in the [async_trait] optional dependency, enabling the `box_future` entrait option (macro parameter). |
-
 
 
 ## "Philosophy"

entrait_macros/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "entrait_macros"
-version = "0.6.0"
+version = "0.7.0-dev"
 authors = ["Audun Halland <audun.halland@pm.me>"]
 edition = "2021"
 rust-version = "1.60"

entrait_macros/src/attributes.rs

@@ -2,7 +2,7 @@ use crate::analyze_generics::TraitFn;
 use crate::generics::{self, TraitIndirection};
 use crate::idents::CrateIdents;
 use crate::input::FnInputMode;
-use crate::opt::{AsyncStrategy, MockApiIdent, Opts, SpanOpt};
+use crate::opt::{MockApiIdent, Opts};
 use crate::token_util::{comma_sep, push_tokens};
 
 use proc_macro2::{Span, TokenStream};
@@ -229,58 +229,22 @@ impl ToTokens for MockallAutomockParams {
     }
 }
 
-pub fn opt_async_trait_attr<'s, 'o>(
-    opts: &'s Opts,
-    crate_idents: &'s CrateIdents,
-    trait_fns: impl Iterator<Item = &'o TraitFn>,
-) -> Option<impl ToTokens + 's> {
-    match (
-        opts.async_strategy(),
-        generics::has_any_async(trait_fns.map(|trait_fn| trait_fn.sig())),
-    ) {
-        (SpanOpt(AsyncStrategy::BoxFuture, span), true) => Some(Attr(AsyncTraitParams {
-            crate_idents,
-            use_static: false,
-            span,
-        })),
-        (SpanOpt(AsyncStrategy::AssociatedFuture, span), true) => Some(Attr(AsyncTraitParams {
-            crate_idents,
-            use_static: true,
-            span,
-        })),
-        _ => None,
-    }
-}
-
 pub struct AsyncTraitParams<'a> {
     pub crate_idents: &'a CrateIdents,
-    pub use_static: bool,
     pub span: Span,
 }
 
 impl<'a> ToTokens for AsyncTraitParams<'a> {
     fn to_tokens(&self, stream: &mut TokenStream) {
         let span = self.span;
-        if self.use_static {
-            push_tokens!(
-                stream,
-                syn::token::PathSep(span),
-                self.crate_idents.entrait,
-                syn::token::PathSep(span),
-                syn::Ident::new("static_async", span),
-                syn::token::PathSep(span),
-                syn::Ident::new("async_trait", span)
-            );
-        } else {
-            push_tokens!(
-                stream,
-                syn::token::PathSep(span),
-                self.crate_idents.entrait,
-                syn::token::PathSep(span),
-                syn::Ident::new("__async_trait", span),
-                syn::token::PathSep(span),
-                syn::Ident::new("async_trait", span)
-            );
-        }
+        push_tokens!(
+            stream,
+            syn::token::PathSep(span),
+            self.crate_idents.entrait,
+            syn::token::PathSep(span),
+            syn::Ident::new("__async_trait", span),
+            syn::token::PathSep(span),
+            syn::Ident::new("async_trait", span)
+        );
     }
 }

entrait_macros/src/entrait_fn/input_attr.rs

@@ -21,8 +21,8 @@ impl Parse for EntraitFnAttr {
 
         let mut no_deps = None;
         let mut debug = None;
-        let mut async_strategy = None;
         let mut export = None;
+        let mut future_send = None;
         let mut mock_api = None;
         let mut unimock = None;
         let mut mockall = None;
@@ -33,13 +33,8 @@ impl Parse for EntraitFnAttr {
             match input.parse::<EntraitOpt>()? {
                 EntraitOpt::NoDeps(opt) => no_deps = Some(opt),
                 EntraitOpt::Debug(opt) => debug = Some(opt),
-                EntraitOpt::BoxFuture(opt) => {
-                    async_strategy = Some(SpanOpt(AsyncStrategy::BoxFuture, opt.1))
-                }
-                EntraitOpt::AssociatedFuture(opt) => {
-                    async_strategy = Some(SpanOpt(AsyncStrategy::AssociatedFuture, opt.1))
-                }
                 EntraitOpt::Export(opt) => export = Some(opt),
+                EntraitOpt::MaybeSend(send) => future_send = Some(send),
                 EntraitOpt::MockApi(ident) => mock_api = Some(ident),
                 EntraitOpt::Unimock(opt) => unimock = Some(opt),
                 EntraitOpt::Mockall(opt) => mockall = Some(opt),
@@ -56,8 +51,8 @@ impl Parse for EntraitFnAttr {
                 default_span,
                 no_deps,
                 debug,
-                async_strategy,
                 export,
+                future_send,
                 mock_api,
                 unimock,
                 mockall,

entrait_macros/src/entrait_fn/mod.rs

@@ -13,6 +13,7 @@ use crate::generics;
 use crate::input::FnInputMode;
 use crate::input::{InputFn, InputMod, ModItem};
 use crate::signature;
+use crate::sub_attributes::analyze_sub_attributes;
 use crate::trait_codegen::Supertraits;
 use crate::trait_codegen::TraitCodegen;
 use input_attr::*;
@@ -33,22 +34,21 @@ pub fn entrait_for_single_fn(attr: &EntraitFnAttr, input_fn: InputFn) -> syn::Re
         opts: &attr.opts,
     }
     .analyze(input_fn.input_sig(), &mut generics_analyzer)?];
+    let sub_attributes = analyze_sub_attributes(&input_fn.fn_attrs);
 
     let trait_dependency_mode = detect_trait_dependency_mode(
         &fn_input_mode,
         &trait_fns,
         &attr.crate_idents,
         attr.trait_ident.span(),
     )?;
-    let use_associated_future =
-        generics::detect_use_associated_future(&attr.opts, [&input_fn].into_iter());
-
     let trait_generics = generics_analyzer.into_trait_generics();
     let trait_def = TraitCodegen {
         opts: &attr.opts,
         crate_idents: &attr.crate_idents,
         trait_indirection: generics::TraitIndirection::Plain,
         trait_dependency_mode: &trait_dependency_mode,
+        sub_attributes: &sub_attributes,
     }
     .gen_trait_def(
         &attr.trait_visibility,
@@ -58,6 +58,7 @@ pub fn entrait_for_single_fn(attr: &EntraitFnAttr, input_fn: InputFn) -> syn::Re
         &trait_fns,
         &fn_input_mode,
     )?;
+
     let impl_block = fn_delegation_codegen::FnDelegationCodegen {
         opts: &attr.opts,
         crate_idents: &attr.crate_idents,
@@ -67,7 +68,7 @@ pub fn entrait_for_single_fn(attr: &EntraitFnAttr, input_fn: InputFn) -> syn::Re
         trait_generics: &trait_generics,
         fn_input_mode: &fn_input_mode,
         trait_dependency_mode: &trait_dependency_mode,
-        use_associated_future,
+        sub_attributes: &sub_attributes,
     }
     .gen_impl_block(&trait_fns);
 
@@ -79,11 +80,15 @@ pub fn entrait_for_single_fn(attr: &EntraitFnAttr, input_fn: InputFn) -> syn::Re
         ..
     } = input_fn;
 
-    Ok(quote! {
+    let out = quote! {
         #(#fn_attrs)* #fn_vis #fn_sig #fn_body
         #trait_def
         #impl_block
-    })
+    };
+
+    // println!("\n\nfn output: {out}");
+
+    Ok(out)
 }
 
 pub fn entrait_for_mod(attr: &EntraitFnAttr, input_mod: InputMod) -> syn::Result<TokenStream> {
@@ -103,24 +108,22 @@ pub fn entrait_for_mod(attr: &EntraitFnAttr, input_mod: InputMod) -> syn::Result
             .analyze(input_fn.input_sig(), &mut generics_analyzer)
         })
         .collect::<syn::Result<Vec<_>>>()?;
+    let sub_attributes = analyze_sub_attributes(&input_mod.attrs);
 
     let trait_dependency_mode = detect_trait_dependency_mode(
         &fn_input_mode,
         &trait_fns,
         &attr.crate_idents,
         attr.trait_ident.span(),
     )?;
-    let use_associated_future = generics::detect_use_associated_future(
-        &attr.opts,
-        input_mod.items.iter().filter_map(ModItem::filter_pub_fn),
-    );
 
     let trait_generics = generics_analyzer.into_trait_generics();
     let trait_def = TraitCodegen {
         opts: &attr.opts,
         crate_idents: &attr.crate_idents,
         trait_indirection: generics::TraitIndirection::Plain,
         trait_dependency_mode: &trait_dependency_mode,
+        sub_attributes: &sub_attributes,
     }
     .gen_trait_def(
         &attr.trait_visibility,
@@ -139,7 +142,7 @@ pub fn entrait_for_mod(attr: &EntraitFnAttr, input_mod: InputMod) -> syn::Result
         trait_generics: &trait_generics,
         fn_input_mode: &fn_input_mode,
         trait_dependency_mode: &trait_dependency_mode,
-        use_associated_future,
+        sub_attributes: &sub_attributes,
     }
     .gen_impl_block(&trait_fns);
 

entrait_macros/src/entrait_impl/input_attr.rs

@@ -52,8 +52,8 @@ impl Parse for EntraitSimpleImplAttr {
                 default_span: span,
                 no_deps: None,
                 debug,
-                async_strategy: None,
                 export: None,
+                future_send: None,
                 mock_api: None,
                 unimock: None,
                 mockall: None,
@@ -96,8 +96,8 @@ impl Parse for EntraitImplAttr {
                 default_span: span,
                 no_deps: None,
                 debug,
-                async_strategy: None,
                 export: None,
+                future_send: None,
                 mock_api: None,
                 unimock: None,
                 mockall: None,