Fold invariant_context into context

[coord-e]

#[thrust_macros::context] stamped each method of an impl/trait with the enclosing header, while #[thrust_macros::invariant_context] threaded the same header — plus the host signature — into the invariant! calls in a function body. Two attributes for one question: what does the code inside this item see?

They become one. #[thrust_macros::context] now takes a function as well, and an impl/trait hands each of its methods the enclosing header along with the attribute itself, so a method carrying a loop invariant no longer needs one of its own:

#[thrust_macros::context]implCounter{fnrun(&mutself) -> i64{let init = *self;whilerand(){
thrust_macros::invariant!(|init:Self,self:&mutSelf| init.value <= (*self).value);self.value += 1;}
init.value}}

A free function still opts in explicitly, with #[thrust_macros::context] in place of the old name.

Who does what

The impl/trait expansion stays a distributor: it knows which items are methods and what header they sit under, and nothing about what a body holds. It stamps two attributes per method —

#[thrust::_outer_context(implCounter)]#[::thrust_macros::context]fnrun(&mutself) -> i64{ .. }

— and each method's body is then threaded by its own expansion of the attribute, the same one a free function gets, which reads the header back from #[thrust::_outer_context(..)]: the path requires/ensures already take. That expansion accepts a free function, an impl method, or a trait method through the existing FnItemWithSignature, so a trait method with no body needs no special case.

ContextInjector moves over from invariant_context.rs unchanged.

Not extending a where clause nothing asked for

Threading a body that names no invariant! now leaves it alone. invariant_context extended the host's where clause with the Model predicates unconditionally, which was fine while it was opt-in per function; with every method of a #[context] item threaded, those bounds would otherwise land on methods that have no formula to justify them.

Changes

context.rs	dispatches on the item: a function is threaded, an impl/trait hands its methods the header and this attribute. ContextInjector moves here from invariant_context.rs, which is deleted
spec.rs	FnItemWithSignature::sig_mut, to extend the threaded function's where clause
tests/ui	17 files: free functions take #[thrust_macros::context], methods drop the attribute entirely

No behaviour change for the analyzer; the macro expansion each test produces is the same as before.

[Copilot]

Pull request overview

Unifies invariant context propagation under #[thrust_macros::context] for functions, impls, and traits.

Changes:

• Extends context to rewrite invariants and add required model bounds.
• Automatically applies context propagation to impl and trait methods.
• Removes invariant_context and migrates UI tests.

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
thrust-macros/src/context.rs	Implements unified context expansion.
thrust-macros/src/invariant.rs	Updates context documentation.
thrust-macros/src/invariant_context.rs	Removes superseded implementation.
thrust-macros/src/lib.rs	Removes the old attribute and updates exports.
thrust-macros/src/spec.rs	Adds mutable signature access.
tests/ui/pass/loop_invariant_trait.rs	Tests automatic trait-method context.
tests/ui/pass/loop_invariant_trait_self.rs	Tests Self invariants in traits.
tests/ui/pass/loop_invariant_self.rs	Tests automatic impl-method context.
tests/ui/pass/loop_invariant_self_receiver.rs	Tests receiver-based invariants.
tests/ui/pass/loop_invariant_outer_param.rs	Migrates free-function context usage.
tests/ui/pass/loop_invariant_generic.rs	Migrates generic invariant coverage.
tests/ui/pass/loop_invariant_generic_closure.rs	Migrates generic closure coverage.
tests/ui/pass/loop_invariant_fn_param_closure.rs	Migrates closure-parameter coverage.
tests/ui/pass/loop_invariant_fn_param_at_entry.rs	Migrates entry-value coverage.
tests/ui/fail/loop_invariant_trait.rs	Updates failing trait invariant test.
tests/ui/fail/loop_invariant_trait_self.rs	Updates failing trait Self test.
tests/ui/fail/loop_invariant_self.rs	Updates failing impl invariant test.
tests/ui/fail/loop_invariant_self_receiver.rs	Updates failing receiver test.
tests/ui/fail/loop_invariant_outer_param.rs	Updates failing outer-parameter test.
tests/ui/fail/loop_invariant_generic.rs	Updates failing generic test.
tests/ui/fail/loop_invariant_fn_param_closure.rs	Updates failing closure test.
tests/ui/fail/loop_invariant_fn_param_at_entry.rs	Updates failing entry-value test.

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit:36f8ffe231

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".