Skip to content

syntax::ext: Make type errors in deriving point to the field itself.#10355

Merged
bors merged 1 commit intorust-lang:masterfrom
huonw:deriving-field-spans
Nov 8, 2013
Merged

syntax::ext: Make type errors in deriving point to the field itself.#10355
bors merged 1 commit intorust-lang:masterfrom
huonw:deriving-field-spans

Conversation

@huonw
Copy link
Contributor

@huonw huonw commented Nov 8, 2013

This rearranges the deriving code so that #[deriving] a trait on a field
that doesn't implement that trait will point to the field in question,
e.g.

struct NotEq; // doesn't implement Eq

#[deriving(Eq)]
struct Foo {
    ok: int,
    also_ok: ~str,
    bad: NotEq // error points here.
}

Unfortunately, this means the error is disconnected from the deriving
itself but there's no current way to pass that information through to
rustc except via the spans, at the moment.

Fixes #7724.

@huonw
syntax::ext: Make type errors in deriving point to the field itself.
812ea9e 
This rearranges the deriving code so that #[deriving] a trait on a field
that doesn't implement that trait will point to the field in question,
e.g.

    struct NotEq; // doesn't implement Eq

    #[deriving(Eq)]
    struct Foo {
        ok: int,
        also_ok: ~str,
        bad: NotEq // error points here.
    }

Unfortunately, this means the error is disconnected from the `deriving`
itself but there's no current way to pass that information through to
rustc except via the spans, at the moment.

Fixes rust-lang#7724.
@huonw huonw mentioned this pull request Nov 8, 2013
Closed
@huonw
Copy link
Contributor Author

huonw commented Nov 8, 2013

Summary: this reuses the spans from the variant and struct_field (ast types) in expand_static_enum_body, summarise_struct, create_struct_pattern and create_enum_pattern to create the span field in the new FieldInfo struct (and the Span parts of StaticFields) which can then be used "downstream" (example) to associate the span of the constructed Exprs with the fields, so any type errors get displayed as if they were caused by that field.

(Sorry for the noise with the span -> trait_span.)

bors added a commit that referenced this pull request Nov 8, 2013
@bors
auto merge of #10355 : huonw/rust/deriving-field-spans, r=alexcrichton
a594a99 
This rearranges the deriving code so that #[deriving] a trait on a field
that doesn't implement that trait will point to the field in question,
e.g.

    struct NotEq; // doesn't implement Eq

    #[deriving(Eq)]
    struct Foo {
        ok: int,
        also_ok: ~str,
        bad: NotEq // error points here.
    }

Unfortunately, this means the error is disconnected from the `deriving`
itself but there's no current way to pass that information through to
rustc except via the spans, at the moment.

Fixes #7724.
@bors bors closed this Nov 8, 2013
@bors bors merged commit 812ea9e into rust-lang:master Nov 8, 2013
@huonw huonw deleted the deriving-field-spans branch November 8, 2013 22:17
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

No reviews

Assignees

No one assigned

Labels

None yet

Projects

None yet

Milestone

No milestone

Development

Successfully merging this pull request may close these issues.

deriving error should point to field which caused the error

3 participants

@huonw @alexcrichton @bors