This allows porting uses of span_suggestions() to diagnostic structs.
Doesn't work for multipart_suggestions() because the rank would be
reversed - the struct would specify multiple spans, each of which has
multiple possible replacements, while multipart_suggestions() creates
multiple possible replacements, each with multiple spans.
Documentation comments shouldn't affect the diagnostic derive in any
way, but explicit support has to be added for ignoring the `doc`
attribute.
Signed-off-by: David Wood <david.wood@huawei.com>
Following the approach taken in earlier commits to separate formatting
initialization from use in the subdiagnostic derive, simplify the
diagnostic derive by removing the field-ordering logic that previously
solved this problem.
Signed-off-by: David Wood <david.wood@huawei.com>
Diagnostic derives have previously had to take special care when
ordering the generated code so that fields were not used after a move.
This is unlikely for most fields because a field is either annotated
with a subdiagnostic attribute and is thus likely a `Span` and copiable,
or is a argument, in which case it is only used once by `set_arg`
anyway.
However, format strings for code in suggestions can result in fields
being used after being moved if not ordered carefully. As a result, the
derive currently puts `set_arg` calls last (just before emission), such
as:
```rust
let diag = { /* create diagnostic */ };
diag.span_suggestion_with_style(
span,
fluent::crate::slug,
format!("{}", __binding_0),
Applicability::Unknown,
SuggestionStyle::ShowAlways
);
/* + other subdiagnostic additions */
diag.set_arg("foo", __binding_0);
/* + other `set_arg` calls */
diag.emit();
```
For eager translation, this doesn't work, as the message being
translated eagerly can assume that all arguments are available - so
arguments _must_ be set first.
Format strings for suggestion code are now separated into two parts - an
initialization line that performs the formatting into a variable, and a
usage in the subdiagnostic addition.
By separating these parts, the initialization can happen before
arguments are set, preserving the desired order so that code compiles,
while still enabling arguments to be set before subdiagnostics are
added.
```rust
let diag = { /* create diagnostic */ };
let __code_0 = format!("{}", __binding_0);
/* + other formatting */
diag.set_arg("foo", __binding_0);
/* + other `set_arg` calls */
diag.span_suggestion_with_style(
span,
fluent::crate::slug,
__code_0,
Applicability::Unknown,
SuggestionStyle::ShowAlways
);
/* + other subdiagnostic additions */
diag.emit();
```
Signed-off-by: David Wood <david.wood@huawei.com>
Add support for `MultiSpan` with any of the attributes that work on a
`Span` - requires that diagnostic logic generated for these attributes
are emitted in the by-move block rather than the by-ref block that they
would normally have been generated in.
Signed-off-by: David Wood <david.wood@huawei.com>
`SessionDiagnostic` isn't suitable for use on lints as whether or not it
creates an error or a warning is decided at compile-time by the macro,
whereas lints decide this at runtime based on the location of the lint
being reported (as it will depend on the user's `allow`/`deny`
attributes, etc). Re-using most of the machinery for
`SessionDiagnostic`, this macro introduces a `LintDiagnostic` derive
which implements a `DecorateLint` trait, taking a
`LintDiagnosticBuilder` and adding to the lint according to the
diagnostic struct.
Move the logic for building a field mapping (which is used by the
building of format strings in `suggestion` annotations) into a helper
function.
Signed-off-by: David Wood <david.wood@huawei.com>
Type attributes could previously be used to support spanless
subdiagnostics but these couldn't easily be made optional in the same
way that spanned subdiagnostics could by using a field attribute on a
field with an `Option<Span>` type. Spanless subdiagnostics can now be
specified on fields with `()` type or `Option<()>` type.
Signed-off-by: David Wood <david.wood@huawei.com>
Diagnostics can have multiple primary spans, or have subdiagnostics
repeated at multiple locations, so support `Vec<..>` fields in the
diagnostic derive which become loops in the generated code.
Signed-off-by: David Wood <david.wood@huawei.com>
In the initial implementation of the `SessionSubdiagnostic`, the
`Applicability` of a suggestion can be set both as a field and as part
of the attribute, this commit adds the same support to the original
`SessionDiagnostic` derive.
Signed-off-by: David Wood <david.wood@huawei.com>
Split `SessionDiagnostic` and `SessionSubdiagnostic` derives and the
various helper functions into multiple modules.
Signed-off-by: David Wood <david.wood@huawei.com>
