mirror of
https://github.com/carbon-language/carbon-lang.git
synced 2026-09-24 21:50:14 +01:00
Dana Jansens
fbc8d59d32
Introduces `Context` and `SoftContext` messages, which can be introduced
through a `ContextBuilder`:
- The `Context` messages come before the diagnostic in the output.
- The first `Context` message steals the diagnostic level from the main
diagnostic, and turns the main diagnostic into a Note attached to the
context.
- A `SoftContext` message works similarly, but if it's preceeded by a
`Context` or `SoftContext` message, then it is dropped. This can be used
as a default/backup scope when nothing more interesting is provided up
the stack, such as in `TryEvalBlockForSpecific`.
The `ContextBuilder` is provided to a callback through
`Diagnostics::ContextScope`, an RAII type `AnnotationScope` but for
context messages.
This allows a high level operation to provide a context message like
"failed to identify facet type {0}" which will then be used as the error
if a diagnostic is produced during identification, with the latter
diagnostic attached as a note to explain why the contextual operation
failed.
In particular, this allows monomorphization errors (such as an array
bound being negative) to be attached to a higher lever operation instead
of being top-level diagnostics themselves, with the monomorphization
site being a note. This inverts the source code locations that appear in
the diagnostic, so that the top-level diagnostic points to the "user
code" which causes the monomorphization.
This is presented as an alternative strategy to #6753, which plumbed
diagnoser callbacks around to achieve the same goals.
We replace the diagnoser callbacks in type completion and operators with
ContextScope callbacks instead, which now provide better diagnostics for
monomorphization errors. Other callers to MakeSpecific do not yet have
ContextScopes introduced in order to turn monomorphization errors into
more interesting diagnostics.
63 lines
1.8 KiB
C++
63 lines
1.8 KiB
C++
// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
|
|
// Exceptions. See /LICENSE for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
|
|
#include "toolchain/diagnostics/consumer.h"
|
|
|
|
#include <algorithm>
|
|
#include <cstdint>
|
|
|
|
namespace Carbon::Diagnostics {
|
|
|
|
auto StreamConsumer::HandleDiagnostic(Diagnostic diagnostic) -> void {
|
|
if (printed_diagnostic_) {
|
|
*stream_ << "\n";
|
|
} else {
|
|
printed_diagnostic_ = true;
|
|
}
|
|
|
|
auto message_level = [&, first = true](const Message& m) mutable {
|
|
if (m.level >= Level::SoftContext && std::exchange(first, false)) {
|
|
return diagnostic.level;
|
|
}
|
|
return std::min(Level::Note, m.level);
|
|
};
|
|
for (const auto& message : diagnostic.messages) {
|
|
message.loc.FormatLocation(*stream_);
|
|
switch (message_level(message)) {
|
|
case Level::Error:
|
|
*stream_ << "error: ";
|
|
break;
|
|
case Level::Warning:
|
|
*stream_ << "warning: ";
|
|
break;
|
|
case Level::Note:
|
|
*stream_ << "note: ";
|
|
break;
|
|
case Level::LocationInfo:
|
|
break;
|
|
case Level::SoftContext:
|
|
case Level::Context:
|
|
CARBON_FATAL("Context messages are presented as a different level");
|
|
}
|
|
*stream_ << message.Format();
|
|
if (include_diagnostic_kind_) {
|
|
*stream_ << " [" << message.kind << "]";
|
|
}
|
|
*stream_ << "\n";
|
|
// Don't include a snippet for location information to keep this diagnostic
|
|
// more visually associated with the following diagnostic that it describes
|
|
// and to better match C++ compilers.
|
|
if (message.level != Level::LocationInfo) {
|
|
message.loc.FormatSnippet(*stream_);
|
|
}
|
|
}
|
|
}
|
|
|
|
auto ConsoleConsumer() -> Consumer& {
|
|
static auto* consumer = new StreamConsumer(&llvm::errs());
|
|
return *consumer;
|
|
}
|
|
|
|
} // namespace Carbon::Diagnostics
|