Files
carbon-lang/toolchain/check/testdata/alias/var.carbon
T
Chandler Carruth 2c9739799b Render diagnostics through the terminal library (#7683)
Diagnostic rendering was part of the data model: `Loc::FormatLocation`
and
`Loc::FormatSnippet` wrote plain text to a stream, so no capability,
color, or
terminal width could reach them.

A diagnostic is now one message with labels, contexts, and location
information
attached, and `Diagnostics::Renderer` draws it into a
`Terminal::Buffer`. The
design is in `toolchain/docs/diagnostics_rendering.md` (#7668),
authoring in
`toolchain/docs/diagnostics.md`.

Before:

```
example.carbon:6:3: error: 1 argument passed to function expecting 0 arguments
  Run0(1);
  ^~~~~~~
example.carbon:3:1: note: calling function declared here
fn Run0() {}
^~~~~~~~~~~
```

After:

```
error: 1 argument passed to function expecting 0 arguments
       ╭─┤ example.carbon:6:3
       ┆
     3 │ fn Run0() {}
       · ─────┬─────
       ·      ╰──┤ calling function declared here
       ┆
->   6 │   Run0(1);
       ·   ───────
       ╰────────────
```

`--no-diagnostic-snippets` gives a compact form, `example.carbon:6:3-9`.
File
tests use it; the rendering tests under `toolchain/diagnostics/testdata`
ask for
snippets.

C++ interop diagnostics are data now rather than text Clang drew:
`SemIR::ClangSourceLocId` names a `clang::SourceRange`, and a Clang
location is
marked as the point it names.

`StreamConsumer` moves to a `:renderer` target that `:emitter` does not
depend
on, keeping `common/terminal` out of `consumer.h`. Capabilities come
from the
file behind the error stream, so tests get plain ASCII.

`renderer_fuzzer` draws diagnostics built from fuzzer bytes with every
capability combination, since a shape the renderer doesn't expect must
never be
why the compiler dies while reporting a problem.

TODOs mark the follow-ups: line weights and crossing lines, wrapping
that keeps
a quoted type whole, and ordering diagnostics that share a byte offset.

Also: `IncorrectExtension`'s hint moves into its message, since its note
had no
location of its own, and `strip_noise` in `check_diagnostics.py` blanks
multi-line `#define`s instead of deleting them.

Assisted-by: Claude Code
2026-10-15 06:08:57 +00:00

78 lines
2.4 KiB
Plaintext

// 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-FILE: toolchain/testing/testdata/min_prelude/destroy.carbon
//
// AUTOUPDATE
// TIP: To test this file alone, run:
// TIP: bazel test //toolchain/testing:file_test --test_arg=--file_tests=toolchain/check/testdata/alias/var.carbon
// TIP: To dump output, run:
// TIP: bazel run //toolchain/testing:file_test -- --dump_output --file_tests=toolchain/check/testdata/alias/var.carbon
// --- global.carbon
library "[[@TEST_NAME]]";
var a: () = ();
fn F() -> () {
//@dump-sem-ir-begin
// TODO: Decide if this should be allowed, and if so, whether it should be
// spelled as
//
// alias b = ref a;
alias b = a;
//@dump-sem-ir-end
return b;
}
// --- fail_local.carbon
library "[[@TEST_NAME]]";
fn F() -> () {
var a: () = ();
//@dump-sem-ir-begin
// CHECK:STDERR: fail_local.carbon:[[@LINE+2]]:13: error: alias refers to a runtime value [AliasRequiresConstantValue]
// CHECK:STDERR:
alias b = a;
//@dump-sem-ir-end
return b;
}
// CHECK:STDOUT: --- global.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT: type: type = facet_type <type> [concrete]
// CHECK:STDOUT: %empty_tuple.type: type = tuple_type () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @F() -> out %return.param: %empty_tuple.type {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT: %a.ref: ref %empty_tuple.type = name_ref a, file.%a [concrete = file.%a.var]
// CHECK:STDOUT: %b: ref %empty_tuple.type = alias_binding b, %a.ref [concrete = file.%a.var]
// CHECK:STDOUT: <elided>
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @__global_init() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT: <elided>
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_local.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT: type: type = facet_type <type> [concrete]
// CHECK:STDOUT: %empty_tuple.type: type = tuple_type () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @F() -> out %return.param: %empty_tuple.type {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT: <elided>
// CHECK:STDOUT: %a.ref: ref %empty_tuple.type = name_ref a, %a
// CHECK:STDOUT: %b: ref %empty_tuple.type = alias_binding b, %a.ref
// CHECK:STDOUT: <elided>
// CHECK:STDOUT: }
// CHECK:STDOUT: