No errors / warnings are reported by extension when async-std with attributes feature is used

[Gozala]

Here is a minimal reproducible test case I've created to illustrate the issue. Running cargo check reports issues as expected:

cargo check
    Checking adder v0.1.0 (/Users/gozala/Projects/rls-vscode-bug-report/adder)
error: cannot find macro `println2` in this scope
  --> adder/src/main.rs:2:5
   |
2  |       println2!("Hello, world!");
   |       ^^^^^^^^ help: a macro with a similar name exists: `println`

error: aborting due to previous error

error: could not compile `adder`.

To learn more, run the command again with --verbose.

Plugin however does not display this error, instead it reports error in
Cargo.toml.

VSCode settings are included in the repo .vscode/settings.json.

Including additional setup information:

rustup show
Default host: x86_64-apple-darwin
rustup home:  /Users/gozala/.rustup

installed toolchains
--------------------

stable-x86_64-apple-darwin
nightly-x86_64-apple-darwin (default)

active toolchain
----------------

nightly-x86_64-apple-darwin (default)
rustc 1.44.0-nightly (f509b26a7 2020-03-18)

[Gozala]

I have enable set "rust-client.trace.server": "messages" and did see following errors in output

[Trace - 1:17:01 PM] Sending request 'textDocument/codeAction - (12)'.
[Trace - 1:17:01 PM] Sending request 'textDocument/documentSymbol - (13)'.
[Trace - 1:17:01 PM] Received response 'textDocument/codeAction - (12)' in 10ms.
[Trace - 1:17:01 PM] Received response 'textDocument/documentSymbol - (13)' in 21ms.
[Trace - 1:17:01 PM] Sending request 'textDocument/codeLens - (14)'.
[Trace - 1:17:01 PM] Received response 'textDocument/codeLens - (14)' in 5ms.
[Trace - 1:17:02 PM] Sending request 'textDocument/formatting - (15)'.
[Trace - 1:17:02 PM] Received response 'textDocument/formatting - (15)' in 4ms.
[Trace - 1:17:02 PM] Sending notification 'textDocument/didSave'.
[Trace - 1:17:02 PM] Sending request 'textDocument/codeLens - (16)'.
[Trace - 1:17:02 PM] Received response 'textDocument/codeLens - (16)' in 6ms.
[Trace - 1:17:11 PM] Sending request 'textDocument/codeAction - (17)'.
[Trace - 1:17:11 PM] Sending request 'textDocument/documentSymbol - (18)'.
[Trace - 1:17:11 PM] Received response 'textDocument/codeAction - (17)' in 9ms.
[Trace - 1:17:11 PM] Received response 'textDocument/documentSymbol - (18)' in 7ms.
[Trace - 1:17:11 PM] Sending request 'textDocument/codeLens - (19)'.
[Trace - 1:17:11 PM] Received response 'textDocument/codeLens - (19)' in 2ms.
[Trace - 1:17:12 PM] Sending request 'textDocument/documentHighlight - (20)'.
[Trace - 1:17:12 PM] Received response 'textDocument/documentHighlight - (20)' in 3ms.
[Trace - 1:17:12 PM] Sending request 'textDocument/codeAction - (21)'.
[Trace - 1:17:12 PM] Received response 'textDocument/codeAction - (21)' in 0ms.
[Trace - 1:17:12 PM] Sending request 'textDocument/hover - (22)'.
[Trace - 1:17:12 PM] Received response 'textDocument/hover - (22)' in 2ms.
[Trace - 1:17:13 PM] Sending request 'textDocument/documentHighlight - (23)'.
[Trace - 1:17:13 PM] Received response 'textDocument/documentHighlight - (23)' in 11ms.
[Trace - 1:17:13 PM] Sending request 'textDocument/codeAction - (24)'.
[Trace - 1:17:13 PM] Received response 'textDocument/codeAction - (24)' in 1ms.
[Trace - 1:17:14 PM] Sending notification 'textDocument/didChange'.
[Trace - 1:17:14 PM] Received notification 'window/progress'.
[Trace - 1:17:14 PM] Received notification 'window/progress'.
[Trace - 1:17:14 PM] Sending request 'textDocument/codeLens - (25)'.
[Trace - 1:17:14 PM] Received response 'textDocument/codeLens - (25)' in 1ms.
[Trace - 1:17:14 PM] Sending request 'textDocument/codeAction - (26)'.
[Trace - 1:17:14 PM] Sending request 'textDocument/documentSymbol - (27)'.
[Trace - 1:17:14 PM] Received response 'textDocument/codeAction - (26)' in 3ms.
[Trace - 1:17:14 PM] Received response 'textDocument/documentSymbol - (27)' in 5ms.
[Trace - 1:17:14 PM] Sending request 'textDocument/formatting - (28)'.
[Trace - 1:17:14 PM] Received response 'textDocument/formatting - (28)' in 1ms.
[Trace - 1:17:14 PM] Sending notification 'textDocument/didSave'.
{"message":"cannot lex `source_file` without source: /Users/gozala/.cargo/registry/src/github.com-1ecc6299db9ec823/quote-1.0.3/src/lib.rs","code":null,"level":"error: internal compiler error","spans":[],"children":[],"rendered":"\u001b[0m\u001b[1m\u001b[38;5;9merror: internal compiler error\u001b[0m\u001b[0m\u001b[1m: cannot lex `source_file` without source: /Users/gozala/.cargo/registry/src/github.com-1ecc6299db9ec823/quote-1.0.3/src/lib.rs\u001b[0m\n\n"}
thread 'rustc' panicked at 'Box<Any>', src/librustc_errors/lib.rs:880:9
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

note: the compiler unexpectedly panicked. this is a bug.

note: we would appreciate a bug report: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#bug-reports

note: rustc 1.44.0-nightly (f509b26a7 2020-03-18) running on x86_64-apple-darwin

note: compiler flags: -C prefer-dynamic -C debuginfo=2 --crate-type proc-macro

note: some of the compiler flags provided by cargo are hidden

{"message":"aborting due to previous error","code":null,"level":"error","spans":[],"children":[],"rendered":"\u001b[0m\u001b[1m\u001b[38;5;9merror\u001b[0m\u001b[0m\u001b[1m: aborting due to previous error\u001b[0m\n\n"}
[Trace - 1:17:14 PM] Received notification 'window/progress'.
[Trace - 1:17:14 PM] Received notification 'window/progress'.
[Trace - 1:17:14 PM] Received notification 'textDocument/publishDiagnostics'.
[Trace - 1:17:14 PM] Received notification 'window/progress'.
[Trace - 1:17:15 PM] Sending request 'textDocument/codeLens - (29)'.
[Trace - 1:17:15 PM] Received response 'textDocument/codeLens - (29)' in 8ms.

[Gozala]

If I do run Rust: cargo check task from the vscode then I do see error being picked up. But than again fixing that error or any changes really are not picked up unless I re-run the task.

[Gozala]

It also appears that actual issue is async-attributes crate not the async-std, in other words changing dependencies to async-attributes = "1.1.1" exhibits same problem.

[Gozala]

I found a way to reproduce this without vscode plugin that is:

RUSTFLAGS="-Z save-analysis" RUST_BACKTRACE=1 cargo check --verbose
       Fresh unicode-xid v0.2.0
       Fresh proc-macro2 v1.0.10
       Fresh quote v1.0.3
       Fresh syn v1.0.17
   Compiling async-attributes v1.1.1
     Running `rustc --crate-name async_attributes --edition=2018 /Users/gozala/.cargo/registry/src/github.com-1ecc6299db9ec823/async-attributes-1.1.1/src/lib.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type proc-macro --emit=dep-info,link -C prefer-dynamic -C debuginfo=2 -C metadata=8af7ea4b736f4259 -C extra-filename=-8af7ea4b736f4259 --out-dir /Users/gozala/Projects/ws-rs/target/debug/deps -L dependency=/Users/gozala/Projects/ws-rs/target/debug/deps --extern quote=/Users/gozala/Projects/ws-rs/target/debug/deps/libquote-b294abe5359d6464.rlib --extern syn=/Users/gozala/Projects/ws-rs/target/debug/deps/libsyn-5f2ec3f0dc10fbfc.rlib --extern proc_macro --cap-lints allow -Z save-analysis`
error: internal compiler error: cannot lex `source_file` without source: /Users/gozala/.cargo/registry/src/github.com-1ecc6299db9ec823/quote-1.0.3/src/lib.rs

thread 'rustc' panicked at 'Box<Any>', src/librustc_errors/lib.rs:880:9
stack backtrace:
   0: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
   1: core::fmt::write
   2: std::io::Write::write_fmt
   3: std::panicking::default_hook::{{closure}}
   4: std::panicking::default_hook
   5: rustc_driver::report_ice
   6: std::panicking::rust_panic_with_hook
   7: std::panicking::begin_panic
   8: rustc_errors::HandlerInner::bug
   9: rustc_errors::Handler::bug
  10: rustc_parse::lexer::StringReader::new
  11: rustc_parse::lexer::StringReader::retokenize
  12: rustc_save_analysis::span_utils::SpanUtils::sub_span_of_token
  13: rustc_save_analysis::dump_visitor::DumpVisitor::process_use_tree
  14: <rustc_save_analysis::dump_visitor::DumpVisitor as rustc_ast::visit::Visitor>::visit_item
  15: rustc_ast::visit::walk_expr
  16: rustc_ast::visit::walk_expr
  17: rustc_ast::visit::walk_expr
  18: rustc_ast::visit::walk_expr
  19: <rustc_save_analysis::dump_visitor::DumpVisitor as rustc_ast::visit::Visitor>::visit_expr
  20: rustc_ast::visit::walk_expr
  21: <rustc_save_analysis::dump_visitor::DumpVisitor as rustc_ast::visit::Visitor>::visit_item
  22: <rustc_save_analysis::dump_visitor::DumpVisitor as rustc_ast::visit::Visitor>::visit_mod
  23: rustc_ast::visit::walk_crate
  24: rustc::dep_graph::graph::DepGraph::with_ignore
  25: rustc_session::utils::<impl rustc_session::session::Session>::time
  26: rustc::ty::context::tls::enter_global
  27: rustc_interface::interface::run_compiler_in_existing_thread_pool
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

note: the compiler unexpectedly panicked. this is a bug.

note: we would appreciate a bug report: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#bug-reports

note: rustc 1.44.0-nightly (f509b26a7 2020-03-18) running on x86_64-apple-darwin

note: compiler flags: -Z save-analysis -C prefer-dynamic -C debuginfo=2 --crate-type proc-macro

note: some of the compiler flags provided by cargo are hidden

query stack during panic:
end of query stack
error: aborting due to previous error

error: could not compile `async-attributes`.

Caused by:
  process didn't exit successfully: `rustc --crate-name async_attributes --edition=2018 /Users/gozala/.cargo/registry/src/github.com-1ecc6299db9ec823/async-attributes-1.1.1/src/lib.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type proc-macro --emit=dep-info,link -C prefer-dynamic -C debuginfo=2 -C metadata=8af7ea4b736f4259 -C extra-filename=-8af7ea4b736f4259 --out-dir /Users/gozala/Projects/ws-rs/target/debug/deps -L dependency=/Users/gozala/Projects/ws-rs/target/debug/deps --extern quote=/Users/gozala/Projects/ws-rs/target/debug/deps/libquote-b294abe5359d6464.rlib --extern syn=/Users/gozala/Projects/ws-rs/target/debug/deps/libsyn-5f2ec3f0dc10fbfc.rlib --extern proc_macro --cap-lints allow -Z save-analysis` (exit code: 101)

[Gozala]

Discovered rust-lang/rust#69933 that seems related. It appears fixed, however downgrading to nightly-2020-03-09 as per discussion there seems to resolve issue on my end.