Debug assertion failure when error snippet has tab character

[osa1]

Generated by a simple fuzz tool I'm working on. Repro:

fn main() {
    """	"
}

(note that the second string has a tab)

Error:

thread 'rustc' panicked at 'assertion failed: self.text.iter().all(|r| !r.contains(&\'\\t\'))', compiler/rustc_errors/src/styled_buffer.rs:19:9

Backtrace:

stack backtrace:
   0: rust_begin_unwind
             at /home/omer/rust/rust/library/std/src/panicking.rs:493:5
   1: core::panicking::panic_fmt
             at /home/omer/rust/rust/library/core/src/panicking.rs:92:14
   2: core::panicking::panic
             at /home/omer/rust/rust/library/core/src/panicking.rs:50:5
   3: rustc_errors::styled_buffer::StyledBuffer::render
             at /home/omer/rust/rust/compiler/rustc_errors/src/styled_buffer.rs:19:9
   4: rustc_errors::emitter::EmitterWriter::emit_message_default
             at /home/omer/rust/rust/compiler/rustc_errors/src/emitter.rs:1537:30
   5: rustc_errors::emitter::EmitterWriter::emit_messages_default
             at /home/omer/rust/rust/compiler/rustc_errors/src/emitter.rs:1715:15
   6: <rustc_errors::emitter::EmitterWriter as rustc_errors::emitter::Emitter>::emit_diagnostic
             at /home/omer/rust/rust/compiler/rustc_errors/src/emitter.rs:496:9
   7: rustc_errors::HandlerInner::emit_diagnostic
             at /home/omer/rust/rust/compiler/rustc_errors/src/lib.rs:828:13
   8: rustc_errors::Handler::emit_diagnostic
             at /home/omer/rust/rust/compiler/rustc_errors/src/lib.rs:756:9
   9: rustc_errors::diagnostic_builder::DiagnosticBuilder::emit
             at /home/omer/rust/rust/compiler/rustc_errors/src/diagnostic_builder.rs:103:9
  10: rustc_parse::parser::stmt::<impl rustc_parse::parser::Parser>::parse_full_stmt
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/stmt.rs:481:25
  11: rustc_parse::parser::stmt::<impl rustc_parse::parser::Parser>::parse_block_tail
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/stmt.rs:415:30
  12: rustc_parse::parser::stmt::<impl rustc_parse::parser::Parser>::parse_block_common
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/stmt.rs:397:13
  13: rustc_parse::parser::stmt::<impl rustc_parse::parser::Parser>::parse_inner_attrs_and_block
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/stmt.rs:378:9
  14: rustc_parse::parser::item::<impl rustc_parse::parser::Parser>::parse_fn_body
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/item.rs:1600:13
  15: rustc_parse::parser::item::<impl rustc_parse::parser::Parser>::parse_fn
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/item.rs:1581:20
  16: rustc_parse::parser::item::<impl rustc_parse::parser::Parser>::parse_item_kind
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/item.rs:232:48
  17: rustc_parse::parser::item::<impl rustc_parse::parser::Parser>::parse_item_common_
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/item.rs:145:20
  18: rustc_parse::parser::item::<impl rustc_parse::parser::Parser>::parse_item_common::{{closure}}
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/item.rs:126:28
  19: rustc_parse::parser::attr_wrapper::<impl rustc_parse::parser::Parser>::collect_tokens_trailing_token
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/attr_wrapper.rs:69:23
  20: rustc_parse::parser::item::<impl rustc_parse::parser::Parser>::parse_item_common
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/item.rs:125:13
  21: rustc_parse::parser::item::<impl rustc_parse::parser::Parser>::parse_item_
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/item.rs:91:9
  22: rustc_parse::parser::item::<impl rustc_parse::parser::Parser>::parse_item
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/item.rs:82:9
  23: rustc_parse::parser::item::<impl rustc_parse::parser::Parser>::parse_mod
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/item.rs:59:32
  24: rustc_parse::parser::item::<impl rustc_parse::parser::Parser>::parse_crate_mod
             at /home/omer/rust/rust/compiler/rustc_parse/src/parser/item.rs:28:36
  25: rustc_parse::parse_crate_from_file
             at /home/omer/rust/rust/compiler/rustc_parse/src/lib.rs:58:5
  26: rustc_interface::passes::parse::{{closure}}
             at /home/omer/rust/rust/compiler/rustc_interface/src/passes.rs:58:30
  27: rustc_data_structures::profiling::VerboseTimingGuard::run
             at /home/omer/rust/rust/compiler/rustc_data_structures/src/profiling.rs:573:9
  28: rustc_session::utils::<impl rustc_session::session::Session>::time
             at /home/omer/rust/rust/compiler/rustc_session/src/utils.rs:10:9
  29: rustc_interface::passes::parse
             at /home/omer/rust/rust/compiler/rustc_interface/src/passes.rs:57:17
  30: rustc_interface::queries::Queries::parse::{{closure}}
             at /home/omer/rust/rust/compiler/rustc_interface/src/queries.rs:132:13
  31: rustc_interface::queries::Query<T>::compute
             at /home/omer/rust/rust/compiler/rustc_interface/src/queries.rs:40:28
  32: rustc_interface::queries::Queries::parse
             at /home/omer/rust/rust/compiler/rustc_interface/src/queries.rs:131:9
  33: rustc_driver::run_compiler::{{closure}}::{{closure}}
             at /home/omer/rust/rust/compiler/rustc_driver/src/lib.rs:336:13
  34: rustc_interface::queries::<impl rustc_interface::interface::Compiler>::enter
             at /home/omer/rust/rust/compiler/rustc_interface/src/queries.rs:422:19
  35: rustc_driver::run_compiler::{{closure}}
             at /home/omer/rust/rust/compiler/rustc_driver/src/lib.rs:334:22
  36: rustc_interface::interface::create_compiler_and_run::{{closure}}
             at /home/omer/rust/rust/compiler/rustc_interface/src/interface.rs:208:13
  37: rustc_span::with_source_map
             at /home/omer/rust/rust/compiler/rustc_span/src/lib.rs:788:5
  38: rustc_interface::interface::create_compiler_and_run
             at /home/omer/rust/rust/compiler/rustc_interface/src/interface.rs:202:5
  39: rustc_interface::interface::run_compiler::{{closure}}
             at /home/omer/rust/rust/compiler/rustc_interface/src/interface.rs:224:12
  40: rustc_interface::util::setup_callbacks_and_run_in_thread_pool_with_globals::{{closure}}::{{closure}}
             at /home/omer/rust/rust/compiler/rustc_interface/src/util.rs:155:13
  41: scoped_tls::ScopedKey<T>::set
             at /home/omer/.cargo/registry/src/github.com-1ecc6299db9ec823/scoped-tls-1.0.0/src/lib.rs:137:9
  42: rustc_span::with_session_globals
             at /home/omer/rust/rust/compiler/rustc_span/src/lib.rs:105:5
  43: rustc_interface::util::setup_callbacks_and_run_in_thread_pool_with_globals::{{closure}}
             at /home/omer/rust/rust/compiler/rustc_interface/src/util.rs:153:9
  44: rustc_interface::util::scoped_thread::{{closure}}
             at /home/omer/rust/rust/compiler/rustc_interface/src/util.rs:128:24
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

@rustbot claim