diff options
Diffstat (limited to 'compiler/rustc_errors/src')
| -rw-r--r-- | compiler/rustc_errors/src/diagnostic.rs | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/compiler/rustc_errors/src/diagnostic.rs b/compiler/rustc_errors/src/diagnostic.rs index 797dcd7b4d1..b96df814852 100644 --- a/compiler/rustc_errors/src/diagnostic.rs +++ b/compiler/rustc_errors/src/diagnostic.rs @@ -4,6 +4,7 @@ use std::hash::{Hash, Hasher}; use std::marker::PhantomData; use std::ops::{Deref, DerefMut}; use std::panic; +use std::path::PathBuf; use std::thread::panicking; use rustc_data_structures::fx::FxIndexMap; @@ -301,6 +302,7 @@ pub struct DiagInner { pub is_lint: Option<IsLint>, + pub long_ty_path: Option<PathBuf>, /// With `-Ztrack_diagnostics` enabled, /// we print where in rustc this error was emitted. pub(crate) emitted_at: DiagLocation, @@ -324,6 +326,7 @@ impl DiagInner { args: Default::default(), sort_span: DUMMY_SP, is_lint: None, + long_ty_path: None, emitted_at: DiagLocation::caller(), } } @@ -1293,9 +1296,37 @@ impl<'a, G: EmissionGuarantee> Diag<'a, G> { /// `cancel`, etc. Afterwards, `drop` is the only code that will be run on /// `self`. fn take_diag(&mut self) -> DiagInner { + if let Some(path) = &self.long_ty_path { + self.note(format!( + "the full name for the type has been written to '{}'", + path.display() + )); + self.note("consider using `--verbose` to print the full type name to the console"); + } Box::into_inner(self.diag.take().unwrap()) } + /// This method allows us to access the path of the file where "long types" are written to. + /// + /// When calling `Diag::emit`, as part of that we will check if a `long_ty_path` has been set, + /// and if it has been then we add a note mentioning the file where the "long types" were + /// written to. + /// + /// When calling `tcx.short_string()` after a `Diag` is constructed, the preferred way of doing + /// so is `tcx.short_string(ty, diag.long_ty_path())`. The diagnostic itself is the one that + /// keeps the existence of a "long type" anywhere in the diagnostic, so the note telling the + /// user where we wrote the file to is only printed once at most, *and* it makes it much harder + /// to forget to set it. + /// + /// If the diagnostic hasn't been created before a "short ty string" is created, then you should + /// ensure that this method is called to set it `*diag.long_ty_path() = path`. + /// + /// As a rule of thumb, if you see or add at least one `tcx.short_string()` call anywhere, in a + /// scope, `diag.long_ty_path()` should be called once somewhere close by. + pub fn long_ty_path(&mut self) -> &mut Option<PathBuf> { + &mut self.long_ty_path + } + /// Most `emit_producing_guarantee` functions use this as a starting point. fn emit_producing_nothing(mut self) { let diag = self.take_diag(); |