From 454e2aa8c99850c9393fb2314e1a71da08120063 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Esteban=20K=C3=BCber?= Date: Mon, 28 Oct 2019 17:44:20 -0700 Subject: [PATCH] Do not complain about missing `fn main()` in some cases --- src/librustc_metadata/cstore_impl.rs | 2 +- src/librustc_passes/entry.rs | 9 +++++- src/libsyntax/parse/mod.rs | 4 +-- src/libsyntax/parse/parser.rs | 13 +++++---- src/libsyntax/parse/parser/diagnostics.rs | 5 ++++ src/libsyntax/sess.rs | 3 ++ src/test/ui/parser-recovery-1.rs | 1 - src/test/ui/parser-recovery-1.stderr | 26 ++++------------- src/test/ui/parser/issue-2354.rs | 7 ++--- src/test/ui/parser/issue-2354.stderr | 28 ++----------------- .../missing-close-brace-in-impl-trait.rs | 3 +- .../missing-close-brace-in-impl-trait.stderr | 25 ++++------------- .../missing-close-brace-in-struct.rs | 2 +- .../missing-close-brace-in-struct.stderr | 15 +--------- .../missing-close-brace-in-trait.rs | 1 - .../missing-close-brace-in-trait.stderr | 22 +++------------ 16 files changed, 50 insertions(+), 116 deletions(-) diff --git a/src/librustc_metadata/cstore_impl.rs b/src/librustc_metadata/cstore_impl.rs index d942a19194a14..cdf5da006064a 100644 --- a/src/librustc_metadata/cstore_impl.rs +++ b/src/librustc_metadata/cstore_impl.rs @@ -440,7 +440,7 @@ impl cstore::CStore { let source_file = sess.parse_sess.source_map().new_source_file(source_name, def.body); let local_span = Span::with_root_ctxt(source_file.start_pos, source_file.end_pos); let (body, mut errors) = source_file_to_stream(&sess.parse_sess, source_file, None); - emit_unclosed_delims(&mut errors, &sess.diagnostic()); + emit_unclosed_delims(&mut errors, &sess.parse_sess); // Mark the attrs as used let attrs = data.get_item_attrs(id.index, sess); diff --git a/src/librustc_passes/entry.rs b/src/librustc_passes/entry.rs index bf68807a0c29b..660047190608d 100644 --- a/src/librustc_passes/entry.rs +++ b/src/librustc_passes/entry.rs @@ -154,6 +154,14 @@ fn configure_main(tcx: TyCtxt<'_>, visitor: &EntryContext<'_, '_>) -> Option<(De } fn no_main_err(tcx: TyCtxt<'_>, visitor: &EntryContext<'_, '_>) { + let sp = tcx.hir().krate().span; + if *tcx.sess.parse_sess.reached_eof.borrow() { + // There's an unclosed brace that made the parser reach `Eof`, we shouldn't complain about + // the missing `fn main()` then as it might have been hidden inside an unclosed block. + tcx.sess.delay_span_bug(sp, "`main` not found, but expected unclosed brace error"); + return; + } + // There is no main function. let mut err = struct_err!(tcx.sess, E0601, "`main` function not found in crate `{}`", tcx.crate_name(LOCAL_CRATE)); @@ -173,7 +181,6 @@ fn no_main_err(tcx: TyCtxt<'_>, visitor: &EntryContext<'_, '_>) { } else { String::from("consider adding a `main` function at the crate level") }; - let sp = tcx.hir().krate().span; // The file may be empty, which leads to the diagnostic machinery not emitting this // note. This is a relatively simple way to detect that case and emit a span-less // note instead. diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs index 921c4ed0f0ad3..6d8ecdf805b01 100644 --- a/src/libsyntax/parse/mod.rs +++ b/src/libsyntax/parse/mod.rs @@ -108,7 +108,7 @@ pub fn parse_stream_from_source_str( sess.source_map().new_source_file(name, source), override_span, ); - emit_unclosed_delims(&mut errors, &sess.span_diagnostic); + emit_unclosed_delims(&mut errors, &sess); stream } @@ -242,7 +242,7 @@ pub fn maybe_file_to_stream( err.buffer(&mut buffer); // Not using `emit_unclosed_delims` to use `db.buffer` for unmatched in unmatched_braces { - if let Some(err) = make_unclosed_delims_error(unmatched, &sess.span_diagnostic) { + if let Some(err) = make_unclosed_delims_error(unmatched, &sess) { err.buffer(&mut buffer); } } diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs index 5dbe4d95a85d6..e81d4573b73e5 100644 --- a/src/libsyntax/parse/parser.rs +++ b/src/libsyntax/parse/parser.rs @@ -148,8 +148,7 @@ pub struct Parser<'a> { impl<'a> Drop for Parser<'a> { fn drop(&mut self) { - let diag = self.diagnostic(); - emit_unclosed_delims(&mut self.unclosed_delims, diag); + emit_unclosed_delims(&mut self.unclosed_delims, &self.sess); } } @@ -1372,12 +1371,12 @@ impl<'a> Parser<'a> { crate fn make_unclosed_delims_error( unmatched: UnmatchedBrace, - handler: &errors::Handler, + sess: &ParseSess, ) -> Option> { // `None` here means an `Eof` was found. We already emit those errors elsewhere, we add them to // `unmatched_braces` only for error recovery in the `Parser`. let found_delim = unmatched.found_delim?; - let mut err = handler.struct_span_err(unmatched.found_span, &format!( + let mut err = sess.span_diagnostic.struct_span_err(unmatched.found_span, &format!( "incorrect close delimiter: `{}`", pprust::token_kind_to_string(&token::CloseDelim(found_delim)), )); @@ -1391,8 +1390,10 @@ crate fn make_unclosed_delims_error( Some(err) } -pub fn emit_unclosed_delims(unclosed_delims: &mut Vec, handler: &errors::Handler) { +pub fn emit_unclosed_delims(unclosed_delims: &mut Vec, sess: &ParseSess) { + *sess.reached_eof.borrow_mut() |= unclosed_delims.iter() + .any(|unmatched_delim| unmatched_delim.found_delim.is_none()); for unmatched in unclosed_delims.drain(..) { - make_unclosed_delims_error(unmatched, handler).map(|mut e| e.emit()); + make_unclosed_delims_error(unmatched, sess).map(|mut e| e.emit()); } } diff --git a/src/libsyntax/parse/parser/diagnostics.rs b/src/libsyntax/parse/parser/diagnostics.rs index be1441d1c3f80..fcf3b4c0aa891 100644 --- a/src/libsyntax/parse/parser/diagnostics.rs +++ b/src/libsyntax/parse/parser/diagnostics.rs @@ -1141,6 +1141,11 @@ impl<'a> Parser<'a> { // Don't attempt to recover from this unclosed delimiter more than once. let unmatched = self.unclosed_delims.remove(pos); let delim = TokenType::Token(token::CloseDelim(unmatched.expected_delim)); + if unmatched.found_delim.is_none() { + // We encountered `Eof`, set this fact here to avoid complaining about missing + // `fn main()` when we found place to suggest the closing brace. + *self.sess.reached_eof.borrow_mut() = true; + } // We want to suggest the inclusion of the closing delimiter where it makes // the most sense, which is immediately after the last token: diff --git a/src/libsyntax/sess.rs b/src/libsyntax/sess.rs index 28a0868d5dd1e..323fe01f067ef 100644 --- a/src/libsyntax/sess.rs +++ b/src/libsyntax/sess.rs @@ -73,6 +73,8 @@ pub struct ParseSess { pub ambiguous_block_expr_parse: Lock>, pub injected_crate_name: Once, crate gated_spans: GatedSpans, + /// The parser has reached `Eof` due to an unclosed brace. Used to silence unnecessary errors. + pub reached_eof: Lock, } impl ParseSess { @@ -101,6 +103,7 @@ impl ParseSess { ambiguous_block_expr_parse: Lock::new(FxHashMap::default()), injected_crate_name: Once::new(), gated_spans: GatedSpans::default(), + reached_eof: Lock::new(false), } } diff --git a/src/test/ui/parser-recovery-1.rs b/src/test/ui/parser-recovery-1.rs index 8126525c34f95..21d36048e6703 100644 --- a/src/test/ui/parser-recovery-1.rs +++ b/src/test/ui/parser-recovery-1.rs @@ -3,7 +3,6 @@ // Test that we can recover from missing braces in the parser. trait Foo { -//~^ ERROR `main` function not found fn bar() { let x = foo(); //~^ ERROR cannot find function `foo` in this scope diff --git a/src/test/ui/parser-recovery-1.stderr b/src/test/ui/parser-recovery-1.stderr index ffe2b3322fc81..83f8ef63c9954 100644 --- a/src/test/ui/parser-recovery-1.stderr +++ b/src/test/ui/parser-recovery-1.stderr @@ -1,9 +1,8 @@ error: this file contains an un-closed delimiter - --> $DIR/parser-recovery-1.rs:16:55 + --> $DIR/parser-recovery-1.rs:15:55 | LL | trait Foo { | - un-closed delimiter -LL | LL | fn bar() { | - this delimiter might not be properly closed... ... @@ -14,36 +13,23 @@ LL | } | ^ error: unexpected token: `;` - --> $DIR/parser-recovery-1.rs:13:15 + --> $DIR/parser-recovery-1.rs:12:15 | LL | let x = y.; | ^ error[E0425]: cannot find function `foo` in this scope - --> $DIR/parser-recovery-1.rs:8:17 + --> $DIR/parser-recovery-1.rs:7:17 | LL | let x = foo(); | ^^^ not found in this scope error[E0425]: cannot find value `y` in this scope - --> $DIR/parser-recovery-1.rs:13:13 + --> $DIR/parser-recovery-1.rs:12:13 | LL | let x = y.; | ^ not found in this scope -error[E0601]: `main` function not found in crate `parser_recovery_1` - --> $DIR/parser-recovery-1.rs:5:1 - | -LL | / trait Foo { -LL | | -LL | | fn bar() { -LL | | let x = foo(); -... | -LL | | -LL | | } - | |______________________________________________________^ consider adding a `main` function to `$DIR/parser-recovery-1.rs` - -error: aborting due to 5 previous errors +error: aborting due to 4 previous errors -Some errors have detailed explanations: E0425, E0601. -For more information about an error, try `rustc --explain E0425`. +For more information about this error, try `rustc --explain E0425`. diff --git a/src/test/ui/parser/issue-2354.rs b/src/test/ui/parser/issue-2354.rs index a14eb6e32fc91..c4fc471618283 100644 --- a/src/test/ui/parser/issue-2354.rs +++ b/src/test/ui/parser/issue-2354.rs @@ -1,7 +1,4 @@ fn foo() { //~ NOTE un-closed delimiter -//~^ ERROR `main` function not found -//~^^ NOTE main function must be defined -//~^^^ NOTE you have one or more functions match Some(10) { //~^ NOTE this delimiter might not be properly closed... Some(y) => { panic!(); } @@ -14,5 +11,5 @@ fn bar() { while (i < 1000) {} } -fn main() {} //~ NOTE here is a function named `main` - //~ ERROR this file contains an un-closed delimiter +fn main() {} +//~ ERROR this file contains an un-closed delimiter diff --git a/src/test/ui/parser/issue-2354.stderr b/src/test/ui/parser/issue-2354.stderr index 038e3dcfa40a9..45199b02cb8d4 100644 --- a/src/test/ui/parser/issue-2354.stderr +++ b/src/test/ui/parser/issue-2354.stderr @@ -1,9 +1,8 @@ error: this file contains an un-closed delimiter - --> $DIR/issue-2354.rs:18:66 + --> $DIR/issue-2354.rs:15:53 | LL | fn foo() { | - un-closed delimiter -... LL | match Some(10) { | - this delimiter might not be properly closed... ... @@ -11,28 +10,7 @@ LL | } | - ...as it matches this but it has different indentation ... LL | - | ^ - -error[E0601]: `main` function not found in crate `issue_2354` - --> $DIR/issue-2354.rs:1:1 - | -LL | / fn foo() { -LL | | -LL | | -LL | | -... | -LL | | fn main() {} -LL | | - | |_________________________________________________________________^ the main function must be defined at the crate level (in `$DIR/issue-2354.rs`) - | -note: here is a function named `main` - --> $DIR/issue-2354.rs:17:1 - | -LL | fn main() {} - | ^^^^^^^^^^^^ - = note: you have one or more functions named `main` not defined at the crate level - = help: either move the `main` function definitions or attach the `#[main]` attribute to one of them + | ^ -error: aborting due to 2 previous errors +error: aborting due to previous error -For more information about this error, try `rustc --explain E0601`. diff --git a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-impl-trait.rs b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-impl-trait.rs index 66f43889cec1c..8d89905909e94 100644 --- a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-impl-trait.rs +++ b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-impl-trait.rs @@ -1,5 +1,4 @@ -impl T for () { //~ ERROR `main` function not found -//~^ ERROR cannot find trait `T` in this scope +impl T for () { //~ ERROR cannot find trait `T` in this scope fn foo(&self) {} diff --git a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-impl-trait.stderr b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-impl-trait.stderr index 52c00758b3722..9bf54181a079c 100644 --- a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-impl-trait.stderr +++ b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-impl-trait.stderr @@ -1,5 +1,5 @@ error: this file contains an un-closed delimiter - --> $DIR/missing-close-brace-in-impl-trait.rs:13:53 + --> $DIR/missing-close-brace-in-impl-trait.rs:12:53 | LL | impl T for () { | - un-closed delimiter @@ -7,12 +7,12 @@ LL | impl T for () { LL | | ^ -error: expected one of `async`, `const`, `crate`, `default`, `extern`, `fn`, `pub`, `type`, `unsafe`, or `}`, found `trait` - --> $DIR/missing-close-brace-in-impl-trait.rs:6:1 +error: expected one of `async`, `const`, `crate`, `default`, `extern`, `fn`, `pub`, `type`, `unsafe`, or `}`, found keyword `trait` + --> $DIR/missing-close-brace-in-impl-trait.rs:5:1 | LL | impl T for () { | - unclosed delimiter -... +LL | LL | fn foo(&self) {} | - | | @@ -28,19 +28,6 @@ error[E0405]: cannot find trait `T` in this scope LL | impl T for () { | ^ not found in this scope -error[E0601]: `main` function not found in crate `missing_close_brace_in_impl_trait` - --> $DIR/missing-close-brace-in-impl-trait.rs:1:1 - | -LL | / impl T for () { -LL | | -LL | | -LL | | fn foo(&self) {} -... | -LL | | fn main() {} -LL | | - | |____________________________________________________^ consider adding a `main` function to `$DIR/missing-close-brace-in-impl-trait.rs` - -error: aborting due to 4 previous errors +error: aborting due to 3 previous errors -Some errors have detailed explanations: E0405, E0601. -For more information about an error, try `rustc --explain E0405`. +For more information about this error, try `rustc --explain E0405`. diff --git a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-struct.rs b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-struct.rs index 8f42897914ac5..5b716b1467cb1 100644 --- a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-struct.rs +++ b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-struct.rs @@ -1,4 +1,4 @@ -pub(crate) struct Bar { //~ ERROR `main` function not found +pub(crate) struct Bar { foo: T, trait T { //~ ERROR expected identifier, found keyword `trait` diff --git a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-struct.stderr b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-struct.stderr index e0d5eb90aa1cc..ce399dbbf456d 100644 --- a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-struct.stderr +++ b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-struct.stderr @@ -24,18 +24,5 @@ error: expected `:`, found `T` LL | trait T { | ^ expected `:` -error[E0601]: `main` function not found in crate `missing_close_brace_in_struct` - --> $DIR/missing-close-brace-in-struct.rs:1:1 - | -LL | / pub(crate) struct Bar { -LL | | foo: T, -LL | | -LL | | trait T { -... | -LL | | -LL | | fn main() {} - | |_________________________________________________________________^ consider adding a `main` function to `$DIR/missing-close-brace-in-struct.rs` - -error: aborting due to 4 previous errors +error: aborting due to 3 previous errors -For more information about this error, try `rustc --explain E0601`. diff --git a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-trait.rs b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-trait.rs index 46b9cab66e967..7954719541127 100644 --- a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-trait.rs +++ b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-trait.rs @@ -1,5 +1,4 @@ trait T { -//~^ ERROR `main` function not found in crate `missing_close_brace_in_trait` fn foo(&self); pub(crate) struct Bar(); //~ ERROR expected one of diff --git a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-trait.stderr b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-trait.stderr index 7de6c1d0cdd95..4bfb4c1cb3a52 100644 --- a/src/test/ui/parser/mismatched-braces/missing-close-brace-in-trait.stderr +++ b/src/test/ui/parser/mismatched-braces/missing-close-brace-in-trait.stderr @@ -1,5 +1,5 @@ error: this file contains an un-closed delimiter - --> $DIR/missing-close-brace-in-trait.rs:11:66 + --> $DIR/missing-close-brace-in-trait.rs:10:66 | LL | trait T { | - un-closed delimiter @@ -7,12 +7,11 @@ LL | trait T { LL | fn main() {} | ^ -error: expected one of `async`, `const`, `extern`, `fn`, `type`, `unsafe`, or `}`, found `pub` - --> $DIR/missing-close-brace-in-trait.rs:5:1 +error: expected one of `async`, `const`, `extern`, `fn`, `type`, `unsafe`, or `}`, found keyword `pub` + --> $DIR/missing-close-brace-in-trait.rs:4:1 | LL | trait T { | - unclosed delimiter -LL | LL | fn foo(&self); | - | | @@ -22,18 +21,5 @@ LL | LL | pub(crate) struct Bar(); | ^^^ unexpected token -error[E0601]: `main` function not found in crate `missing_close_brace_in_trait` - --> $DIR/missing-close-brace-in-trait.rs:1:1 - | -LL | / trait T { -LL | | -LL | | fn foo(&self); -LL | | -... | -LL | | -LL | | fn main() {} - | |_________________________________________________________________^ consider adding a `main` function to `$DIR/missing-close-brace-in-trait.rs` - -error: aborting due to 3 previous errors +error: aborting due to 2 previous errors -For more information about this error, try `rustc --explain E0601`.