Auto merge of #69926 - RoccoDev:master, r=estebank,varkor

rustc: Add a warning count upon completion

This adds a `build completed with one warning/x warnings` message, similar to the already present `aborted due to previous error` message.

Author: bors

src/librustc_errors/lib.rs

@@ -312,6 +312,9 @@ struct HandlerInner {
     /// The stashed diagnostics count towards the total error count.
     /// When `.abort_if_errors()` is called, these are also emitted.
     stashed_diagnostics: FxIndexMap<(Span, StashKey), Diagnostic>,
+
+    /// The warning count, used for a recap upon finishing
+    deduplicated_warn_count: usize,
 }
 
 /// A key denoting where from a diagnostic was stashed.
@@ -414,6 +417,7 @@ impl Handler {
                 flags,
                 err_count: 0,
                 deduplicated_err_count: 0,
+                deduplicated_warn_count: 0,
                 emitter,
                 delayed_span_bugs: Vec::new(),
                 taught_diagnostics: Default::default(),
@@ -439,6 +443,7 @@ impl Handler {
         let mut inner = self.inner.borrow_mut();
         inner.err_count = 0;
         inner.deduplicated_err_count = 0;
+        inner.deduplicated_warn_count = 0;
 
         // actually free the underlying memory (which `clear` would not do)
         inner.delayed_span_bugs = Default::default();
@@ -745,6 +750,8 @@ impl HandlerInner {
             self.emitter.emit_diagnostic(diagnostic);
             if diagnostic.is_error() {
                 self.deduplicated_err_count += 1;
+            } else if diagnostic.level == Warning {
+                self.deduplicated_warn_count += 1;
             }
         }
         if diagnostic.is_error() {
@@ -763,16 +770,30 @@ impl HandlerInner {
     fn print_error_count(&mut self, registry: &Registry) {
         self.emit_stashed_diagnostics();
 
-        let s = match self.deduplicated_err_count {
-            0 => return,
+        let warnings = match self.deduplicated_warn_count {
+            0 => String::new(),
+            1 => "1 warning emitted".to_string(),
+            count => format!("{} warnings emitted", count),
+        };
+        let errors = match self.deduplicated_err_count {
+            0 => String::new(),
             1 => "aborting due to previous error".to_string(),
             count => format!("aborting due to {} previous errors", count),
         };
         if self.treat_err_as_bug() {
             return;
         }
 
-        let _ = self.fatal(&s);
+        match (errors.len(), warnings.len()) {
+            (0, 0) => return,
+            (0, _) => self.emit_diagnostic(&Diagnostic::new(Level::Warning, &warnings)),
+            (_, 0) => {
+                let _ = self.fatal(&errors);
+            }
+            (_, _) => {
+                let _ = self.fatal(&format!("{}; {}", &errors, &warnings));
+            }
+        }
 
         let can_show_explain = self.emitter.should_show_explain();
         let are_there_diagnostics = !self.emitted_diagnostic_codes.is_empty();

src/test/rustdoc-ui/deprecated-attrs.stderr

@@ -7,3 +7,5 @@ warning: the `#![doc(passes = "...")]` attribute is considered deprecated
    |
    = warning: see issue #44136 <https://github.com/rust-lang/rust/issues/44136> for more information
 
+warning: 2 warnings emitted
+

src/test/rustdoc-ui/intra-links-warning-crlf.stderr

@@ -31,3 +31,5 @@ LL |  * It also has an [error].
    |
    = help: to escape `[` and `]` characters, just add '\' before them like `\[` or `\]`
 
+warning: 4 warnings emitted
+

src/test/rustdoc-ui/intra-links-warning.stderr

@@ -177,3 +177,5 @@ LL | f!("Foo\nbar [BarF] bar\nbaz");
    = help: to escape `[` and `]` characters, just add '\' before them like `\[` or `\]`
    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
+warning: 19 warnings emitted
+

src/test/rustdoc-ui/invalid-syntax.stderr

@@ -147,3 +147,5 @@ help: mark blocks that do not contain Rust code as text
 LL | /// ```text
    |     ^^^^^^^
 
+warning: 12 warnings emitted
+

src/test/ui-fulldeps/feature-gate-plugin.stderr

@@ -15,6 +15,6 @@ LL | #![plugin(empty_plugin)]
    |
    = note: `#[warn(deprecated)]` on by default
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0658`.

src/test/ui-fulldeps/gated-plugin.stderr

@@ -15,6 +15,6 @@ LL | #![plugin(empty_plugin)]
    |
    = note: `#[warn(deprecated)]` on by default
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0658`.

src/test/ui-fulldeps/issue-15778-fail.stderr

@@ -18,5 +18,5 @@ LL | | pub fn main() { }
    |
    = note: requested on the command line with `-D crate-not-okay`
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 

src/test/ui-fulldeps/issue-15778-pass.stderr

@@ -6,3 +6,5 @@ LL | #![plugin(lint_for_crate_rpass)]
    |
    = note: `#[warn(deprecated)]` on by default
 
+warning: 1 warning emitted
+

src/test/ui-fulldeps/issue-40001.stderr

@@ -6,3 +6,5 @@ LL | #![plugin(issue_40001_plugin)]
    |
    = note: `#[warn(deprecated)]` on by default
 
+warning: 1 warning emitted
+

src/test/ui-fulldeps/lint-group-plugin-deny-cmdline.stderr

@@ -22,5 +22,5 @@ LL | fn pleaselintme() { }
    |
    = note: `-D please-lint` implied by `-D lint-me`
 
-error: aborting due to 2 previous errors
+error: aborting due to 2 previous errors; 1 warning emitted
 

src/test/ui-fulldeps/lint-group-plugin.stderr

@@ -22,3 +22,5 @@ LL | fn pleaselintme() { }
    |
    = note: `#[warn(please_lint)]` on by default
 
+warning: 3 warnings emitted
+

src/test/ui-fulldeps/lint-plugin-cmdline-allow.stderr

@@ -6,3 +6,5 @@ LL | #![plugin(lint_plugin_test)]
    |
    = note: `#[warn(deprecated)]` on by default
 
+warning: 1 warning emitted
+

src/test/ui-fulldeps/lint-plugin-cmdline-load.stderr

@@ -14,3 +14,5 @@ LL | fn lintme() { }
    |
    = note: `#[warn(test_lint)]` on by default
 
+warning: 2 warnings emitted
+

src/test/ui-fulldeps/lint-plugin-deny-attr.stderr

@@ -18,5 +18,5 @@ note: the lint level is defined here
 LL | #![deny(test_lint)]
    |         ^^^^^^^^^
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 

src/test/ui-fulldeps/lint-plugin-deny-cmdline.stderr

@@ -14,5 +14,5 @@ LL | fn lintme() { }
    |
    = note: requested on the command line with `-D test-lint`
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 

src/test/ui-fulldeps/lint-plugin-forbid-attrs.stderr

@@ -45,6 +45,6 @@ LL | #![forbid(test_lint)]
 LL | #[allow(test_lint)]
    |         ^^^^^^^^^ overruled by previous forbid
 
-error: aborting due to 4 previous errors
+error: aborting due to 4 previous errors; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0453`.

src/test/ui-fulldeps/lint-plugin-forbid-cmdline.stderr

@@ -38,6 +38,6 @@ LL | #[allow(test_lint)]
    |
    = note: `forbid` lint level was set on command line
 
-error: aborting due to 4 previous errors
+error: aborting due to 4 previous errors; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0453`.

src/test/ui-fulldeps/lint-plugin.stderr

@@ -14,3 +14,5 @@ LL | fn lintme() { }
    |
    = note: `#[warn(test_lint)]` on by default
 
+warning: 2 warnings emitted
+

src/test/ui-fulldeps/lint-tool-cmdline-allow.stderr

@@ -30,3 +30,5 @@ warning: lint name `test_lint` is deprecated and does not have an effect anymore
    |
    = note: requested on the command line with `-A test_lint`
 
+warning: 6 warnings emitted
+

src/test/ui-fulldeps/lint-tool-test.stderr

@@ -96,5 +96,5 @@ warning: lint name `test_group` is deprecated and may not have an effect in the
 LL | #[allow(test_group)]
    |         ^^^^^^^^^^ help: change it to: `clippy::test_group`
 
-error: aborting due to 2 previous errors
+error: aborting due to 2 previous errors; 11 warnings emitted
 

src/test/ui-fulldeps/lto-syntax-extension.stderr

@@ -6,3 +6,5 @@ LL | #![plugin(lto_syntax_extension_plugin)]
    |
    = note: `#[warn(deprecated)]` on by default
 
+warning: 1 warning emitted
+

src/test/ui-fulldeps/macro-crate-rlib.stderr

@@ -12,5 +12,5 @@ LL | #![plugin(rlib_crate_test)]
    |
    = note: `#[warn(deprecated)]` on by default
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 

src/test/ui-fulldeps/outlive-expansion-phase.stderr

@@ -6,3 +6,5 @@ LL | #![plugin(outlive_expansion_phase)]
    |
    = note: `#[warn(deprecated)]` on by default
 
+warning: 1 warning emitted
+

src/test/ui-fulldeps/plugin-args.stderr

@@ -12,5 +12,5 @@ LL | #![plugin(empty_plugin(args))]
    |
    = note: `#[warn(deprecated)]` on by default
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 

src/test/ui/anon-params/anon-params-deprecated.stderr

@@ -30,3 +30,5 @@ LL |     fn bar_with_default_impl(String, String) {}
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
    = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
 
+warning: 3 warnings emitted
+

src/test/ui/array-slice-vec/match_arr_unknown_len.stderr

@@ -15,6 +15,6 @@ LL |         [1, 2] => true,
    = note: expected array `[u32; 2]`
               found array `[u32; _]`
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0308`.

src/test/ui/asm/asm-misplaced-option.stderr

@@ -10,3 +10,5 @@ warning: expected a clobber, found an option
 LL |         llvm_asm!("add $2, $1; mov $1, $0" : "=r"(x) : "r"(x), "r"(8_usize) : "cc", "volatile");
    |                                                                                     ^^^^^^^^^^
 
+warning: 2 warnings emitted
+

src/test/ui/associated-type-bounds/duplicate.stderr

@@ -726,6 +726,6 @@ error: could not find defining uses
 LL | type TADyn3 = dyn Iterator<Item: 'static, Item: 'static>;
    |                                           ^^^^^^^^^^^^^
 
-error: aborting due to 96 previous errors
+error: aborting due to 96 previous errors; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0719`.

src/test/ui/associated-type-bounds/dyn-lcsit.stderr

@@ -6,3 +6,5 @@ LL | #![feature(impl_trait_in_bindings)]
    |
    = note: `#[warn(incomplete_features)]` on by default
 
+warning: 1 warning emitted
+

src/test/ui/associated-type-bounds/lcsit.stderr

@@ -6,3 +6,5 @@ LL | #![feature(impl_trait_in_bindings)]
    |
    = note: `#[warn(incomplete_features)]` on by default
 
+warning: 1 warning emitted
+

src/test/ui/associated-type-bounds/type-alias.stderr

@@ -131,3 +131,5 @@ help: the bound will not be checked when the type alias is used, and should be r
 LL | type _TaInline6<T> = T;
    |                 --
 
+warning: 12 warnings emitted
+

src/test/ui/async-await/issues/issue-54752-async-block.stderr

@@ -6,3 +6,5 @@ LL | fn main() { let _a = (async  { }); }
    |
    = note: `#[warn(unused_parens)]` on by default
 
+warning: 1 warning emitted
+

src/test/ui/bad/bad-lint-cap3.stderr

@@ -11,3 +11,5 @@ LL | #![deny(warnings)]
    |         ^^^^^^^^
    = note: `#[warn(unused_imports)]` implied by `#[warn(warnings)]`
 
+warning: 1 warning emitted
+

src/test/ui/binding/const-param.stderr

@@ -12,6 +12,6 @@ error[E0158]: const parameters cannot be referenced in patterns
 LL |         N => {}
    |         ^
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0158`.

src/test/ui/binding/issue-53114-safety-checks.stderr

@@ -95,6 +95,6 @@ LL |     match (&u2.a,) { (_,) => { } }
    |
    = note: the field may not be properly initialized: using uninitialized data will cause undefined behavior
 
-error: aborting due to 7 previous errors
+error: aborting due to 7 previous errors; 4 warnings emitted
 
 For more information about this error, try `rustc --explain E0133`.

src/test/ui/block-expr-precedence.stderr

@@ -6,3 +6,5 @@ LL |   if (true) { 12; };;; -num;
    |
    = note: `#[warn(redundant_semicolons)]` on by default
 
+warning: 1 warning emitted
+

src/test/ui/block-result/block-must-not-have-result-while.stderr

@@ -12,6 +12,6 @@ error[E0308]: mismatched types
 LL |         true
    |         ^^^^ expected `()`, found `bool`
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0308`.

src/test/ui/borrowck/mut-borrow-in-loop.stderr

@@ -42,6 +42,6 @@ LL |             (self.func)(arg)
    |             |           mutable borrow starts here in previous iteration of loop
    |             argument requires that `*arg` is borrowed for `'a`
 
-error: aborting due to 3 previous errors
+error: aborting due to 3 previous errors; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0499`.

src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.migrate2015.stderr

@@ -35,6 +35,6 @@ LL |     v.push(shared.len());
    = warning: this borrowing pattern was not meant to be accepted, and may become a hard error in the future
    = note: for more information, see issue #59159 <https://github.com/rust-lang/rust/issues/59159>
 
-error: aborting due to 2 previous errors
+error: aborting due to 2 previous errors; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0502`.

src/test/ui/borrowck/two-phase-reservation-sharing-interference-2.migrate2018.stderr

@@ -35,6 +35,6 @@ LL |     v.push(shared.len());
    = warning: this borrowing pattern was not meant to be accepted, and may become a hard error in the future
    = note: for more information, see issue #59159 <https://github.com/rust-lang/rust/issues/59159>
 
-error: aborting due to 2 previous errors
+error: aborting due to 2 previous errors; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0502`.

src/test/ui/borrowck/two-phase-reservation-sharing-interference-future-compat-lint.stderr

@@ -36,5 +36,5 @@ LL |     #![deny(mutable_borrow_reservation_conflict)]
    = warning: this borrowing pattern was not meant to be accepted, and may become a hard error in the future
    = note: for more information, see issue #59159 <https://github.com/rust-lang/rust/issues/59159>
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 

src/test/ui/codemap_tests/unicode_3.stderr

@@ -6,3 +6,5 @@ LL |     let s = "ZͨA͑ͦ͒͋ͤ͑̚L̄͑͋Ĝͨͥ̿͒̽̈́Oͥ͛ͭ!̏"; while tru
    |
    = note: `#[warn(while_true)]` on by default
 
+warning: 1 warning emitted
+

src/test/ui/coherence/coherence-subtyping.old.stderr

@@ -12,3 +12,5 @@ LL | impl TheTrait for for<'a> fn(&'a u8, &'a u8) -> &'a u8 {
    = note: for more information, see issue #56105 <https://github.com/rust-lang/rust/issues/56105>
    = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
 
+warning: 1 warning emitted
+

src/test/ui/coherence/coherence-subtyping.re.stderr

@@ -12,3 +12,5 @@ LL | impl TheTrait for for<'a> fn(&'a u8, &'a u8) -> &'a u8 {
    = note: for more information, see issue #56105 <https://github.com/rust-lang/rust/issues/56105>
    = note: this behavior recently changed as a result of a bug fix; see rust-lang/rust#56105 for details
 
+warning: 1 warning emitted
+

src/test/ui/conditional-compilation/cfg-attr-multi-true.stderr

@@ -36,3 +36,5 @@ note: the lint level is defined here
 LL | #![warn(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
 
+warning: 5 warnings emitted
+

src/test/ui/const-generics/apit-with-const-param.stderr

@@ -6,3 +6,5 @@ LL | #![feature(const_generics)]
    |
    = note: `#[warn(incomplete_features)]` on by default
 
+warning: 1 warning emitted
+

src/test/ui/const-generics/argument_order.stderr

@@ -12,5 +12,5 @@ LL | #![feature(const_generics)]
    |
    = note: `#[warn(incomplete_features)]` on by default
 
-error: aborting due to previous error
+error: aborting due to previous error; 1 warning emitted
 

src/test/ui/const-generics/array-size-in-generic-struct-param.stderr

@@ -22,5 +22,5 @@ LL |     arr: [u8; CFG.arr_size],
    |
    = note: this may fail depending on what value the parameter takes
 
-error: aborting due to 2 previous errors
+error: aborting due to 2 previous errors; 1 warning emitted
 

src/test/ui/const-generics/array-wrapper-struct-ctor.stderr

@@ -6,3 +6,5 @@ LL | #![feature(const_generics)]
    |
    = note: `#[warn(incomplete_features)]` on by default
 
+warning: 1 warning emitted
+