From 69766e4f167f4097e1f8975bd866c1f782fa26d5 Mon Sep 17 00:00:00 2001
From: Nathan Stocks <cleancut@github.com>
Date: Sun, 25 Sep 2022 22:52:19 -0600
Subject: [PATCH] migrate loops.rs to translateable diagnostics

---
 .../locales/en-US/passes.ftl                  |  34 ++++
 compiler/rustc_passes/src/errors.rs           | 121 ++++++++++++-
 compiler/rustc_passes/src/loops.rs            | 161 +++++-------------
 3 files changed, 198 insertions(+), 118 deletions(-)

diff --git a/compiler/rustc_error_messages/locales/en-US/passes.ftl b/compiler/rustc_error_messages/locales/en-US/passes.ftl
index 550096469bb..3dc4204f986 100644
--- a/compiler/rustc_error_messages/locales/en-US/passes.ftl
+++ b/compiler/rustc_error_messages/locales/en-US/passes.ftl
@@ -433,3 +433,37 @@ passes_expr_not_allowed_in_context =
 passes_const_impl_const_trait =
     const `impl`s must be for traits marked with `#[const_trait]`
     .note = this trait must be annotated with `#[const_trait]`
+
+passes_break_non_loop =
+    `break` with value from a `{$kind}` loop
+    .label = can only break with a value inside `loop` or breakable block
+    .label2 = you can't `break` with a value in a `{$kind}` loop
+    .suggestion = use `break` on its own without a value inside this `{$kind}` loop
+    .break_expr_suggestion = alternatively, you might have meant to use the available loop label
+
+passes_continue_labeled_block =
+    `continue` pointing to a labeled block
+    .label = labeled blocks cannot be `continue`'d
+    .block_label = labeled block the `continue` points to
+
+passes_break_inside_closure =
+    `{$name}` inside of a closure
+    .label = cannot `{$name}` inside of a closure
+    .closure_label = enclosing closure
+
+passes_break_inside_async_block =
+    `{$name}` inside of an `async` block
+    .label = cannot `{$name}` inside of an `async` block
+    .async_block_label = enclosing `async` block
+
+passes_outside_loop =
+    `{$name}` outside of a loop
+    .label = cannot `{$name}` outside of a loop
+
+passes_unlabeled_in_labeled_block =
+    unlabeled `{$cf_type}` inside of a labeled block
+    .label = `{$cf_type}` statements that would diverge to or through a labeled block need to bear a label
+
+passes_unlabeled_cf_in_while_condition =
+    `break` or `continue` with no label in the condition of a `while` loop
+    .label = unlabeled `{$cf_type}` in the condition of a `while` loop
diff --git a/compiler/rustc_passes/src/errors.rs b/compiler/rustc_passes/src/errors.rs
index fe169c566f6..fcbcc298bd5 100644
--- a/compiler/rustc_passes/src/errors.rs
+++ b/compiler/rustc_passes/src/errors.rs
@@ -1,7 +1,8 @@
 use std::{io::Error, path::Path};
 
-use rustc_errors::{Applicability, ErrorGuaranteed, IntoDiagnostic, MultiSpan};
-use rustc_hir::Target;
+use rustc_ast::Label;
+use rustc_errors::{error_code, Applicability, ErrorGuaranteed, IntoDiagnostic, MultiSpan};
+use rustc_hir::{self as hir, ExprKind, Target};
 use rustc_macros::{Diagnostic, LintDiagnostic, Subdiagnostic};
 use rustc_span::{Span, Symbol};
 
@@ -870,3 +871,119 @@ pub struct ConstImplConstTrait {
     #[note]
     pub def_span: Span,
 }
+
+pub struct BreakNonLoop<'a> {
+    pub span: Span,
+    pub head: Option<Span>,
+    pub kind: &'a str,
+    pub suggestion: String,
+    pub loop_label: Option<Label>,
+    pub break_label: Option<Label>,
+    pub break_expr_kind: &'a ExprKind<'a>,
+    pub break_expr_span: Span,
+}
+
+impl<'a> IntoDiagnostic<'_> for BreakNonLoop<'a> {
+    fn into_diagnostic(
+        self,
+        handler: &rustc_errors::Handler,
+    ) -> rustc_errors::DiagnosticBuilder<'_, ErrorGuaranteed> {
+        let mut diag = handler.struct_span_err_with_code(
+            self.span,
+            rustc_errors::fluent::passes::break_non_loop,
+            error_code!(E0571),
+        );
+        diag.set_arg("kind", self.kind);
+        diag.span_label(self.span, rustc_errors::fluent::passes::label);
+        if let Some(head) = self.head {
+            diag.span_label(head, rustc_errors::fluent::passes::label2);
+        }
+        diag.span_suggestion(
+            self.span,
+            rustc_errors::fluent::passes::suggestion,
+            self.suggestion,
+            Applicability::MaybeIncorrect,
+        );
+        if let (Some(label), None) = (self.loop_label, self.break_label) {
+            match self.break_expr_kind {
+                ExprKind::Path(hir::QPath::Resolved(
+                    None,
+                    hir::Path { segments: [segment], res: hir::def::Res::Err, .. },
+                )) if label.ident.to_string() == format!("'{}", segment.ident) => {
+                    // This error is redundant, we will have already emitted a
+                    // suggestion to use the label when `segment` wasn't found
+                    // (hence the `Res::Err` check).
+                    diag.delay_as_bug();
+                }
+                _ => {
+                    diag.span_suggestion(
+                        self.break_expr_span,
+                        rustc_errors::fluent::passes::break_expr_suggestion,
+                        label.ident,
+                        Applicability::MaybeIncorrect,
+                    );
+                }
+            }
+        }
+        diag
+    }
+}
+
+#[derive(Diagnostic)]
+#[diag(passes::continue_labeled_block, code = "E0696")]
+pub struct ContinueLabeledBlock {
+    #[primary_span]
+    #[label]
+    pub span: Span,
+    #[label(passes::block_label)]
+    pub block_span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(passes::break_inside_closure, code = "E0267")]
+pub struct BreakInsideClosure<'a> {
+    #[primary_span]
+    #[label]
+    pub span: Span,
+    #[label(passes::closure_label)]
+    pub closure_span: Span,
+    pub name: &'a str,
+}
+
+#[derive(Diagnostic)]
+#[diag(passes::break_inside_async_block, code = "E0267")]
+pub struct BreakInsideAsyncBlock<'a> {
+    #[primary_span]
+    #[label]
+    pub span: Span,
+    #[label(passes::async_block_label)]
+    pub closure_span: Span,
+    pub name: &'a str,
+}
+
+#[derive(Diagnostic)]
+#[diag(passes::outside_loop, code = "E0268")]
+pub struct OutsideLoop<'a> {
+    #[primary_span]
+    #[label]
+    pub span: Span,
+    pub name: &'a str,
+}
+
+#[derive(Diagnostic)]
+#[diag(passes::unlabeled_in_labeled_block, code = "E0695")]
+pub struct UnlabeledInLabeledBlock<'a> {
+    #[primary_span]
+    #[label]
+    pub span: Span,
+    pub cf_type: &'a str,
+}
+
+#[derive(Diagnostic)]
+#[diag(passes::unlabeled_cf_in_while_condition, code = "E0590")]
+pub struct UnlabeledCfInWhileCondition<'a> {
+    #[primary_span]
+    #[label]
+    pub span: Span,
+    pub cf_type: &'a str,
+}
diff --git a/compiler/rustc_passes/src/loops.rs b/compiler/rustc_passes/src/loops.rs
index cdda0e388dd..077194ec687 100644
--- a/compiler/rustc_passes/src/loops.rs
+++ b/compiler/rustc_passes/src/loops.rs
@@ -1,6 +1,5 @@
 use Context::*;
 
-use rustc_errors::{struct_span_err, Applicability};
 use rustc_hir as hir;
 use rustc_hir::def_id::LocalDefId;
 use rustc_hir::intravisit::{self, Visitor};
@@ -13,6 +12,11 @@ use rustc_session::Session;
 use rustc_span::hygiene::DesugaringKind;
 use rustc_span::Span;
 
+use crate::errors::{
+    BreakInsideAsyncBlock, BreakInsideClosure, BreakNonLoop, ContinueLabeledBlock, OutsideLoop,
+    UnlabeledCfInWhileCondition, UnlabeledInLabeledBlock,
+};
+
 #[derive(Clone, Copy, Debug, PartialEq)]
 enum Context {
     Normal,
@@ -90,7 +94,10 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
                     Ok(loop_id) => Some(loop_id),
                     Err(hir::LoopIdError::OutsideLoopScope) => None,
                     Err(hir::LoopIdError::UnlabeledCfInWhileCondition) => {
-                        self.emit_unlabled_cf_in_while_condition(e.span, "break");
+                        self.sess.emit_err(UnlabeledCfInWhileCondition {
+                            span: e.span,
+                            cf_type: "break",
+                        });
                         None
                     }
                     Err(hir::LoopIdError::UnresolvedLabel) => None,
@@ -116,69 +123,22 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
                     match loop_kind {
                         None | Some(hir::LoopSource::Loop) => (),
                         Some(kind) => {
-                            let mut err = struct_span_err!(
-                                self.sess,
-                                e.span,
-                                E0571,
-                                "`break` with value from a `{}` loop",
-                                kind.name()
+                            let suggestion = format!(
+                                "break{}",
+                                break_label
+                                    .label
+                                    .map_or_else(String::new, |l| format!(" {}", l.ident))
                             );
-                            err.span_label(
-                                e.span,
-                                "can only break with a value inside `loop` or breakable block",
-                            );
-                            if let Some(head) = head {
-                                err.span_label(
-                                    head,
-                                    &format!(
-                                        "you can't `break` with a value in a `{}` loop",
-                                        kind.name()
-                                    ),
-                                );
-                            }
-                            err.span_suggestion(
-                                e.span,
-                                &format!(
-                                    "use `break` on its own without a value inside this `{}` loop",
-                                    kind.name(),
-                                ),
-                                format!(
-                                    "break{}",
-                                    break_label
-                                        .label
-                                        .map_or_else(String::new, |l| format!(" {}", l.ident))
-                                ),
-                                Applicability::MaybeIncorrect,
-                            );
-                            if let (Some(label), None) = (loop_label, break_label.label) {
-                                match break_expr.kind {
-                                    hir::ExprKind::Path(hir::QPath::Resolved(
-                                        None,
-                                        hir::Path {
-                                            segments: [segment],
-                                            res: hir::def::Res::Err,
-                                            ..
-                                        },
-                                    )) if label.ident.to_string()
-                                        == format!("'{}", segment.ident) =>
-                                    {
-                                        // This error is redundant, we will have already emitted a
-                                        // suggestion to use the label when `segment` wasn't found
-                                        // (hence the `Res::Err` check).
-                                        err.delay_as_bug();
-                                    }
-                                    _ => {
-                                        err.span_suggestion(
-                                            break_expr.span,
-                                            "alternatively, you might have meant to use the \
-                                             available loop label",
-                                            label.ident,
-                                            Applicability::MaybeIncorrect,
-                                        );
-                                    }
-                                }
-                            }
-                            err.emit();
+                            self.sess.emit_err(BreakNonLoop {
+                                span: e.span,
+                                head,
+                                kind: kind.name(),
+                                suggestion,
+                                loop_label,
+                                break_label: break_label.label,
+                                break_expr_kind: &break_expr.kind,
+                                break_expr_span: break_expr.span,
+                            });
                         }
                     }
                 }
@@ -191,19 +151,17 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
                 match destination.target_id {
                     Ok(loop_id) => {
                         if let Node::Block(block) = self.hir_map.find(loop_id).unwrap() {
-                            struct_span_err!(
-                                self.sess,
-                                e.span,
-                                E0696,
-                                "`continue` pointing to a labeled block"
-                            )
-                            .span_label(e.span, "labeled blocks cannot be `continue`'d")
-                            .span_label(block.span, "labeled block the `continue` points to")
-                            .emit();
+                            self.sess.emit_err(ContinueLabeledBlock {
+                                span: e.span,
+                                block_span: block.span,
+                            });
                         }
                     }
                     Err(hir::LoopIdError::UnlabeledCfInWhileCondition) => {
-                        self.emit_unlabled_cf_in_while_condition(e.span, "continue");
+                        self.sess.emit_err(UnlabeledCfInWhileCondition {
+                            span: e.span,
+                            cf_type: "continue",
+                        });
                     }
                     Err(_) => {}
                 }
@@ -226,21 +184,16 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
     }
 
     fn require_break_cx(&self, name: &str, span: Span) {
-        let err_inside_of = |article, ty, closure_span| {
-            struct_span_err!(self.sess, span, E0267, "`{}` inside of {} {}", name, article, ty)
-                .span_label(span, format!("cannot `{}` inside of {} {}", name, article, ty))
-                .span_label(closure_span, &format!("enclosing {}", ty))
-                .emit();
-        };
-
         match self.cx {
             LabeledBlock | Loop(_) => {}
-            Closure(closure_span) => err_inside_of("a", "closure", closure_span),
-            AsyncClosure(closure_span) => err_inside_of("an", "`async` block", closure_span),
+            Closure(closure_span) => {
+                self.sess.emit_err(BreakInsideClosure { span, closure_span, name });
+            }
+            AsyncClosure(closure_span) => {
+                self.sess.emit_err(BreakInsideAsyncBlock { span, closure_span, name });
+            }
             Normal | AnonConst => {
-                struct_span_err!(self.sess, span, E0268, "`{}` outside of a loop", name)
-                    .span_label(span, format!("cannot `{}` outside of a loop", name))
-                    .emit();
+                self.sess.emit_err(OutsideLoop { span, name });
             }
         }
     }
@@ -251,37 +204,13 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
         label: &Destination,
         cf_type: &str,
     ) -> bool {
-        if !span.is_desugaring(DesugaringKind::QuestionMark) && self.cx == LabeledBlock {
-            if label.label.is_none() {
-                struct_span_err!(
-                    self.sess,
-                    span,
-                    E0695,
-                    "unlabeled `{}` inside of a labeled block",
-                    cf_type
-                )
-                .span_label(
-                    span,
-                    format!(
-                        "`{}` statements that would diverge to or through \
-                                a labeled block need to bear a label",
-                        cf_type
-                    ),
-                )
-                .emit();
-                return true;
-            }
+        if !span.is_desugaring(DesugaringKind::QuestionMark)
+            && self.cx == LabeledBlock
+            && label.label.is_none()
+        {
+            self.sess.emit_err(UnlabeledInLabeledBlock { span, cf_type });
+            return true;
         }
         false
     }
-    fn emit_unlabled_cf_in_while_condition(&mut self, span: Span, cf_type: &str) {
-        struct_span_err!(
-            self.sess,
-            span,
-            E0590,
-            "`break` or `continue` with no label in the condition of a `while` loop"
-        )
-        .span_label(span, format!("unlabeled `{}` in the condition of a `while` loop", cf_type))
-        .emit();
-    }
 }