From ca7df9a2a9c4b1f751e91040fe659f682c976919 Mon Sep 17 00:00:00 2001
From: Rejyr <jerrylwang123@gmail.com>
Date: Wed, 9 Nov 2022 19:34:49 -0500
Subject: [PATCH] migrate: `for_loops_over_fallibles.rs`
---
.../locales/en-US/lint.ftl | 7 ++
.../src/for_loops_over_fallibles.rs | 73 +++++++------------
compiler/rustc_lint/src/lints.rs | 49 +++++++++++++
3 files changed, 84 insertions(+), 45 deletions(-)
diff --git a/compiler/rustc_error_messages/locales/en-US/lint.ftl b/compiler/rustc_error_messages/locales/en-US/lint.ftl
index 1080ba2d2b5..5330ce504b2 100644
--- a/compiler/rustc_error_messages/locales/en-US/lint.ftl
+++ b/compiler/rustc_error_messages/locales/en-US/lint.ftl
@@ -16,6 +16,13 @@ lint_enum_intrinsics_mem_variant =
lint_expectation = this lint expectation is unfulfilled
.note = the `unfulfilled_lint_expectations` lint can't be expected and will always produce this message
+lint_for_loops_over_fallibles =
+ for loop over {$article} `{$ty}`. This is more readably written as an `if let` statement
+ .suggestion = consider using `if let` to clear intent
+ .remove_next = to iterate over `{$recv_snip}` remove the call to `next`
+ .use_while_let = to check pattern in a loop use `while let`
+ .use_question_mark = consider unwrapping the `Result` with `?` to iterate over its contents
+
lint_non_binding_let_on_sync_lock =
non-binding let on a synchronization lock
diff --git a/compiler/rustc_lint/src/for_loops_over_fallibles.rs b/compiler/rustc_lint/src/for_loops_over_fallibles.rs
index 182734fa9fc..7526b8c0632 100644
--- a/compiler/rustc_lint/src/for_loops_over_fallibles.rs
+++ b/compiler/rustc_lint/src/for_loops_over_fallibles.rs
@@ -1,7 +1,14 @@
-use crate::{LateContext, LateLintPass, LintContext};
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
+use crate::{
+ lints::{
+ ForLoopsOverFalliblesDiag, ForLoopsOverFalliblesLoopSub, ForLoopsOverFalliblesQuestionMark,
+ ForLoopsOverFalliblesSuggestion,
+ },
+ LateContext, LateLintPass, LintContext,
+};
use hir::{Expr, Pat};
-use rustc_errors::{Applicability, DelayDm};
use rustc_hir as hir;
use rustc_infer::{infer::TyCtxtInferExt, traits::ObligationCause};
use rustc_middle::ty::{self, List};
@@ -53,53 +60,29 @@ impl<'tcx> LateLintPass<'tcx> for ForLoopsOverFallibles {
_ => return,
};
- let msg = DelayDm(|| {
- format!(
- "for loop over {article} `{ty}`. This is more readably written as an `if let` statement",
- )
- });
-
- cx.struct_span_lint(FOR_LOOPS_OVER_FALLIBLES, arg.span, msg, |lint| {
- if let Some(recv) = extract_iterator_next_call(cx, arg)
+ let sub = if let Some(recv) = extract_iterator_next_call(cx, arg)
&& let Ok(recv_snip) = cx.sess().source_map().span_to_snippet(recv.span)
{
- lint.span_suggestion(
- recv.span.between(arg.span.shrink_to_hi()),
- format!("to iterate over `{recv_snip}` remove the call to `next`"),
- ".by_ref()",
- Applicability::MaybeIncorrect
- );
+ ForLoopsOverFalliblesLoopSub::RemoveNext { suggestion: recv.span.between(arg.span.shrink_to_hi()), recv_snip }
} else {
- lint.multipart_suggestion_verbose(
- "to check pattern in a loop use `while let`",
- vec![
- // NB can't use `until` here because `expr.span` and `pat.span` have different syntax contexts
- (expr.span.with_hi(pat.span.lo()), format!("while let {var}(")),
- (pat.span.between(arg.span), ") = ".to_string()),
- ],
- Applicability::MaybeIncorrect
- );
- }
+ ForLoopsOverFalliblesLoopSub::UseWhileLet { start_span: expr.span.with_hi(pat.span.lo()), end_span: pat.span.between(arg.span), var }
+ } ;
+ let question_mark = if suggest_question_mark(cx, adt, substs, expr.span) {
+ Some(ForLoopsOverFalliblesQuestionMark { suggestion: arg.span.shrink_to_hi() })
+ } else {
+ None
+ };
+ let suggestion = ForLoopsOverFalliblesSuggestion {
+ var,
+ start_span: expr.span.with_hi(pat.span.lo()),
+ end_span: pat.span.between(arg.span),
+ };
- if suggest_question_mark(cx, adt, substs, expr.span) {
- lint.span_suggestion(
- arg.span.shrink_to_hi(),
- "consider unwrapping the `Result` with `?` to iterate over its contents",
- "?",
- Applicability::MaybeIncorrect,
- );
- }
-
- lint.multipart_suggestion_verbose(
- "consider using `if let` to clear intent",
- vec![
- // NB can't use `until` here because `expr.span` and `pat.span` have different syntax contexts
- (expr.span.with_hi(pat.span.lo()), format!("if let {var}(")),
- (pat.span.between(arg.span), ") = ".to_string()),
- ],
- Applicability::MaybeIncorrect,
- )
- })
+ cx.emit_spanned_lint(
+ FOR_LOOPS_OVER_FALLIBLES,
+ arg.span,
+ ForLoopsOverFalliblesDiag { article, ty, sub, question_mark, suggestion },
+ );
}
}
diff --git a/compiler/rustc_lint/src/lints.rs b/compiler/rustc_lint/src/lints.rs
index 782cf668b29..a3549346604 100644
--- a/compiler/rustc_lint/src/lints.rs
+++ b/compiler/rustc_lint/src/lints.rs
@@ -333,6 +333,55 @@ impl<'a> DecorateLint<'a, ()> for Expectation<'_> {
}
}
+// for_loops_over_fallibles.rs
+#[derive(LintDiagnostic)]
+#[diag(lint_for_loops_over_fallibles)]
+pub struct ForLoopsOverFalliblesDiag<'a> {
+ pub article: &'static str,
+ pub ty: &'static str,
+ #[subdiagnostic]
+ pub sub: ForLoopsOverFalliblesLoopSub<'a>,
+ #[subdiagnostic]
+ pub question_mark: Option<ForLoopsOverFalliblesQuestionMark>,
+ #[subdiagnostic]
+ pub suggestion: ForLoopsOverFalliblesSuggestion<'a>,
+}
+
+#[derive(Subdiagnostic)]
+pub enum ForLoopsOverFalliblesLoopSub<'a> {
+ #[suggestion(remove_next, code = ".by_ref()", applicability = "maybe-incorrect")]
+ RemoveNext {
+ #[primary_span]
+ suggestion: Span,
+ recv_snip: String,
+ },
+ #[multipart_suggestion(use_while_let, applicability = "maybe-incorrect")]
+ UseWhileLet {
+ #[suggestion_part(code = "while let {var}(")]
+ start_span: Span,
+ #[suggestion_part(code = ") = ")]
+ end_span: Span,
+ var: &'a str,
+ },
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion(use_question_mark, code = "?", applicability = "maybe-incorrect")]
+pub struct ForLoopsOverFalliblesQuestionMark {
+ #[primary_span]
+ pub suggestion: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(suggestion, applicability = "maybe-incorrect")]
+pub struct ForLoopsOverFalliblesSuggestion<'a> {
+ pub var: &'a str,
+ #[suggestion_part(code = "if let {var}(")]
+ pub start_span: Span,
+ #[suggestion_part(code = ") = ")]
+ pub end_span: Span,
+}
+
// internal.rs
#[derive(LintDiagnostic)]
#[diag(lint_default_hash_types)]