Update compiler/rustc_borrowck/src/diagnostics/region_errors.rs

xizheyin · lcnr · web-flow · commit a8b0eb7c65bb · 2025-04-08T17:36:44.000+08:00
Co-authored-by: lcnr &lt;rust@lcnr.de&gt;
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
@@ -198,7 +198,8 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
 
     /// Returns `true` if a closure is inferred to be an `FnMut` closure.
     fn is_closure_fn_mut(&self, fr: RegionVid) -> bool {
-        if let Some(ty::ReLateParam(late_param)) = self.to_error_region(fr).map(|r| r.kind())
+        if let Some(r) = self.to_error_region(fr)
+            && let ty::ReLateParam(late_param) = r.kind()
             && let ty::LateParamRegionKind::ClosureEnv = late_param.kind
             && let DefiningTy::Closure(_, args) = self.regioncx.universal_regions().defining_ty
         {

Original file line number	Diff line number	Diff line change
`@@ -198,7 +198,8 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {`
`198`	`198`
`199`	`199`	/// Returns `true` if a closure is inferred to be an `FnMut` closure.
`200`	`200`	`fn is_closure_fn_mut(&self, fr: RegionVid) -> bool {`
`201`		`- if let Some(ty::ReLateParam(late_param)) = self.to_error_region(fr).map(\|r\| r.kind())`
	`201`	`+ if let Some(r) = self.to_error_region(fr)`
	`202`	`+ && let ty::ReLateParam(late_param) = r.kind()`
`202`	`203`	`&& let ty::LateParamRegionKind::ClosureEnv = late_param.kind`
`203`	`204`	`&& let DefiningTy::Closure(_, args) = self.regioncx.universal_regions().defining_ty`
`204`	`205`	`{`