Implement assertions and fixes to not emit empty spans without suggestions

[rust.git] / compiler / rustc_parse / src / parser / diagnostics.rs

diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs
index f57bd9cec19200610617ed28edb52115ef57ec84..7e11ca57cebdad6b271efb01a5f4f6c0f5d0743c 100644 (file)
--- a/compiler/rustc_parse/src/parser/diagnostics.rs
+++ b/compiler/rustc_parse/src/parser/diagnostics.rs
@@ -1374,9 +1374,17 @@ fn inc_dec_standalone_suggest(
         kind: IncDecRecovery,
         (pre_span, post_span): (Span, Span),
     ) -> MultiSugg {
+        let mut patches = Vec::new();
+
+        if !pre_span.is_empty() {
+            patches.push((pre_span, String::new()));
+        }
+
+        patches.push((post_span, format!(" {}= 1", kind.op.chr())));
+
         MultiSugg {
             msg: format!("use `{}= 1` instead", kind.op.chr()),
-            patches: vec![(pre_span, String::new()), (post_span, format!(" {}= 1", kind.op.chr()))],
+            patches,
             applicability: Applicability::MachineApplicable,
         }
     }
@@ -2232,7 +2240,7 @@ pub fn recover_const_param_declaration(
     ///
     /// When encountering code like `foo::< bar + 3 >` or `foo::< bar - baz >` we suggest
     /// `foo::<{ bar + 3 }>` and `foo::<{ bar - baz }>`, respectively. We only provide a suggestion
-    /// if we think that that the resulting expression would be well formed.
+    /// if we think that the resulting expression would be well formed.
     pub fn recover_const_arg(
         &mut self,
         start: Span,