Add backticks to various diagnostics

Author: varkor

src/librustc/infer/error_reporting/mod.rs

@@ -661,7 +661,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
             },
             ObligationCauseCode::IfExpression(box IfExpressionCause { then, outer, semicolon }) => {
                 err.span_label(then, "expected because of this");
-                outer.map(|sp| err.span_label(sp, "if and else have incompatible types"));
+                outer.map(|sp| err.span_label(sp, "`if` and `else` have incompatible types"));
                 if let Some(sp) = semicolon {
                     err.span_suggestion_short(
                         sp,
@@ -1883,13 +1883,13 @@ impl<'tcx> ObligationCause<'tcx> {
                     hir::MatchSource::TryDesugar => {
                         "try expression alternatives have incompatible types"
                     }
-                    _ => "match arms have incompatible types",
+                    _ => "`match` arms have incompatible types",
                 })
             }
-            IfExpression { .. } => Error0308("if and else have incompatible types"),
-            IfExpressionWithNoElse => Error0317("if may be missing an else clause"),
-            MainFunctionType => Error0580("main function has wrong type"),
-            StartFunctionType => Error0308("start function has wrong type"),
+            IfExpression { .. } => Error0308("`if` and `else` have incompatible types"),
+            IfExpressionWithNoElse => Error0317("`if` may be missing an `else` clause"),
+            MainFunctionType => Error0580("`main` function has wrong type"),
+            StartFunctionType => Error0308("`#[start]` function has wrong type"),
             IntrinsicType => Error0308("intrinsic has wrong type"),
             MethodReceiver => Error0308("mismatched `self` parameter type"),
 
@@ -1917,12 +1917,12 @@ impl<'tcx> ObligationCause<'tcx> {
             ExprAssignable => "expression is assignable",
             MatchExpressionArm(box MatchExpressionArmCause { source, .. }) => match source {
                 hir::MatchSource::IfLetDesugar { .. } => "`if let` arms have compatible types",
-                _ => "match arms have compatible types",
+                _ => "`match` arms have compatible types",
             },
-            IfExpression { .. } => "if and else have incompatible types",
-            IfExpressionWithNoElse => "if missing an else returns ()",
+            IfExpression { .. } => "`if` and `else` have incompatible types",
+            IfExpressionWithNoElse => "`if` missing an `else` returns `()`",
             MainFunctionType => "`main` function has the correct type",
-            StartFunctionType => "`start` function has the correct type",
+            StartFunctionType => "`#[start]` function has the correct type",
             IntrinsicType => "intrinsic has the correct type",
             MethodReceiver => "method receiver has the correct type",
             _ => "types are compatible",

src/librustc_passes/entry.rs

@@ -134,7 +134,7 @@ fn find_item(item: &Item<'_>, ctxt: &mut EntryContext<'_, '_>, at_root: bool) {
                 ctxt.start_fn = Some((item.hir_id, item.span));
             } else {
                 struct_span_err!(ctxt.session, item.span, E0138, "multiple `start` functions")
-                    .span_label(ctxt.start_fn.unwrap().1, "previous `start` function here")
+                    .span_label(ctxt.start_fn.unwrap().1, "previous `#[start]` function here")
                     .span_label(item.span, "multiple `start` functions")
                     .emit();
             }

src/librustc_target/spec/wasm32_base.rs

@@ -81,7 +81,7 @@ pub fn options() -> TargetOptions {
         dynamic_linking: true,
         only_cdylib: true,
 
-        // This means we'll just embed a `start` function in the wasm module
+        // This means we'll just embed a `#[start]` function in the wasm module
         executables: true,
 
         // relatively self-explanatory!

src/librustc_typeck/check/_match.rs

@@ -298,7 +298,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             // LL ||         10u32
             //    ||         ^^^^^ expected `i32`, found `u32`
             // LL ||     };
-            //    ||_____- if and else have incompatible types
+            //    ||_____- `if` and `else` have incompatible types
             // ```
             Some(span)
         } else {
@@ -340,7 +340,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 // by not pointing at the entire expression:
                 // ```
                 // 2 |       let x = if true {
-                //   |               ------- if and else have incompatible types
+                //   |               ------- `if` and `else` have incompatible types
                 // 3 |           3
                 //   |           - expected because of this
                 // 4 |       } else {

src/libsyntax/feature_gate/check.rs

@@ -387,8 +387,8 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
                         &self,
                         start,
                         i.span,
-                        "a `#[start]` function is an experimental \
-                                       feature whose signature may change \
+                        "`#[start]` functions are experimental \
+                                       and their signature may change \
                                        over time"
                     );
                 }

src/test/ui/async-await/issue-66387-if-without-else.rs

@@ -1,6 +1,6 @@
 // edition:2018
 async fn f() -> i32 {
-    if true { //~ ERROR if may be missing an else clause
+    if true { //~ ERROR `if` may be missing an `else` clause
         return 0;
     }
     // An `if` block without `else` causes the type table not to have a type for this expr.

src/test/ui/async-await/issue-66387-if-without-else.stderr

@@ -1,4 +1,4 @@
-error[E0317]: if may be missing an else clause
+error[E0317]: `if` may be missing an `else` clause
   --> $DIR/issue-66387-if-without-else.rs:3:5
    |
 LL | /     if true {

src/test/ui/bad/bad-expr-path.rs

@@ -1,6 +1,6 @@
 mod m1 {}
 
-fn main(arguments: Vec<String>) { //~ ERROR main function has wrong type
+fn main(arguments: Vec<String>) { //~ ERROR `main` function has wrong type
     log(debug, m1::arguments);
     //~^ ERROR cannot find function `log` in this scope
     //~| ERROR cannot find value `debug` in this scope

src/test/ui/bad/bad-expr-path.stderr

@@ -16,7 +16,7 @@ error[E0425]: cannot find value `arguments` in module `m1`
 LL |     log(debug, m1::arguments);
    |                    ^^^^^^^^^ not found in `m1`
 
-error[E0580]: main function has wrong type
+error[E0580]: `main` function has wrong type
   --> $DIR/bad-expr-path.rs:3:1
    |
 LL | fn main(arguments: Vec<String>) {

src/test/ui/bad/bad-expr-path2.rs

@@ -2,7 +2,7 @@ mod m1 {
     pub mod arguments {}
 }
 
-fn main(arguments: Vec<String>) { //~ ERROR main function has wrong type
+fn main(arguments: Vec<String>) { //~ ERROR `main` function has wrong type
     log(debug, m1::arguments);
     //~^ ERROR cannot find function `log` in this scope
     //~| ERROR cannot find value `debug` in this scope