Rollup merge of #58296 - estebank:hidden-suggestion, r=oli-obk

Hidden suggestion support

Add way to hide suggestion snippet window from cli output to avoid cluttered spans that don't enhance understanding.

r? @pietroalbini CC @zackmdavis

src/librustc_errors/lib.rs

@@ -69,6 +69,29 @@ pub enum Applicability {
     Unspecified,
 }
 
+#[derive(Debug, PartialEq, Eq, Clone, Copy, Hash, RustcEncodable, RustcDecodable)]
+pub enum SuggestionStyle {
+    /// Hide the suggested code when displaying this suggestion inline.
+    HideCodeInline,
+    /// Always hide the suggested code but display the message.
+    HideCodeAlways,
+    /// Do not display this suggestion in the cli output, it is only meant for tools.
+    CompletelyHidden,
+    /// Always show the suggested code.
+    /// This will *not* show the code if the suggestion is inline *and* the suggested code is
+    /// empty.
+    ShowCode,
+}
+
+impl SuggestionStyle {
+    fn hide_inline(&self) -> bool {
+        match *self {
+            SuggestionStyle::ShowCode => false,
+            _ => true,
+        }
+    }
+}
+
 #[derive(Clone, Debug, PartialEq, Hash, RustcEncodable, RustcDecodable)]
 pub struct CodeSuggestion {
     /// Each substitute can have multiple variants due to multiple
@@ -94,7 +117,8 @@ pub struct CodeSuggestion {
     /// ```
     pub substitutions: Vec<Substitution>,
     pub msg: String,
-    pub show_code_when_inline: bool,
+    /// Visual representation of this suggestion.
+    pub style: SuggestionStyle,
     /// Whether or not the suggestion is approximate
     ///
     /// Sometimes we may show suggestions with placeholders,