add medium rendering mode

just added it onto the short diagnostic rendering
otherwise big chunks of code would be duplicated

codespan-reporting/src/term.rs

@@ -94,7 +94,8 @@ pub fn emit<'files, F: Files<'files>>(
     let mut renderer = Renderer::new(writer, config);
     match config.display_style {
         DisplayStyle::Rich => RichDiagnostic::new(diagnostic).render(files, &mut renderer),
-        DisplayStyle::Short => ShortDiagnostic::new(diagnostic).render(files, &mut renderer),
+        DisplayStyle::Medium => ShortDiagnostic::new(diagnostic, true).render(files, &mut renderer),
+        DisplayStyle::Short => ShortDiagnostic::new(diagnostic, false).render(files, &mut renderer),
     }
 }
 

codespan-reporting/src/term/config.rs

@@ -59,6 +59,16 @@ pub enum DisplayStyle {
     ///
     /// ```
     Rich,
+    /// Output a condensed diagnostic, with a line number, severity, message and notes (if any).
+    ///
+    /// ```text
+    /// test:2:9: error[E0001]: unexpected type in `+` application
+    /// = expected type `Int`
+    ///      found type `String`
+    ///
+    /// error[E0002]: Bad config found
+    /// ```
+    Medium,
     /// Output a short diagnostic, with a line number, severity, and message.
     ///
     /// ```text

codespan-reporting/src/term/views.rs

@@ -419,6 +419,7 @@ where
 /// Output a short diagnostic, with a line number, severity, and message.
 pub struct ShortDiagnostic<'diagnostic, FileId> {
     diagnostic: &'diagnostic Diagnostic<FileId>,
+    show_notes: bool
 }
 
 impl<'diagnostic, FileId> ShortDiagnostic<'diagnostic, FileId>
@@ -427,8 +428,9 @@ where
 {
     pub fn new(
         diagnostic: &'diagnostic Diagnostic<FileId>,
+        show_notes: bool,
     ) -> ShortDiagnostic<'diagnostic, FileId> {
-        ShortDiagnostic { diagnostic }
+        ShortDiagnostic { diagnostic, show_notes }
     }
 
     pub fn render<'files>(
@@ -474,6 +476,19 @@ where
             )?;
         }
 
+        if self.show_notes {
+            // Additional notes
+            //
+            // ```text
+            // = expected type `Int`
+            //      found type `String`
+            // ```
+            for note in &self.diagnostic.notes {
+                renderer.render_snippet_note(0, note)?;
+            }
+            renderer.render_empty()?;
+        }
+
         Ok(())
     }
 }