tweak notes on ignore/compile_fail examples

Author: QuietMisdreavus

src/librustdoc/html/highlight.rs

@@ -42,7 +42,7 @@ pub fn render_with_highlighting(src: &str, class: Option<&str>, id: Option<&str>
 
     let mut out = Vec::new();
     if let Some((tooltip, class)) = tooltip {
-        write!(out, "<div class='information'><div class='tooltip {}'>⚠<span \
+        write!(out, "<div class='information'><div class='tooltip {}'>ⓘ<span \
                      class='tooltiptext'>{}</span></div></div>",
                class, tooltip).unwrap();
     }

src/librustdoc/html/markdown.rs

@@ -228,9 +228,9 @@ impl<'a, I: Iterator<Item = Event<'a>>> Iterator for CodeBlocks<'a, I> {
                 ))
             });
             let tooltip = if ignore {
-                Some(("Be careful when using this code, it's not being tested!", "ignore"))
+                Some(("This example is not tested", "ignore"))
             } else if compile_fail {
-                Some(("This code doesn't compile so be extra careful!", "compile_fail"))
+                Some(("This example deliberately fails to compile", "compile_fail"))
             } else {
                 None
             };
@@ -639,9 +639,9 @@ pub fn render(w: &mut fmt::Formatter,
                     ))
                 });
                 let tooltip = if ignore {
-                    Some(("Be careful when using this code, it's not being tested!", "ignore"))
+                    Some(("This example is not tested", "ignore"))
                 } else if compile_fail {
-                    Some(("This code doesn't compile so be extra careful!", "compile_fail"))
+                    Some(("This example deliberately fails to compile", "compile_fail"))
                 } else {
                     None
                 };