Actuall run examples in CI and fix them

Author: oli-obk

examples/rustc_basic.rs

@@ -4,6 +4,7 @@ use std::sync::atomic::Ordering;
 use ui_test::{run_tests, Config};
 
 #[cfg(feature = "rustc")]
+#[cfg_attr(test, test)]
 fn main() -> ui_test::color_eyre::Result<()> {
     let config = Config::rustc("examples_tests/rustc_basic");
     let abort_check = config.abort_check.clone();

examples_tests/rustc_basic/aux_derive.stderr

@@ -20,12 +20,14 @@ error[E0384]: cannot assign twice to immutable variable `x`
  --> examples_tests/rustc_basic/aux_derive.rs:8:5
   |
 7 |     let x = Foo;
-  |         -
-  |         |
-  |         first assignment to `x`
-  |         help: consider making this binding mutable: `mut x`
+  |         - first assignment to `x`
 8 |     x = Foo;
   |     ^^^^^^^ cannot assign twice to immutable variable
+  |
+help: consider making this binding mutable
+  |
+7 |     let mut x = Foo;
+  |         +++
 
 error: aborting due to 1 previous error; 2 warnings emitted
 

examples_tests/rustc_basic/filtered_out.rs

@@ -1,4 +1,4 @@
-//@[foo] only-target-asdfasdf
+//@[foo] only-target: asdfasdf
 
 //@ revisions: foo bar