Add tests for modifying lint levels for lints reported at expansion time

Author: petrochenkov

src/test/ui/lint/expansion-time-include.rs

@@ -0,0 +1,4 @@
+// ignore-test auxiliary file for expansion-time.rs
+
+1
+2

src/test/ui/lint/expansion-time.rs

@@ -0,0 +1,23 @@
+// check-pass
+
+#[warn(meta_variable_misuse)]
+macro_rules! foo {
+    ( $($i:ident)* ) => { $($i)+ }; //~ WARN meta-variable repeats with different Kleene operator
+}
+
+#[warn(missing_fragment_specifier)]
+macro_rules! m { ($i) => {} } //~ WARN missing fragment specifier
+                              //~| WARN this was previously accepted
+
+#[warn(soft_unstable)]
+mod benches {
+    #[bench] //~ WARN use of unstable library feature 'test'
+             //~| WARN this was previously accepted
+    fn foo() {}
+}
+
+#[warn(incomplete_include)]
+fn main() {
+    // WARN see in the stderr file, the warning points to the included file.
+    include!("expansion-time-include.rs");
+}

src/test/ui/lint/expansion-time.stderr

@@ -0,0 +1,56 @@
+warning: meta-variable repeats with different Kleene operator
+  --> $DIR/expansion-time.rs:5:29
+   |
+LL |     ( $($i:ident)* ) => { $($i)+ };
+   |                  -          ^^ - conflicting repetition
+   |                  |
+   |                  expected repetition
+   |
+note: the lint level is defined here
+  --> $DIR/expansion-time.rs:3:8
+   |
+LL | #[warn(meta_variable_misuse)]
+   |        ^^^^^^^^^^^^^^^^^^^^
+
+warning: missing fragment specifier
+  --> $DIR/expansion-time.rs:9:19
+   |
+LL | macro_rules! m { ($i) => {} }
+   |                   ^^
+   |
+note: the lint level is defined here
+  --> $DIR/expansion-time.rs:8:8
+   |
+LL | #[warn(missing_fragment_specifier)]
+   |        ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #40107 <https://github.com/rust-lang/rust/issues/40107>
+
+warning: use of unstable library feature 'test': `bench` is a part of custom test frameworks which are unstable
+  --> $DIR/expansion-time.rs:14:7
+   |
+LL |     #[bench]
+   |       ^^^^^
+   |
+note: the lint level is defined here
+  --> $DIR/expansion-time.rs:12:8
+   |
+LL | #[warn(soft_unstable)]
+   |        ^^^^^^^^^^^^^
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #64266 <https://github.com/rust-lang/rust/issues/64266>
+
+warning: include macro expected single expression in source
+  --> $DIR/expansion-time-include.rs:4:1
+   |
+LL | 2
+   | ^
+   |
+note: the lint level is defined here
+  --> $DIR/expansion-time.rs:19:8
+   |
+LL | #[warn(incomplete_include)]
+   |        ^^^^^^^^^^^^^^^^^^
+
+warning: 4 warnings emitted
+