Reproduce #2156

ui_test/.gitignore

@@ -0,0 +1 @@
+Cargo.lock

ui_test/src/comments.rs

@@ -5,7 +5,7 @@ use regex::Regex;
 /// This crate supports various magic comments that get parsed as file-specific
 /// configuration values. This struct parses them all in one go and then they
 /// get processed by their respective use sites.
-#[derive(Default)]
+#[derive(Default, Debug)]
 pub struct Comments {
     /// List of revision names to execute. Can only be speicified once
     pub revisions: Option<Vec<String>>,
@@ -26,6 +26,7 @@ pub struct Comments {
     pub error_matches: Vec<ErrorMatch>,
 }
 
+#[derive(Debug)]
 pub struct ErrorMatch {
     pub matched: String,
     pub revision: Option<String>,
@@ -33,9 +34,13 @@ pub struct ErrorMatch {
 }
 
 impl Comments {
-    pub fn parse(path: &Path) -> Self {
-        let mut this = Self::default();
+    pub fn parse_file(path: &Path) -> Self {
         let content = std::fs::read_to_string(path).unwrap();
+        Self::parse(path, &content)
+    }
+
+    pub fn parse(path: &Path, content: &str) -> Self {
+        let mut this = Self::default();
         let error_pattern_regex =
             Regex::new(r"//(\[(?P<revision>[^\]]+)\])?~[|^]*\s*(ERROR|HELP|WARN)?:?(?P<text>.*)")
                 .unwrap();

ui_test/src/lib.rs

@@ -9,7 +9,7 @@ use comments::ErrorMatch;
 use crossbeam::queue::SegQueue;
 use regex::Regex;
 
-use crate::comments::Comments;
+pub use crate::comments::Comments;
 
 mod comments;
 
@@ -73,7 +73,7 @@ pub fn run_tests(config: Config) {
                     if !path.extension().map(|ext| ext == "rs").unwrap_or(false) {
                         continue;
                     }
-                    let comments = Comments::parse(&path);
+                    let comments = Comments::parse_file(&path);
                     // Ignore file if only/ignore rules do (not) apply
                     if ignore_file(&comments, &target) {
                         ignored.fetch_add(1, Ordering::Relaxed);
@@ -171,7 +171,7 @@ pub fn run_tests(config: Config) {
 }
 
 #[derive(Debug)]
-enum Error {
+pub enum Error {
     /// Got an invalid exit status for the given mode.
     ExitStatus(Mode, ExitStatus),
     PatternNotFound {
@@ -191,7 +191,7 @@ enum Error {
     },
 }
 
-type Errors = Vec<Error>;
+pub type Errors = Vec<Error>;
 
 fn run_test(
     path: &Path,
@@ -249,7 +249,7 @@ fn run_test(
     (miri, errors)
 }
 
-fn check_annotations(
+pub fn check_annotations(
     unnormalized_stderr: &[u8],
     errors: &mut Errors,
     config: &Config,

ui_test/tests/check_annotations.rs

@@ -0,0 +1,49 @@
+use std::path::{Path, PathBuf};
+
+use ui_test::{check_annotations, Comments, Config, Error, Mode, OutputConflictHandling};
+
+fn config() -> Config {
+    Config {
+        args: vec![],
+        target: None,
+        stderr_filters: vec![],
+        stdout_filters: vec![],
+        root_dir: PathBuf::from("."),
+        mode: Mode::Fail,
+        program: PathBuf::from("cake"),
+        output_conflict_handling: OutputConflictHandling::Error,
+    }
+}
+
+#[test]
+fn issue_2156() {
+    let s = r"
+use std::mem;
+
+fn main() {
+    let _x: &i32 = unsafe { mem::transmute(16usize) }; //~ ERROR encountered a dangling reference (address $HEX is unallocated)
+}
+    ";
+    let comments = Comments::parse(Path::new("<dummy>"), s);
+    let mut errors = vec![];
+    let config = config();
+    let unnormalized_stderr = r"
+error: Undefined Behavior: type validation failed: encountered a dangling reference (address 0x10 is unallocated)
+  --> tests/compile-fail/validity/dangling_ref1.rs:6:29
+   |
+LL |     let _x: &i32 = unsafe { mem::transmute(16usize) }; //~ ERROR encountered a dangling reference (address $HEX is unallocated)
+   |                             ^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered a dangling reference (address 0x10 is unallocated)
+   |
+   = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
+   = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
+           
+   = note: inside `main` at tests/compile-fail/validity/dangling_ref1.rs:6:29
+note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
+error: aborting due to previous error
+    ";
+    check_annotations(unnormalized_stderr.as_bytes(), &mut errors, &config, "", &comments);
+    match &errors[..] {
+        [Error::PatternNotFound { .. }] => {}
+        _ => panic!("{:#?}", errors),
+    }
+}

ui_test/tests/comment_parser.rs

@@ -0,0 +1,22 @@
+use std::path::Path;
+
+use ui_test::Comments;
+
+#[test]
+fn issue_2156() {
+    let s = r"
+use std::mem;
+
+fn main() {
+    let _x: &i32 = unsafe { mem::transmute(16usize) }; //~ ERROR encountered a dangling reference (address $HEX is unallocated)
+}
+    ";
+    let comments = Comments::parse(Path::new("<dummy>"), s);
+    println!("{:#?}", comments);
+    assert_eq!(comments.error_matches[0].definition_line, 4);
+    assert_eq!(comments.error_matches[0].revision, None);
+    assert_eq!(
+        comments.error_matches[0].matched,
+        "encountered a dangling reference (address $HEX is unallocated)"
+    );
+}