make it possible to test more of ui_test

ui_test/src/lib.rs

@@ -235,11 +235,34 @@ fn run_test(
     }
     let output = miri.output().expect("could not execute miri");
     let mut errors = config.mode.ok(output.status);
+    check_test_result(
+        path,
+        config,
+        target,
+        revision,
+        comments,
+        &mut errors,
+        &output.stdout,
+        &output.stderr,
+    );
+    (miri, errors)
+}
+
+fn check_test_result(
+    path: &Path,
+    config: &Config,
+    target: &str,
+    revision: &str,
+    comments: &Comments,
+    errors: &mut Errors,
+    stdout: &[u8],
+    stderr: &[u8],
+) {
     // Always remove annotation comments from stderr.
     let annotations = Regex::new(r"\s*//~.*").unwrap();
-    let stderr = std::str::from_utf8(&output.stderr).unwrap();
+    let stderr = std::str::from_utf8(stderr).unwrap();
     let stderr = annotations.replace_all(stderr, "");
-    let stdout = std::str::from_utf8(&output.stdout).unwrap();
+    let stdout = std::str::from_utf8(stdout).unwrap();
     // Check output files (if any)
     let revised = |extension: &str| {
         if revision.is_empty() {
@@ -252,7 +275,7 @@ fn run_test(
     check_output(
         &stderr,
         path,
-        &mut errors,
+        errors,
         revised("stderr"),
         target,
         &config.stderr_filters,
@@ -262,7 +285,7 @@ fn run_test(
     check_output(
         &stdout,
         path,
-        &mut errors,
+        errors,
         revised("stdout"),
         target,
         &config.stdout_filters,
@@ -270,8 +293,7 @@ fn run_test(
         comments,
     );
     // Check error annotations in the source against output
-    check_annotations(&stderr, &mut errors, config, revision, comments);
-    (miri, errors)
+    check_annotations(&stderr, errors, config, revision, comments);
 }
 
 fn check_annotations(

ui_test/src/tests.rs

@@ -1,6 +1,6 @@
 use std::path::{Path, PathBuf};
 
-use super::{check_annotations, Comments, Config, Error, Mode, OutputConflictHandling};
+use super::*;
 
 fn config() -> Config {
     Config {
@@ -8,7 +8,7 @@ fn config() -> Config {
         target: None,
         stderr_filters: vec![],
         stdout_filters: vec![],
-        root_dir: PathBuf::from("."),
+        root_dir: PathBuf::from("$RUSTROOT"),
         mode: Mode::Fail,
         path_filter: vec![],
         program: PathBuf::from("cake"),
@@ -25,10 +25,12 @@ fn main() {
     let _x: &i32 = unsafe { mem::transmute(16usize) }; //~ ERROR encountered a dangling reference (address $HEX is unallocated)
 }
     ";
-    let comments = Comments::parse(Path::new("<dummy>"), s);
+    let path = Path::new("$DIR/<dummy>");
+    let comments = Comments::parse(&path, s);
     let mut errors = vec![];
     let config = config();
-    let unnormalized_stderr = r"
+    // Crucially, the intended error string *does* appear in this output, as a quote of the comment itself.
+    let stderr = br"
 error: Undefined Behavior: type validation failed: encountered a dangling reference (address 0x10 is unallocated)
   --> tests/compile-fail/validity/dangling_ref1.rs:6:29
    |
@@ -42,9 +44,10 @@ fn main() {
 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, &mut errors, &config, "", &comments);
+    check_test_result(&path, &config, "", "", &comments, &mut errors, /*stdout*/ br"", stderr);
+    // The "OutputDiffers" is because we cannot open the .rs file
     match &errors[..] {
-        [Error::PatternNotFound { .. }] => {}
+        [Error::OutputDiffers { .. }, Error::PatternNotFound { .. }] => {}
         _ => panic!("not the expected error: {:#?}", errors),
     }
 }