1 files changed, 66 insertions, 0 deletions
diff --git a/tests/run-make/coverage/abort.rs b/tests/run-make/coverage/abort.rs
new file mode 100644
index 00000000000..3dac43df8f3
--- /dev/null
+++ b/tests/run-make/coverage/abort.rs
@@ -0,0 +1,66 @@
+#![feature(c_unwind)]
+#![allow(unused_assignments)]
+
+extern "C" fn might_abort(should_abort: bool) {
+    if should_abort {
+        println!("aborting...");
+        panic!("panics and aborts");
+    } else {
+        println!("Don't Panic");
+    }
+}
+
+fn main() -> Result<(), u8> {
+    let mut countdown = 10;
+    while countdown > 0 {
+        if countdown < 5 {
+            might_abort(false);
+        }
+        // See discussion (below the `Notes` section) on coverage results for the closing brace.
+        if countdown < 5 { might_abort(false); } // Counts for different regions on one line.
+        // For the following example, the closing brace is the last character on the line.
+        // This shows the character after the closing brace is highlighted, even if that next
+        // character is a newline.
+        if countdown < 5 { might_abort(false); }
+        countdown -= 1;
+    }
+    Ok(())
+}
+
+// Notes:
+//   1. Compare this program and its coverage results to those of the similar tests
+//      `panic_unwind.rs` and `try_error_result.rs`.
+//   2. This test confirms the coverage generated when a program includes `TerminatorKind::Abort`.
+//   3. The test does not invoke the abort. By executing to a successful completion, the coverage
+//      results show where the program did and did not execute.
+//   4. If the program actually aborted, the coverage counters would not be saved (which "works as
+//      intended"). Coverage results would show no executed coverage regions.
+//   6. If `should_abort` is `true` and the program aborts, the program exits with a `132` status
+//      (on Linux at least).
+
+/*
+
+Expect the following coverage results:
+
+```text
+    16|     11|    while countdown > 0 {
+    17|     10|        if countdown < 5 {
+    18|      4|            might_abort(false);
+    19|      6|        }
+```
+
+This is actually correct.
+
+The condition `countdown < 5` executed 10 times (10 loop iterations).
+
+It evaluated to `true` 4 times, and executed the `might_abort()` call.
+
+It skipped the body of the `might_abort()` call 6 times. If an `if` does not include an explicit
+`else`, the coverage implementation injects a counter, at the character immediately after the `if`s
+closing brace, to count the "implicit" `else`. This is the only way to capture the coverage of the
+non-true condition.
+
+As another example of why this is important, say the condition was `countdown < 50`, which is always
+`true`. In that case, we wouldn't have a test for what happens if `might_abort()` is not called.
+The closing brace would have a count of `0`, highlighting the missed coverage.
+*/