x.py ignores config.toml's debug-assertions-std for unit tests

[ssomers]

If you have in your config.toml file (or whichever file --config says), only this change to config.toml.example:

debug-assertions-std = true

debug assertions in src/liballoc or library/alloc used to be armed. Since #73374, debug assertions only go off if you also turn on debug. EDIT: since some point, even that doesn't help.

[jyn514]

@ssomers I can't reproduce. I added this assert:

diff --git a/library/core/tests/iter/traits/iterator.rs b/library/core/tests/iter/traits/iterator.rs
index 422e389e380..77e1effc764 100644
--- a/library/core/tests/iter/traits/iterator.rs
+++ b/library/core/tests/iter/traits/iterator.rs
@@ -26,6 +26,7 @@ fn cmp(&self, other: &Self) -> core::cmp::Ordering {
 
 #[test]
 fn test_lt() {
+    debug_assert!(false);
     let empty: [isize; 0] = [];
     let xs = [1, 2, 3];
     let ys = [1, 2, 0];

and set debug = false and debug-assertions-std = true, and got an assertion failure as expected.

Are you expecting assertions to run in coretests maybe?

[ssomers]

Not exactly sure what I was doing back then, nor what you mean with running in coretests. Today, I'd expect, for instance when
adding to library/alloc/src/collections/btree/node/tests.rs:

#[test]
fn test_assert() {
    assert!(false)
}

#[test]
fn test_debug_assert() {
    debug_assert!(false)
}

and running python x.py test library/alloc --no-doc, that both new test cases fail. What I'm seeing is that the debug_assert doesn't even fail when enabling debug, debug-assertions and debug-assertions-std in config.toml.

[jyn514]

@ssomers I'm still not able to replicate this. I ran x test library/alloc --stage 0 --test-args debug_assert with your test case added and the test failed appropriately:

Testing alloc stage0 (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
   Compiling getrandom v0.1.14
   Compiling ppv-lite86 v0.2.8
   Compiling rand_core v0.5.1
   Compiling rand_chacha v0.2.2
   Compiling rand_xorshift v0.2.0
   Compiling rand v0.7.3
   Compiling alloc v0.0.0 (/home/joshua/src/rust/rust/library/alloc)
    Finished release [optimized + debuginfo] target(s) in 1m 15s
     Running unittests (build/x86_64-unknown-linux-gnu/stage0-std/x86_64-unknown-linux-gnu/release/deps/alloc-cd5eecf891e8cfac)

running 1 test
F
failures:

---- collections::btree::node::tests::test_debug_assert stdout ----
thread 'collections::btree::node::tests::test_debug_assert' panicked at 'assertion failed: false', library/alloc/src/collections/btree/node/tests.rs:106:5

[ssomers]

Well, I can still replicate it… on the master at the time. I located the fix at auto merge #90042 (25 October).

And it's really flawless now. The debug assertions detonate if debug or debug-assertions-std is true, or both, and you don't need to clean anything before building to see it.