incr: Update hash tests to use except-style checking

[CrockAgile]

Part of #44924

r? @michaelwoerister

[michaelwoerister]

Thanks a lot, @CrockAgile! Quite a few check boxes to tick off :)

@bors r+

[bors]

📌 Commit 6424688 has been approved by michaelwoerister

[michaelwoerister]

@bors rollup

[kennytm]

@bors r-

This PR failed in the rollup #45981 at incremental/hashes/if_expressions.rs when testing in x86_64-gnu-nopt. I think this has something to do with the += operator which uses checked arithmetic in debug build.

[01:03:13] ---- [incremental] incremental/hashes/if_expressions.rs stdout ----
[01:03:13] 	
[01:03:13] error in revision `cfail2`: test compilation failed although it shouldn't!
[01:03:13] status: exit code: 101
[01:03:13] command: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/src/test/incremental/hashes/if_expressions.rs" "-L" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/incremental" "--target=x86_64-unknown-linux-gnu" "--cfg" "cfail2" "-Z" "incremental=/checkout/obj/build/x86_64-unknown-linux-gnu/test/incremental/hashes/if_expressions.inc" "-Z" "incremental-verify-ich" "--error-format" "json" "-C" "prefer-dynamic" "-o" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/incremental/hashes/if_expressions.stage2-x86_64-unknown-linux-gnu" "-Crpath" "-Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "-Z" "query-dep-graph" "-L" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/incremental/hashes/if_expressions.stage2-x86_64-unknown-linux-gnu.aux"
[01:03:13] stdout:
[01:03:13] ------------------------------------------
[01:03:13] 
[01:03:13] ------------------------------------------
[01:03:13] stderr:
[01:03:13] ------------------------------------------
[01:03:13] {"message":"`MirOptimized(add_else_branch)` should be clean but is not","code":null,"level":"error","spans":[{"file_name":"/checkout/src/test/incremental/hashes/if_expressions.rs","byte_start":2817,"byte_end":2938,"line_start":118,"line_end":127,"column_start":1,"column_end":2,"is_primary":true,"text":[{"text":"pub fn add_else_branch(x: bool) -> u32 {","highlight_start":1,"highlight_end":41},{"text":"    let mut ret = 1;","highlight_start":1,"highlight_end":21},{"text":"","highlight_start":1,"highlight_end":1},{"text":"    if x {","highlight_start":1,"highlight_end":11},{"text":"        ret += 1;","highlight_start":1,"highlight_end":18},{"text":"    } else {","highlight_start":1,"highlight_end":13},{"text":"    }","highlight_start":1,"highlight_end":6},{"text":"","highlight_start":1,"highlight_end":1},{"text":"    ret","highlight_start":1,"highlight_end":8},{"text":"}","highlight_start":1,"highlight_end":2}],"label":null,"suggested_replacement":null,"expansion":null}],"children":[],"rendered":null}
[01:03:13] {"message":"`MirValidated(add_else_branch)` should be clean but is not","code":null,"level":"error","spans":[{"file_name":"/checkout/src/test/incremental/hashes/if_expressions.rs","byte_start":2817,"byte_end":2938,"line_start":118,"line_end":127,"column_start":1,"column_end":2,"is_primary":true,"text":[{"text":"pub fn add_else_branch(x: bool) -> u32 {","highlight_start":1,"highlight_end":41},{"text":"    let mut ret = 1;","highlight_start":1,"highlight_end":21},{"text":"","highlight_start":1,"highlight_end":1},{"text":"    if x {","highlight_start":1,"highlight_end":11},{"text":"        ret += 1;","highlight_start":1,"highlight_end":18},{"text":"    } else {","highlight_start":1,"highlight_end":13},{"text":"    }","highlight_start":1,"highlight_end":6},{"text":"","highlight_start":1,"highlight_end":1},{"text":"    ret","highlight_start":1,"highlight_end":8},{"text":"}","highlight_start":1,"highlight_end":2}],"label":null,"suggested_replacement":null,"expansion":null}],"children":[],"rendered":null}
[01:03:13] {"message":"`MirValidated(add_else_branch_if_let)` should be clean but is not","code":null,"level":"error","spans":[{"file_name":"/checkout/src/test/incremental/hashes/if_expressions.rs","byte_start":4990,"byte_end":5139,"line_start":223,"line_end":232,"column_start":1,"column_end":2,"is_primary":true,"text":[{"text":"pub fn add_else_branch_if_let(x: Option<u32>) -> u32 {","highlight_start":1,"highlight_end":55},{"text":"    let mut ret = 1;","highlight_start":1,"highlight_end":21},{"text":"","highlight_start":1,"highlight_end":1},{"text":"    if let Some(x) = x {","highlight_start":1,"highlight_end":25},{"text":"        ret += x;","highlight_start":1,"highlight_end":18},{"text":"    } else {","highlight_start":1,"highlight_end":13},{"text":"    }","highlight_start":1,"highlight_end":6},{"text":"","highlight_start":1,"highlight_end":1},{"text":"    ret","highlight_start":1,"highlight_end":8},{"text":"}","highlight_start":1,"highlight_end":2}],"label":null,"suggested_replacement":null,"expansion":null}],"children":[],"rendered":null}
[01:03:13] {"message":"`MirOptimized(add_else_branch_if_let)` should be clean but is not","code":null,"level":"error","spans":[{"file_name":"/checkout/src/test/incremental/hashes/if_expressions.rs","byte_start":4990,"byte_end":5139,"line_start":223,"line_end":232,"column_start":1,"column_end":2,"is_primary":true,"text":[{"text":"pub fn add_else_branch_if_let(x: Option<u32>) -> u32 {","highlight_start":1,"highlight_end":55},{"text":"    let mut ret = 1;","highlight_start":1,"highlight_end":21},{"text":"","highlight_start":1,"highlight_end":1},{"text":"    if let Some(x) = x {","highlight_start":1,"highlight_end":25},{"text":"        ret += x;","highlight_start":1,"highlight_end":18},{"text":"    } else {","highlight_start":1,"highlight_end":13},{"text":"    }","highlight_start":1,"highlight_end":6},{"text":"","highlight_start":1,"highlight_end":1},{"text":"    ret","highlight_start":1,"highlight_end":8},{"text":"}","highlight_start":1,"highlight_end":2}],"label":null,"suggested_replacement":null,"expansion":null}],"children":[],"rendered":null}
[01:03:13] {"message":"aborting due to 4 previous errors","code":null,"level":"error","spans":[],"children":[],"rendered":null}
[01:03:13] 
[01:03:13] ------------------------------------------
[01:03:13] 
[01:03:13] thread '[incremental] incremental/hashes/if_expressions.rs' panicked at 'explicit panic', /checkout/src/tools/compiletest/src/runtest.rs:2506:8
[01:03:13] note: Run with `RUST_BACKTRACE=1` for a backtrace.
[01:03:13] 
[01:03:13] 
[01:03:13] failures:
[01:03:13]     [incremental] incremental/hashes/if_expressions.rs
[01:03:13] 
[01:03:13] test result: �[31mFAILED�(B�[m. 81 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out

[CrockAgile]

@kennytm as you say, the checked arithmetic is probably the culprit. From what I can tell, these tests were not intended to check this behavior, and other tests in panci_exprs.rs already do. Should these test functions be changed then so they do not include checked arithmetic, and focus on the addition of an else branch? I'll try removing the checked arithmetic, but if that isn't ideal then I am open to other ideas

[kennytm]

@CrockAgile I prefer to change it to something that doesn't involve checked arithmetic (e.g. ^=), but I'll let @michaelwoerister decide what should be the proper change.

[michaelwoerister]

Thanks, that's the solution I would have proposed too.

@bors r+

[bors]

📌 Commit d1a83c6 has been approved by michaelwoerister