Update expect message using the recommended style in binary_heap module by SzilvasiPeter · Pull Request #159821 · rust-lang/rust

SzilvasiPeter · 2026-07-24T08:38:51Z

Related issue: #159751

rustbot · 2026-07-24T08:38:56Z

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fee1-dead · 2026-07-24T18:01:25Z

@Colepng this is related to the file you claimed, sorry for not grouping them together clearly. We will need to use a consistent message across those files

Colepng · 2026-07-25T00:54:06Z

Okay I will use the one from this pr.

Darksonn

@bors r+ rollup

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rust-bors · 2026-07-26T07:23:27Z

📌 Commit 82b5964 has been approved by Darksonn

It is now in the queue for this repository.

🌲 The tree is currently closed for pull requests below priority 100. This pull request will be tested once the tree is reopened.

Reason for tree closure: spurious failures

Update expect message using the recommended style in binary_heap module Related issue: rust-lang#159751

…uwer Rollup of 24 pull requests Successful merges: - #159638 (bootstrap: Split the `Step` trait into multiple traits) - #159774 (rustc_trait_selection: fix trait solver hang caused by degenerate obligations) - #159837 (line-tables-only test: check that the line number matches the function name) - #159946 (Update Enzyme submodule to imporve llvm-cov) - #159617 (Fix up `#[linkage]` target checking) - #159733 (std: Switch implementations of `thread_local!` for WASI) - #159783 (Check unsafe impls on safe EIIs) - #159810 (Add tuple never coercion collection regression test) - #159821 (Update expect message using the recommended style in binary_heap module) - #159826 (Remove redundant `#[rustc_paren_sugar]` feature gate) - #159846 (Implement `str::copy_from_str`) - #159849 (rustc_parse: Stop returning `Option` from statement parsing) - #159853 (Updated expect messages for `CString` struct and method documentation) - #159875 (More cleanup in `rustc_attr_parsing`) - #159882 (Update expect messages in library/alloc/boxed.rs and library/alloc/string.rs to follow the style guide) - #159891 (Split multiline derives into std/rustc macros) - #159893 (Fix `find_attr` hygiene and `rustc_hir` cleanups) - #159895 (rustc-dev-guide subtree update) - #159902 (Clarify that the expected runtime symbols signature is for the current target only) - #159914 (Fix error in diagnostic on_unmatched_args) - #159917 (spare capacity mut constification) - #159918 (rename abort_unwind → abort_on_unwind) - #159936 (Minor `rustc_ast::ast` doc cleanups) - #159945 (Update expect messages in library/core/src/ptr/non_null.rs)

rustbot · 2026-07-26T13:24:26Z

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

rust-bors · 2026-07-26T13:24:29Z

⚠️ A new commit 995e2647b7e78836a26244128d9911fc5d2e3b03 was pushed.

This pull request was unapproved.

This PR was contained in a rollup (#159957), which was closed.

SzilvasiPeter · 2026-07-26T13:39:40Z

@Darksonn I updated the expect message in the vec_deque module, too.

Darksonn

The guidelines you are using are designed for expect() calls where a panic indicates a bug, but for some of these it's expected that they might actually panic for some inputs, so the guideline does not apply.

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Darksonn · 2026-07-26T18:57:17Z

    #[cfg_attr(not(test), rustc_diagnostic_item = "vecdeque_reserve")]
    pub fn reserve(&mut self, additional: usize) {
-        let new_cap = self.len.checked_add(additional).expect("capacity overflow");
+        let new_cap = self.len.checked_add(additional).expect("length should not overflow usize");


This one I don't think we should change. It's an overflow that can actually happen for some user-provided values of additional, so the message shouldn't claim that this will not overflow when it actually can overflow. Instead the message should be tailored to be usefulf for the caller.

I wonder if we should use let else for some of these with an explicit panic rather than expect, since I would rather not want expect to be used for "regular panic"s that just occur due to bad user input.

I'm not sure, but that seems like a bigger change than fixing part of #159751

Darksonn · 2026-07-26T18:57:41Z

    pub fn append(&mut self, other: &mut Self) {
        if T::IS_ZST {
-            self.len = self.len.checked_add(other.len).expect("capacity overflow");
+            self.len = self.len.checked_add(other.len).expect("length should not overflow usize");


Same applies here.

Darksonn · 2026-07-26T18:57:48Z

    #[inline]
    fn index(&self, index: usize) -> &T {
-        self.get(index).expect("Out of bounds access")
+        self.get(index).expect("index should be within bounds")


Darksonn · 2026-07-26T18:57:53Z

    #[inline]
    fn index_mut(&mut self, index: usize) -> &mut T {
-        self.get_mut(index).expect("Out of bounds access")
+        self.get_mut(index).expect("index should be within bounds")


rustbot added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Jul 24, 2026

rustbot assigned Darksonn Jul 24, 2026

rustbot added the T-libs Relevant to the library team, which will review and decide on the PR/issue. label Jul 24, 2026

Darksonn approved these changes Jul 26, 2026

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rust-bors Bot added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Jul 26, 2026

JonathanBrouwer added a commit to JonathanBrouwer/rust that referenced this pull request Jul 26, 2026

Rollup merge of rust-lang#159821 - SzilvasiPeter:main, r=Darksonn

532e546

Update expect message using the recommended style in binary_heap module Related issue: rust-lang#159751

JonathanBrouwer mentioned this pull request Jul 26, 2026

Rollup of 25 pull requests #159952

Closed

JonathanBrouwer added a commit to JonathanBrouwer/rust that referenced this pull request Jul 26, 2026

Rollup merge of rust-lang#159821 - SzilvasiPeter:main, r=Darksonn

3e6377e

Update expect message using the recommended style in binary_heap module Related issue: rust-lang#159751

JonathanBrouwer mentioned this pull request Jul 26, 2026

Rollup of 24 pull requests #159957

Closed

rust-bors Bot added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Jul 26, 2026

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Update expect message using the recommended style in binary_heap module

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SzilvasiPeter force-pushed the main branch from 995e264 to 91cead3 Compare July 26, 2026 13:27

rustbot removed has-merge-commits PR has merge commits, merge with caution. S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Jul 26, 2026

Update expect message in library/alloc/src/collections/vec_deque/mod.rs

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Darksonn reviewed Jul 26, 2026

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Darksonn added the S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. label Jul 26, 2026

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