diff options
| author | bors <bors@rust-lang.org> | 2020-10-29 01:37:49 +0000 |
|---|---|---|
| committer | bors <bors@rust-lang.org> | 2020-10-29 01:37:49 +0000 |
| commit | f9187adaef2005b903f666bf323ac675cadf8407 (patch) | |
| tree | e688da00c25304fc6ce9a68a365a98c3eb24155a /src | |
| parent | 31ee872db5aae4750e3da1ca4ed1523c4356947f (diff) | |
| parent | 41a74ace4aeba292ac524dccaa594c2c8aeb19c0 (diff) | |
Auto merge of #78430 - Nadrieril:taking-constructors-seriously2, r=varkor
Clarify main code paths in exhaustiveness checking This PR massively clarifies the main code paths of exhaustiveness checking, by using the `Constructor` enum to a fuller extent. I've been itching to write it for more than a year, but the complexity of matching consts had prevented me. Behold a massive simplification :D. This in particular removes a fair amount of duplication between various parts, localizes code into methods of relevant types when applicable, makes some implicit assumptions explicit, and overall improves legibility a lot (or so I hope). Additionally, after my changes undoing #76918 turned out to be a noticeable perf gain. As usual I tried my best to make the commits self-contained and easy to follow. I've also tried to keep the code well-commented, but I tend to forget how complex this file is; I'm happy to clarify things as needed. My measurements show good perf improvements on the two match-heavy benchmarks (-18.0% on `unicode_normalization-check`! :D); I'd like a perf run to check the overall impact. r? `@varkor` `@rustbot` modify labels: +A-exhaustiveness-checking
Diffstat (limited to 'src')
| -rw-r--r-- | src/test/ui/issues/issue-30240.rs | 4 | ||||
| -rw-r--r-- | src/test/ui/issues/issue-30240.stderr | 8 |
2 files changed, 6 insertions, 6 deletions
diff --git a/src/test/ui/issues/issue-30240.rs b/src/test/ui/issues/issue-30240.rs index a0c0d1626ec..8075532c37d 100644 --- a/src/test/ui/issues/issue-30240.rs +++ b/src/test/ui/issues/issue-30240.rs @@ -1,9 +1,9 @@ fn main() { - match "world" { //~ ERROR non-exhaustive patterns: `&_` + match "world" { //~ ERROR non-exhaustive patterns: `_` "hello" => {} } - match "world" { //~ ERROR non-exhaustive patterns: `&_` + match "world" { //~ ERROR non-exhaustive patterns: `_` ref _x if false => {} "hello" => {} } diff --git a/src/test/ui/issues/issue-30240.stderr b/src/test/ui/issues/issue-30240.stderr index a2c58d6e051..71a8bcb50cd 100644 --- a/src/test/ui/issues/issue-30240.stderr +++ b/src/test/ui/issues/issue-30240.stderr @@ -1,17 +1,17 @@ -error[E0004]: non-exhaustive patterns: `&_` not covered +error[E0004]: non-exhaustive patterns: `_` not covered --> $DIR/issue-30240.rs:2:11 | LL | match "world" { - | ^^^^^^^ pattern `&_` not covered + | ^^^^^^^ pattern `_` not covered | = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms = note: the matched value is of type `&str` -error[E0004]: non-exhaustive patterns: `&_` not covered +error[E0004]: non-exhaustive patterns: `_` not covered --> $DIR/issue-30240.rs:6:11 | LL | match "world" { - | ^^^^^^^ pattern `&_` not covered + | ^^^^^^^ pattern `_` not covered | = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms = note: the matched value is of type `&str` |