Tweak `if let` suggestion to be more liberal with suggestion and to not ICE #77283

estebank · 2020-09-28T01:59:28Z

Fix #77218. Fix #77238.

rust-highfive · 2020-09-28T01:59:32Z

r? @matthewjasper

(rust_highfive has picked a reviewer for you, use r? to override)

compiler/rustc_typeck/src/check/expr.rs

Dylan-DPC-zz · 2020-10-19T17:53:15Z

r? @Mark-Simulacrum

Mark-Simulacrum · 2020-10-19T21:54:53Z

compiler/rustc_typeck/src/check/expr.rs

-                            Applicability::MaybeIncorrect,
-                        );
-                    }
+            let (mut msg, applicability, eq) = if self.can_coerce(rhs_ty, lhs_ty) {


Hm, so the ordering switched from left/right to right/left here, which (IIRC) with coercion is quite significant. Was that intentional?

Yes, the expression we want to take as "ground truth" to detect if foo = bar when if let foo = bar was meant is the rhs.

estebank · 2020-10-20T01:41:46Z

The ICE is in the beta now.

src/test/ui/issues/issue-77218.stderr

spastorino · 2020-10-22T14:21:39Z

discussed in T-compiler meeting.

@rustbot modify labels: beta-accepted

Of course once approved and merged into master.

Mark-Simulacrum · 2020-10-25T21:49:08Z

Niko indicated that the flip in coercion order was likely fine during the last meeting -- @estebank, would you be up for squashing the commits here a bit? Ideally I'd prefer to avoid 4 commits for such a small and dense change :)

r=me though.

…ot ICE Fix rust-lang#77218. Fix rust-lang#77238.

estebank · 2020-10-25T22:21:46Z

@Mark-Simulacrum done.

Mark-Simulacrum · 2020-10-25T22:51:18Z

@bors r+

Thanks!

bors · 2020-10-25T22:51:20Z

📌 Commit cabf6d0 has been approved by Mark-Simulacrum

…crum Tweak `if let` suggestion to be more liberal with suggestion and to not ICE Fix rust-lang#77218. Fix rust-lang#77238.

bors · 2020-10-26T01:54:00Z

⌛ Testing commit cabf6d0 with merge 16e9ed0...

bors · 2020-10-26T04:34:39Z

☀️ Test successful - checks-actions
Approved by: Mark-Simulacrum
Pushing 16e9ed0 to master...

…ulacrum [beta] backports This backports a number of PRs to beta: * Add delay_span_bug to no longer ICE rust-lang#78645 * Do not ICE on invalid input rust-lang#78422 * revert rust-lang#75443, update mir validator rust-lang#78410 * Do not try to report on closures to avoid ICE rust-lang#78268 * Disable "optimization to avoid load of address" in InstCombine rust-lang#78195 * Disable MatchBranchSimplification rust-lang#78151 * Do not ICE with TraitPredicates containing [type error] rust-lang#77930 * Tweak `if let` suggestion to be more liberal with suggestion and to not ICE rust-lang#77283 * Use different mirror for linux headers in musl-toolchain CI script. rust-lang#78316

…ing, r=petrochenkov Implement destructuring assignment for structs and slices This is the second step towards implementing destructuring assignment (RFC: rust-lang/rfcs#2909, tracking issue: rust-lang#71126). This PR is the second part of rust-lang#71156, which was split up to allow for easier review. Note that the first PR (rust-lang#78748) is not merged yet, so it is included as the first commit in this one. I thought this would allow the review to start earlier because I have some time this weekend to respond to reviews. If `@petrochenkov` prefers to wait until the first PR is merged, I totally understand, of course. This PR implements destructuring assignment for (tuple) structs and slices. In order to do this, the following *parser change* was necessary: struct expressions are not required to have a base expression, i.e. `Struct { a: 1, .. }` becomes legal (in order to act like a struct pattern). Unfortunately, this PR slightly regresses the diagnostics implemented in rust-lang#77283. However, it is only a missing help message in `src/test/ui/issues/issue-77218.rs`. Other instances of this diagnostic are not affected. Since I don't exactly understand how this help message works and how to fix it yet, I was hoping it's OK to regress this temporarily and fix it in a follow-up PR. Thanks to `@varkor` who helped with the implementation, particularly around the struct rest changes. r? `@petrochenkov`

…ing, r=petrochenkov Implement destructuring assignment for structs and slices This is the second step towards implementing destructuring assignment (RFC: rust-lang/rfcs#2909, tracking issue: rust-lang#71126). This PR is the second part of rust-lang#71156, which was split up to allow for easier review. Note that the first PR (rust-lang#78748) is not merged yet, so it is included as the first commit in this one. I thought this would allow the review to start earlier because I have some time this weekend to respond to reviews. If ``@petrochenkov`` prefers to wait until the first PR is merged, I totally understand, of course. This PR implements destructuring assignment for (tuple) structs and slices. In order to do this, the following *parser change* was necessary: struct expressions are not required to have a base expression, i.e. `Struct { a: 1, .. }` becomes legal (in order to act like a struct pattern). Unfortunately, this PR slightly regresses the diagnostics implemented in rust-lang#77283. However, it is only a missing help message in `src/test/ui/issues/issue-77218.rs`. Other instances of this diagnostic are not affected. Since I don't exactly understand how this help message works and how to fix it yet, I was hoping it's OK to regress this temporarily and fix it in a follow-up PR. Thanks to ``@varkor`` who helped with the implementation, particularly around the struct rest changes. r? ``@petrochenkov``

fanzier · 2020-11-13T10:18:17Z

The diagnostics implemented here regressed slightly due to my PR #78836. In the file src/test/ui/issues/issue-77218.rs,

if Some(3) = foo {}

is lowered to

if { let Some(_x) = foo; 3 = _x } {}

Hence the code of this PR doesn't recognize it as something where == or if let should be suggested.

I'm not sure how to best fix this, so pinging @estebank in case he wants to look into this.

estebank · 2020-11-13T22:21:45Z

@fanzier thank you for the heads up :(

…ing, r=petrochenkov Implement destructuring assignment for structs and slices This is the second step towards implementing destructuring assignment (RFC: rust-lang/rfcs#2909, tracking issue: rust-lang#71126). This PR is the second part of rust-lang#71156, which was split up to allow for easier review. Note that the first PR (rust-lang#78748) is not merged yet, so it is included as the first commit in this one. I thought this would allow the review to start earlier because I have some time this weekend to respond to reviews. If ``@petrochenkov`` prefers to wait until the first PR is merged, I totally understand, of course. This PR implements destructuring assignment for (tuple) structs and slices. In order to do this, the following *parser change* was necessary: struct expressions are not required to have a base expression, i.e. `Struct { a: 1, .. }` becomes legal (in order to act like a struct pattern). Unfortunately, this PR slightly regresses the diagnostics implemented in rust-lang#77283. However, it is only a missing help message in `src/test/ui/issues/issue-77218.rs`. Other instances of this diagnostic are not affected. Since I don't exactly understand how this help message works and how to fix it yet, I was hoping it's OK to regress this temporarily and fix it in a follow-up PR. Thanks to ``@varkor`` who helped with the implementation, particularly around the struct rest changes. r? ``@petrochenkov``

rust-highfive assigned matthewjasper Sep 28, 2020

rust-highfive added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Sep 28, 2020

pickfire reviewed Sep 29, 2020

View reviewed changes

compiler/rustc_typeck/src/check/expr.rs Outdated Show resolved Hide resolved

jyn514 added A-diagnostics Area: Messages for errors, warnings, and lints A-suggestion-diagnostics Area: Suggestions generated by the compiler applied by `cargo fix` T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Oct 3, 2020

camelid added the C-bug Category: This is a bug. label Oct 3, 2020

rust-highfive assigned Mark-Simulacrum and unassigned matthewjasper Oct 19, 2020

Mark-Simulacrum reviewed Oct 19, 2020

View reviewed changes

estebank force-pushed the if-let-sugg branch from 9b48500 to 3f3f65d Compare October 20, 2020 01:38

estebank added the beta-nominated Nominated for backporting to the compiler in the beta channel. label Oct 20, 2020

pickfire reviewed Oct 20, 2020

View reviewed changes

src/test/ui/issues/issue-77218.stderr Show resolved Hide resolved

rustbot added the beta-accepted Accepted for backporting to the compiler in the beta channel. label Oct 22, 2020

estebank force-pushed the if-let-sugg branch from b017f31 to 16655ce Compare October 23, 2020 19:17

Tweak if let suggestion to be more liberal with suggestion and to n…

cabf6d0

…ot ICE Fix rust-lang#77218. Fix rust-lang#77238.

estebank force-pushed the if-let-sugg branch from 16655ce to cabf6d0 Compare October 25, 2020 22:21

bors 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 Oct 25, 2020

Dylan-DPC-zz mentioned this pull request Oct 26, 2020

Rollup of 10 pull requests #78383

Closed

Dylan-DPC-zz mentioned this pull request Oct 26, 2020

Rollup of 9 pull requests #78386

Closed

bors added the merged-by-bors This PR was explicitly merged by bors. label Oct 26, 2020

bors mentioned this pull request Oct 26, 2020

Implement destructuring assignment #71156

Closed

bors merged commit 16e9ed0 into rust-lang:master Oct 26, 2020

rustbot added this to the 1.49.0 milestone Oct 26, 2020

Mark-Simulacrum removed the beta-nominated Nominated for backporting to the compiler in the beta channel. label Nov 5, 2020

Mark-Simulacrum modified the milestones: 1.49.0, 1.48.0 Nov 5, 2020

Mark-Simulacrum mentioned this pull request Nov 5, 2020

[beta] backports #78783

Merged

fanzier mentioned this pull request Nov 7, 2020

Implement destructuring assignment for structs and slices #78836

Merged

estebank mentioned this pull request Jan 13, 2021

Confusing errors with missing let in if let #77238

Closed

estebank deleted the if-let-sugg branch November 9, 2023 05:16

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Tweak `if let` suggestion to be more liberal with suggestion and to not ICE #77283

Tweak `if let` suggestion to be more liberal with suggestion and to not ICE #77283

estebank commented Sep 28, 2020

rust-highfive commented Sep 28, 2020

Dylan-DPC-zz commented Oct 19, 2020

Mark-Simulacrum Oct 19, 2020

estebank Oct 20, 2020

estebank commented Oct 20, 2020

spastorino commented Oct 22, 2020

Mark-Simulacrum commented Oct 25, 2020

estebank commented Oct 25, 2020

Mark-Simulacrum commented Oct 25, 2020

bors commented Oct 25, 2020

bors commented Oct 26, 2020

bors commented Oct 26, 2020

fanzier commented Nov 13, 2020

estebank commented Nov 13, 2020

Tweak if let suggestion to be more liberal with suggestion and to not ICE #77283

Tweak if let suggestion to be more liberal with suggestion and to not ICE #77283

Conversation

estebank commented Sep 28, 2020

rust-highfive commented Sep 28, 2020

Dylan-DPC-zz commented Oct 19, 2020

Mark-Simulacrum Oct 19, 2020

Choose a reason for hiding this comment

estebank Oct 20, 2020

Choose a reason for hiding this comment

estebank commented Oct 20, 2020

spastorino commented Oct 22, 2020

Mark-Simulacrum commented Oct 25, 2020

estebank commented Oct 25, 2020

Mark-Simulacrum commented Oct 25, 2020

bors commented Oct 25, 2020

bors commented Oct 26, 2020

bors commented Oct 26, 2020

fanzier commented Nov 13, 2020

estebank commented Nov 13, 2020

Tweak `if let` suggestion to be more liberal with suggestion and to not ICE #77283

Tweak `if let` suggestion to be more liberal with suggestion and to not ICE #77283