suggest `!` for erroneous identifier `not` #49258

zackmdavis · 2018-03-22T05:46:11Z

This supersedes #48858.

petrochenkov · 2018-03-22T09:44:40Z

src/libsyntax/parse/parser.rs

+                    let mut err = self.diagnostic()
+                        .struct_span_err(self.span,
+                                         &format!("unexpected {} after identifier",
+                                                  found.to_string()));


You can use format!("unexpected {} after identifier", self.this_token_descr()) here.

petrochenkov · 2018-03-22T09:46:30Z

src/libsyntax/parse/parser.rs

+                // but as `rustc`-the-compiler, we can issue clever diagnostics
+                // for confused users who really want to say `!`
+                let token_cannot_continue_expr = |t: &token::Token| match *t {
+                    // These tokens can't continue an expression after an ident


Comment nit: Tokens that can start an expression after !, but can't continue an expression after an ident

petrochenkov · 2018-03-22T09:47:26Z

src/libsyntax/parse/parser.rs

+                // for confused users who really want to say `!`
+                let token_cannot_continue_expr = |t: &token::Token| match *t {
+                    // These tokens can't continue an expression after an ident
+                    token::Ident(..) | token::Literal(..) | token::Pound => true,


Also, it should be easier now to add the Nt variants from #48858 (comment)

Also, for token::Ident the correct condition is t is Token(ident) && ident_can_begin_expr(ident)

petrochenkov · 2018-03-22T09:52:31Z

Meta: opening a new PR moves it into the end of @bors queue, it's usually better to rework an original PR, then it will land sooner.

shepmaster · 2018-03-30T19:12:45Z

Ping from triage, @zackmdavis ! It's been a week since we heard from you; will you be able to address the review feedback you've received?

zackmdavis · 2018-03-30T19:18:26Z

@shepmaster yes, but next week; very busy lately

zackmdavis · 2018-04-06T06:00:32Z

updated to address feedback, except that I don't know how to write a test example that exercises the nonterminals (and it's more efficient to push this and admit that I don't know if I can't spare the effort to figure it out myself now)

Meta: opening a new PR moves it into the end of @bors queue, it's usually better to rework an original PR, then it will land sooner.

I usually add commits or force-push existing PRs, but in this case, I don't think there are any lines of code in common between the original submission and the post-reviewer-feedback version; semantically, it feels like a "different PR addressing the same issue" rather than "a revision of the same PR". For something nonessential like this, I'm not that interested in jostling for position in the buildbot queue: that's a zero-sum game among outstanding PRs!

TimNN · 2018-04-06T06:36:21Z

Your PR failed on Travis. Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

Resolving deltas: 100% (612068/612068), completed with 4858 local objects.
---
[00:00:41] configure: rust.quiet-tests     := True
---
[00:38:41] ..........................................................................i.........................
[00:38:47] .................i......................................F...........................................
---
[00:39:20] ...............................................................................................i....
[00:39:27] .....................................................................i..............................
---
[00:39:48] ---- [ui] ui/did_you_mean/issue-46836-identifier-not-instead-of-negation.rs stdout ----
[00:39:48]
[00:39:48] error: /checkout/src/test/ui/did_you_mean/issue-46836-identifier-not-instead-of-negation.rs:13: unexpected error: '13:12: 13:19: unexpected `for_you` after identifier'
[00:39:48]
[00:39:48] error: /checkout/src/test/ui/did_you_mean/issue-46836-identifier-not-instead-of-negation.rs:21: unexpected error: '21:15: 21:24: unexpected `the_worst` after identifier'
[00:39:48]
[00:39:48] error: /checkout/src/test/ui/did_you_mean/issue-46836-identifier-not-instead-of-negation.rs:30: unexpected error: '30:9: 30:16: unexpected `println` after identifier'
[00:39:48]
[00:39:48] error: /checkout/src/test/ui/did_you_mean/issue-46836-identifier-not-instead-of-negation.rs:42: unexpected error: '42:27: 42:50: unexpected `be_smothered_out_before` after identifier'
[00:39:48]
[00:39:48] error: /checkout/src/test/ui/did_you_mean/issue-46836-identifier-not-instead-of-negation.rs:13: expected error not found: unexpected identifier after identifier
[00:39:48]
[00:39:48] error: /checkout/src/test/ui/did_you_mean/issue-46836-identifier-not-instead-of-negation.rs:21: expected error not found: unexpected identifier after identifier
[00:39:48]
[00:39:48] error: /checkout/src/test/ui/did_you_mean/issue-46836-identifier-not-instead-of-negation.rs:30: expected error not found: unexpected identifier after identifier
[]         line_num: 30,
[00:39:48]         kind: Some(
[00:39:48]             Error
[00:39:48]         ),
[00:39:48]         msg: "30:9: 30:16: unexpected `println` after identifier"
---
[00:39:48]         msg: "42:27: 42:50: unexpected `be_smothered_out_before` after identifier"
---
[00:39:48]         msg: "unexpected identifier after identifier"
---
[00:39:48]         msg: "unexpected identifier after identifier"
---
[00:39:48]         msg: "unexpected identifier after identifier"
---
[00:39:48]         msg: "unexpected identifier after identifier"
[00:39:48]     }
[00:39:48] ]
[00:39:48]
[00:39:48] thread '[ui] ui/did_you_mean/issue-46836-identifier-not-instead-of-negation.rs' panicked at 'explicit panic', tools/compiletest/src/runtest.rs:1253:13
[00:39:48] note: Run with `RUST_BACKTRACE=1` for a backtrace.
[00:39:48]
[00:39:48]
[00:39:48] failures:
[00:39:48]     [ui] ui/did_you_mean/issue-46836-identifier-not-instead-of-negation.rs
---
[00:39:48] command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools-bin/compiletest" "--compile-lib-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib" "--run-lib-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib/rustlib/x86_64-unknown-linux-gnu/lib" "--rustc-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "--src-base" "/checkout/src/test/ui" "--build-base" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui" "--stage-id" "stage2-x86_64-unknown-linux-gnu" "--mode" "ui" "--target" "x86_64-unknown-linux-gnu" "--host" "x86_64-unknown-linux-gnu" "--llvm-filecheck" "/usr/lib/llvm-3.9/bin/FileCheck" "--host-rustcflags" "-Crpath -O -Zmiri -Zunstable-options " "--target-rustcflags" "-Crpath -O -Zmiri -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--docck-python" "/usr/bin/python2.7" "--lldb-python" "/usr/bin/python2.7" "--gdb" "/usr/bin/gdb" "--quiet" "--llvm-version" "3.9.1\n" "--system-llvm" "--cc" "" "--cxx" "" "--cflags" "" "--llvm-components" "" "--llvm-cxxflags" "" "--adb-path" "adb" "--adb-test-dir" "/data/tmp/work" "--android-cross-path" "" "--color" "alwa3696680 .

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN.

petrochenkov · 2018-04-06T09:07:18Z

r=me after making Travis green (updating UI tests)

Thanks to the inestimably inimitable Esteban "Estebank" Küber for pointing this out. This is relevant to rust-lang#46836.

Impressing confused Python users with magical diagnostics is perhaps worth this not-grossly-unreasonable (only 40ish lines) extra complexity in the parser? Thanks to Vadim Petrochenkov for guidance. This resolves rust-lang#46836.

zackmdavis · 2018-04-09T15:48:40Z

(I wish the check for //~-expected errors ran anyway even if the stderr file didn't match; it's too easy to update the latter and forget about the former.)

petrochenkov · 2018-04-09T17:27:58Z

@bors r+

bors · 2018-04-09T17:27:59Z

📌 Commit ba0dd8e has been approved by petrochenkov

bors · 2018-04-09T18:40:38Z

⌛ Testing commit ba0dd8e with merge 6f0cad9687f69e5dbb3a643515a419997bc50912...

bors · 2018-04-09T21:41:06Z

💔 Test failed - status-appveyor

zackmdavis · 2018-04-09T21:58:16Z

Three-hour timeout on 64-bit Windows??

petrochenkov · 2018-04-10T01:29:36Z

@bors retry

bors · 2018-04-10T03:27:50Z

⌛ Testing commit ba0dd8e with merge 5d7f892...

@petrochenkov

suggest `!` for erroneous identifier `not` ![not_recovery](https://user-images.githubusercontent.com/1076988/37753255-3b669c42-2d59-11e8-9071-efad8eaf3086.png) This supersedes #48858. r? @petrochenkov

bors · 2018-04-10T06:23:47Z

☀️ Test successful - status-appveyor, status-travis
Approved by: petrochenkov
Pushing 5d7f892 to master...

rust-highfive assigned petrochenkov Mar 22, 2018

rust-highfive added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Mar 22, 2018

zackmdavis mentioned this pull request Mar 22, 2018

suggest ! instead of erroneous not on if/while block parse failure #48858

Closed

petrochenkov reviewed Mar 22, 2018

View reviewed changes

petrochenkov 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-review Status: Awaiting review from the assignee but also interested parties. labels Mar 22, 2018

zackmdavis mentioned this pull request Mar 30, 2018

also point to value in "value assigned is never read" lint #49197

Closed

zackmdavis force-pushed the not_going_to_recover branch from be654c3 to cea7c69 Compare April 6, 2018 05:54

zackmdavis added 2 commits April 9, 2018 08:45

don't suggest placing code in block if next token is open-brace

944c401

Thanks to the inestimably inimitable Esteban "Estebank" Küber for pointing this out. This is relevant to rust-lang#46836.

in which ! is suggested for erroneous identifier not

ba0dd8e

Impressing confused Python users with magical diagnostics is perhaps worth this not-grossly-unreasonable (only 40ish lines) extra complexity in the parser? Thanks to Vadim Petrochenkov for guidance. This resolves rust-lang#46836.

zackmdavis force-pushed the not_going_to_recover branch from cea7c69 to ba0dd8e Compare April 9, 2018 15:46

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-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Apr 9, 2018

bors added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Apr 9, 2018

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 Apr 10, 2018

bors merged commit ba0dd8e into rust-lang:master Apr 10, 2018

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

suggest `!` for erroneous identifier `not` #49258

suggest `!` for erroneous identifier `not` #49258

zackmdavis commented Mar 22, 2018

petrochenkov Mar 22, 2018

petrochenkov Mar 22, 2018

petrochenkov Mar 22, 2018

petrochenkov Mar 22, 2018

petrochenkov commented Mar 22, 2018

shepmaster commented Mar 30, 2018

zackmdavis commented Mar 30, 2018

zackmdavis commented Apr 6, 2018

TimNN commented Apr 6, 2018

petrochenkov commented Apr 6, 2018

zackmdavis commented Apr 9, 2018

petrochenkov commented Apr 9, 2018

bors commented Apr 9, 2018

bors commented Apr 9, 2018

bors commented Apr 9, 2018

zackmdavis commented Apr 9, 2018

petrochenkov commented Apr 10, 2018

bors commented Apr 10, 2018

bors commented Apr 10, 2018

suggest ! for erroneous identifier not #49258

suggest ! for erroneous identifier not #49258

Conversation

zackmdavis commented Mar 22, 2018

petrochenkov Mar 22, 2018

Choose a reason for hiding this comment

petrochenkov Mar 22, 2018

Choose a reason for hiding this comment

petrochenkov Mar 22, 2018

Choose a reason for hiding this comment

petrochenkov Mar 22, 2018

Choose a reason for hiding this comment

petrochenkov commented Mar 22, 2018

shepmaster commented Mar 30, 2018

zackmdavis commented Mar 30, 2018

zackmdavis commented Apr 6, 2018

TimNN commented Apr 6, 2018

petrochenkov commented Apr 6, 2018

zackmdavis commented Apr 9, 2018

petrochenkov commented Apr 9, 2018

bors commented Apr 9, 2018

bors commented Apr 9, 2018

bors commented Apr 9, 2018

zackmdavis commented Apr 9, 2018

petrochenkov commented Apr 10, 2018

bors commented Apr 10, 2018

bors commented Apr 10, 2018

suggest `!` for erroneous identifier `not` #49258

suggest `!` for erroneous identifier `not` #49258