clang-format: ColumnLimit:0 breaks lambda formatting

[Quuxplusone]

Bugzilla Link	PR50931
Status	CONFIRMED
Importance	P normal
Reported by	Vadim Kalinnikov (kalinnikov@seaproject.ru)
Reported on	2021-06-29 06:09:22 -0700
Last modified on	2021-07-07 02:16:46 -0700
Version	12.0
Hardware	PC Linux
CC	djasper@google.com, klimek@google.com, llvm-bugs@lists.llvm.org, mydeveloperday@gmail.com
Fixed by commit(s)
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Blocked by
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Setting ColumnLimit to 0 causes clang-format to add an extra line break between
[] and { for a single-line lambda.

---
test.cpp:
int main() {
  std::vector<int> v;
  std::find_if(v.begin(), v.end(), [] {return 1;});
}

---
.clang-format:
BreakBeforeBraces: Custom
BraceWrapping:
  BeforeLambdaBody: true
ColumnLimit: 0

clang-format test.cpp:
int main() {
  std::vector<int> v;
  std::find_if(v.begin(), v.end(), []
               { return 1; });
}

---
.clang-format:
BreakBeforeBraces: Custom
BraceWrapping:
  BeforeLambdaBody: true

clang-format test.cpp:
int main() {
  std::vector<int> v;
  std::find_if(v.begin(), v.end(), [] { return 1; });
}

[Quuxplusone]

I don't know if there is a cause other than that you've said you want to break before the {

also in the documentation it does say

A column limit of 0 means that there is no column limit. In this case, clang-format will respect the input’s line breaking decisions within statements unless they contradict other rules.

Emphasis on the "unless they contradict other rules"

I'm not sure if this classes as one of those other rules

[Quuxplusone]

Such behavior is inconsistent with some other rules.
For functions breaking doesn't happen if I put everything on a single line, so
I reckon neither should it happen for lambdas.

[Quuxplusone]

Maybe looks at AllowShortLambdasOnASingleLine

[Quuxplusone]

Yes, AllowShortLambdasOnASingleLine would fix the issue.