[clang-format] Rework Whitesmiths mode to use line-level values in UnwrappedLineParser

[timwoj]

Summary

This commit removes the old way of handling Whitesmiths mode in favor of just setting the
levels during parsing and letting the formatter handle it from there. It requires a bit of
special-casing during the parsing, but ends up a bit cleaner than before. It also removes
some of switch/case unit tests that don't really make much sense when dealing with
Whitesmiths.

[timwoj]

This fixes https://bugs.llvm.org/show_bug.cgi?id=48569, amongst other things.

[MyDeveloperDay]

clang/unittests/Format/FormatTest.cpp

14885

any reason why this is being removed?

[HazardyKnusperkeks]

clang/lib/Format/TokenAnalyzer.cpp

71 ↗

(On Diff #316099)

Unrelated change (although I think it's good one).

clang/lib/Format/UnwrappedLineParser.h

144–149

A bool parameter for something like that is not very nice. An enum (class) is much nicer.

If one does not know the declaration addUnwrappedLine(false) seems a bit odd, addUnwrappedLine(LineLevel::Keep) looks better. (The naming may be changed.)

clang/unittests/Format/FormatTest.cpp

14706

So until now it has formatted that always wrong?

[timwoj]

clang/lib/Format/TokenAnalyzer.cpp

71 ↗

(On Diff #316099)

Should I split that into a separate commit?

clang/unittests/Format/FormatTest.cpp

14706

Hm, that's a good question. I'll have to think about that one. I guess for Whitesmiths and it's always wanting to indent braces, this should be fixed back to way that it was.

14885

This is an artifact of there not being any sort of actual guide for Whitesmiths. I have it set now to always indent the case labels (and it should just ignore the IndentCaseLabels option entirely, like it does for IndentCaseBlocks). I can certainly fix that option to work again though.

[HazardyKnusperkeks]

clang/lib/Format/TokenAnalyzer.cpp

71 ↗

(On Diff #316099)

In my Opinion that would be the best.

[MyDeveloperDay]

clang/lib/Format/Format.cpp

819 ↗

(On Diff #316099)

I guess its fine to define these defaults here but what if people turn them off in their config what will happen?

clang/unittests/Format/FormatTest.cpp

14885

see the images from D93806: [clang-format] PR48569 clang-format fails to align case label with `switch` with Whitesmith Indentation, you are saying that anyone with bracewrappingsytle of Whitesmith cannot decide if they can or cannot indent case labels?

Could you show me a spec that show Whitesmiths is the other way around?

[timwoj]

clang/lib/Format/UnwrappedLineParser.h

144–149

Noted, I'll make it an enum in the next update.

clang/unittests/Format/FormatTest.cpp

14885

Part of the problem is that there isn't any sort of official spec for Whitesmiths that I've been able to find. I'm working on a project that uses it, and have been basically going off their layout as the proper way of doing things. Looking at those images, I agree that the option should continue to function.

[timwoj]

Updates from review:

• Fixed handling of IndentCaseLabels
• Fixed indentation of namespace braces
• Replaced bool argument to addUnwrappedLine with an enum

[timwoj]

Fixing diff to look at the right commit

[HazardyKnusperkeks]

Is there a test with indentation within a namespace? If not maybe you should add one.

clang/lib/Format/UnwrappedLineParser.cpp

614

Maybe give !AddLevel && Style.BreakBeforeBraces == FormatStyle::BS_Whitesmiths a name? You check it three times.

clang/lib/Format/UnwrappedLineParser.h

147

I would prefer an enum class.

[timwoj]

Add tests for Whitesmiths with all of the NamespaceIndentation options

[MyDeveloperDay]

clang/unittests/Format/FormatTest.cpp

14726

you are removing the test with 1 namespace nesting

[timwoj]

Restored lost single-nesting namespace test

[MyDeveloperDay]

LGTM I think, it would be good to get input from other reviewers

clang/unittests/Format/FormatTest.cpp

14874

whilst I don't really like changing the indentation I don't think there was anything that says it was correct before.

[curdeius]

clang/lib/Format/UnwrappedLineParser.cpp

614

Agree on this.

2148

Nit: please write consistently Whitesmiths with a capital W.

2152

3*true? Please add comments a minima.

2254

Nit: full stop at the end of the phrase.

2962

Please move below to the place of use. Also, just naming it ClosesBlock is a bit misleading as it is only for Whitesmiths style.

clang/unittests/Format/FormatTest.cpp

14866

Hmm, you don't test the same thing anymore...

14874

That is really strange that case is indented differently than break. Is it intended? Is the style really like this?

[curdeius]

clang/unittests/Format/FormatTest.cpp

14874

Forget it. I was thinking about something else.

[timwoj]

clang/lib/Format/UnwrappedLineParser.cpp

2962

I agree with renaming it, but I'm not sure on moving it to where it's used. It relies on Line->MatchingOpeningBlockLineIndex which is reset shortly after this boolean value is calculated.

clang/unittests/Format/FormatTest.cpp

14866

This change was intentional. According to the clang-format documentation, IndentCaseBlocks effectively just changes the brace breaking for the block after a case label. Given that it always breaks for Whitesmiths, IndentCaseBlocks can be effectively ignored for that style. I changed it to test the IndentCaseLabels instead because that tests indentation for the whole block.

[timwoj]

• Make LineLevel an enum class
• Combine multiple duplicate checks into a named variable
• Minor formatting fixes

[curdeius]

LGTM. Thanks for working on this.

clang/lib/Format/UnwrappedLineParser.cpp

2962

Right. I've overseen it. It's good now.

[timwoj]

No problem, sorry it took a bit of back-and-forth there. Is there any way this can sneak into 12.0?

[curdeius]

I don't think it can go into 12.x. But if you have a good reason and a related bug report you might add this bug ticket as a release blocker of https://llvm.org/PR48902.

BTW, would you mind updating clang/docs/ReleaseNotes.rst?

[timwoj]

https://bugs.llvm.org/show_bug.cgi?id=48668 already exists as a bug report linked to this review. I'm not sure "the Zeek project would like to start using this" is a good enough reason to block an LLVM release though. I'm fairly certain there aren't a whole lot of people in the world using Whitesmiths. That said, there's already at least one clang-format bug in the release-blocker list.

I'll get the release notes updated shortly.

[MyDeveloperDay]

My advice leave it out of the release, the next release comes round pretty quickly. This gives us 6 months of people who use the snapshots to iron out any issues.

[timwoj]

Added release note entry

[HazardyKnusperkeks]

Have you rebased your change? It seems that your release notes are still for LLVM 12.

[timwoj]

Rebased on main

[HazardyKnusperkeks]

Do you need someone to push this?

[timwoj]

In D94500#2592448, @HazardyKnusperkeks wrote:

Do you need someone to push this?

Yes I do. I don't have committer access.

[HazardyKnusperkeks]

In D94500#2593229, @timwoj wrote:

In D94500#2592448, @HazardyKnusperkeks wrote:

Do you need someone to push this?

Yes I do. I don't have committer access.

Please state the name and mail for the commit.

[timwoj]

In D94500#2594394, @HazardyKnusperkeks wrote:

In D94500#2593229, @timwoj wrote:

In D94500#2592448, @HazardyKnusperkeks wrote:

Do you need someone to push this?

Yes I do. I don't have committer access.

Please state the name and mail for the commit.

Tim Wojtulewicz
[e-mail]