Use clang-format for code formatting

[zamazan4ik]

For fixing I used clang-format -i -style=Google **/.h && clang-format -i -style=Google **/.cpp

clang-format 6.0.0

In this PR I suggest to discuss about code-style for Tesseract. Because FMPOV Google style isn't ideal for Tesseract and we can add some Tesseract-specific options.

[amitdo]

#848 (comment)
#854

[stweil]

Why is https://github.com/stweil/tesseract/tree/format different?

[Shreeshrii]

#1598 is using clang-format 6.0.0

https://github.com/stweil/tesseract/tree/format is formatted using
clang-format-7

[stweil]

I now created https://github.com/stweil/tesseract/tree/clang-format-6 with clang-format 6.0.0-3. The result is identical to that from clang-format 7.0.0 (that means not the same as https://github.com/ZaMaZaN4iK/tesseract/tree/fix_format). It needs three iterations to stabilize. The formatting was done on Debian Buster.

[stweil]

https://github.com/stweil/tesseract/tree/clang-format-4 and https://github.com/stweil/tesseract/tree/clang-format-5 give different results.

[amitdo]

Run with clang 5 and 6/7:

clang-format -style=google -dump-config > .clang-format

Do you get the same result?

[amitdo]

Appveyor failed.
It doesn't like the openmp formatting in lstm.cpp.

[stweil]

Appveyor fails in my four tests, too. stweil@4ee0fdc shows the dumped configurations.

[stweil]

The Google style does not say whether type *variable or type* variable should be used. It only says that there should not be both variants in the same file. I suggest to use the same variant everywhere. Personally I prefer the first one, but using only the second one would also be fine. What do you think?

[amitdo]

I suggest to use the same variant everywhere.

👍

type *variable vs. type* variable

Personally I prefer the first one, but using only the second one would also be fine. What do you think?

It seems that Ray prefers type* variable (it's also my favorite style).
c1c1e42#diff-f5c88d7e2ff4fc9424ae517ce7b4e1a6

[zamazan4ik]

@amitdo I also prefer type* variable

[zamazan4ik]

I think we should dump existing one format profile (suggest use Google code style), correct it a little bit and push to Tesseract repo

[stweil]

https://github.com/stweil/tesseract/tree/format now uses uniform left aligned pointers and also includes a .clang-format file. Still missing: build fix for Appveyor.

[stweil]

We still have to decide when to do the formatting with clang-format. Should we do it before or after 4.0.0?

[zdenop]

If yes, than we should do it before 4.0 release.

[johnson73A]

it is good

[zdenop]

@zamazan4ik , @stweil : Can be this PR fixed / replaced / closed this week?

[stweil]

Yes, it can be closed. I think we won't reformat the whole code for 4.0.0.

[amitdo]

I suggest to re-format the whole codebase for 5.0.0.

[amitdo]

First step - reformat all headers in 'include/tesseract'.