[FR] Coding style checker and workflow integration

[fujitatomoya]

Feature request

Motivation

follow up of #20.
coding style needs to be checked by every single PR and commits to make sure incoming PRs are compatible with current development policy.

Feature description

We can rely on cpplint, and integrate it to github workflow.

[Windrow14]

Commands to be added in the pipeline:

pip install cpplint
find -iname *.h | xargs cpplint
find -iname *.c | xargs cpplint
find -iname *.hpp | xargs cpplint
find -iname *.cpp | xargs cpplint

However, cpplint is just a static code checker. It does not modify code automatically by itself. We need to modify code according to its advice manually.

---

cpplint --recursive --extensions=hpp,cpp,h,c ./

This one is better.

[Windrow14]

I have a problem.
Cpplint complains about Lines should be <= 80 characters long [whitespace/line_length] [2]. I can resolve it by cutting the line in the middle, but there seems no standard for where to cut the line and how many white space we should add at the front of the new line or where to align with.

For example:

### Line too long:
        if (SRT_INVALID_SOCK != srt_connect(srtsock, (const struct sockaddr *)&addr, sa_len)) {
### solution 1
        if (SRT_INVALID_SOCK != srt_connect(srtsock,
                                (const struct sockaddr *)&addr, sa_len)) {
### solution 2
        if (SRT_INVALID_SOCK != srt_connect(srtsock,
                                            (const struct sockaddr *)&addr, sa_len)) {
### solution 3
        if (SRT_INVALID_SOCK !=
            srt_connect(srtsock, (const struct sockaddr *)&addr, sa_len)) {

...

There are hundreds of solutions can make cpplint silent, but most of them looks even ugly than before...

[Windrow14]

I have a problem. Cpplint complains about Lines should be <= 80 characters long [whitespace/line_length] [2]. I can resolve it by cutting the line in the middle, but there seems no standard for where to cut the line and how many white space we should add at the front of the new line or where to align with.

For example:

### Line too long:
        if (SRT_INVALID_SOCK != srt_connect(srtsock, (const struct sockaddr *)&addr, sa_len)) {
### solution 1
        if (SRT_INVALID_SOCK != srt_connect(srtsock,
                                (const struct sockaddr *)&addr, sa_len)) {
### solution 2
        if (SRT_INVALID_SOCK != srt_connect(srtsock,
                                            (const struct sockaddr *)&addr, sa_len)) {
### solution 3
        if (SRT_INVALID_SOCK !=
            srt_connect(srtsock, (const struct sockaddr *)&addr, sa_len)) {

...

There are hundreds of solutions can make cpplint silent, but most of them looks even ugly than before...

There is a standard about function calling and arguments here: https://google.github.io/styleguide/cppguide.html#Function_Calls

[Windrow14]

I'd like to neglect some warnings from cpplint, such as: Do not use namespace using-directives. Use using-declarations instead. [build/namespaces] [5], <mutex> is an unapproved C++11 header. [build/c++11] [5], and some warnings related toSRT_DATA_MAP_INITIALIZER

[fujitatomoya]

However, cpplint is just a static code checker. It does not modify code automatically by itself. We need to modify code according to its advice manually.

I think that is developer's responsibility. Until workflow with cpplint green light, we will not merge the PR.

There are hundreds of solutions can make cpplint silent, but most of them looks even ugly than before...

if it does not work with cpplint, we can use // NOLINT with justification.

[fujitatomoya]

closing in favor of #22