tree fcfe22c820ee38cfa567051456fa5a11473bcb5d
parent 60fea57cb8fb434fe6d37981fcb5a7f66ad596d0
author Alexander Hansen <alexander.hansen@9elements.com> 1695924311 +0200
committer Patrick Williams <patrick@stwcx.xyz> 1698848007 +0000

clang-tidy: propose a base .clang-tidy

When there is a specific recommendation, it is taken from Cpp Core
guidelines [1] or clang-tidy defaults.

- readability-function-size.LineThreshold
  was chosen to support
  [ F.3 Keep functions short and simple ]

  They recommend 60 lines to flag functions which would not fit on a
  screen.

- readability-function-size.ParameterThreshold
  was chosen to support
  [ F.2: A function should perform a single logical operation ]

  They recommend to be suspicious of functions with 7 or more
  parameters.

- readability-function-cognitive-complexity.Threshold
  was chosen to support
  [ F.3: Keep functions short and simple ]

  They recommend a cyclomatic complexity of 10 or less.
  However, cyclomatic complexity is not implemented in clang-tidy,
  therefore going with the clang-tidy default.

What is the goal of this change?

- making it easier for people to read the code.

- making it easier to perform refactorings without breaking stuff

- making it easier to review changes

Who will be responsible for making the required changes?

- Everyone who is interested. The plan is to atleast get some of the
  most important pieces into a more readable state. Examples are
  dbus-sensors, entity-manager, x86-power-control.

- The plan is to enable some of these checks as errors once a repo
  comes into compliance. After that, contributors will be responsible
  to ensure their changes meet these checks.

Tradeoffs:

- There might be more code overall, as functions will be smaller.
- People might be required to do another (refactoring) iteration on
  their changes if some of these checks become hard errors.
- Refactoring code to meet these checks might introduce bugs.

[1] https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines

Change-Id: Icbdd55d2f672037a57d8ed08d52b20427e9e1e4f
Signed-off-by: Alexander Hansen <alexander.hansen@9elements.com>