best_coding_practice.md

Best Coding Practice

1. Always compile all, test all and lint all.

   apollo.sh check

2. Always write unit test and put it along with the source code.

   foobar.h
   foobar.cc
   foobar_test.cc
   

3. A bazel target contains at most one header and one source file.

   cc_library(
     name = "foobar",
     hdrs = ["foobar.h"],
     srcs = ["foobar.cc"],
     deps = [
       ...
     ],
   )
   
   cc_test(
     name = "foobar_test",
     srcs = ["foobar_test.cc"],
     deps = [
       ":foobar",
       ...
     ]
   )
   

4. Simple and unified function signature.

   void foobar(const InputType& input1, const int input2, ...,
               OutputType* output1, ...);
   
   // RVO machanism will help you avoid unnecessary object copy.
   // See https://en.wikipedia.org/wiki/Copy_elision#Return_value_optimization
   OutputType foobar(const InputType& input);

5. Use const whenever possible.

   // Variables that don't change.
   const int current_size = vec.size();
   // Functions that have no side effect.
   const std::string& name() const;