This document contains a list of guidelines for how code in this project should be formatted.

Overall code style

Some of our guidelines have automated checks. Run them using py CI.py --no_unit_tests.
If code is commented out, there should be an accompanying explanation of why the code was commented out and a suggestion of when it may be appropriate to uncomment it.
Use spaces, not tabs, for indentation and alignment. Indentation should be 4 spaces. Exceptions include YAML files, which use 2 spaces for indentation, and the Makefile, which uses tabs.
Unless requested by other guidelines (such as the next one), Don't use unnecessary parentheses, e.g. write a + b * c instead of a + (b * c).
Do not rely on operator precedence when nesting and/&& expressions inside or/|| expressions. Always use parentheses.
For hexadecimal numbers, use a lowercase x and uppercase letters as digits.

C code style

Include a space between a keyword like if or switch and the following parenthesis.
Use braces around single-line if, while, etc. bodies. The only time omitting braces is acceptable is when the body is a continue, break, or return statement written on the same line as the condition and not followed by else.
The opening brace of a function body, struct/union/enum body, or compound statement goes on the same line as the parameter list, condition, or do or else keyword.
The else keyword goes on the same line as the preceding closing brace.
Declare pointer variables with the asterisk aligned to the type (uint8_t* foo), not the variable name (uint8_t *foo).
Use spaces around binary operators, with the exception of . and ->.
When using type casting ((type) expression) or shift operators, prefer using explicit parentheses over relying on operator precedence.

Use ; for comments, not //.
All labels and directives are unindented, and all instructions are indented by 4 spaces.
The first parameter of an instruction starts at column 13.

Use f-strings instead of str.format or the % operator.
Prefer using parentheses for multiline expressions over using \ to continue a statement on the next line.
If a list is written with each element on a separate line, include a comma after the last element.
Use spaces around binary operators. (This does not include ., ,, :, etc.)
Use tuples rather than lists if both can be used interchangeably.