Add 'make format' for format Python code

[hzeller]

The CI catches these, but would be good if we can have that beforehand.

[hzeller]

When running 'make format', this complains. Is this because of actual formatting complaints or because my laptop has Python 2.7 installed?

$ make format
flake8 generators/fx68k generators/ibex generators/path_generator generators/swerv generators/template_generator generators/yosys_hana tools/BaseRunner.py tools/check-runners tools/runner tools/sv-report tools/BaseRunner.py tools/runners/Slang.py tools/runners/Yosys.py tools/runners/tree_sitter_verilog.py tools/runners/Icarus.py tools/runners/Verilator.py tools/runners/Odin.py tools/runners/Sv2v_zachjs.py
generators/path_generator:49:1: E999 SyntaxError: only named arguments may follow *expression
tools/runner:113:9: F821 undefined name 'PermissionError'
tools/runner:113:26: F821 undefined name 'FileExistsError'
tools/runners/tree_sitter_verilog.py:28:1: E999 SyntaxError: only named arguments may follow *expression

[mithro]

This is what prjxray does for make format.

See https://github.com/SymbiFlow/prjxray/blob/daa516585eb31fe7f05cdb8d4f080d4cb96751d1/Makefile#L54-L77

# Auto formatting of code.
# ------------------------
FORMAT_EXCLUDE = $(foreach x,$(ALL_EXCLUDE),-and -not -path './$(x)/*')

CLANG_FORMAT ?= clang-format-5.0
format-cpp:
    find . -name \*.cc $(FORMAT_EXCLUDE) -print0 | xargs -0 -P $$(nproc) ${CLANG_FORMAT} -style=file -i
    find . -name \*.h $(FORMAT_EXCLUDE) -print0 | xargs -0 -P $$(nproc) ${CLANG_FORMAT} -style=file -i

format-docs:
    ./.github/update-contributing.py

PYTHON_FORMAT ?= yapf
format-py:
    $(IN_ENV) find . -name \*.py $(FORMAT_EXCLUDE) -print0 | xargs -0 -P $$(nproc) yapf -p -i

TCL_FORMAT ?= utils//tcl-reformat.sh
format-tcl:
    find . -name \*.tcl $(FORMAT_EXCLUDE) -print0 | xargs -0 -P $$(nproc) -n 1 $(TCL_FORMAT)

format: format-cpp format-docs format-py format-tcl
    @true

.PHONY: format format-cpp format-py format-tcl

GitHub

SymbiFlow/prjxray

Documenting the Xilinx 7-series bit-stream format. - SymbiFlow/prjxray

[tgorochowik]

@hzeller it seems that your flake8 instance is installed for python2, not python3, we will have to check if we can be smarter about this and require it to be installed for py3 (I guess we should be able to invoke it differently)