Common subsystem tasks

Common tasks for Subsystems

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Skipping individual targets

Many subsystems allow skipping specific targets. For example, you might have Python files that you want to not typecheck with mypy. In Pants, this is achieved with a skip_* field on the target. This is simple to implement.

1. Create a field for skipping your tool

from pants.engine.target import BoolField

class SkipFortranLintField(BoolField):
	alias = "skip_fortran_lint"
	default = False
	help = "If true, don't run fortran-lint on this target's code."

2. Register this field on the appropriate targets.

def rules():
	return [
		FortranSourceTarget.register_plugin_field(SkipFortranLintField),
	]

3. Add this field as part of your subsystems opt_out method:

from dataclasses import dataclass

from pants.engine.target import FieldSet, Target


@dataclass
class FortranLintFieldSet(FieldSet):
    required_fields = (FortranSourceField,)

    source: FortranSourceField

    @classmethod
    def opt_out(cls, tgt: Target) -> bool:
        return tgt.get(SkipFortranLintField).value