Over the years, SwiftLintFramework had become a fairly massive monolith,
containing over 400 source files with both core infrastructure and
rules.
Architecturally, the rules should rely on the core infrastructure but
not the other way around. There are two exceptions to this:
`custom_rules` and `superfluous_disable_command` which need special
integration with the linter infrastructure.
Now the time has come to formalize this architecture and one way to do
that is to move the core SwiftLint functionality out of
SwiftLintFramework and into a new SwiftLintCore module that the rules
can depend on.
Beyond enforcing architectural patterns, this also has the advantage of
speeding up incremental compilation by skipping rebuilding the core
functionality when iterating on rules.
Because the core functionality is always useful when building rules, I'm
opting to import SwiftLintCore in SwiftLintFramework as `@_exported` so
that it's implicitly available to all files in SwiftLintFramework
without needing to import it directly.
In a follow-up I'll also split the built-in rules and the extra rules
into their own modules. More modularization is possible from there, but
not planned.
The bulk of this PR just moves files from `Source/SwiftLintFramework/*`
to `Source/SwiftLintCore/*`. There are some other changes that can't be
split up into their own PRs:
* Change jazzy to document the SwiftLintCore module instead of
SwiftLintFramework.
* Change imports in unit tests to reflect where code was moved to.
* Update `sourcery` make rule to reflect where code was moved to.
* Create a new `coreRules` array and register those rules with the
registry. This allows the `custom_rules` and
`superfluous_disable_command` rule implementations to remain internal
to the SwiftLintCore module, preventing more implementation details
from leaking across architectural layers.
* Move `RuleRegistry.registerAllRulesOnce()` out of the type declaration
and up one level so it can access rules defined downstream from
SwiftLintCore.
Current events have renewed the conversation in our community about the roles of terminology with racist connotations in our software. Many companies and developers are now taking appropriate steps to remove this terminology from their codebases and products. (e.g. [GitHub](https://twitter.com/natfriedman/status/1271253144442253312)) This small rule prevents the use of declarations that contain any of the terms: whitelist, blacklist, master, and slave. It may be appropriate to add more terms to this list now or in the future.
This PR adds a new `unused_declaration` analyzer rule to lint for unused declarations.
By default, detects unused `fileprivate`, `private` and `internal` declarations.
Configure the rule with `include_public_and_open: true` to also detect unused `public` and `open` declarations.
Completely remove the `unused_private_declaration` rule.
This is built on the work enabling collecting rule infrastructure in https://github.com/realm/SwiftLint/pull/2714.
JP Simard
Danny Mösch
Frederick Pietschmann
Dalton Claybrook
Keith Smiley