Rule

A Scalafix Rule.

To provide automatic fixes for this rule, override the fix method. Example:

object ReverseNames extends Rule("ReverseNames") {
  override def fix(ctx: RuleCtx) =
    ctx.tree.collect {
      case name @ Name(value) => ctx.replaceTree(name, value.reverse)
    }.asPatch
}

To report violations of this rule (without automatic fix), override the check method. Example:

// example syntactic linter
object NoNulls extends Rule("NoNulls") {
  val error = LintCategory.error("Nulls are not allowed.")
  override def check(ctx: RuleCtx): List[Diagnostic] = ctx.tree.collect {
    case nil @ q"null" => error.at(nil.pos)
  }
}

Self Type: Rule

Linear Supertypes

AnyRef, Any

Known Subclasses

SemanticRule

Instance Constructors

new Rule(ruleName: v0.RuleName)

ruleName
Name of this rule that users call via .scalafix.conf or in the sbt shell. By convention, a name should be PascalCase matching the class name of the rule. Example good name: NoVars, ExplicitUnit. Example bad name: no-vars, noVars, FixVars.

Value Members

final def !=(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def ##(): Int

Definition Classes
AnyRef → Any
def +(other: String): String

Implicit information
This member is added by an implicit conversion from Rule to any2stringadd[Rule] performed by method any2stringadd in scala.Predef.
Definition Classes
any2stringadd
def ->[B](y: B): (Rule, B)

Implicit information
This member is added by an implicit conversion from Rule to ArrowAssoc[Rule] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc
Annotations
@inline()
final def ==(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def apply(ctx: RuleCtx, patches: Map[v0.RuleName, v0.Patch]): String
final def apply(ctx: RuleCtx, patch: v0.Patch): String
final def apply(input: String): String
final def apply(input: scala.meta.Input, config: ScalafixConfig = ScalafixConfig.default): String
final def apply(ctx: RuleCtx): String

Returns string output of applying this single patch.
final def applyAndLint(ctx: RuleCtx): (String, List[RuleDiagnostic])
final def asInstanceOf[T0]: T0

Definition Classes
Any
def check(ctx: RuleCtx): Seq[v0.Diagnostic]

Returns linter messages to report violations of this rule.
def clone(): AnyRef

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( ... )
def description: String

A single sentence summary of what this rule does.
final def diff(ctx: RuleCtx, patch: v0.Patch): String

Attributes
protected
final def diff(ctx: RuleCtx): String

Returns unified diff from applying this patch
def ensuring(cond: (Rule) ⇒ Boolean, msg: ⇒ Any): Rule

Implicit information
This member is added by an implicit conversion from Rule to Ensuring[Rule] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
def ensuring(cond: (Rule) ⇒ Boolean): Rule

Implicit information
This member is added by an implicit conversion from Rule to Ensuring[Rule] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
def ensuring(cond: Boolean, msg: ⇒ Any): Rule

Implicit information
This member is added by an implicit conversion from Rule to Ensuring[Rule] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
def ensuring(cond: Boolean): Rule

Implicit information
This member is added by an implicit conversion from Rule to Ensuring[Rule] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
final def eq(arg0: AnyRef): Boolean

Definition Classes
AnyRef
def equals(arg0: Any): Boolean

Definition Classes
AnyRef → Any
def finalize(): Unit

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( classOf[java.lang.Throwable] )
def fix(ctx: RuleCtx): v0.Patch

Returns a patch to fix violations of this rule.
def fixWithName(ctx: RuleCtx): Map[v0.RuleName, v0.Patch]

Attributes
protected[scalafix]
def formatted(fmtstr: String): String

Implicit information
This member is added by an implicit conversion from Rule to StringFormat[Rule] performed by method StringFormat in scala.Predef.
Definition Classes
StringFormat
Annotations
@inline()
final def getClass(): Class[_]

Definition Classes
AnyRef → Any
def hashCode(): Int

Definition Classes
AnyRef → Any
def init(config: Conf): Configured[Rule]

Initialize this rule with the given user configuration.
Initialize this rule with the given user configuration.
This method is called once by scalafix before rule is called. Use this method to either read custom configuration or to build expensive indices.
config
The .scalafix.conf configuration.
returns
the initialized rule or an error. If no initialization is needed, return Configured.Ok(this).
final def isInstanceOf[T0]: Boolean

Definition Classes
Any
final def merge(other: Rule): Rule

Combine this rule with another rule.
final def name: v0.RuleName
final def ne(arg0: AnyRef): Boolean

Definition Classes
AnyRef
final def notify(): Unit

Definition Classes
AnyRef
final def notifyAll(): Unit

Definition Classes
AnyRef
def semanticOption: Option[SemanticdbIndex]

Attributes
protected[scalafix]
final def synchronized[T0](arg0: ⇒ T0): T0

Definition Classes
AnyRef
final def toString(): String

Definition Classes
Rule → AnyRef → Any
final def wait(): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long, arg1: Int): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
def →[B](y: B): (Rule, B)

Implicit information
This member is added by an implicit conversion from Rule to ArrowAssoc[Rule] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc

Related Docs: object Rule | package v0

abstract class Rule extends AnyRef

Instance Constructors

new Rule(ruleName: v0.RuleName)

Value Members

final def !=(arg0: Any): Boolean

final def ##(): Int

def +(other: String): String

def ->[B](y: B): (Rule, B)

final def ==(arg0: Any): Boolean

final def apply(ctx: RuleCtx, patches: Map[v0.RuleName, v0.Patch]): String

final def apply(ctx: RuleCtx, patch: v0.Patch): String

final def apply(input: String): String

final def apply(input: scala.meta.Input, config: ScalafixConfig = ScalafixConfig.default): String

final def apply(ctx: RuleCtx): String

final def applyAndLint(ctx: RuleCtx): (String, List[RuleDiagnostic])

final def asInstanceOf[T0]: T0

def check(ctx: RuleCtx): Seq[v0.Diagnostic]

def clone(): AnyRef

def description: String

final def diff(ctx: RuleCtx, patch: v0.Patch): String

final def diff(ctx: RuleCtx): String

def ensuring(cond: (Rule) ⇒ Boolean, msg: ⇒ Any): Rule

def ensuring(cond: (Rule) ⇒ Boolean): Rule

def ensuring(cond: Boolean, msg: ⇒ Any): Rule

def ensuring(cond: Boolean): Rule

final def eq(arg0: AnyRef): Boolean

def equals(arg0: Any): Boolean

def finalize(): Unit

def fix(ctx: RuleCtx): v0.Patch

def fixWithName(ctx: RuleCtx): Map[v0.RuleName, v0.Patch]

def formatted(fmtstr: String): String

final def getClass(): Class[_]

def hashCode(): Int

def init(config: Conf): Configured[Rule]

final def isInstanceOf[T0]: Boolean

final def merge(other: Rule): Rule

final def name: v0.RuleName

final def ne(arg0: AnyRef): Boolean

final def notify(): Unit

final def notifyAll(): Unit

def semanticOption: Option[SemanticdbIndex]

final def synchronized[T0](arg0: ⇒ T0): T0

final def toString(): String

final def wait(): Unit

final def wait(arg0: Long, arg1: Int): Unit

final def wait(arg0: Long): Unit

def →[B](y: B): (Rule, B)

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd from Rule to any2stringadd[Rule]

Inherited by implicit conversion StringFormat from Rule to StringFormat[Rule]

Inherited by implicit conversion Ensuring from Rule to Ensuring[Rule]

Inherited by implicit conversion ArrowAssoc from Rule to ArrowAssoc[Rule]

Ungrouped