fillswitch

Documentation

Overview

Package fillswitch identifies switches with missing cases.

It reports a diagnostic for each type switch or 'enum' switch that has missing cases, and suggests a fix to fill them in.

The possible cases are: for a type switch, each accessible named type T or pointer *T that is assignable to the interface type; and for an 'enum' switch, each accessible named constant of the same type as the switch value.

For an 'enum' switch, it will suggest cases for all possible values of the type.

type Suit int8
const (
	 Spades Suit = iota
	 Hearts
	 Diamonds
	 Clubs
)

var s Suit
switch s {
case Spades:
}

It will report a diagnostic with a suggested fix to fill in the remaining cases:

var s Suit
switch s {
case Spades:
case Hearts:
case Diamonds:
case Clubs:
default:
	 panic(fmt.Sprintf("unexpected Suit: %v", s))
}

For a type switch, it will suggest cases for all types that implement the interface.

var stmt ast.Stmt
switch stmt.(type) {
case *ast.IfStmt:
}

It will report a diagnostic with a suggested fix to fill in the remaining cases:

var stmt ast.Stmt
switch stmt.(type) {
case *ast.IfStmt:
case *ast.ForStmt:
case *ast.RangeStmt:
case *ast.AssignStmt:
case *ast.GoStmt:
...
default:
	 panic(fmt.Sprintf("unexpected ast.Stmt: %T", stmt))
}

Index

• func Diagnose(f *ast.File, start, end token.Pos, pkg *types.Package, info *types.Info) []analysis.Diagnostic

Functions

func Diagnose

func Diagnose(f *ast.File, start, end token.Pos, pkg *types.Package, info *types.Info) []analysis.Diagnostic

Diagnose computes diagnostics for switch statements with missing cases overlapping with the provided start and end position of file f.

If either start or end is invalid, the entire file is inspected.