83 lines
1.8 KiB
Go

package gocyclo
import (
"fmt"
"go/token"
"go/ast"
)
type Stat struct {
PkgName string
FuncName string
Complexity int
Pos token.Position
}
func (s Stat) String() string {
return fmt.Sprintf("%d %s %s %s", s.Complexity, s.PkgName, s.FuncName, s.Pos)
}
func BuildStats(f *ast.File, fset *token.FileSet, stats []Stat) []Stat {
for _, decl := range f.Decls {
if fn, ok := decl.(*ast.FuncDecl); ok {
stats = append(stats, Stat{
PkgName: f.Name.Name,
FuncName: funcName(fn),
Complexity: complexity(fn),
Pos: fset.Position(fn.Pos()),
})
}
}
return stats
}
// funcName returns the name representation of a function or method:
// "(Type).Name" for methods or simply "Name" for functions.
func funcName(fn *ast.FuncDecl) string {
if fn.Recv != nil {
if fn.Recv.NumFields() > 0 {
typ := fn.Recv.List[0].Type
return fmt.Sprintf("(%s).%s", recvString(typ), fn.Name)
}
}
return fn.Name.Name
}
// recvString returns a string representation of recv of the
// form "T", "*T", or "BADRECV" (if not a proper receiver type).
func recvString(recv ast.Expr) string {
switch t := recv.(type) {
case *ast.Ident:
return t.Name
case *ast.StarExpr:
return "*" + recvString(t.X)
}
return "BADRECV"
}
// complexity calculates the cyclomatic complexity of a function.
func complexity(fn *ast.FuncDecl) int {
v := complexityVisitor{}
ast.Walk(&v, fn)
return v.Complexity
}
type complexityVisitor struct {
// Complexity is the cyclomatic complexity
Complexity int
}
// Visit implements the ast.Visitor interface.
func (v *complexityVisitor) Visit(n ast.Node) ast.Visitor {
switch n := n.(type) {
case *ast.FuncDecl, *ast.IfStmt, *ast.ForStmt, *ast.RangeStmt, *ast.CaseClause, *ast.CommClause:
v.Complexity++
case *ast.BinaryExpr:
if n.Op == token.LAND || n.Op == token.LOR {
v.Complexity++
}
}
return v
}