func()

in apidiff/correspondence.go [28:132]

• 90 lines of code
• 43 McCabe index (conditional complexity)

func (d *differ) corr(old, new types.Type, p *ifacePair) bool {
	// Structure copied from types.Identical.
	switch old := old.(type) {
	case *types.Basic:
		return types.Identical(old, new)

	case *types.Array:
		if new, ok := new.(*types.Array); ok {
			return d.corr(old.Elem(), new.Elem(), p) && old.Len() == new.Len()
		}

	case *types.Slice:
		if new, ok := new.(*types.Slice); ok {
			return d.corr(old.Elem(), new.Elem(), p)
		}

	case *types.Map:
		if new, ok := new.(*types.Map); ok {
			return d.corr(old.Key(), new.Key(), p) && d.corr(old.Elem(), new.Elem(), p)
		}

	case *types.Chan:
		if new, ok := new.(*types.Chan); ok {
			return d.corr(old.Elem(), new.Elem(), p) && old.Dir() == new.Dir()
		}

	case *types.Pointer:
		if new, ok := new.(*types.Pointer); ok {
			return d.corr(old.Elem(), new.Elem(), p)
		}

	case *types.Signature:
		if new, ok := new.(*types.Signature); ok {
			pe := d.corr(old.Params(), new.Params(), p)
			re := d.corr(old.Results(), new.Results(), p)
			return old.Variadic() == new.Variadic() && pe && re
		}

	case *types.Tuple:
		if new, ok := new.(*types.Tuple); ok {
			for i := 0; i < old.Len(); i++ {
				if i >= new.Len() || !d.corr(old.At(i).Type(), new.At(i).Type(), p) {
					return false
				}
			}
			return old.Len() == new.Len()
		}

	case *types.Struct:
		if new, ok := new.(*types.Struct); ok {
			for i := 0; i < old.NumFields(); i++ {
				if i >= new.NumFields() {
					return false
				}
				of := old.Field(i)
				nf := new.Field(i)
				if of.Anonymous() != nf.Anonymous() ||
					old.Tag(i) != new.Tag(i) ||
					!d.corr(of.Type(), nf.Type(), p) ||
					!d.corrFieldNames(of, nf) {
					return false
				}
			}
			return old.NumFields() == new.NumFields()
		}

	case *types.Interface:
		if new, ok := new.(*types.Interface); ok {
			// Deal with circularity. See the comment in types.Identical.
			q := &ifacePair{old, new, p}
			for p != nil {
				if p.identical(q) {
					return true // same pair was compared before
				}
				p = p.prev
			}
			oldms := d.sortedMethods(old)
			newms := d.sortedMethods(new)
			for i, om := range oldms {
				if i >= len(newms) {
					return false
				}
				nm := newms[i]
				if d.methodID(om) != d.methodID(nm) || !d.corr(om.Type(), nm.Type(), q) {
					return false
				}
			}
			return old.NumMethods() == new.NumMethods()
		}

	case *types.Named:
		if new, ok := new.(*types.Named); ok {
			return d.establishCorrespondence(old, new)
		}
		if new, ok := new.(*types.Basic); ok {
			// Basic types are defined types, too, so we have to support them.

			return d.establishCorrespondence(old, new)
		}

	default:
		panic("unknown type kind")
	}
	return false
}