matterbridge/vendor/github.com/wiggin77/merror/merror.go

121 lines
2.5 KiB
Go

package merror
import "sync"
// MError represents zero or more errors that can be
// accumulated via the `Append` method.
type MError struct {
cap int
mux sync.RWMutex
errors []error
overflow int
formatter FormatterFunc
}
// New returns a new instance of `MError` with no limit on the
// number of errors that can be appended.
func New() *MError {
me := &MError{}
me.errors = make([]error, 0, 10)
return me
}
// NewWithCap returns a new instance of `MError` with a maximum
// capacity of `cap` errors. If exceeded only the overflow counter
// will be incremented.
//
// A `cap` of zero of less means no cap and max size of a slice
// on the current platform is the upper bound.
func NewWithCap(cap int) *MError {
me := New()
me.cap = cap
return me
}
// Append adds an error to the aggregated error list.
func (me *MError) Append(err error) {
if err == nil {
return
}
me.mux.Lock()
defer me.mux.Unlock()
if me.cap > 0 && len(me.errors) >= me.cap {
me.overflow++
} else {
me.errors = append(me.errors, err)
}
}
// Errors returns a slice of the `error` instances that have been
// appended to this `MError`.
func (me *MError) Errors() []error {
me.mux.RLock()
defer me.mux.RUnlock()
errs := make([]error, len(me.errors))
copy(errs, me.errors)
return errs
}
// Len returns the number of errors that have been appended.
func (me *MError) Len() int {
me.mux.RLock()
defer me.mux.RUnlock()
return len(me.errors)
}
// Overflow returns the number of errors that have been truncated
// because maximum capacity was exceeded.
func (me *MError) Overflow() int {
me.mux.RLock()
defer me.mux.RUnlock()
return me.overflow
}
// SetFormatter sets the `FormatterFunc` to be used when `Error` is
// called. The previous `FormatterFunc` is returned.
func (me *MError) SetFormatter(f FormatterFunc) (old FormatterFunc) {
me.mux.Lock()
defer me.mux.Unlock()
old = me.formatter
me.formatter = f
return
}
// ErrorOrNil returns nil if this `MError` contains no errors,
// otherwise this `MError` is returned.
func (me *MError) ErrorOrNil() error {
if me == nil {
return nil
}
me.mux.RLock()
defer me.mux.RUnlock()
if len(me.errors) == 0 {
return nil
}
return me
}
// Error returns a string representation of this MError.
// The output format depends on the `Formatter` set for this
// merror instance, or the global formatter if none set.
func (me *MError) Error() string {
me.mux.RLock()
defer me.mux.RUnlock()
f := me.formatter
if f == nil {
f = GlobalFormatter
}
return f(me)
}