diff options
Diffstat (limited to 'src/log/slog/value.go')
| -rw-r--r-- | src/log/slog/value.go | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/src/log/slog/value.go b/src/log/slog/value.go index 71a59d2639..224848f695 100644 --- a/src/log/slog/value.go +++ b/src/log/slog/value.go @@ -164,9 +164,32 @@ func DurationValue(v time.Duration) Value { // GroupValue returns a new Value for a list of Attrs. // The caller must not subsequently mutate the argument slice. func GroupValue(as ...Attr) Value { + // Remove empty groups. + // It is simpler overall to do this at construction than + // to check each Group recursively for emptiness. + if n := countEmptyGroups(as); n > 0 { + as2 := make([]Attr, 0, len(as)-n) + for _, a := range as { + if !a.Value.isEmptyGroup() { + as2 = append(as2, a) + } + } + as = as2 + } return Value{num: uint64(len(as)), any: groupptr(unsafe.SliceData(as))} } +// countEmptyGroups returns the number of empty group values in its argument. +func countEmptyGroups(as []Attr) int { + n := 0 + for _, a := range as { + if a.Value.isEmptyGroup() { + n++ + } + } + return n +} + // AnyValue returns a Value for the supplied value. // // If the supplied value is of type Value, it is returned @@ -399,6 +422,17 @@ func (v Value) Equal(w Value) bool { } } +// isEmptyGroup reports whether v is a group that has no attributes. +func (v Value) isEmptyGroup() bool { + if v.Kind() != KindGroup { + return false + } + // We do not need to recursively examine the group's Attrs for emptiness, + // because GroupValue removed them when the group was constructed, and + // groups are immutable. + return len(v.group()) == 0 +} + // append appends a text representation of v to dst. // v is formatted as with fmt.Sprint. func (v Value) append(dst []byte) []byte { |