diff options
Diffstat (limited to 'vendor/github.com/BurntSushi/toml/type_fields.go')
-rw-r--r-- | vendor/github.com/BurntSushi/toml/type_fields.go | 242 |
1 files changed, 0 insertions, 242 deletions
diff --git a/vendor/github.com/BurntSushi/toml/type_fields.go b/vendor/github.com/BurntSushi/toml/type_fields.go deleted file mode 100644 index 608997c..0000000 --- a/vendor/github.com/BurntSushi/toml/type_fields.go +++ /dev/null @@ -1,242 +0,0 @@ -package toml - -// Struct field handling is adapted from code in encoding/json: -// -// Copyright 2010 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the Go distribution. - -import ( - "reflect" - "sort" - "sync" -) - -// A field represents a single field found in a struct. -type field struct { - name string // the name of the field (`toml` tag included) - tag bool // whether field has a `toml` tag - index []int // represents the depth of an anonymous field - typ reflect.Type // the type of the field -} - -// byName sorts field by name, breaking ties with depth, -// then breaking ties with "name came from toml tag", then -// breaking ties with index sequence. -type byName []field - -func (x byName) Len() int { return len(x) } - -func (x byName) Swap(i, j int) { x[i], x[j] = x[j], x[i] } - -func (x byName) Less(i, j int) bool { - if x[i].name != x[j].name { - return x[i].name < x[j].name - } - if len(x[i].index) != len(x[j].index) { - return len(x[i].index) < len(x[j].index) - } - if x[i].tag != x[j].tag { - return x[i].tag - } - return byIndex(x).Less(i, j) -} - -// byIndex sorts field by index sequence. -type byIndex []field - -func (x byIndex) Len() int { return len(x) } - -func (x byIndex) Swap(i, j int) { x[i], x[j] = x[j], x[i] } - -func (x byIndex) Less(i, j int) bool { - for k, xik := range x[i].index { - if k >= len(x[j].index) { - return false - } - if xik != x[j].index[k] { - return xik < x[j].index[k] - } - } - return len(x[i].index) < len(x[j].index) -} - -// typeFields returns a list of fields that TOML should recognize for the given -// type. The algorithm is breadth-first search over the set of structs to -// include - the top struct and then any reachable anonymous structs. -func typeFields(t reflect.Type) []field { - // Anonymous fields to explore at the current level and the next. - current := []field{} - next := []field{{typ: t}} - - // Count of queued names for current level and the next. - count := map[reflect.Type]int{} - nextCount := map[reflect.Type]int{} - - // Types already visited at an earlier level. - visited := map[reflect.Type]bool{} - - // Fields found. - var fields []field - - for len(next) > 0 { - current, next = next, current[:0] - count, nextCount = nextCount, map[reflect.Type]int{} - - for _, f := range current { - if visited[f.typ] { - continue - } - visited[f.typ] = true - - // Scan f.typ for fields to include. - for i := 0; i < f.typ.NumField(); i++ { - sf := f.typ.Field(i) - if sf.PkgPath != "" && !sf.Anonymous { // unexported - continue - } - opts := getOptions(sf.Tag) - if opts.skip { - continue - } - index := make([]int, len(f.index)+1) - copy(index, f.index) - index[len(f.index)] = i - - ft := sf.Type - if ft.Name() == "" && ft.Kind() == reflect.Ptr { - // Follow pointer. - ft = ft.Elem() - } - - // Record found field and index sequence. - if opts.name != "" || !sf.Anonymous || ft.Kind() != reflect.Struct { - tagged := opts.name != "" - name := opts.name - if name == "" { - name = sf.Name - } - fields = append(fields, field{name, tagged, index, ft}) - if count[f.typ] > 1 { - // If there were multiple instances, add a second, - // so that the annihilation code will see a duplicate. - // It only cares about the distinction between 1 or 2, - // so don't bother generating any more copies. - fields = append(fields, fields[len(fields)-1]) - } - continue - } - - // Record new anonymous struct to explore in next round. - nextCount[ft]++ - if nextCount[ft] == 1 { - f := field{name: ft.Name(), index: index, typ: ft} - next = append(next, f) - } - } - } - } - - sort.Sort(byName(fields)) - - // Delete all fields that are hidden by the Go rules for embedded fields, - // except that fields with TOML tags are promoted. - - // The fields are sorted in primary order of name, secondary order - // of field index length. Loop over names; for each name, delete - // hidden fields by choosing the one dominant field that survives. - out := fields[:0] - for advance, i := 0, 0; i < len(fields); i += advance { - // One iteration per name. - // Find the sequence of fields with the name of this first field. - fi := fields[i] - name := fi.name - for advance = 1; i+advance < len(fields); advance++ { - fj := fields[i+advance] - if fj.name != name { - break - } - } - if advance == 1 { // Only one field with this name - out = append(out, fi) - continue - } - dominant, ok := dominantField(fields[i : i+advance]) - if ok { - out = append(out, dominant) - } - } - - fields = out - sort.Sort(byIndex(fields)) - - return fields -} - -// dominantField looks through the fields, all of which are known to -// have the same name, to find the single field that dominates the -// others using Go's embedding rules, modified by the presence of -// TOML tags. If there are multiple top-level fields, the boolean -// will be false: This condition is an error in Go and we skip all -// the fields. -func dominantField(fields []field) (field, bool) { - // The fields are sorted in increasing index-length order. The winner - // must therefore be one with the shortest index length. Drop all - // longer entries, which is easy: just truncate the slice. - length := len(fields[0].index) - tagged := -1 // Index of first tagged field. - for i, f := range fields { - if len(f.index) > length { - fields = fields[:i] - break - } - if f.tag { - if tagged >= 0 { - // Multiple tagged fields at the same level: conflict. - // Return no field. - return field{}, false - } - tagged = i - } - } - if tagged >= 0 { - return fields[tagged], true - } - // All remaining fields have the same length. If there's more than one, - // we have a conflict (two fields named "X" at the same level) and we - // return no field. - if len(fields) > 1 { - return field{}, false - } - return fields[0], true -} - -var fieldCache struct { - sync.RWMutex - m map[reflect.Type][]field -} - -// cachedTypeFields is like typeFields but uses a cache to avoid repeated work. -func cachedTypeFields(t reflect.Type) []field { - fieldCache.RLock() - f := fieldCache.m[t] - fieldCache.RUnlock() - if f != nil { - return f - } - - // Compute fields without lock. - // Might duplicate effort but won't hold other computations back. - f = typeFields(t) - if f == nil { - f = []field{} - } - - fieldCache.Lock() - if fieldCache.m == nil { - fieldCache.m = map[reflect.Type][]field{} - } - fieldCache.m[t] = f - fieldCache.Unlock() - return f -} |