From 56e74239d6b34df8f30ef046f0b0ff4ff0866a71 Mon Sep 17 00:00:00 2001 From: =Corey Hulen Date: Sun, 14 Jun 2015 23:53:32 -0800 Subject: first commit --- .../src/github.com/stretchr/objx/accessors.go | 179 +++++++++++++++++++++ 1 file changed, 179 insertions(+) create mode 100644 Godeps/_workspace/src/github.com/stretchr/objx/accessors.go (limited to 'Godeps/_workspace/src/github.com/stretchr/objx/accessors.go') diff --git a/Godeps/_workspace/src/github.com/stretchr/objx/accessors.go b/Godeps/_workspace/src/github.com/stretchr/objx/accessors.go new file mode 100644 index 000000000..721bcac79 --- /dev/null +++ b/Godeps/_workspace/src/github.com/stretchr/objx/accessors.go @@ -0,0 +1,179 @@ +package objx + +import ( + "fmt" + "regexp" + "strconv" + "strings" +) + +// arrayAccesRegexString is the regex used to extract the array number +// from the access path +const arrayAccesRegexString = `^(.+)\[([0-9]+)\]$` + +// arrayAccesRegex is the compiled arrayAccesRegexString +var arrayAccesRegex = regexp.MustCompile(arrayAccesRegexString) + +// Get gets the value using the specified selector and +// returns it inside a new Obj object. +// +// If it cannot find the value, Get will return a nil +// value inside an instance of Obj. +// +// Get can only operate directly on map[string]interface{} and []interface. +// +// Example +// +// To access the title of the third chapter of the second book, do: +// +// o.Get("books[1].chapters[2].title") +func (m Map) Get(selector string) *Value { + rawObj := access(m, selector, nil, false, false) + return &Value{data: rawObj} +} + +// Set sets the value using the specified selector and +// returns the object on which Set was called. +// +// Set can only operate directly on map[string]interface{} and []interface +// +// Example +// +// To set the title of the third chapter of the second book, do: +// +// o.Set("books[1].chapters[2].title","Time to Go") +func (m Map) Set(selector string, value interface{}) Map { + access(m, selector, value, true, false) + return m +} + +// access accesses the object using the selector and performs the +// appropriate action. +func access(current, selector, value interface{}, isSet, panics bool) interface{} { + + switch selector.(type) { + case int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64: + + if array, ok := current.([]interface{}); ok { + index := intFromInterface(selector) + + if index >= len(array) { + if panics { + panic(fmt.Sprintf("objx: Index %d is out of range. Slice only contains %d items.", index, len(array))) + } + return nil + } + + return array[index] + } + + return nil + + case string: + + selStr := selector.(string) + selSegs := strings.SplitN(selStr, PathSeparator, 2) + thisSel := selSegs[0] + index := -1 + var err error + + // https://github.com/stretchr/objx/issues/12 + if strings.Contains(thisSel, "[") { + + arrayMatches := arrayAccesRegex.FindStringSubmatch(thisSel) + + if len(arrayMatches) > 0 { + + // Get the key into the map + thisSel = arrayMatches[1] + + // Get the index into the array at the key + index, err = strconv.Atoi(arrayMatches[2]) + + if err != nil { + // This should never happen. If it does, something has gone + // seriously wrong. Panic. + panic("objx: Array index is not an integer. Must use array[int].") + } + + } + } + + if curMap, ok := current.(Map); ok { + current = map[string]interface{}(curMap) + } + + // get the object in question + switch current.(type) { + case map[string]interface{}: + curMSI := current.(map[string]interface{}) + if len(selSegs) <= 1 && isSet { + curMSI[thisSel] = value + return nil + } else { + current = curMSI[thisSel] + } + default: + current = nil + } + + if current == nil && panics { + panic(fmt.Sprintf("objx: '%v' invalid on object.", selector)) + } + + // do we need to access the item of an array? + if index > -1 { + if array, ok := current.([]interface{}); ok { + if index < len(array) { + current = array[index] + } else { + if panics { + panic(fmt.Sprintf("objx: Index %d is out of range. Slice only contains %d items.", index, len(array))) + } + current = nil + } + } + } + + if len(selSegs) > 1 { + current = access(current, selSegs[1], value, isSet, panics) + } + + } + + return current + +} + +// intFromInterface converts an interface object to the largest +// representation of an unsigned integer using a type switch and +// assertions +func intFromInterface(selector interface{}) int { + var value int + switch selector.(type) { + case int: + value = selector.(int) + case int8: + value = int(selector.(int8)) + case int16: + value = int(selector.(int16)) + case int32: + value = int(selector.(int32)) + case int64: + value = int(selector.(int64)) + case uint: + value = int(selector.(uint)) + case uint8: + value = int(selector.(uint8)) + case uint16: + value = int(selector.(uint16)) + case uint32: + value = int(selector.(uint32)) + case uint64: + value = int(selector.(uint64)) + default: + panic("objx: array access argument is not an integer type (this should never happen)") + } + + return value +} -- cgit v1.2.3-1-g7c22