1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
package goquery
import (
"bytes"
"golang.org/x/net/html"
)
// used to determine if a set (map[*html.Node]bool) should be used
// instead of iterating over a slice. The set uses more memory and
// is slower than slice iteration for small N.
const minNodesForSet = 1000
var nodeNames = []string{
html.ErrorNode: "#error",
html.TextNode: "#text",
html.DocumentNode: "#document",
html.CommentNode: "#comment",
}
// NodeName returns the node name of the first element in the selection.
// It tries to behave in a similar way as the DOM's nodeName property
// (https://developer.mozilla.org/en-US/docs/Web/API/Node/nodeName).
//
// Go's net/html package defines the following node types, listed with
// the corresponding returned value from this function:
//
// ErrorNode : #error
// TextNode : #text
// DocumentNode : #document
// ElementNode : the element's tag name
// CommentNode : #comment
// DoctypeNode : the name of the document type
//
func NodeName(s *Selection) string {
if s.Length() == 0 {
return ""
}
return nodeName(s.Get(0))
}
// nodeName returns the node name of the given html node.
// See NodeName for additional details on behaviour.
func nodeName(node *html.Node) string {
if node == nil {
return ""
}
switch node.Type {
case html.ElementNode, html.DoctypeNode:
return node.Data
default:
if node.Type >= 0 && int(node.Type) < len(nodeNames) {
return nodeNames[node.Type]
}
return ""
}
}
// OuterHtml returns the outer HTML rendering of the first item in
// the selection - that is, the HTML including the first element's
// tag and attributes.
//
// Unlike InnerHtml, this is a function and not a method on the Selection,
// because this is not a jQuery method (in javascript-land, this is
// a property provided by the DOM).
func OuterHtml(s *Selection) (string, error) {
var buf bytes.Buffer
if s.Length() == 0 {
return "", nil
}
n := s.Get(0)
if err := html.Render(&buf, n); err != nil {
return "", err
}
return buf.String(), nil
}
// Loop through all container nodes to search for the target node.
func sliceContains(container []*html.Node, contained *html.Node) bool {
for _, n := range container {
if nodeContains(n, contained) {
return true
}
}
return false
}
// Checks if the contained node is within the container node.
func nodeContains(container *html.Node, contained *html.Node) bool {
// Check if the parent of the contained node is the container node, traversing
// upward until the top is reached, or the container is found.
for contained = contained.Parent; contained != nil; contained = contained.Parent {
if container == contained {
return true
}
}
return false
}
// Checks if the target node is in the slice of nodes.
func isInSlice(slice []*html.Node, node *html.Node) bool {
return indexInSlice(slice, node) > -1
}
// Returns the index of the target node in the slice, or -1.
func indexInSlice(slice []*html.Node, node *html.Node) int {
if node != nil {
for i, n := range slice {
if n == node {
return i
}
}
}
return -1
}
// Appends the new nodes to the target slice, making sure no duplicate is added.
// There is no check to the original state of the target slice, so it may still
// contain duplicates. The target slice is returned because append() may create
// a new underlying array. If targetSet is nil, a local set is created with the
// target if len(target) + len(nodes) is greater than minNodesForSet.
func appendWithoutDuplicates(target []*html.Node, nodes []*html.Node, targetSet map[*html.Node]bool) []*html.Node {
// if there are not that many nodes, don't use the map, faster to just use nested loops
// (unless a non-nil targetSet is passed, in which case the caller knows better).
if targetSet == nil && len(target)+len(nodes) < minNodesForSet {
for _, n := range nodes {
if !isInSlice(target, n) {
target = append(target, n)
}
}
return target
}
// if a targetSet is passed, then assume it is reliable, otherwise create one
// and initialize it with the current target contents.
if targetSet == nil {
targetSet = make(map[*html.Node]bool, len(target))
for _, n := range target {
targetSet[n] = true
}
}
for _, n := range nodes {
if !targetSet[n] {
target = append(target, n)
targetSet[n] = true
}
}
return target
}
// Loop through a selection, returning only those nodes that pass the predicate
// function.
func grep(sel *Selection, predicate func(i int, s *Selection) bool) (result []*html.Node) {
for i, n := range sel.Nodes {
if predicate(i, newSingleSelection(n, sel.document)) {
result = append(result, n)
}
}
return result
}
// Creates a new Selection object based on the specified nodes, and keeps the
// source Selection object on the stack (linked list).
func pushStack(fromSel *Selection, nodes []*html.Node) *Selection {
result := &Selection{nodes, fromSel.document, fromSel}
return result
}
|
