/
no-array-index-key.js
197 lines (162 loc) · 4.83 KB
/
no-array-index-key.js
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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
/**
* @fileoverview Prevent usage of Array index in keys
* @author Joe Lencioni
*/
'use strict';
const has = require('has');
const astUtil = require('../util/ast');
const docsUrl = require('../util/docsUrl');
// ------------------------------------------------------------------------------
// Rule Definition
// ------------------------------------------------------------------------------
module.exports = {
meta: {
docs: {
description: 'Prevent usage of Array index in keys',
category: 'Best Practices',
recommended: false,
url: docsUrl('no-array-index-key')
},
schema: []
},
create: function(context) {
// --------------------------------------------------------------------------
// Public
// --------------------------------------------------------------------------
const indexParamNames = [];
const iteratorFunctionsToIndexParamPosition = {
every: 1,
filter: 1,
find: 1,
findIndex: 1,
forEach: 1,
map: 1,
reduce: 2,
reduceRight: 2,
some: 1
};
const ERROR_MESSAGE = 'Do not use Array index in keys';
function isArrayIndex(node) {
return node.type === 'Identifier'
&& indexParamNames.indexOf(node.name) !== -1;
}
function getMapIndexParamName(node) {
const callee = node.callee;
if (callee.type !== 'MemberExpression') {
return null;
}
if (callee.property.type !== 'Identifier') {
return null;
}
if (!has(iteratorFunctionsToIndexParamPosition, callee.property.name)) {
return null;
}
const firstArg = node.arguments[0];
if (!firstArg) {
return null;
}
if (!astUtil.isFunctionLikeExpression(firstArg)) {
return null;
}
const params = firstArg.params;
const indexParamPosition = iteratorFunctionsToIndexParamPosition[callee.property.name];
if (params.length < indexParamPosition + 1) {
return null;
}
return params[indexParamPosition].name;
}
function getIdentifiersFromBinaryExpression(side) {
if (side.type === 'Identifier') {
return side;
}
if (side.type === 'BinaryExpression') {
// recurse
const left = getIdentifiersFromBinaryExpression(side.left);
const right = getIdentifiersFromBinaryExpression(side.right);
return [].concat(left, right).filter(Boolean);
}
return null;
}
function checkPropValue(node) {
if (isArrayIndex(node)) {
// key={bar}
context.report({
node: node,
message: ERROR_MESSAGE
});
return;
}
if (node.type === 'TemplateLiteral') {
// key={`foo-${bar}`}
node.expressions.filter(isArrayIndex).forEach(() => {
context.report({node: node, message: ERROR_MESSAGE});
});
return;
}
if (node.type === 'BinaryExpression') {
// key={'foo' + bar}
const identifiers = getIdentifiersFromBinaryExpression(node);
identifiers.filter(isArrayIndex).forEach(() => {
context.report({node: node, message: ERROR_MESSAGE});
});
return;
}
}
return {
CallExpression: function(node) {
if (
node.callee
&& node.callee.type === 'MemberExpression'
&& ['createElement', 'cloneElement'].indexOf(node.callee.property.name) !== -1
&& node.arguments.length > 1
) {
// React.createElement
if (!indexParamNames.length) {
return;
}
const props = node.arguments[1];
if (props.type !== 'ObjectExpression') {
return;
}
props.properties.forEach(prop => {
if (!prop.key || prop.key.name !== 'key') {
// { ...foo }
// { foo: bar }
return;
}
checkPropValue(prop.value);
});
return;
}
const mapIndexParamName = getMapIndexParamName(node);
if (!mapIndexParamName) {
return;
}
indexParamNames.push(mapIndexParamName);
},
JSXAttribute: function(node) {
if (node.name.name !== 'key') {
// foo={bar}
return;
}
if (!indexParamNames.length) {
// Not inside a call expression that we think has an index param.
return;
}
const value = node.value;
if (!value || value.type !== 'JSXExpressionContainer') {
// key='foo' or just simply 'key'
return;
}
checkPropValue(value.expression);
},
'CallExpression:exit': function(node) {
const mapIndexParamName = getMapIndexParamName(node);
if (!mapIndexParamName) {
return;
}
indexParamNames.pop();
}
};
}
};