no-alert.js
4.83 KB
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
/**
* @fileoverview Rule to flag use of alert, confirm, prompt
* @author Nicholas C. Zakas
* @copyright 2015 Mathias Schreck
* @copyright 2013 Nicholas C. Zakas
*/
"use strict";
//------------------------------------------------------------------------------
// Helpers
//------------------------------------------------------------------------------
/**
* Checks if the given name is a prohibited identifier.
* @param {string} name The name to check
* @returns {boolean} Whether or not the name is prohibited.
*/
function isProhibitedIdentifier(name) {
return /^(alert|confirm|prompt)$/.test(name);
}
/**
* Reports the given node and identifier name.
* @param {RuleContext} context The ESLint rule context.
* @param {ASTNode} node The node to report on.
* @param {string} identifierName The name of the identifier.
* @returns {void}
*/
function report(context, node, identifierName) {
context.report(node, "Unexpected {{name}}.", { name: identifierName });
}
/**
* Returns the property name of a MemberExpression.
* @param {ASTNode} memberExpressionNode The MemberExpression node.
* @returns {string|undefined} Returns the property name if available, undefined else.
*/
function getPropertyName(memberExpressionNode) {
if (memberExpressionNode.computed) {
if (memberExpressionNode.property.type === "Literal") {
return memberExpressionNode.property.value;
}
} else {
return memberExpressionNode.property.name;
}
}
/**
* Finds the escope reference in the given scope.
* @param {Object} scope The scope to search.
* @param {ASTNode} node The identifier node.
* @returns {Reference|undefined} Returns the found reference or undefined if none were found.
*/
function findReference(scope, node) {
var references = scope.references.filter(function(reference) {
return reference.identifier.range[0] === node.range[0] &&
reference.identifier.range[1] === node.range[1];
});
if (references.length === 1) {
return references[0];
}
}
/**
* Checks if the given identifier name is shadowed in the given global scope.
* @param {Object} globalScope The global scope.
* @param {string} identifierName The identifier name to check
* @returns {boolean} Whether or not the name is shadowed globally.
*/
function isGloballyShadowed(globalScope, identifierName) {
var variable = globalScope.set.get(identifierName);
return Boolean(variable && variable.defs.length > 0);
}
/**
* Checks if the given identifier node is shadowed in the given scope.
* @param {Object} scope The current scope.
* @param {Object} globalScope The global scope.
* @param {string} node The identifier node to check
* @returns {boolean} Whether or not the name is shadowed.
*/
function isShadowed(scope, globalScope, node) {
var reference = findReference(scope, node),
identifierName = node.name;
if (reference) {
if (reference.resolved || isGloballyShadowed(globalScope, identifierName)) {
return true;
}
}
return false;
}
/**
* Checks if the given identifier node is a ThisExpression in the global scope or the global window property.
* @param {Object} scope The current scope.
* @param {Object} globalScope The global scope.
* @param {string} node The identifier node to check
* @returns {boolean} Whether or not the node is a reference to the global object.
*/
function isGlobalThisReferenceOrGlobalWindow(scope, globalScope, node) {
if (scope.type === "global" && node.type === "ThisExpression") {
return true;
} else if (node.name === "window") {
return !isShadowed(scope, globalScope, node);
}
return false;
}
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------
module.exports = function(context) {
var globalScope;
return {
"Program": function() {
globalScope = context.getScope();
},
"CallExpression": function(node) {
var callee = node.callee,
identifierName,
currentScope = context.getScope();
// without window.
if (callee.type === "Identifier") {
identifierName = callee.name;
if (!isShadowed(currentScope, globalScope, callee) && isProhibitedIdentifier(callee.name)) {
report(context, node, identifierName);
}
} else if (callee.type === "MemberExpression" && isGlobalThisReferenceOrGlobalWindow(currentScope, globalScope, callee.object)) {
identifierName = getPropertyName(callee);
if (isProhibitedIdentifier(identifierName)) {
report(context, node, identifierName);
}
}
}
};
};
module.exports.schema = [];