no-undef.js
3.36 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
/**
* @fileoverview Rule to flag references to undeclared variables.
* @author Mark Macdonald
* @copyright 2015 Nicholas C. Zakas. All rights reserved.
* @copyright 2013 Mark Macdonald. All rights reserved.
*/
"use strict";
//------------------------------------------------------------------------------
// Requirements
//------------------------------------------------------------------------------
var astUtils = require("../ast-utils");
//------------------------------------------------------------------------------
// Helpers
//------------------------------------------------------------------------------
var hasOwnProperty = Object.prototype.hasOwnProperty;
/**
* Check if a variable is an implicit declaration
* @param {ASTNode} variable node to evaluate
* @returns {boolean} True if its an implicit declaration
* @private
*/
function isImplicitGlobal(variable) {
return variable.defs.every(function(def) {
return def.type === "ImplicitGlobalVariable";
});
}
/**
* Gets the declared variable, defined in `scope`, that `ref` refers to.
* @param {Scope} scope The scope in which to search.
* @param {Reference} ref The reference to find in the scope.
* @returns {Variable} The variable, or null if ref refers to an undeclared variable.
*/
function getDeclaredGlobalVariable(scope, ref) {
var variable = astUtils.getVariableByName(scope, ref.identifier.name);
// If it's an implicit global, it must have a `writeable` field (indicating it was declared)
if (variable && (!isImplicitGlobal(variable) || hasOwnProperty.call(variable, "writeable"))) {
return variable;
}
return null;
}
/**
* Checks if the given node is the argument of a typeof operator.
* @param {ASTNode} node The AST node being checked.
* @returns {boolean} Whether or not the node is the argument of a typeof operator.
*/
function hasTypeOfOperator(node) {
var parent = node.parent;
return parent.type === "UnaryExpression" && parent.operator === "typeof";
}
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------
module.exports = function(context) {
var NOT_DEFINED_MESSAGE = "\"{{name}}\" is not defined.",
READ_ONLY_MESSAGE = "\"{{name}}\" is read only.";
var options = context.options[0];
var considerTypeOf = options && options.typeof === true || false;
return {
"Program:exit": function(/* node */) {
var globalScope = context.getScope();
globalScope.through.forEach(function(ref) {
var variable = getDeclaredGlobalVariable(globalScope, ref),
name = ref.identifier.name;
if (hasTypeOfOperator(ref.identifier) && !considerTypeOf) {
return;
}
if (!variable) {
context.report(ref.identifier, NOT_DEFINED_MESSAGE, { name: name });
} else if (ref.isWrite() && variable.writeable === false) {
context.report(ref.identifier, READ_ONLY_MESSAGE, { name: name });
}
});
}
};
};
module.exports.schema = [
{
"type": "object",
"properties": {
"typeof": {
"type": "boolean"
}
},
"additionalProperties": false
}
];