index.js
2.93 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
"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = simplifyAccess;
var _t = require("@babel/types");
const {
LOGICAL_OPERATORS,
assignmentExpression,
binaryExpression,
cloneNode,
identifier,
logicalExpression,
numericLiteral,
sequenceExpression,
unaryExpression
} = _t;
const simpleAssignmentVisitor = {
UpdateExpression: {
exit(path) {
const {
scope,
bindingNames,
includeUpdateExpression
} = this;
if (!includeUpdateExpression) {
return;
}
const arg = path.get("argument");
if (!arg.isIdentifier()) return;
const localName = arg.node.name;
if (!bindingNames.has(localName)) return;
if (scope.getBinding(localName) !== path.scope.getBinding(localName)) {
return;
}
if (path.parentPath.isExpressionStatement() && !path.isCompletionRecord()) {
const operator = path.node.operator == "++" ? "+=" : "-=";
path.replaceWith(assignmentExpression(operator, arg.node, numericLiteral(1)));
} else if (path.node.prefix) {
path.replaceWith(assignmentExpression("=", identifier(localName), binaryExpression(path.node.operator[0], unaryExpression("+", arg.node), numericLiteral(1))));
} else {
const old = path.scope.generateUidIdentifierBasedOnNode(arg.node, "old");
const varName = old.name;
path.scope.push({
id: old
});
const binary = binaryExpression(path.node.operator[0], identifier(varName),
numericLiteral(1));
path.replaceWith(sequenceExpression([assignmentExpression("=", identifier(varName), unaryExpression("+", arg.node)), assignmentExpression("=", cloneNode(arg.node), binary), identifier(varName)]));
}
}
},
AssignmentExpression: {
exit(path) {
const {
scope,
seen,
bindingNames
} = this;
if (path.node.operator === "=") return;
if (seen.has(path.node)) return;
seen.add(path.node);
const left = path.get("left");
if (!left.isIdentifier()) return;
const localName = left.node.name;
if (!bindingNames.has(localName)) return;
if (scope.getBinding(localName) !== path.scope.getBinding(localName)) {
return;
}
const operator = path.node.operator.slice(0, -1);
if (LOGICAL_OPERATORS.includes(operator)) {
path.replaceWith(logicalExpression(
operator, path.node.left, assignmentExpression("=", cloneNode(path.node.left), path.node.right)));
} else {
path.node.right = binaryExpression(
operator, cloneNode(path.node.left), path.node.right);
path.node.operator = "=";
}
}
}
};
function simplifyAccess(path, bindingNames,
includeUpdateExpression = true) {
path.traverse(simpleAssignmentVisitor, {
scope: path.scope,
bindingNames,
seen: new WeakSet(),
includeUpdateExpression
});
}
//# sourceMappingURL=index.js.map