/
index.js
56 lines (45 loc) 路 1.42 KB
/
index.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
import syntaxFunctionSent from "@babel/plugin-syntax-function-sent";
import wrapFunction from "@babel/helper-wrap-function";
export default function({ types: t }) {
const isFunctionSent = node =>
t.isIdentifier(node.meta, { name: "function" }) &&
t.isIdentifier(node.property, { name: "sent" });
const yieldVisitor = {
Function(path) {
path.skip();
},
YieldExpression(path) {
const replaced = t.isAssignmentExpression(path.parent, {
left: this.sentId,
});
if (!replaced) {
path.replaceWith(t.assignmentExpression("=", this.sentId, path.node));
}
},
MetaProperty(path) {
if (isFunctionSent(path.node)) {
path.replaceWith(this.sentId);
}
},
};
return {
inherits: syntaxFunctionSent,
visitor: {
MetaProperty(path, state) {
if (!isFunctionSent(path.node)) return;
const fnPath = path.getFunctionParent();
if (!fnPath.node.generator) {
throw new Error("Parent generator function not found");
}
const sentId = path.scope.generateUidIdentifier("function.sent");
fnPath.traverse(yieldVisitor, { sentId });
fnPath.node.body.body.unshift(
t.variableDeclaration("let", [
t.variableDeclarator(sentId, t.yieldExpression()),
]),
);
wrapFunction(fnPath, state.addHelper("skipFirstGeneratorNext"));
},
},
};
}