48 lines
1.2 KiB
JavaScript
48 lines
1.2 KiB
JavaScript
|
/**
|
||
|
* Copyright (c) 2013-present, Facebook, Inc.
|
||
|
* All rights reserved.
|
||
|
*
|
||
|
* This source code is licensed under the BSD-style license found in the
|
||
|
* LICENSE file in the root directory of this source tree. An additional grant
|
||
|
* of patent rights can be found in the PATENTS file in the same directory.
|
||
|
*/
|
||
|
|
||
|
'use strict';
|
||
|
|
||
|
module.exports = function(babel) {
|
||
|
const t = babel.types;
|
||
|
|
||
|
// We can't construct an identifier with a type annotation all in 1 fell swoop
|
||
|
// so we have to create & mutate, then pass along.
|
||
|
const DEV_IDENTIFIER = t.identifier('__DEV__');
|
||
|
DEV_IDENTIFIER.typeAnnotation = t.typeAnnotation(t.booleanTypeAnnotation());
|
||
|
const DEV_DECLARATION = t.declareVariable(
|
||
|
DEV_IDENTIFIER
|
||
|
);
|
||
|
|
||
|
return {
|
||
|
pre() {
|
||
|
this.usesDEV = false;
|
||
|
},
|
||
|
|
||
|
visitor: {
|
||
|
Identifier: {
|
||
|
enter(path, file) {
|
||
|
this.usesDEV = this.usesDEV || path.isIdentifier({name: '__DEV__'});
|
||
|
},
|
||
|
},
|
||
|
|
||
|
Program: {
|
||
|
exit(path, file) {
|
||
|
if (!this.usesDEV) {
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
// Add the declaration at the front of the body if we've used __DEV__.
|
||
|
path.node.body.unshift(DEV_DECLARATION);
|
||
|
},
|
||
|
},
|
||
|
},
|
||
|
};
|
||
|
};
|