react-native/local-cli/util/copyAndReplace.js

141 lines
3.7 KiB
JavaScript
Raw Normal View History

/**
* Copyright (c) 2015-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @format
*/
'use strict';
const fs = require('fs');
const path = require('path');
// Binary files, don't process these (avoid decoding as utf8)
const binaryExtensions = ['.png', '.jar'];
/**
* Copy a file to given destination, replacing parts of its contents.
* @param srcPath Path to a file to be copied.
* @param destPath Destination path.
* @param replacements: e.g. {'TextToBeReplaced': 'Replacement'}
* @param contentChangedCallback
* Used when upgrading projects. Based on if file contents would change
* when being replaced, allows the caller to specify whether the file
* should be replaced or not.
* If null, files will be overwritten.
* Function(path, 'identical' | 'changed' | 'new') => 'keep' | 'overwrite'
*/
function copyAndReplace(
srcPath,
destPath,
replacements,
contentChangedCallback,
) {
if (fs.lstatSync(srcPath).isDirectory()) {
if (!fs.existsSync(destPath)) {
fs.mkdirSync(destPath);
}
// Not recursive
return;
}
const extension = path.extname(srcPath);
if (binaryExtensions.indexOf(extension) !== -1) {
// Binary file
let shouldOverwrite = 'overwrite';
if (contentChangedCallback) {
const newContentBuffer = fs.readFileSync(srcPath);
let contentChanged = 'identical';
try {
const origContentBuffer = fs.readFileSync(destPath);
if (Buffer.compare(origContentBuffer, newContentBuffer) !== 0) {
contentChanged = 'changed';
}
} catch (err) {
if (err.code === 'ENOENT') {
contentChanged = 'new';
} else {
throw err;
}
}
shouldOverwrite = contentChangedCallback(destPath, contentChanged);
}
if (shouldOverwrite === 'overwrite') {
copyBinaryFile(srcPath, destPath, err => {
if (err) {
throw err;
}
});
}
} else {
// Text file
const srcPermissions = fs.statSync(srcPath).mode;
let content = fs.readFileSync(srcPath, 'utf8');
Object.keys(replacements).forEach(
regex =>
(content = content.replace(
new RegExp(regex, 'g'),
replacements[regex],
)),
);
let shouldOverwrite = 'overwrite';
if (contentChangedCallback) {
// Check if contents changed and ask to overwrite
let contentChanged = 'identical';
try {
const origContent = fs.readFileSync(destPath, 'utf8');
if (content !== origContent) {
//console.log('Content changed: ' + destPath);
contentChanged = 'changed';
}
} catch (err) {
if (err.code === 'ENOENT') {
contentChanged = 'new';
} else {
throw err;
}
}
shouldOverwrite = contentChangedCallback(destPath, contentChanged);
}
if (shouldOverwrite === 'overwrite') {
fs.writeFileSync(destPath, content, {
encoding: 'utf8',
mode: srcPermissions,
});
}
}
}
/**
* Same as 'cp' on Unix. Don't do any replacements.
*/
function copyBinaryFile(srcPath, destPath, cb) {
let cbCalled = false;
const srcPermissions = fs.statSync(srcPath).mode;
const readStream = fs.createReadStream(srcPath);
readStream.on('error', function(err) {
done(err);
});
const writeStream = fs.createWriteStream(destPath, {
mode: srcPermissions,
});
writeStream.on('error', function(err) {
done(err);
});
writeStream.on('close', function(ex) {
done();
});
readStream.pipe(writeStream);
function done(err) {
if (!cbCalled) {
cb(err);
cbCalled = true;
}
}
}
module.exports = copyAndReplace;