blob: 0ecd442e86e4b9cb3be23c4dbf66fa9e3a23dc8c [file] [log] [blame]
// Copyright (c) 2017, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
library _fe_analyzer_shared.util.relativize;
import 'dart:math';
/// Detect if we're on Windows without importing `dart:io`.
bool isWindows = new Uri.directory("C:\\").path ==
new Uri.directory("C:\\", windows: true).path;
String relativizeUri(Uri base, Uri uri, bool isWindows) {
bool equalsNCS(String a, String b) {
return a.toLowerCase() == b.toLowerCase();
}
if (!equalsNCS(base.scheme, uri.scheme) ||
equalsNCS(base.scheme, 'dart') ||
equalsNCS(base.scheme, 'package')) {
return uri.toString();
}
if (!equalsNCS(base.scheme, 'file')) {
isWindows = false;
}
String normalize(String path) {
if (isWindows) {
return path.toLowerCase();
} else {
return path;
}
}
if (base.userInfo == uri.userInfo &&
equalsNCS(base.host, uri.host) &&
base.port == uri.port &&
uri.query == "" &&
uri.fragment == "") {
if (normalize(uri.path).startsWith(normalize(base.path))) {
return uri.path.substring(base.path.lastIndexOf('/') + 1);
}
if (!base.path.startsWith('/') || !uri.path.startsWith('/')) {
return uri.toString();
}
List<String> uriParts = uri.path.split('/');
List<String> baseParts = base.path.split('/');
int common = 0;
int length = min(uriParts.length, baseParts.length);
while (common < length &&
normalize(uriParts[common]) == normalize(baseParts[common])) {
common++;
}
if (common == 1 || (isWindows && common == 2)) {
// The first part will always be an empty string because the
// paths are absolute. On Windows, we must also consider drive
// letters or hostnames.
if (baseParts.length > common + 1) {
// Avoid using '..' to go to the root, unless we are already there.
return uri.path;
}
}
StringBuffer sb = new StringBuffer();
for (int i = common + 1; i < baseParts.length; i++) {
sb.write('../');
}
for (int i = common; i < uriParts.length - 1; i++) {
sb.write('${uriParts[i]}/');
}
sb.write('${uriParts.last}');
return sb.toString();
}
return uri.toString();
}