Copy URI top-level helpers to separate file.

dart/lib/uri/helpers.dart

 // Copyright (c) 2012, 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('uri');
-
-/**
- * A parsed URI, inspired by Closure's [URI][] class. Implements [RFC-3986][].
- * [uri]: http://closure-library.googlecode.com/svn/docs/class_goog_Uri.html
- * [RFC-3986]: http://tools.ietf.org/html/rfc3986#section-4.3)
- */
-class Uri {
-  final String scheme;
-  final String userInfo;
-  final String domain;
-  final int port;
-  final String path;
-  final String query;
-  final String fragment;
-
-  Uri.fromString(String uri) : this._fromMatch(_splitRe.firstMatch(uri));
-
-  Uri._fromMatch(Match m) : this(_emptyIfNull(m[_COMPONENT_SCHEME]),
-                                 _emptyIfNull(m[_COMPONENT_USER_INFO]),
-                                 _emptyIfNull(m[_COMPONENT_DOMAIN]),
-                                 _parseIntOrZero(m[_COMPONENT_PORT]),
-                                 _emptyIfNull(m[_COMPONENT_PATH]),
-                                 _emptyIfNull(m[_COMPONENT_QUERY_DATA]),
-                                 _emptyIfNull(m[_COMPONENT_FRAGMENT]));
-
-  const Uri([String this.scheme = "", String this.userInfo ="",
-             String this.domain = "", int this.port = 0,
-             String this.path = "", String this.query = "",
-             String this.fragment = ""]);
-
-  static String _emptyIfNull(String val) => val != null ? val : '';
-
-  static int _parseIntOrZero(String val) {
-    if (val !== null && val != '') {
-      return Math.parseInt(val);
-    } else {
-      return 0;
-    }
-  }
-
-  // NOTE: This code was ported from: closure-library/closure/goog/uri/utils.js
-  static final RegExp _splitRe = const RegExp(
-      '^'
-      '(?:'
-        '([^:/?#.]+)'                   // scheme - ignore special characters
-                                        // used by other URL parts such as :,
-                                        // ?, /, #, and .
-      ':)?'
-      '(?://'
-        '(?:([^/?#]*)@)?'               // userInfo
-        '([\\w\\d\\-\\u0100-\\uffff.%]*)'
-                                        // domain - restrict to letters,
-                                        // digits, dashes, dots, percent
-                                        // escapes, and unicode characters.
-        '(?::([0-9]+))?'                // port
-      ')?'
-      '([^?#]+)?'                       // path
-      '(?:\\?([^#]*))?'                 // query
-      '(?:#(.*))?'                      // fragment
-      '\$');
-
-  static final _COMPONENT_SCHEME = 1;
-  static final _COMPONENT_USER_INFO = 2;
-  static final _COMPONENT_DOMAIN = 3;
-  static final _COMPONENT_PORT = 4;
-  static final _COMPONENT_PATH = 5;
-  static final _COMPONENT_QUERY_DATA = 6;
-  static final _COMPONENT_FRAGMENT = 7;
-
-  /**
-   * Returns `true` if the URI is absolute.
-   */
-  bool isAbsolute() {
-    if ("" == scheme) return false;
-    if ("" != fragment) return false;
-    return true;
-
-    /* absolute-URI  = scheme ":" hier-part [ "?" query ]
-     * hier-part   = "//" authority path-abempty
-     *             / path-absolute
-     *             / path-rootless
-     *             / path-empty
-     *
-     * path          = path-abempty    ; begins with "/" or is empty
-     *               / path-absolute   ; begins with "/" but not "//"
-     *               / path-noscheme   ; begins with a non-colon segment
-     *               / path-rootless   ; begins with a segment
-     *               / path-empty      ; zero characters
-     *
-     * path-abempty  = *( "/" segment )
-     * path-absolute = "/" [ segment-nz *( "/" segment ) ]
-     * path-noscheme = segment-nz-nc *( "/" segment )
-     * path-rootless = segment-nz *( "/" segment )
-     * path-empty    = 0<pchar>
-     * segment       = *pchar
-     * segment-nz    = 1*pchar
-     * segment-nz-nc = 1*( unreserved / pct-encoded / sub-delims / "@" )
-     *               ; non-zero-length segment without any colon ":"
-     *
-     * pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
-     */
-  }
-
-  Uri resolve(String uri) {
-    return resolveUri(new Uri.fromString(uri));
-  }
-
-  Uri resolveUri(Uri reference) {
-    // From RFC 3986.
-    String targetScheme;
-    String targetUserInfo;
-    String targetDomain;
-    int targetPort;
-    String targetPath;
-    String targetQuery;
-    if (reference.scheme != "") {
-      targetScheme = reference.scheme;
-      targetUserInfo = reference.userInfo;
-      targetDomain = reference.domain;
-      targetPort = reference.port;
-      targetPath = removeDotSegments(reference.path);
-      targetQuery = reference.query;
-    } else {
-      if (reference.hasAuthority()) {
-        targetUserInfo = reference.userInfo;
-        targetDomain = reference.domain;
-        targetPort = reference.port;
-        targetPath = removeDotSegments(reference.path);
-        targetQuery = reference.query;
-      } else {
-        if (reference.path == "") {
-          targetPath = this.path;
-          if (reference.query != "") {
-            targetQuery = reference.query;
-          } else {
-            targetQuery = this.query;
-          }
-        } else {
-          if (reference.path.startsWith("/")) {
-            targetPath = removeDotSegments(reference.path);
-          } else {
-            targetPath = removeDotSegments(merge(this.path, reference.path));
-          }
-          targetQuery = reference.query;
-        }
-        targetUserInfo = this.userInfo;
-        targetDomain = this.domain;
-        targetPort = this.port;
-      }
-      targetScheme = this.scheme;
-    }
-    return new Uri(targetScheme, targetUserInfo, targetDomain, targetPort,
-                   targetPath, targetQuery, reference.fragment);
-  }
-
-  bool hasAuthority() {
-    return (userInfo != "") || (domain != "") || (port != 0);
-  }
-
-  String toString() {
-    StringBuffer sb = new StringBuffer();
-    _addIfNonEmpty(sb, scheme, scheme, ':');
-    if (hasAuthority() || (scheme == "file")) {
-      sb.add("//");
-      _addIfNonEmpty(sb, userInfo, userInfo, "@");
-      sb.add(domain === null ? "null" : domain);
-      if (port != 0) {
-        sb.add(":");
-        sb.add(port.toString());
-      }
-    }
-    sb.add(path === null ? "null" : path);
-    _addIfNonEmpty(sb, query, "?", query);
-    _addIfNonEmpty(sb, fragment, "#", fragment);
-    return sb.toString();
-  }
-
-  static void _addIfNonEmpty(StringBuffer sb, String test,
-                             String first, String second) {
-    if ("" != test) {
-      sb.add(first === null ? "null" : first);
-      sb.add(second === null ? "null" : second);
-    }
-  }
-}
-
 String merge(String base, String reference) {
   if (base == "") return "/$reference";
   return "${base.substring(0, base.lastIndexOf("/") + 1)}$reference";
 }
 
 String removeDotSegments(String path) {
   List<String> output = [];
   bool appendSlash = false;
   for (String segment in path.split("/")) {
     appendSlash = false;
     if (segment == "..") {
       if (!output.isEmpty() &&
           ((output.length != 1) || (output[0] != ""))) output.removeLast();
       appendSlash = true;
     } else if ("." == segment) {
       appendSlash = true;
     } else {
       output.add(segment);
     }
   }
   if (appendSlash) output.add("");
   return Strings.join(output, "/");
 }