Big merge from experimental to bleeding edge.

utils/pub/utils.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.
 
 /// Generic utility functions. Stuff that should possibly be in core.
 library utils;
 
+import 'dart:async';
 import 'dart:crypto';
 import 'dart:isolate';
 import 'dart:uri';
 
 /// A pair of values.
 class Pair<E, F> {
   E first;
   F last;
 
   Pair(this.first, this.last);
@@ skipping 17 matching lines @@
   while (result.length < length) {
     result.add(' ');
   }
 
   return result.toString();
 }
 
 /// Runs [fn] after [future] completes, whether it completes successfully or
 /// not. Essentially an asynchronous `finally` block.
 always(Future future, fn()) {
-  var completer = new Completer();
-  future.then((_) => fn());
-  future.handleException((_) {
-    fn();
-    return false;
-  });
+  future.catchError((_) {}).then((_) => fn());
 }
 
-/// Flattens nested collections into a single list containing only non-list
-/// elements.
-List flatten(Collection nested) {
+/// Flattens nested lists inside an iterable into a single list containing only
+/// non-list elements.
+List flatten(Iterable nested) {
   var result = [];
   helper(list) {
     for (var element in list) {
       if (element is List) {
         helper(element);
       } else {
         result.add(element);
       }
     }
   }
   helper(nested);
   return result;
 }
 
 /// Asserts that [iter] contains only one element, and returns it.
 only(Iterable iter) {
-  var iterator = iter.iterator();
-  assert(iterator.hasNext);
-  var obj = iterator.next();
-  assert(!iterator.hasNext);
+  var iterator = iter.iterator;
+  var currentIsValid = iterator.moveNext();
+  assert(currentIsValid);
+  var obj = iterator.current;
+  assert(!iterator.moveNext());
   return obj;
 }
 
 /// Returns a set containing all elements in [minuend] that are not in
 /// [subtrahend].
 Set setMinus(Collection minuend, Collection subtrahend) {
   var minuendSet = new Set.from(minuend);
   minuendSet.removeAll(subtrahend);
   return minuendSet;
 }
@@ skipping 15 matching lines @@
 /// Returns whether or not [str] ends with [matcher].
 bool endsWithPattern(String str, Pattern matcher) {
   for (var match in matcher.allMatches(str)) {
     if (match.end == str.length) return true;
   }
   return false;
 }
 
 /// Returns the hex-encoded sha1 hash of [source].
 String sha1(String source) =>
-  CryptoUtils.bytesToHex(new SHA1().update(source.charCodes).digest());
+  CryptoUtils.bytesToHex(new SHA1().add(source.charCodes).close());
 
 /// Returns a [Future] that completes in [milliseconds].
 Future sleep(int milliseconds) {
   var completer = new Completer();
   new Timer(milliseconds, completer.complete);
   return completer.future;
 }
 
 /// Configures [future] so that its result (success or exception) is passed on
 /// to [completer].
 void chainToCompleter(Future future, Completer completer) {
-  future.handleException((e) {
-    completer.completeException(e, future.stackTrace);
-    return true;
-  });
-  future.then(completer.complete);
+  future
+    .then(completer.complete)
+    .catchError((e) {
+      completer.completeError(e.error, e.stackTrace);
+    });
 }
 
 // TODO(nweiz): unify the following functions with the utility functions in
 // pkg/http.
 
 /// Like [String.split], but only splits on the first occurrence of the pattern.
 /// This will always return an array of two elements or fewer.
 List<String> split1(String toSplit, String pattern) {
   if (toSplit.isEmpty) return <String>[];
 
@@ skipping 26 matching lines @@
 }
 
 /// Convert a [Map] from parameter names to values to a URL query string.
 String mapToQuery(Map<String, String> map) {
   var pairs = <List<String>>[];
   map.forEach((key, value) {
     key = encodeUriComponent(key);
     value = (value == null || value.isEmpty) ? null : encodeUriComponent(value);
     pairs.add([key, value]);
   });
-  return Strings.join(pairs.map((pair) {
+  return Strings.join(pairs.mappedBy((pair) {
     if (pair[1] == null) return pair[0];
     return "${pair[0]}=${pair[1]}";
   }), "&");
 }
 
 /// Add all key/value pairs from [source] to [destination], overwriting any
 /// pre-existing values.
 void mapAddAll(Map destination, Map source) =>
   source.forEach((key, value) => destination[key] = value);
 
 /// Decodes a URL-encoded string. Unlike [decodeUriComponent], this includes
 /// replacing `+` with ` `.
 String urlDecode(String encoded) =>
   decodeUriComponent(encoded.replaceAll("+", " "));