Remove deprecated declarations.

Keep `.whereNotNull`. It's deprecation is fairly new.
Deprecate `IterableZip` in anticipation of getting `.zip`
in the platform libraries.

Author: lrhn

pkgs/collection/CHANGELOG.md

@@ -1,3 +1,13 @@
+## 2.0.0
+
+- Breaking changes:
+  - Adds `final`, `base` and `interface` to classes intended to be so.
+  - Removes deprecated declarations. Most has been replaced by functionality
+    in the platform libraries, or better functionality in other libraries.
+  - Removes deprecated top-level libraries.
+    Implement `package:collection/collection.dart` and use `show` or `hide`
+    to control the imported names if necessary, or desired.
+
 ## 1.19.1
 
 - Move to `dart-lang/core` monorepo.

pkgs/collection/lib/algorithms.dart

@@ -156,9 +156,6 @@ class CanonicalizedMap<C, K, V> implements Map<K, V> {
   void removeWhere(bool Function(K key, V value) test) =>
       _base.removeWhere((_, pair) => test(pair.key, pair.value));
 
-  @Deprecated('Use cast instead')
-  Map<K2, V2> retype<K2, V2>() => cast<K2, V2>();
-
   @override
   V update(K key, V Function(V) update, {V Function()? ifAbsent}) =>
       _base.update(_canonicalize(key), (pair) {

pkgs/collection/lib/equality.dart

@@ -151,6 +151,12 @@ int compareAsciiLowerCase(String a, String b) {
 /// ordering, where lexical ordering would put the `1` before the `7`, ignoring
 /// that the `1` is part of a larger number.
 ///
+/// If a digit sequence differs only in the number of leading zeros,
+/// and therefore have the same numerical value, the one with
+/// fewer leading zeros is ordered before the one with more.
+///
+/// Numbers are unsigned. A prior `-` is not considered a minus sign.
+///
 /// Example:
 /// The following strings are in the order they would be sorted by using this
 /// comparison function:

pkgs/collection/lib/iterable_zip.dart

@@ -27,9 +27,6 @@ class EmptyUnmodifiableSet<E> extends IterableBase<E>
   Iterable<E> followedBy(Iterable<E> other) => DelegatingIterable(other);
   @override
   E? lookup(Object? element) => null;
-  @Deprecated('Use cast instead')
-  @override
-  EmptyUnmodifiableSet<T> retype<T>() => EmptyUnmodifiableSet<T>();
   @override
   E singleWhere(bool Function(E) test, {E Function()? orElse}) =>
       orElse != null ? orElse() : throw StateError('No element');

pkgs/collection/lib/priority_queue.dart

@@ -5,25 +5,9 @@
 import 'dart:collection';
 import 'dart:math' as math;
 
+import 'list_extensions.dart' show ListExtensions; // For `reverseRange`.
 import 'utils.dart';
 
-/// Creates a new map from [map] with new keys and values.
-///
-/// The return values of [key] are used as the keys and the return values of
-/// [value] are used as the values for the new map.
-@Deprecated('Use Map.map or a for loop in a Map literal.')
-Map<K2, V2> mapMap<K1, V1, K2, V2>(Map<K1, V1> map,
-    {K2 Function(K1, V1)? key, V2 Function(K1, V1)? value}) {
-  var keyFn = key ?? (mapKey, _) => mapKey as K2;
-  var valueFn = value ?? (_, mapValue) => mapValue as V2;
-
-  var result = <K2, V2>{};
-  map.forEach((mapKey, mapValue) {
-    result[keyFn(mapKey, mapValue)] = valueFn(mapKey, mapValue);
-  });
-  return result;
-}
-
 /// Returns a new map with all key/value pairs in both [map1] and [map2].
 ///
 /// If there are keys that occur in both maps, the [value] function is used to
@@ -109,45 +93,6 @@ S? maxBy<S, T>(Iterable<S> values, T Function(S) orderBy,
   return maxValue;
 }
 
-/// Returns the [transitive closure][] of [graph].
-///
-/// [transitive closure]: https://en.wikipedia.org/wiki/Transitive_closure
-///
-/// Interprets [graph] as a directed graph with a vertex for each key and edges
-/// from each key to the values that the key maps to.
-///
-/// Assumes that every vertex in the graph has a key to represent it, even if
-/// that vertex has no outgoing edges. This isn't checked, but if it's not
-/// satisfied, the function may crash or provide unexpected output. For example,
-/// `{"a": ["b"]}` is not valid, but `{"a": ["b"], "b": []}` is.
-@Deprecated('This method will be removed. Consider using package:graphs.')
-Map<T, Set<T>> transitiveClosure<T>(Map<T, Iterable<T>> graph) {
-  // This uses [Warshall's algorithm][], modified not to add a vertex from each
-  // node to itself.
-  //
-  // [Warshall's algorithm]: https://en.wikipedia.org/wiki/Floyd%E2%80%93Warshall_algorithm#Applications_and_generalizations.
-  var result = <T, Set<T>>{};
-  graph.forEach((vertex, edges) {
-    result[vertex] = Set<T>.from(edges);
-  });
-
-  // Lists are faster to iterate than maps, so we create a list since we're
-  // iterating repeatedly.
-  var keys = graph.keys.toList();
-  for (var vertex1 in keys) {
-    for (var vertex2 in keys) {
-      for (var vertex3 in keys) {
-        if (result[vertex2]!.contains(vertex1) &&
-            result[vertex1]!.contains(vertex3)) {
-          result[vertex2]!.add(vertex3);
-        }
-      }
-    }
-  }
-
-  return result;
-}
-
 /// Returns the [strongly connected components][] of [graph], in topological
 /// order.
 ///
@@ -209,5 +154,5 @@ List<Set<T>> stronglyConnectedComponents<T>(Map<T, Iterable<T>> graph) {
 
   // Tarjan's algorithm produces a reverse-topological sort, so we reverse it to
   // get a normal topological sort.
-  return result.reversed.toList();
+  return result..reverseRange(0, result.length);
 }

pkgs/collection/lib/src/canonicalized_map.dart

@@ -13,6 +13,7 @@ import 'dart:collection';
 /// combined into a single list, which becomes the next value of this
 /// [Iterable]'s [Iterator]. As soon as any of the iterators run out,
 /// the zipped iterator also stops.
+@Deprecated('Use [i1, i2].zip from dart:collection')
 class IterableZip<T> extends IterableBase<List<T>> {
   final Iterable<Iterable<T>> _iterables;