diff --git a/pkgs/collection/CHANGELOG.md b/pkgs/collection/CHANGELOG.md
index 30f8c3f7a..dbffb8ccb 100644
--- a/pkgs/collection/CHANGELOG.md
+++ b/pkgs/collection/CHANGELOG.md
@@ -1,3 +1,12 @@
+## 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 Most has been replaced by functionality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.
 
 ## 1.20.0-wip
 
diff --git a/pkgs/collection/lib/algorithms.dart b/pkgs/collection/lib/algorithms.dart
deleted file mode 100644
index ac4324239..000000000
--- a/pkgs/collection/lib/algorithms.dart
+++ /dev/null
@@ -1,10 +0,0 @@
-// Copyright (c) 2013, 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.
-
-/// Import `collection.dart` instead.
-@Deprecated('Will be removed in collection 2.0.0.')
-library;
-
-export 'src/algorithms.dart'
-    show binarySearch, insertionSort, lowerBound, mergeSort, reverse, shuffle;
diff --git a/pkgs/collection/lib/equality.dart b/pkgs/collection/lib/equality.dart
deleted file mode 100644
index 5dc158cae..000000000
--- a/pkgs/collection/lib/equality.dart
+++ /dev/null
@@ -1,9 +0,0 @@
-// Copyright (c) 2013, 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.
-
-/// Import `collection.dart` instead.
-@Deprecated('Will be removed in collection 2.0.0.')
-library;
-
-export 'src/equality.dart';
diff --git a/pkgs/collection/lib/iterable_zip.dart b/pkgs/collection/lib/iterable_zip.dart
deleted file mode 100644
index bd0b1ef09..000000000
--- a/pkgs/collection/lib/iterable_zip.dart
+++ /dev/null
@@ -1,9 +0,0 @@
-// Copyright (c) 2013, 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.
-
-/// Import `collection.dart` instead.
-@Deprecated('Will be removed in collection 2.0.0.')
-library;
-
-export 'src/iterable_zip.dart';
diff --git a/pkgs/collection/lib/priority_queue.dart b/pkgs/collection/lib/priority_queue.dart
deleted file mode 100644
index 7505ce479..000000000
--- a/pkgs/collection/lib/priority_queue.dart
+++ /dev/null
@@ -1,9 +0,0 @@
-// Copyright (c) 2014, 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.
-
-/// Import `collection.dart` instead.
-@Deprecated('Will be removed in collection 2.0.0.')
-library;
-
-export 'src/priority_queue.dart';
diff --git a/pkgs/collection/lib/src/boollist.dart b/pkgs/collection/lib/src/boollist.dart
index b026d858a..b7b1893da 100644
--- a/pkgs/collection/lib/src/boollist.dart
+++ b/pkgs/collection/lib/src/boollist.dart
@@ -10,7 +10,7 @@ import 'unmodifiable_wrappers.dart' show NonGrowableListMixin;
 /// A space-efficient list of boolean values.
 ///
 /// Uses list of integers as internal storage to reduce memory usage.
-abstract /*mixin*/ class BoolList with ListMixin<bool> {
+abstract final class BoolList with ListMixin<bool> {
   static const int _entryShift = 5;
 
   static const int _bitsPerEntry = 32;
@@ -180,7 +180,7 @@ abstract /*mixin*/ class BoolList with ListMixin<bool> {
   }
 }
 
-class _GrowableBoolList extends BoolList {
+final class _GrowableBoolList extends BoolList {
   static const int _growthFactor = 2;
 
   _GrowableBoolList._withCapacity(int length, int capacity)
@@ -228,7 +228,8 @@ class _GrowableBoolList extends BoolList {
   }
 }
 
-class _NonGrowableBoolList extends BoolList with NonGrowableListMixin<bool> {
+final class _NonGrowableBoolList extends BoolList
+    with NonGrowableListMixin<bool> {
   _NonGrowableBoolList._withCapacity(int length, int capacity)
       : super._(
           Uint32List(BoolList._lengthInWords(capacity)),
diff --git a/pkgs/collection/lib/src/canonicalized_map.dart b/pkgs/collection/lib/src/canonicalized_map.dart
index 3dc6e37cb..7db44fd7d 100644
--- a/pkgs/collection/lib/src/canonicalized_map.dart
+++ b/pkgs/collection/lib/src/canonicalized_map.dart
@@ -4,12 +4,15 @@
 
 import 'dart:collection';
 
+import 'package:meta/meta.dart';
+
 /// A map whose keys are converted to canonical values of type `C`.
 ///
 /// This is useful for using case-insensitive String keys, for example. It's
 /// more efficient than a [LinkedHashMap] with a custom equality operator
 /// because it only canonicalizes each key once, rather than doing so for each
 /// comparison.
+@sealed // TODO: Make `final` when no longer extended.
 class CanonicalizedMap<C, K, V> implements Map<K, V> {
   final C Function(K) _canonicalize;
 
@@ -25,9 +28,10 @@ class CanonicalizedMap<C, K, V> implements Map<K, V> {
   /// The [isValidKey] function is called before calling [canonicalize] for
   /// methods that take arbitrary objects. It can be used to filter out keys
   /// that can't be canonicalized.
-  CanonicalizedMap(C Function(K key) canonicalize,
-      {bool Function(K key)? isValidKey})
-      : _canonicalize = canonicalize,
+  CanonicalizedMap(
+    C Function(K key) canonicalize, {
+    bool Function(K key)? isValidKey,
+  })  : _canonicalize = canonicalize,
         _isValidKeyFn = isValidKey;
 
   /// Creates a canonicalized map that is initialized with the key/value pairs
@@ -39,9 +43,11 @@ class CanonicalizedMap<C, K, V> implements Map<K, V> {
   /// The [isValidKey] function is called before calling [canonicalize] for
   /// methods that take arbitrary objects. It can be used to filter out keys
   /// that can't be canonicalized.
-  CanonicalizedMap.from(Map<K, V> other, C Function(K key) canonicalize,
-      {bool Function(K key)? isValidKey})
-      : _canonicalize = canonicalize,
+  CanonicalizedMap.from(
+    Map<K, V> other,
+    C Function(K key) canonicalize, {
+    bool Function(K key)? isValidKey,
+  })  : _canonicalize = canonicalize,
         _isValidKeyFn = isValidKey {
     addAll(other);
   }
@@ -56,15 +62,19 @@ class CanonicalizedMap<C, K, V> implements Map<K, V> {
   /// methods that take arbitrary objects. It can be used to filter out keys
   /// that can't be canonicalized.
   CanonicalizedMap.fromEntries(
-      Iterable<MapEntry<K, V>> entries, C Function(K key) canonicalize,
-      {bool Function(K key)? isValidKey})
-      : _canonicalize = canonicalize,
+    Iterable<MapEntry<K, V>> entries,
+    C Function(K key) canonicalize, {
+    bool Function(K key)? isValidKey,
+  })  : _canonicalize = canonicalize,
         _isValidKeyFn = isValidKey {
     addEntries(entries);
   }
 
   CanonicalizedMap._(
-      this._canonicalize, this._isValidKeyFn, Map<C, MapEntry<K, V>> base) {
+    this._canonicalize,
+    this._isValidKeyFn,
+    Map<C, MapEntry<K, V>> base,
+  ) {
     _base.addAll(base);
   }
 
@@ -92,8 +102,11 @@ class CanonicalizedMap<C, K, V> implements Map<K, V> {
   }
 
   @override
-  void addEntries(Iterable<MapEntry<K, V>> entries) => _base.addEntries(entries
-      .map((e) => MapEntry(_canonicalize(e.key), MapEntry(e.key, e.value))));
+  void addEntries(Iterable<MapEntry<K, V>> entries) => _base.addEntries(
+        entries.map(
+          (e) => MapEntry(_canonicalize(e.key), MapEntry(e.key, e.value)),
+        ),
+      );
 
   @override
   Map<K2, V2> cast<K2, V2>() => _base.cast<K2, V2>();
@@ -156,19 +169,18 @@ 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) {
-        var value = pair.value;
-        var newValue = update(value);
-        if (identical(newValue, value)) return pair;
-        return MapEntry(key, newValue);
-      },
-          ifAbsent:
-              ifAbsent == null ? null : () => MapEntry(key, ifAbsent())).value;
+      _base.update(
+        _canonicalize(key),
+        (pair) {
+          var value = pair.value;
+          var newValue = update(value);
+          if (identical(newValue, value)) return pair;
+          return MapEntry(key, newValue);
+        },
+        ifAbsent: ifAbsent == null ? null : () => MapEntry(key, ifAbsent()),
+      ).value;
 
   @override
   void updateAll(V Function(K key, V value) update) =>
@@ -196,5 +208,6 @@ class CanonicalizedMap<C, K, V> implements Map<K, V> {
   /// Creates a `Map<C,V>` (with the canonicalized keys).
   /// See [toMap].
   Map<C, V> toMapOfCanonicalKeys() => Map<C, V>.fromEntries(
-      _base.entries.map((e) => MapEntry<C, V>(e.key, e.value.value)));
+        _base.entries.map((e) => MapEntry<C, V>(e.key, e.value.value)),
+      );
 }
diff --git a/pkgs/collection/lib/src/combined_wrappers/combined_iterable.dart b/pkgs/collection/lib/src/combined_wrappers/combined_iterable.dart
index 281f8a28b..8242034ec 100644
--- a/pkgs/collection/lib/src/combined_wrappers/combined_iterable.dart
+++ b/pkgs/collection/lib/src/combined_wrappers/combined_iterable.dart
@@ -13,7 +13,7 @@ import 'combined_iterator.dart';
 /// lazily accessing individual iterable instances. This means that if the
 /// underlying iterables change, the [CombinedIterableView] will reflect those
 /// changes.
-class CombinedIterableView<T> extends IterableBase<T> {
+final class CombinedIterableView<T> extends IterableBase<T> {
   /// The iterables that this combines.
   final Iterable<Iterable<T>> _iterables;
 
diff --git a/pkgs/collection/lib/src/combined_wrappers/combined_iterator.dart b/pkgs/collection/lib/src/combined_wrappers/combined_iterator.dart
index 0d6088a97..3bc6f8517 100644
--- a/pkgs/collection/lib/src/combined_wrappers/combined_iterator.dart
+++ b/pkgs/collection/lib/src/combined_wrappers/combined_iterator.dart
@@ -5,7 +5,7 @@
 /// The iterator for `CombinedIterableView` and `CombinedListView`.
 ///
 /// Moves through each iterable's iterator in sequence.
-class CombinedIterator<T> implements Iterator<T> {
+final class CombinedIterator<T> implements Iterator<T> {
   /// The iterators that this combines, or `null` if done iterating.
   ///
   /// Because this comes from a call to [Iterable.map], it's lazy and will
diff --git a/pkgs/collection/lib/src/combined_wrappers/combined_list.dart b/pkgs/collection/lib/src/combined_wrappers/combined_list.dart
index f0cd44764..c78bd45d5 100644
--- a/pkgs/collection/lib/src/combined_wrappers/combined_list.dart
+++ b/pkgs/collection/lib/src/combined_wrappers/combined_list.dart
@@ -15,7 +15,7 @@ import 'combined_iterator.dart';
 ///
 /// The index operator (`[]`) and [length] property of a [CombinedListView] are
 /// both `O(lists)` rather than `O(1)`. A [CombinedListView] is unmodifiable.
-class CombinedListView<T> extends ListBase<T>
+final class CombinedListView<T> extends ListBase<T>
     implements UnmodifiableListView<T> {
   static Never _throw() {
     throw UnsupportedError('Cannot modify an unmodifiable List');
diff --git a/pkgs/collection/lib/src/combined_wrappers/combined_map.dart b/pkgs/collection/lib/src/combined_wrappers/combined_map.dart
index 18db6e7ed..cdc53fd41 100644
--- a/pkgs/collection/lib/src/combined_wrappers/combined_map.dart
+++ b/pkgs/collection/lib/src/combined_wrappers/combined_map.dart
@@ -19,7 +19,7 @@ import 'combined_iterable.dart';
 ///
 /// The `length` getter is `O(M)` where M is the total number of entries in
 /// all maps, since it has to remove duplicate entries.
-class CombinedMapView<K, V> extends UnmodifiableMapBase<K, V> {
+final class CombinedMapView<K, V> extends UnmodifiableMapBase<K, V> {
   final Iterable<Map<K, V>> _maps;
 
   /// Create a new combined view of multiple maps.
diff --git a/pkgs/collection/lib/src/comparators.dart b/pkgs/collection/lib/src/comparators.dart
index 6e5d36318..e79fd3c3b 100644
--- a/pkgs/collection/lib/src/comparators.dart
+++ b/pkgs/collection/lib/src/comparators.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:
diff --git a/pkgs/collection/lib/src/empty_unmodifiable_set.dart b/pkgs/collection/lib/src/empty_unmodifiable_set.dart
index 74fd39a14..2b1a62321 100644
--- a/pkgs/collection/lib/src/empty_unmodifiable_set.dart
+++ b/pkgs/collection/lib/src/empty_unmodifiable_set.dart
@@ -8,7 +8,7 @@ import 'unmodifiable_wrappers.dart';
 import 'wrappers.dart';
 
 /// An unmodifiable, empty set which can be constant.
-class EmptyUnmodifiableSet<E> extends IterableBase<E>
+final class EmptyUnmodifiableSet<E> extends IterableBase<E>
     with UnmodifiableSetMixin<E>
     implements UnmodifiableSetView<E> {
   const EmptyUnmodifiableSet();
@@ -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');
diff --git a/pkgs/collection/lib/src/equality.dart b/pkgs/collection/lib/src/equality.dart
index 0e1df23da..ce27bf931 100644
--- a/pkgs/collection/lib/src/equality.dart
+++ b/pkgs/collection/lib/src/equality.dart
@@ -9,7 +9,7 @@ import 'comparators.dart';
 const int _hashMask = 0x7fffffff;
 
 /// A generic equality relation on objects.
-abstract class Equality<E> {
+abstract interface class Equality<E> {
   const factory Equality() = DefaultEquality<E>;
 
   /// Compare two elements for being equal.
@@ -46,7 +46,7 @@ abstract class Equality<E> {
 ///
 /// It's also possible to pass an additional equality instance that should be
 /// used to compare the value itself.
-class EqualityBy<E, F> implements Equality<E> {
+final class EqualityBy<E, F> implements Equality<E> {
   final F Function(E) _comparisonKey;
 
   final Equality<F> _inner;
@@ -81,7 +81,7 @@ class EqualityBy<E, F> implements Equality<E> {
 /// Note that [equals] and [hash] take `Object`s rather than `E`s. This allows
 /// `E` to be inferred as `Null` in const contexts where `E` wouldn't be a
 /// compile-time constant, while still allowing the class to be used at runtime.
-class DefaultEquality<E> implements Equality<E> {
+final class DefaultEquality<E> implements Equality<E> {
   const DefaultEquality();
   @override
   bool equals(Object? e1, Object? e2) => e1 == e2;
@@ -92,7 +92,7 @@ class DefaultEquality<E> implements Equality<E> {
 }
 
 /// Equality of objects that compares only the identity of the objects.
-class IdentityEquality<E> implements Equality<E> {
+final class IdentityEquality<E> implements Equality<E> {
   const IdentityEquality();
   @override
   bool equals(E e1, E e2) => identical(e1, e2);
@@ -109,7 +109,7 @@ class IdentityEquality<E> implements Equality<E> {
 /// The [equals] and [hash] methods accepts `null` values,
 /// even if the [isValidKey] returns `false` for `null`.
 /// The [hash] of `null` is `null.hashCode`.
-class IterableEquality<E> implements Equality<Iterable<E>> {
+final class IterableEquality<E> implements Equality<Iterable<E>> {
   final Equality<E?> _elementEquality;
   const IterableEquality(
       [Equality<E> elementEquality = const DefaultEquality<Never>()])
@@ -161,7 +161,7 @@ class IterableEquality<E> implements Equality<Iterable<E>> {
 /// The [equals] and [hash] methods accepts `null` values,
 /// even if the [isValidKey] returns `false` for `null`.
 /// The [hash] of `null` is `null.hashCode`.
-class ListEquality<E> implements Equality<List<E>> {
+final class ListEquality<E> implements Equality<List<E>> {
   final Equality<E> _elementEquality;
   const ListEquality(
       [Equality<E> elementEquality = const DefaultEquality<Never>()])
@@ -202,7 +202,7 @@ class ListEquality<E> implements Equality<List<E>> {
   bool isValidKey(Object? o) => o is List<E>;
 }
 
-abstract class _UnorderedEquality<E, T extends Iterable<E>>
+abstract final class _UnorderedEquality<E, T extends Iterable<E>>
     implements Equality<T> {
   final Equality<E> _elementEquality;
 
@@ -251,7 +251,8 @@ abstract class _UnorderedEquality<E, T extends Iterable<E>>
 /// Two iterables are considered equal if they have the same number of elements,
 /// and the elements of one set can be paired with the elements
 /// of the other iterable, so that each pair are equal.
-class UnorderedIterableEquality<E> extends _UnorderedEquality<E, Iterable<E>> {
+final class UnorderedIterableEquality<E>
+    extends _UnorderedEquality<E, Iterable<E>> {
   const UnorderedIterableEquality(
       [super.elementEquality = const DefaultEquality<Never>()]);
 
@@ -271,7 +272,7 @@ class UnorderedIterableEquality<E> extends _UnorderedEquality<E, Iterable<E>> {
 /// The [equals] and [hash] methods accepts `null` values,
 /// even if the [isValidKey] returns `false` for `null`.
 /// The [hash] of `null` is `null.hashCode`.
-class SetEquality<E> extends _UnorderedEquality<E, Set<E>> {
+final class SetEquality<E> extends _UnorderedEquality<E, Set<E>> {
   const SetEquality([super.elementEquality = const DefaultEquality<Never>()]);
 
   @override
@@ -282,7 +283,7 @@ class SetEquality<E> extends _UnorderedEquality<E, Set<E>> {
 ///
 /// The class represents a map entry as a single object,
 /// using a combined hashCode and equality of the key and value.
-class _MapEntry {
+final class _MapEntry {
   final MapEquality equality;
   final Object? key;
   final Object? value;
@@ -309,7 +310,7 @@ class _MapEntry {
 /// The [equals] and [hash] methods accepts `null` values,
 /// even if the [isValidKey] returns `false` for `null`.
 /// The [hash] of `null` is `null.hashCode`.
-class MapEquality<K, V> implements Equality<Map<K, V>> {
+final class MapEquality<K, V> implements Equality<Map<K, V>> {
   final Equality<K> _keyEquality;
   final Equality<V> _valueEquality;
   const MapEquality(
@@ -372,7 +373,7 @@ class MapEquality<K, V> implements Equality<Map<K, V>> {
 /// for `equals(e1, e2)` and `equals(e2, e1)`. This can happen if one equality
 /// considers only `e1` a valid key, and not `e2`, but an equality which is
 /// checked later, allows both.
-class MultiEquality<E> implements Equality<E> {
+final class MultiEquality<E> implements Equality<E> {
   final Iterable<Equality<E>> _equalities;
 
   const MultiEquality(Iterable<Equality<E>> equalities)
@@ -418,7 +419,7 @@ class MultiEquality<E> implements Equality<E> {
 ///
 /// A list is only equal to another list, likewise for sets and maps. All other
 /// iterables are compared as iterables only.
-class DeepCollectionEquality implements Equality {
+final class DeepCollectionEquality implements Equality {
   final Equality _base;
   final bool _unordered;
   const DeepCollectionEquality([Equality base = const DefaultEquality<Never>()])
@@ -476,7 +477,7 @@ class DeepCollectionEquality implements Equality {
 /// String equality that's insensitive to differences in ASCII case.
 ///
 /// Non-ASCII characters are compared as-is, with no conversion.
-class CaseInsensitiveEquality implements Equality<String> {
+final class CaseInsensitiveEquality implements Equality<String> {
   const CaseInsensitiveEquality();
 
   @override
diff --git a/pkgs/collection/lib/src/equality_map.dart b/pkgs/collection/lib/src/equality_map.dart
index 542977f69..fb8537d22 100644
--- a/pkgs/collection/lib/src/equality_map.dart
+++ b/pkgs/collection/lib/src/equality_map.dart
@@ -8,7 +8,7 @@ import 'equality.dart';
 import 'wrappers.dart';
 
 /// A [Map] whose key equality is determined by an [Equality] object.
-class EqualityMap<K, V> extends DelegatingMap<K, V> {
+final class EqualityMap<K, V> extends DelegatingMap<K, V> {
   /// Creates a map with equality based on [equality].
   EqualityMap(Equality<K> equality)
       : super(LinkedHashMap(
diff --git a/pkgs/collection/lib/src/equality_set.dart b/pkgs/collection/lib/src/equality_set.dart
index 8edbba5bd..529fc20ad 100644
--- a/pkgs/collection/lib/src/equality_set.dart
+++ b/pkgs/collection/lib/src/equality_set.dart
@@ -8,7 +8,7 @@ import 'equality.dart';
 import 'wrappers.dart';
 
 /// A [Set] whose key equality is determined by an [Equality] object.
-class EqualitySet<E> extends DelegatingSet<E> {
+final class EqualitySet<E> extends DelegatingSet<E> {
   /// Creates a set with equality based on [equality].
   EqualitySet(Equality<E> equality)
       : super(LinkedHashSet(
diff --git a/pkgs/collection/lib/src/functions.dart b/pkgs/collection/lib/src/functions.dart
index db8657417..04121583d 100644
--- a/pkgs/collection/lib/src/functions.dart
+++ b/pkgs/collection/lib/src/functions.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);
 }
diff --git a/pkgs/collection/lib/src/iterable_extensions.dart b/pkgs/collection/lib/src/iterable_extensions.dart
index 10f467608..8056adb6a 100644
--- a/pkgs/collection/lib/src/iterable_extensions.dart
+++ b/pkgs/collection/lib/src/iterable_extensions.dart
@@ -16,7 +16,7 @@ import 'utils.dart';
 ///
 /// More specialized extension methods that only apply to
 /// iterables with specific element types include those of
-/// [IterableComparableExtension] and [IterableNullableExtension].
+/// [IterableComparableExtension].
 extension IterableExtension<T> on Iterable<T> {
   /// Selects [count] elements at random from this iterable.
   ///
@@ -604,6 +604,8 @@ extension IterableExtension<T> on Iterable<T> {
 }
 
 /// Extensions that apply to iterables with a nullable element type.
+/// @nodoc
+@Deprecated('Use .nonNulls instead.')
 extension IterableNullableExtension<T extends Object> on Iterable<T?> {
   /// The non-`null` elements of this `Iterable`.
   ///
@@ -611,6 +613,7 @@ extension IterableNullableExtension<T extends Object> on Iterable<T?> {
   /// of this iterable, in their original iteration order.
   ///
   /// For an `Iterable<X?>`, this method is equivalent to `.whereType<X>()`.
+  /// @nodoc
   @Deprecated('Use .nonNulls instead.')
   Iterable<T> whereNotNull() sync* {
     for (var element in this) {
diff --git a/pkgs/collection/lib/src/iterable_zip.dart b/pkgs/collection/lib/src/iterable_zip.dart
index 9671eaf3f..89a0316c2 100644
--- a/pkgs/collection/lib/src/iterable_zip.dart
+++ b/pkgs/collection/lib/src/iterable_zip.dart
@@ -13,7 +13,9 @@ 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.
-class IterableZip<T> extends IterableBase<List<T>> {
+/// @nodoc
+@Deprecated('Use [i1, i2].zip from dart:collection')
+final class IterableZip<T> extends IterableBase<List<T>> {
   final Iterable<Iterable<T>> _iterables;
 
   IterableZip(Iterable<Iterable<T>> iterables) : _iterables = iterables;
@@ -27,7 +29,7 @@ class IterableZip<T> extends IterableBase<List<T>> {
   }
 }
 
-class _IteratorZip<T> implements Iterator<List<T>> {
+final class _IteratorZip<T> implements Iterator<List<T>> {
   final List<Iterator<T>> _iterators;
   List<T>? _current;
 
diff --git a/pkgs/collection/lib/src/priority_queue.dart b/pkgs/collection/lib/src/priority_queue.dart
index 11b0348a2..41073b1b2 100644
--- a/pkgs/collection/lib/src/priority_queue.dart
+++ b/pkgs/collection/lib/src/priority_queue.dart
@@ -21,7 +21,7 @@ import 'utils.dart';
 /// If elements override [Object.==], the `comparison` function must
 /// always give equal objects the same priority,
 /// otherwise [contains] or [remove] might not work correctly.
-abstract class PriorityQueue<E> {
+abstract interface class PriorityQueue<E> {
   /// Creates an empty [PriorityQueue].
   ///
   /// The created [PriorityQueue] is a plain [HeapPriorityQueue].
@@ -168,7 +168,7 @@ abstract class PriorityQueue<E> {
 ///   and is linear, O(n).
 /// * The [toSet] operation effectively adds each element to the new set, taking
 ///   an expected O(n*log(n)) time.
-class HeapPriorityQueue<E> implements PriorityQueue<E> {
+final class HeapPriorityQueue<E> implements PriorityQueue<E> {
   /// Initial capacity of a queue when created, or when added to after a
   /// [clear].
   ///
diff --git a/pkgs/collection/lib/src/queue_list.dart b/pkgs/collection/lib/src/queue_list.dart
index a3eaba136..9fffa167c 100644
--- a/pkgs/collection/lib/src/queue_list.dart
+++ b/pkgs/collection/lib/src/queue_list.dart
@@ -5,11 +5,7 @@
 import 'dart:collection';
 
 /// A class that efficiently implements both [Queue] and [List].
-// TODO(nweiz): Currently this code is copied almost verbatim from
-// dart:collection. The only changes are to implement List and to remove methods
-// that are redundant with ListMixin. Remove or simplify it when issue 21330 is
-// fixed.
-class QueueList<E> extends Object with ListMixin<E> implements Queue<E> {
+interface class QueueList<E> with ListMixin<E> implements Queue<E> {
   /// Adapts [source] to be a `QueueList<T>`.
   ///
   /// Any time the class would produce an element that is not a [T], the element
@@ -115,9 +111,6 @@ class QueueList<E> extends Object with ListMixin<E> implements Queue<E> {
 
   QueueList<T> cast<T>() => QueueList._castFrom<E, T>(this);
 
-  @Deprecated('Use cast instead')
-  QueueList<T> retype<T>() => cast<T>();
-
   @override
   String toString() => IterableBase.iterableToFullString(this, '{', '}');
 
@@ -274,7 +267,7 @@ class QueueList<E> extends Object with ListMixin<E> implements Queue<E> {
   }
 }
 
-class _CastQueueList<S, T> extends QueueList<T> {
+final class _CastQueueList<S, T> extends QueueList<T> {
   final QueueList<S> _delegate;
 
   // Assigns invalid values for head/tail because it uses the delegate to hold
diff --git a/pkgs/collection/lib/src/union_set.dart b/pkgs/collection/lib/src/union_set.dart
index a34d7ad37..06cde03bf 100644
--- a/pkgs/collection/lib/src/union_set.dart
+++ b/pkgs/collection/lib/src/union_set.dart
@@ -13,7 +13,7 @@ import 'unmodifiable_wrappers.dart';
 /// If an element is in multiple sets and the outer set is ordered, the version
 /// in the earliest inner set is preferred. Component sets are assumed to use
 /// `==` and `hashCode` for equality.
-class UnionSet<E> extends SetBase<E> with UnmodifiableSetMixin<E> {
+final class UnionSet<E> extends SetBase<E> with UnmodifiableSetMixin<E> {
   /// The set of sets that this provides a view of.
   final Set<Set<E>> _sets;
 
diff --git a/pkgs/collection/lib/src/union_set_controller.dart b/pkgs/collection/lib/src/union_set_controller.dart
index 498528e20..3600c525d 100644
--- a/pkgs/collection/lib/src/union_set_controller.dart
+++ b/pkgs/collection/lib/src/union_set_controller.dart
@@ -21,7 +21,7 @@ import 'union_set.dart';
 ///   }
 /// }
 /// ```
-class UnionSetController<E> {
+interface class UnionSetController<E> {
   /// The [UnionSet] that provides a view of the union of sets in `this`.
   final UnionSet<E> set;
 
diff --git a/pkgs/collection/lib/src/unmodifiable_wrappers.dart b/pkgs/collection/lib/src/unmodifiable_wrappers.dart
index a73a55b31..897ccdbc2 100644
--- a/pkgs/collection/lib/src/unmodifiable_wrappers.dart
+++ b/pkgs/collection/lib/src/unmodifiable_wrappers.dart
@@ -193,14 +193,4 @@ abstract mixin class UnmodifiableMapMixin<K, V> implements Map<K, V> {
   /// operations that change the map are disallowed.
   @override
   void clear() => _throw();
-
-  /// Throws an [UnsupportedError].
-  // ignore: provide_deprecation_message
-  @deprecated
-  set first(Object? _) => _throw();
-
-  /// Throws an [UnsupportedError].
-  // ignore: provide_deprecation_message
-  @deprecated
-  set last(Object? _) => _throw();
 }
diff --git a/pkgs/collection/lib/src/wrappers.dart b/pkgs/collection/lib/src/wrappers.dart
index 859d0bcc4..a703e4e65 100644
--- a/pkgs/collection/lib/src/wrappers.dart
+++ b/pkgs/collection/lib/src/wrappers.dart
@@ -79,9 +79,6 @@ abstract class _DelegatingIterableBase<E> implements Iterable<E> {
   @override
   E reduce(E Function(E value, E element) combine) => _base.reduce(combine);
 
-  @Deprecated('Use cast instead')
-  Iterable<T> retype<T>() => cast<T>();
-
   @override
   E get single => _base.single;
 
@@ -129,18 +126,6 @@ class DelegatingIterable<E> extends _DelegatingIterableBase<E> {
 
   /// Creates a wrapper that forwards operations to [base].
   const DelegatingIterable(Iterable<E> base) : _base = base;
-
-  /// Creates a wrapper that asserts the types of values in [base].
-  ///
-  /// This soundly converts an [Iterable] without a generic type to an
-  /// `Iterable<E>` by asserting that its elements are instances of `E` whenever
-  /// they're accessed. If they're not, it throws a [TypeError].
-  ///
-  /// This forwards all operations to [base], so any changes in [base] will be
-  /// reflected in `this`. If [base] is already an `Iterable<E>`, it's returned
-  /// unmodified.
-  @Deprecated('Use iterable.cast<E> instead.')
-  static Iterable<E> typed<E>(Iterable base) => base.cast<E>();
 }
 
 /// A [List] that delegates all operations to a base list.
@@ -154,20 +139,6 @@ class DelegatingList<E> extends _DelegatingIterableBase<E> implements List<E> {
 
   const DelegatingList(List<E> base) : _base = base;
 
-  /// Creates a wrapper that asserts the types of values in [base].
-  ///
-  /// This soundly converts a [List] without a generic type to a `List<E>` by
-  /// asserting that its elements are instances of `E` whenever they're
-  /// accessed. If they're not, it throws a [TypeError]. Note that even if an
-  /// operation throws a [TypeError], it may still mutate the underlying
-  /// collection.
-  ///
-  /// This forwards all operations to [base], so any changes in [base] will be
-  /// reflected in `this`. If [base] is already a `List<E>`, it's returned
-  /// unmodified.
-  @Deprecated('Use list.cast<E> instead.')
-  static List<E> typed<E>(List base) => base.cast<E>();
-
   @override
   E operator [](int index) => _base[index];
 
@@ -278,10 +249,6 @@ class DelegatingList<E> extends _DelegatingIterableBase<E> implements List<E> {
     _base.retainWhere(test);
   }
 
-  @Deprecated('Use cast instead')
-  @override
-  List<T> retype<T>() => cast<T>();
-
   @override
   Iterable<E> get reversed => _base.reversed;
 
@@ -319,20 +286,6 @@ class DelegatingSet<E> extends _DelegatingIterableBase<E> implements Set<E> {
 
   const DelegatingSet(Set<E> base) : _base = base;
 
-  /// Creates a wrapper that asserts the types of values in [base].
-  ///
-  /// This soundly converts a [Set] without a generic type to a `Set<E>` by
-  /// asserting that its elements are instances of `E` whenever they're
-  /// accessed. If they're not, it throws a [TypeError]. Note that even if an
-  /// operation throws a [TypeError], it may still mutate the underlying
-  /// collection.
-  ///
-  /// This forwards all operations to [base], so any changes in [base] will be
-  /// reflected in `this`. If [base] is already a `Set<E>`, it's returned
-  /// unmodified.
-  @Deprecated('Use set.cast<E> instead.')
-  static Set<E> typed<E>(Set base) => base.cast<E>();
-
   @override
   bool add(E value) => _base.add(value);
 
@@ -379,10 +332,6 @@ class DelegatingSet<E> extends _DelegatingIterableBase<E> implements Set<E> {
     _base.retainAll(elements);
   }
 
-  @Deprecated('Use cast instead')
-  @override
-  Set<T> retype<T>() => cast<T>();
-
   @override
   void retainWhere(bool Function(E) test) {
     _base.retainWhere(test);
@@ -407,20 +356,6 @@ class DelegatingQueue<E> extends _DelegatingIterableBase<E>
 
   const DelegatingQueue(Queue<E> queue) : _base = queue;
 
-  /// Creates a wrapper that asserts the types of values in [base].
-  ///
-  /// This soundly converts a [Queue] without a generic type to a `Queue<E>` by
-  /// asserting that its elements are instances of `E` whenever they're
-  /// accessed. If they're not, it throws a [TypeError]. Note that even if an
-  /// operation throws a [TypeError], it may still mutate the underlying
-  /// collection.
-  ///
-  /// This forwards all operations to [base], so any changes in [base] will be
-  /// reflected in `this`. If [base] is already a `Queue<E>`, it's returned
-  /// unmodified.
-  @Deprecated('Use queue.cast<E> instead.')
-  static Queue<E> typed<E>(Queue base) => base.cast<E>();
-
   @override
   void add(E value) {
     _base.add(value);
@@ -462,10 +397,6 @@ class DelegatingQueue<E> extends _DelegatingIterableBase<E>
     _base.retainWhere(test);
   }
 
-  @Deprecated('Use cast instead')
-  @override
-  Queue<T> retype<T>() => cast<T>();
-
   @override
   E removeFirst() => _base.removeFirst();
 
@@ -483,20 +414,6 @@ class DelegatingMap<K, V> implements Map<K, V> {
 
   const DelegatingMap(Map<K, V> base) : _base = base;
 
-  /// Creates a wrapper that asserts the types of keys and values in [base].
-  ///
-  /// This soundly converts a [Map] without generic types to a `Map<K, V>` by
-  /// asserting that its keys are instances of `E` and its values are instances
-  /// of `V` whenever they're accessed. If they're not, it throws a [TypeError].
-  /// Note that even if an operation throws a [TypeError], it may still mutate
-  /// the underlying collection.
-  ///
-  /// This forwards all operations to [base], so any changes in [base] will be
-  /// reflected in `this`. If [base] is already a `Map<K, V>`, it's returned
-  /// unmodified.
-  @Deprecated('Use map.cast<K, V> instead.')
-  static Map<K, V> typed<K, V>(Map base) => base.cast<K, V>();
-
   @override
   V? operator [](Object? key) => _base[key];
 
@@ -563,9 +480,6 @@ class DelegatingMap<K, V> implements Map<K, V> {
   @override
   void removeWhere(bool Function(K, V) test) => _base.removeWhere(test);
 
-  @Deprecated('Use cast instead')
-  Map<K2, V2> retype<K2, V2>() => cast<K2, V2>();
-
   @override
   Iterable<V> get values => _base.values;
 
@@ -589,7 +503,7 @@ class DelegatingMap<K, V> implements Map<K, V> {
 /// getter only shows an [Iterable] view of the keys.
 ///
 /// Note that [lookup] is not supported for this set.
-class MapKeySet<E> extends _DelegatingIterableBase<E>
+final class MapKeySet<E> extends _DelegatingIterableBase<E>
     with UnmodifiableSetMixin<E> {
   final Map<E, dynamic> _baseMap;
 
@@ -651,10 +565,6 @@ class MapKeySet<E> extends _DelegatingIterableBase<E>
   E lookup(Object? element) =>
       throw UnsupportedError("MapKeySet doesn't support lookup().");
 
-  @Deprecated('Use cast instead')
-  @override
-  Set<T> retype<T>() => Set.castFrom<E, T>(this);
-
   /// Returns a new set which contains all the elements of `this` and [other].
   ///
   /// That is, the returned set contains all the elements of this [Set] and all
@@ -687,7 +597,8 @@ class MapKeySet<E> extends _DelegatingIterableBase<E>
 /// `recordSet.add(databaseRecord)` and `recordMap[id]`.
 ///
 /// Effectively, the map will act as a kind of index for the set.
-class MapValueSet<K, V> extends _DelegatingIterableBase<V> implements Set<V> {
+final class MapValueSet<K, V> extends _DelegatingIterableBase<V>
+    implements Set<V> {
   final Map<K, V> _baseMap;
   final K Function(V) _keyForValue;
 
@@ -822,10 +733,6 @@ class MapValueSet<K, V> extends _DelegatingIterableBase<V> implements Set<V> {
   void retainWhere(bool Function(V) test) =>
       removeWhere((element) => !test(element));
 
-  @Deprecated('Use cast instead')
-  @override
-  Set<T> retype<T>() => Set.castFrom<V, T>(this);
-
   /// Returns a new set which contains all the elements of `this` and [other].
   ///
   /// That is, the returned set contains all the elements of this [Set] and all
diff --git a/pkgs/collection/lib/wrappers.dart b/pkgs/collection/lib/wrappers.dart
deleted file mode 100644
index be529ca25..000000000
--- a/pkgs/collection/lib/wrappers.dart
+++ /dev/null
@@ -1,11 +0,0 @@
-// Copyright (c) 2013, 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.
-
-/// Import `collection.dart` instead.
-@Deprecated('Will be removed in collection 2.0.0.')
-library;
-
-export 'src/canonicalized_map.dart';
-export 'src/unmodifiable_wrappers.dart';
-export 'src/wrappers.dart';
diff --git a/pkgs/collection/pubspec.yaml b/pkgs/collection/pubspec.yaml
index 26eb4b936..4a6239cbd 100644
--- a/pkgs/collection/pubspec.yaml
+++ b/pkgs/collection/pubspec.yaml
@@ -1,5 +1,5 @@
 name: collection
-version: 1.20.0-wip
+version: 1.20.0-2.0.0.wip
 description: >-
   Collections and utilities functions and classes related to collections.
 repository: https://github.com/dart-lang/core/tree/main/pkgs/collection
@@ -8,11 +8,15 @@ issue_tracker: https://github.com/dart-lang/core/issues?q=is%3Aissue+is%3Aopen+l
 topics:
   - collections
   - data-structures
+  - equality
 
 environment:
-  sdk: ^3.4.0
+  sdk: ^3.6.0
+
+dependencies:
+  meta: ^1.16.0
 
 dev_dependencies:
   benchmark_harness: ^2.3.1
-  dart_flutter_team_lints: ^3.0.0
-  test: ^1.16.6
+  dart_flutter_team_lints: ^3.3.0
+  test: ^1.16.0
diff --git a/pkgs/collection/test/analysis_options.yaml b/pkgs/collection/test/analysis_options.yaml
index 899b0f33c..2d2950532 100644
--- a/pkgs/collection/test/analysis_options.yaml
+++ b/pkgs/collection/test/analysis_options.yaml
@@ -1,6 +1,6 @@
 include: ../analysis_options.yaml
 
-# Turn off the avoid_dynamic_calls lint for the test/ directory.
+# Turn off common lint violations for the test/ directory.
 analyzer:
   errors:
     avoid_dynamic_calls: ignore
diff --git a/pkgs/collection/test/extensions_test.dart b/pkgs/collection/test/extensions_test.dart
index dd9205977..3d909f1c1 100644
--- a/pkgs/collection/test/extensions_test.dart
+++ b/pkgs/collection/test/extensions_test.dart
@@ -2225,7 +2225,7 @@ Iterable<T> iterable<T>(Iterable<T> values) sync* {
   yield* values;
 }
 
-Never unreachable([dynamic _, dynamic __, dynamic ___]) => fail('Unreachable');
+Never unreachable([Object? _, Object? __, Object? ___]) => fail('Unreachable');
 
 String toString(Object? o) => '$o';
 
diff --git a/pkgs/collection/test/functions_test.dart b/pkgs/collection/test/functions_test.dart
index f60230332..11c2e3772 100644
--- a/pkgs/collection/test/functions_test.dart
+++ b/pkgs/collection/test/functions_test.dart
@@ -8,48 +8,6 @@ import 'package:collection/collection.dart';
 import 'package:test/test.dart';
 
 void main() {
-  group('mapMap()', () {
-    test('with an empty map returns an empty map', () {
-      expect(
-          mapMap({},
-              key: expectAsync2((_, __) {}, count: 0),
-              value: expectAsync2((_, __) {}, count: 0)),
-          isEmpty);
-    });
-
-    test('with no callbacks, returns a copy of the map', () {
-      var map = {'foo': 1, 'bar': 2};
-      var result = mapMap<String, int, String, int>(map);
-      expect(result, equals({'foo': 1, 'bar': 2}));
-
-      // The resulting map should be a copy.
-      result['foo'] = 3;
-      expect(map, equals({'foo': 1, 'bar': 2}));
-    });
-
-    test("maps the map's keys", () {
-      expect(
-          mapMap<String, int, dynamic, int>({'foo': 1, 'bar': 2},
-              key: (dynamic key, dynamic value) => key[value]),
-          equals({'o': 1, 'r': 2}));
-    });
-
-    test("maps the map's values", () {
-      expect(
-          mapMap<String, int, String, dynamic>({'foo': 1, 'bar': 2},
-              value: (dynamic key, dynamic value) => key[value]),
-          equals({'foo': 'o', 'bar': 'r'}));
-    });
-
-    test("maps both the map's keys and values", () {
-      expect(
-          mapMap({'foo': 1, 'bar': 2},
-              key: (dynamic key, dynamic value) => '$key$value',
-              value: (dynamic key, dynamic value) => key[value]),
-          equals({'foo1': 'o', 'bar2': 'r'}));
-    });
-  });
-
   group('mergeMaps()', () {
     test('with empty maps returns an empty map', () {
       expect(
@@ -185,60 +143,6 @@ void main() {
     });
   });
 
-  group('transitiveClosure()', () {
-    test('returns an empty map for an empty graph', () {
-      expect(transitiveClosure({}), isEmpty);
-    });
-
-    test('returns the input when there are no transitive connections', () {
-      expect(
-          transitiveClosure({
-            'foo': ['bar'],
-            'bar': [],
-            'bang': ['qux', 'zap'],
-            'qux': [],
-            'zap': []
-          }),
-          equals({
-            'foo': ['bar'],
-            'bar': [],
-            'bang': ['qux', 'zap'],
-            'qux': [],
-            'zap': []
-          }));
-    });
-
-    test('flattens transitive connections', () {
-      expect(
-          transitiveClosure({
-            'qux': [],
-            'bar': ['baz'],
-            'baz': ['qux'],
-            'foo': ['bar']
-          }),
-          equals({
-            'foo': ['bar', 'baz', 'qux'],
-            'bar': ['baz', 'qux'],
-            'baz': ['qux'],
-            'qux': []
-          }));
-    });
-
-    test('handles loops', () {
-      expect(
-          transitiveClosure({
-            'foo': ['bar'],
-            'bar': ['baz'],
-            'baz': ['foo']
-          }),
-          equals({
-            'foo': ['bar', 'baz', 'foo'],
-            'bar': ['baz', 'foo', 'bar'],
-            'baz': ['foo', 'bar', 'baz']
-          }));
-    });
-  });
-
   group('stronglyConnectedComponents()', () {
     test('returns an empty list for an empty graph', () {
       expect(stronglyConnectedComponents({}), isEmpty);
diff --git a/pkgs/collection/test/iterable_zip_test.dart b/pkgs/collection/test/iterable_zip_test.dart
index 3881c6af6..413c85a81 100644
--- a/pkgs/collection/test/iterable_zip_test.dart
+++ b/pkgs/collection/test/iterable_zip_test.dart
@@ -2,6 +2,8 @@
 // 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.
 
+// ignore_for_file: deprecated_member_use_from_same_package
+
 import 'package:collection/collection.dart';
 import 'package:test/test.dart';