Line data    Source code

       1              : // Copyright 2026 The Authors
       2              : //
       3              : // Licensed under the Apache License, Version 2.0 (the "License");
       4              : // you may not use this file except in compliance with the License.
       5              : // You may obtain a copy of the License at
       6              : //
       7              : //      https://www.apache.org/licenses/LICENSE-2.0
       8              : //
       9              : // Unless required by applicable law or agreed to in writing, software
      10              : // distributed under the License is distributed on an "AS IS" BASIS,
      11              : // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      12              : // See the License for the specific language governing permissions and
      13              : // limitations under the License.
      14              : 
      15              : /// Return true if all items in [a] are also in [b]
      16              : ///
      17              : /// This is different to `ListEquality` in the
      18              : /// [`collection`](https://pub.dev/packages/collection) package
      19              : /// as this function does not require the list elements to be in the
      20              : /// same order.
      21            2 : bool hasTheSameElements<T>(Iterable<T> a, Iterable<T> b) {
      22            6 :   if (a.length != b.length) {
      23              :     return false;
      24              :   }
      25              : 
      26            4 :   var checklist = List<bool>.filled(b.length, false, growable: false);
      27              : 
      28            6 :   for (int i = 0; i < a.length; i++) {
      29              :     var found = false;
      30            6 :     for (var j = 0; j < b.length; j++) {
      31            2 :       if (checklist[j]) continue;
      32              : 
      33            6 :       if (a.elementAt(i) == b.elementAt(j)) {
      34            2 :         checklist[j] = true;
      35              :         found = true;
      36              :         break;
      37              :       }
      38              :     }
      39              :     if (!found) {
      40              :       return false;
      41              :     }
      42              :   }
      43              : 
      44              :   return true;
      45              : }
      46              : 
      47              : /// Return true if [a] is a sublist of [b].
      48              : ///
      49              : /// Does not care if the lists are in the same order.
      50            2 : bool isSubList<T>(List<T> a, List<T> b) {
      51            6 :   if (a.length > b.length) {
      52              :     return false;
      53              :   }
      54              : 
      55            4 :   var checklist = List<bool>.filled(b.length, false, growable: false);
      56              : 
      57            6 :   for (var i = 0; i < a.length; i++) {
      58              :     var found = false;
      59            6 :     for (var j = 0; j < b.length; j++) {
      60            2 :       if (checklist[j]) continue;
      61              : 
      62            6 :       if (a[i] == b[j]) {
      63            2 :         checklist[j] = true;
      64              :         found = true;
      65              :         break;
      66              :       }
      67              :     }
      68              :     if (!found) return false;
      69              :   }
      70              :   return true;
      71              : }