Create generic check methods for RangeError causing checks.

sdk/lib/collection/list.dart

 // 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.
 
 part of dart.collection;
 
 /**
  * Abstract implementation of a list.
  *
  * `ListBase` can be used as a base class for implementing the `List` interface.
@@ skipping 307 matching lines @@
       var tmp = this[length];
       this[length] = this[pos];
       this[pos] = tmp;
     }
   }
 
   Map<int, E> asMap() {
     return new ListMapView(this);
   }
 
-  void _rangeCheck(int start, int end) {
-    if (start < 0 || start > this.length) {
-      throw new RangeError.range(start, 0, this.length);
-    }
-    if (end < start || end > this.length) {
-      throw new RangeError.range(end, start, this.length);
-    }
-  }
-
   List<E> sublist(int start, [int end]) {
-    if (end == null) end = this.length;
-    _rangeCheck(start, end);
+    int listLength = this.length;
+    if (end == null) end = listLength;
+    RangeError.checkValidRange(start, end, listLength);
     int length = end - start;
     List<E> result = new List<E>()..length = length;
     for (int i = 0; i < length; i++) {
       result[i] = this[start + i];
     }
     return result;
   }
 
   Iterable<E> getRange(int start, int end) {
-    _rangeCheck(start, end);
+    RangeError.checkValidRange(start, end, this.length);
     return new SubListIterable<E>(this, start, end);
   }
 
   void removeRange(int start, int end) {
-    _rangeCheck(start, end);
+    RangeError.checkValidRange(start, end, this.length);
     int length = end - start;
     setRange(start, this.length - length, this, end);
     this.length -= length;
   }
 
   void fillRange(int start, int end, [E fill]) {
-    _rangeCheck(start, end);
+    RangeError.checkValidRange(start, end, this.length);
     for (int i = start; i < end; i++) {
       this[i] = fill;
     }
   }
 
   void setRange(int start, int end, Iterable<E> iterable, [int skipCount = 0]) {
-    _rangeCheck(start, end);
+    RangeError.checkValidRange(start, end, this.length);
     int length = end - start;
     if (length == 0) return;
-
-    if (skipCount < 0) throw new ArgumentError(skipCount);
+    RangeError.checkNotNegative(skipCount, "skipCount");
 
     List otherList;
     int otherStart;
     // TODO(floitsch): Make this accept more.
     if (iterable is List) {
       otherList = iterable;
       otherStart = skipCount;
     } else {
       otherList = iterable.skip(skipCount).toList(growable: false);
       otherStart = 0;
     }
     if (otherStart + length > otherList.length) {
       throw IterableElementError.tooFew();
     }
     if (otherStart < start) {
       // Copy backwards to ensure correct copy if [from] is this.
       for (int i = length - 1; i >= 0; i--) {
         this[start + i] = otherList[otherStart + i];
       }
     } else {
       for (int i = 0; i < length; i++) {
         this[start + i] = otherList[otherStart + i];
       }
     }
   }
 
   void replaceRange(int start, int end, Iterable<E> newContents) {
-    _rangeCheck(start, end);
+    RangeError.checkValidRange(start, end, this.length);
     if (newContents is! EfficientLength) {
       newContents = newContents.toList();
     }
     int removeLength = end - start;
     int insertLength = newContents.length;
     if (removeLength >= insertLength) {
       int delta = removeLength - insertLength;
       int insertEnd = start + insertLength;
       int newLength = this.length - delta;
       this.setRange(start, insertEnd, newContents);
@@ skipping 44 matching lines @@
     }
     for (int i = startIndex; i >= 0; i--) {
       if (this[i] == element) {
         return i;
       }
     }
     return -1;
   }
 
   void insert(int index, E element) {
-    if (index < 0 || index > length) {
-      throw new RangeError.range(index, 0, length);
-    }
+    RangeError.checkValueInInterval(index, 0, length, "index");
     if (index == this.length) {
       add(element);
       return;
     }
     // We are modifying the length just below the is-check. Without the check
     // Array.copy could throw an exception, leaving the list in a bad state
     // (with a length that has been increased, but without a new element).
     if (index is! int) throw new ArgumentError(index);
     this.length++;
     setRange(index + 1, this.length, this, index);
     this[index] = element;
   }
 
   E removeAt(int index) {
     E result = this[index];
     setRange(index, this.length - 1, this, index + 1);
     length--;
     return result;
   }
 
   void insertAll(int index, Iterable<E> iterable) {
-    if (index < 0 || index > length) {
-      throw new RangeError.range(index, 0, length);
-    }
+    RangeError.checkValueInInterval(index, 0, length, "index");
     if (iterable is EfficientLength) {
       iterable = iterable.toList();
     }
     int insertionLength = iterable.length;
     // There might be errors after the length change, in which case the list
     // will end up being modified but the operation not complete. Unless we
     // always go through a "toList" we can't really avoid that.
     this.length += insertionLength;
     setRange(index + insertionLength, this.length, this, index);
     setAll(index, iterable);
   }
 
   void setAll(int index, Iterable<E> iterable) {
     if (iterable is List) {
       setRange(index, index + iterable.length, iterable);
     } else {
       for (E element in iterable) {
         this[index++] = element;
       }
     }
   }
 
   Iterable<E> get reversed => new ReversedListIterable<E>(this);
 
   String toString() => IterableBase.iterableToFullString(this, '[', ']');
 }