Index: third_party/WebKit/Source/devtools/front_end/common/SegmentedRange.js |
diff --git a/third_party/WebKit/Source/devtools/front_end/common/SegmentedRange.js b/third_party/WebKit/Source/devtools/front_end/common/SegmentedRange.js |
new file mode 100644 |
index 0000000000000000000000000000000000000000..6505aaa7029f4805775533a46e7db7f0c48dfd5f |
--- /dev/null |
+++ b/third_party/WebKit/Source/devtools/front_end/common/SegmentedRange.js |
@@ -0,0 +1,112 @@ |
+// Copyright 2016 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+/** |
+ * @constructor |
+ * @param {number} begin |
+ * @param {number} end |
+ * @param {*} data |
+ */ |
+WebInspector.Segment = function(begin, end, data) |
+{ |
+ if (begin > end) |
+ console.assert(false, "Invalid segment"); |
+ this.begin = begin; |
+ this.end = end; |
+ this.data = data; |
+} |
+ |
+WebInspector.Segment.prototype = { |
+ /** |
+ * @param {!WebInspector.Segment} that |
+ * @return {boolean} |
+ */ |
+ intersects: function(that) |
+ { |
+ return this.begin < that.end && that.begin < this.end; |
+ } |
+}; |
+ |
+/** |
+ * @constructor |
+ * @param {(function(!WebInspector.Segment, !WebInspector.Segment): ?WebInspector.Segment)=} mergeCallback |
+ */ |
+WebInspector.SegmentedRange = function(mergeCallback) |
+{ |
+ /** @type {!Array<!WebInspector.Segment>} */ |
+ this._segments = []; |
+ this._mergeCallback = mergeCallback; |
+} |
+ |
+WebInspector.SegmentedRange.prototype = { |
+ /** |
+ * @param {!WebInspector.Segment} newSegment |
+ */ |
+ append: function(newSegment) |
+ { |
+ // 1. Find the proper insertion point for new segment |
+ var startIndex = this._segments.lowerBound(newSegment, (a, b) => a.begin - b.begin); |
+ var endIndex = startIndex; |
+ var merged = null; |
+ if (startIndex > 0) { |
+ // 2. Try mering the preceding segment |
+ var precedingSegment = this._segments[startIndex - 1]; |
+ merged = this._tryMerge(precedingSegment, newSegment); |
+ if (merged) { |
+ --startIndex; |
+ newSegment = merged; |
+ } else if (this._segments[startIndex - 1].end >= newSegment.begin) { |
+ // 2a. If merge failed and segments overlap, adjust preceding segment. |
+ // If an old segment entirely contains new one, split it in two. |
+ if (newSegment.end < precedingSegment.end) |
+ this._segments.splice(startIndex, 0, new WebInspector.Segment(newSegment.end, precedingSegment.end, precedingSegment.data)); |
+ precedingSegment.end = newSegment.begin; |
+ } |
+ } |
+ // 3. Consume all segments that are entirely covered by the new one. |
+ while (endIndex < this._segments.length && this._segments[endIndex].end <= newSegment.end) |
+ ++endIndex; |
+ // 4. Merge or adjust the succeeding segment if it overlaps. |
+ if (endIndex < this._segments.length) { |
+ merged = this._tryMerge(newSegment, this._segments[endIndex]); |
+ if (merged) { |
+ endIndex++; |
+ newSegment = merged; |
+ } else if (newSegment.intersects(this._segments[endIndex])) |
+ this._segments[endIndex].begin = newSegment.end; |
+ } |
+ this._segments.splice(startIndex, endIndex - startIndex, newSegment); |
+ }, |
+ |
+ /** |
+ * @param {!WebInspector.SegmentedRange} that |
+ */ |
+ appendRange: function(that) |
+ { |
+ that.segments().forEach(segment => this.append(segment)); |
+ }, |
+ |
+ /** |
+ * @return {!Array<!WebInspector.Segment>} |
+ */ |
+ segments: function() |
+ { |
+ return this._segments; |
+ }, |
+ |
+ /** |
+ * @param {!WebInspector.Segment} first |
+ * @param {!WebInspector.Segment} second |
+ * @return {?WebInspector.Segment} |
+ */ |
+ _tryMerge: function(first, second) |
+ { |
+ var merged = this._mergeCallback && this._mergeCallback(first, second); |
+ if (!merged) |
+ return null; |
+ merged.begin = first.begin; |
+ merged.end = Math.max(first.end, second.end); |
+ return merged; |
+ } |
+} |