Roll Observatory packages and add a roll script

packages/charted/test.disabled/scale/scale_util_test.dart

+/*
+ * Copyright 2014 Google Inc. All rights reserved.
+ *
+ * Use of this source code is governed by a BSD-style
+ * license that can be found in the LICENSE file or at
+ * https://developers.google.com/open-source/licenses/bsd
+ */
+
+part of charted.test.scale;
+
+testScaleUtil() {
+  group('ScaleUtil::nice()', () {
+    Nice nice = new Nice((num x) => x.ceil(), (num x) => x.floor());
+    test('extends domain extent to nice values '
+        'when domain[0] <= domain[last]', () {
+      expect(ScaleUtil.nice([0, 5], nice), orderedEquals([0, 5]));
+      expect(ScaleUtil.nice([0.5, 4.5], nice), orderedEquals([0, 5]));
+    });
+    test('extends domain extent to nice values '
+        'when domain[0] > domain[last]', () {
+      expect(ScaleUtil.nice([5, 0], nice), orderedEquals([5, 0]));
+      expect(ScaleUtil.nice([4.5, 0.5], nice), orderedEquals([5, 0]));
+    });
+  });
+
+  group('ScaleUtil::niceStep()', () {
+    Nice nice = ScaleUtil.niceStep(5);
+    test('aligns a number to the nearest multiple of step less than num '
+        'when step > 0', () {
+      expect(nice.ceil(4), equals(5));
+      expect(nice.ceil(5), equals(5));
+      expect(nice.ceil(6), equals(10));
+      expect(nice.floor(4), equals(0));
+      expect(nice.floor(5), equals(5));
+      expect(nice.floor(6), equals(5));
+    });
+    Nice nice2 = ScaleUtil.niceStep(0);
+    test('returns the number itself when step <= 0', () {
+      expect(nice2.ceil(4), equals(4));
+      expect(nice2.ceil(5), equals(5));
+      expect(nice2.floor(4), equals(4));
+      expect(nice2.floor(6), equals(6));
+    });
+  });
+
+  test('ScaleUtil::bilinearScale() returns a Function mapping a value '
+      'on domain to corrsponding value on bilinear scale range', () {
+    /* Polylinear scale maps [1, 5] to [2, 10] */
+    Function domain2Range = ScaleUtil.bilinearScale(
+        [1, 5], [2, 10], uninterpolateNumber, interpolateNumber);
+    expect(domain2Range(1), equals(2));
+    expect(domain2Range(5), equals(10));
+    expect(domain2Range(2.5), equals(5));
+    /* Polylinear scale maps [1, 5] to [10, 2] */
+    domain2Range = ScaleUtil.bilinearScale(
+        [1, 5], [10, 2], uninterpolateNumber, interpolateNumber);
+    expect(domain2Range(1), equals(10));
+    expect(domain2Range(5), equals(2));
+    expect(domain2Range(2.5), equals(7));
+  });
+
+  test('ScaleUtil::polylinearScale() returns a Function mapping a value '
+      'on domain to corrsponding value on polylinear scale range', () {
+    /* Polylinear scale maps [1, 7, 9, 15] to [2, 10, 12, 15] */
+    Function domain2Range = ScaleUtil.polylinearScale(
+        [1, 7, 9, 15], [2, 10, 12, 15], uninterpolateNumber, interpolateNumber);
+    /* Values less than 1 use the first segment */
+    expect(domain2Range(-2), equals(-2));
+    /* Values use the first segment */
+    expect(domain2Range(1), equals(2));
+    expect(domain2Range(2.5), equals(4));
+    /* Values use the second segment */
+    expect(domain2Range(7), equals(10));
+    expect(domain2Range(8), equals(11));
+    /* Values use the thrid segment */
+    expect(domain2Range(9), equals(12));
+    expect(domain2Range(12), equals(13.5));
+    expect(domain2Range(15), equals(15));
+    /* Values larger than 15 use the last segment */
+    expect(domain2Range(20), equals(17.5));
+  });
+
+  test('ScaleUtil::bisectLeft() returns the insertion point for x such that'
+      'all left values are smaller than x', () {
+    /* Bisect in the whole segment */
+    expect(ScaleUtil.bisectLeft([0, 1, 2, 3, 4], 1), equals(1));
+    expect(ScaleUtil.bisectLeft([0, 1, 2, 3, 4], 1.5), equals(2));
+    /* Bisect in the segment starting from the third element */
+    expect(ScaleUtil.bisectLeft([0, 1, 2, 3, 4], 1.4, 3), equals(3));
+    /* Bisect in specific segment */
+    expect(ScaleUtil.bisectLeft([0, 1, 2, 3, 4], 1, 3, 4), equals(3));
+    expect(ScaleUtil.bisectLeft([0, 1, 2, 3, 4], 5, 1, 2), equals(2));
+  });
+
+  test('ScaleUtil::bisectRight() returns the insertion point for x such that'
+      'all left values are smaller or equal to x', () {
+    /* Bisect in the whole segment */
+    expect(ScaleUtil.bisectRight([0, 1, 2, 3, 4], 1), equals(2));
+    expect(ScaleUtil.bisectRight([0, 1, 2, 3, 4], 1.5), equals(2));
+    /* Bisect in the segment starting from the third element */
+    expect(ScaleUtil.bisectRight([0, 1, 2, 3, 4], 1, 3), equals(3));
+    /* Bisect in specific segment */
+    expect(ScaleUtil.bisectRight([0, 1, 2, 3, 4], 1, 3, 4), equals(3));
+    expect(ScaleUtil.bisectRight([0, 1, 2, 3, 4], 5, 1, 2), equals(2));
+  });
+
+}