Attempt 3 at a better touch tabstrip. There is still a bunch to do,

chrome/browser/ui/views/tabs/touch_tab_strip_layout_unittest.cc

+// Copyright (c) 2012 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.
+
+#include "chrome/browser/ui/views/tabs/touch_tab_strip_layout.h"
+
+#include <string>
+
+#include "base/string_number_conversions.h"
+#include "base/string_util.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "ui/views/view.h"
+#include "ui/views/view_model.h"
+
+namespace {
+
+struct CommonTestData {
+  const int initial_x;
+  const int width;
+  const int tab_size;
+  const int tab_padding;
+  const int stacked_offset;
+  const int mini_tab_count;
+  const int active_index;
+  const std::string start_bounds;
+  const std::string expected_bounds;
+};
+
+}  // namespace
+
+class TouchTabStripLayoutTest : public testing::Test {
+ public:
+  TouchTabStripLayoutTest() {}
+
+ protected:
+  void Reset(TouchTabStripLayout* layout,
+             int x,
+             int width,
+             int mini_tab_count,
+             int active_index) {
+    layout->Reset(x, width, mini_tab_count, active_index);
+  }
+
+  void CreateLayout(const CommonTestData& data) {
+    if (!data.start_bounds.empty())
+      PrepareChildViewsFromString(data.start_bounds);
+    else
+      PrepareChildViewsFromString(data.expected_bounds);
+    layout_.reset(new TouchTabStripLayout(
+                     gfx::Size(data.tab_size, 10), data.tab_padding,
+                     data.stacked_offset, 4, &view_model_));
+    if (data.start_bounds.empty()) {
+      PrepareChildViewsFromString(data.expected_bounds);
+      layout_->Reset(data.initial_x, data.width, data.mini_tab_count,
+                     data.active_index);
+    } else {
+      ASSERT_NO_FATAL_FAILURE(SetBoundsFromString(data.start_bounds));
+      layout_->Reset(data.initial_x, data.width, data.mini_tab_count,
+                     data.active_index);
+      ASSERT_NO_FATAL_FAILURE(SetBoundsFromString(data.start_bounds));
+    }
+  }
+
+  void AddViewToViewModel(int index) {
+    views::View* child_view = new views::View;
+    view_.AddChildView(child_view);
+    view_model_.Add(child_view, index);
+  }
+
+  void PrepareChildViewsFromString(const std::string& bounds) {
+    std::vector<std::string> positions;
+    Tokenize(bounds, " ", &positions);
+    PrepareChildViews(static_cast<int>(positions.size()));
+  }
+
+  void PrepareChildViews(int count) {
+    view_model_.Clear();
+    view_.RemoveAllChildViews(true);
+    for (int i = 0; i < count; ++i)
+      AddViewToViewModel(i);
+  }
+
+  void SetBoundsFromString(const std::string& bounds) {
+    std::vector<std::string> positions;
+    Tokenize(bounds, " ", &positions);
+    PrepareChildViews(static_cast<int>(positions.size()));
+    for (int i = 0; i < view_model_.view_size(); ++i) {
+      int x = 0;
+      gfx::Rect bounds(view_model_.ideal_bounds(i));
+      ASSERT_TRUE(base::StringToInt(positions[i], &x));
+      bounds.set_x(x);
+      view_model_.set_ideal_bounds(i, bounds);
+    }
+  }
+
+  std::string BoundsString() const {
+    std::string result;
+    for (int i = 0; i < view_model_.view_size(); ++i) {
+      if (!result.empty())
+        result += " ";
+      result += base::IntToString(view_model_.ideal_bounds(i).x());
+    }
+    return result;
+  }
+
+  std::string BoundsString2(int active_index) const {
+    std::string result;
+    for (int i = 0; i < view_model_.view_size(); ++i) {
+      if (!result.empty())
+        result += " ";
+      if (i == active_index)
+        result += "[";
+      result += base::IntToString(view_model_.ideal_bounds(i).x());
+      if (i == active_index)
+        result += "]";
+    }
+    return result;
+  }
+
+  void Validate(int active_index, int max_width) {
+    // Make sure none of the tabs are more than 90 apart
+    // (tab_size(100) + padding (-10)).
+    for (int j = 1; j < view_model_.view_size(); ++j)
+      EXPECT_LE(ideal_x(j) - ideal_x(j - 1), max_width - 100);
+  }
+
+  int ideal_x(int index) const {
+    return view_model_.ideal_bounds(index).x();
+  }
+
+  scoped_ptr<TouchTabStripLayout> layout_;
+  views::ViewModel view_model_;
+
+ private:
+  views::View view_;
+
+  DISALLOW_COPY_AND_ASSIGN(TouchTabStripLayoutTest);
+};
+
+// Random data.
+TEST_F(TouchTabStripLayoutTest, ValidateInitialLayout) {
+  TouchTabStripLayout layout(gfx::Size(100, 10), -10, 2, 4, &view_model_);
+  PrepareChildViews(12);
+
+  for (int i = 120; i < 600; ++i) {
+    for (int j = 0; j < 12; ++j) {
+      Reset(&layout, 0, i, 0, j);
+      Validate(j, i);
+      if (HasNonfatalFailure())
+        return;
+    }
+  }
+}
+
+// Ensure initial layout is correct.
+TEST_F(TouchTabStripLayoutTest, InitialLayout) {
+  struct CommonTestData test_data[] = {
+    { 0, 198, 100, -10, 1, 0, 9, "",
+      "0 0 0 0 0 0 1 2 3 4 94 95 96 97 98 98 98 98" },
+    { 0, 198, 100, -10, 1, 0, 0, "", "0 90 94 95 96 97 98 98 98" },
+    { 0, 300, 100, -10, 1, 0, 0, "",
+      "0 90 180 196 197 198 199 200 200 200 200" },
+    { 0, 300, 100, -10, 1, 0, 10, "", "0 0 0 0 1 2 3 4 20 110 200" },
+    { 0, 300, 100, -10, 1, 0, 1, "", "0 90 180 196 197 198 199 200 200" },
+    { 0, 643, 160, -27, 6, 0, 0, "", "0 133 266 399" },
+    { 0, 300, 100, -10, 1, 0, 7, "", "0 1 2 3 4 20 110 200" },
+    { 0, 300, 100, -10, 1, 0, 6, "", "0 1 2 3 4 20 110 200" },
+    { 0, 300, 100, -10, 1, 0, 4, "", "0 1 2 3 4 94 184 199 200" },
+  };
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_data); ++i) {
+    CreateLayout(test_data[i]);
+    EXPECT_EQ(test_data[i].expected_bounds, BoundsString()) << " at " << i;
+  }
+}
+
+// Assertions around dragging the active tab to the right.
+TEST_F(TouchTabStripLayoutTest, DragActiveTab) {
+  struct TestData {
+    struct CommonTestData common_data;
+    const int delta;
+  } test_data[] = {
+    { { 0, 300, 100, -10, 2, 0, 4, "", "0 90 180 192 194 196 198 200" }, 1000 },
+    { { 0, 120, 100, -10, 2, 0, 3, "", "0 3 10 12 14 16 18 20" }, 13 },
+    { { 0, 200, 100, -10, 2, 0, 0, "", "0 85 92 94 96 98 100 100" }, -5 },
+    { { 0, 300, 100, -10, 2, 0, 4, "", "0 2 4 18 108 196 198 200" }, 100 },
+    { { 0, 300, 100, -10, 2, 0, 5, "", "0 2 4 6 8 21 111 200" }, 1 },
+    { { 0, 120, 100, -10, 2, 0, 3, "", "0 8 10 12 14 16 18 20" }, 95 },
+    { { 0, 300, 100, -10, 2, 0, 5, "", "0 90 180 192 194 196 198 200" }, 1000 },
+    { { 0, 300, 100, -10, 2, 0, 4, "", "0 2 4 7 97 187 198 200" }, 89 },
+    { { 0, 300, 100, -10, 2, 0, 4, "", "0 2 4 6 96 186 198 200" }, 88 },
+    { { 0, 300, 100, -10, 2, 0, 4, "", "0 2 4 8 98 188 198 200" }, 90 },
+    { { 0, 300, 100, -10, 2, 0, 6, "", "0 2 4 6 8 70 160 200" }, 50 },
+  };
+
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_data); ++i) {
+    CreateLayout(test_data[i].common_data);
+    layout_->DragActiveTab(test_data[i].delta);
+    EXPECT_EQ(test_data[i].common_data.expected_bounds,BoundsString()) <<
+        " at " << i;
+  }
+}
+
+// Assertions for dragging from an existing configuration.
+TEST_F(TouchTabStripLayoutTest, DragActiveTabExisting) {
+  struct TestData {
+    struct CommonTestData common_data;
+    const int delta;
+  } test_data[] = {
+    { { 0, 643, 160, -27, 6, 0, 2, "0 84 217 350 483", "0 84 217 350 483" },
+      -11 },
+    { { 0, 685, 160, -27, 6, 0, 3, "0 6 12 18 151 284 417 519 525",
+        "0 6 12 18 150 283 416 519 525" },
+      -1 },
+    { { 0, 120, 100, -10, 2, 0, 3, "0 3 10 12 14 16 18 20",
+        "0 4 10 12 14 16 18 20" },
+      1 },
+  };
+
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_data); ++i) {
+    CreateLayout(test_data[i].common_data);
+    layout_->DragActiveTab(test_data[i].delta);
+    EXPECT_EQ(test_data[i].common_data.expected_bounds, BoundsString()) <<
+        " at " << i;
+  }
+}
+
+// Assertions for AddTab().
+TEST_F(TouchTabStripLayoutTest, AddTab) {
+  struct TestData {
+    CommonTestData common_data;
+    int add_index;
+    bool add_active;
+    bool add_mini;
+  } test_data[] = {
+    { { 4, 200, 100, -10, 2, 1, 2, "0 4 10 100", "0 0 8 10 100"},
+      1, false, true },
+    { { 4, 200, 100, -10, 2, 1, 2, "0 4 10 100", "0 0 8 98 100"},
+      1, true, true },
+    { { 4, 200, 100, -10, 2, 1, 2, "0 4 10 100", "0 0 8 98 100"},
+      0, true, true },
+    { { 0, 200, 100, -10, 2, 0, 2, "0 2 10 100", "0 4 94 98 100"},
+      0, true, true },
+
+    { { 0, 200, 100, -10, 2, 0, 0, "0 90 92 92 94 96 98 100",
+                                   "0 0 0 2 4 6 8 98 100"},
+      7, true, false },
+    { { 0, 200, 100, -10, 2, 0, 7, "0 2 4 6 8 8 10 100",
+                                   "0 0 2 4 6 8 96 98 100"},
+      5, true, false },
+    { { 0, 200, 100, -10, 2, 0, 7, "0 2 4 6 8 8 10 100",
+                                   "0 2 4 6 8 94 96 98 100"},
+      4, true, false },
+    { { 0, 200, 100, -10, 2, 0, 2, "0 2 10 100", "0 2 10 98 100"},
+      2, true, false },
+    { { 0, 200, 100, -10, 2, 0, 2, "0 2 10 100", "0 2 4 10 100"},
+      4, true, false },
+    { { 0, 200, 100, -10, 2, 0, 2, "0 2 10 100", "0 90 96 98 100"},
+      0, true, false },
+  };
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_data); ++i) {
+    CreateLayout(test_data[i].common_data);
+    int add_types = 0;
+    if (test_data[i].add_active)
+      add_types |= TouchTabStripLayout::kAddTypeActive;
+    if (test_data[i].add_mini)
+      add_types |= TouchTabStripLayout::kAddTypeMini;
+    AddViewToViewModel(test_data[i].add_index);
+    layout_->AddTab(test_data[i].add_index, add_types,
+                    test_data[i].common_data.initial_x +
+                    (test_data[i].add_mini ? 4 : 0));
+    EXPECT_EQ(test_data[i].common_data.expected_bounds, BoundsString()) <<
+        " at " << i;
+  }
+}
+
+// Assertions around removing tabs.
+TEST_F(TouchTabStripLayoutTest, RemoveTab) {
+  // TODO: add coverage of removing mini tabs!
+  struct TestData {
+    struct CommonTestData common_data;
+    const int remove_index;
+    const int x_after_remove;
+  } test_data[] = {
+    // Stacked tabs on both sides.
+    { { 0, 200, 100, -10, 2, 0, 4, "0 2 4 6 8 10 80 98 100",
+        "0 2 4 6 10 80 98 100" },
+      4, 0 },
+
+    // Mini-tabs.
+    { { 8, 200, 100, -10, 2, 1, 0, "0 8 94 96 98 100", "0 86 88 90 100" },
+      0, 0 },
+    { { 16, 200, 100, -10, 2, 2, 0, "0 8 16 94 96 98 100", "8 8 86 88 90 100" },
+      0, 8 },
+    { { 16, 200, 100, -10, 2, 2, 0, "0 8 16 94 96 98 100", "0 8 86 88 90 100" },
+      1, 8 },
+
+    // Remove from ideal layout.
+    { { 0, 200, 100, -10, 2, 0, 0, "0 90 94 96 98 100", "0 90 96 98 100" },
+      0, 0 },
+    { { 0, 200, 100, -10, 2, 0, 0, "0 90 94 96 98 100", "0 90 96 98 100" },
+      1, 0 },
+    { { 0, 200, 100, -10, 2, 0, 0, "0 90 94 96 98 100", "0 90 96 98 100" },
+      2, 0 },
+    { { 0, 200, 100, -10, 2, 0, 0, "0 90 94 96 98 100", "0 90 94 98 100" },
+      3, 0 },
+    { { 0, 200, 100, -10, 2, 0, 0, "0 90 94 96 98 100", "0 90 94 96 100" },
+      5, 0 },
+  };
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_data); ++i) {
+    CreateLayout(test_data[i].common_data);
+    int old_x = view_model_.ideal_bounds(test_data[i].remove_index).x();
+    view_model_.Remove(test_data[i].remove_index);
+    layout_->RemoveTab(test_data[i].remove_index, test_data[i].x_after_remove,
+                       old_x);
+    EXPECT_EQ(test_data[i].common_data.expected_bounds, BoundsString()) <<
+        " at " << i;
+  }
+}
+
+// Assertions for SetWidth().
+TEST_F(TouchTabStripLayoutTest, SetWidth) {
+  struct TestData {
+    CommonTestData common_data;
+    int new_width;
+  } test_data[] = {
+    { { 8, 250, 100, -10, 2, 2, 2, "0 4 8 98 148 150", "0 4 8 98 160 250"},
+      350 },
+    { { 8, 250, 100, -10, 2, 2, 2, "0 4 8 98 148 150", "0 4 8 96 98 100"},
+      200 },
+
+    { { 0, 250, 100, -10, 2, 0, 2, "0 40 90 120 150", "0 40 90 98 100"}, 200 },
+    { { 0, 250, 100, -10, 2, 0, 2, "0 2 60 150", "0 2 60 100"}, 200 },
+    { { 0, 250, 100, -10, 2, 0, 2, "0 40 120 150", "0 40 98 100"}, 200 },
+
+    { { 0, 200, 100, -10, 2, 0, 2, "0 2 10 100", "0 2 60 150"}, 250 },
+    { { 0, 200, 100, -10, 2, 0, 2, "0 2 4 10 100", "0 2 20 110 200"}, 300 },
+  };
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_data); ++i) {
+    CreateLayout(test_data[i].common_data);
+    layout_->SetWidth(test_data[i].new_width);
+    EXPECT_EQ(test_data[i].common_data.expected_bounds, BoundsString()) <<
+        " at " << i;
+  }
+}
+
+// Assertions for SetActiveIndex().
+TEST_F(TouchTabStripLayoutTest, SetActiveIndex) {
+  struct TestData {
+    CommonTestData common_data;
+    int new_index;
+  } test_data[] = {
+    { { 0, 250, 100, -10, 2, 0, 2, "0 4 8 98 148 150", "0 90 144 146 148 150"},
+      0 },
+    { { 0, 250, 100, -10, 2, 0, 2, "0 4 8 98 148 150", "0 2 4 58 148 150"}, 4 },
+    { { 0, 250, 100, -10, 2, 0, 2, "0 4 8 98 148 150", "0 2 4 6 60 150"}, 5 },
+    { { 4, 250, 100, -10, 2, 1, 2, "0 4 8 98 148 150", "0 4 94 146 148 150"},
+      0 },
+  };
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_data); ++i) {
+    CreateLayout(test_data[i].common_data);
+    layout_->SetActiveIndex(test_data[i].new_index);
+    EXPECT_EQ(test_data[i].common_data.expected_bounds, BoundsString()) <<
+        " at " << i;
+  }
+}
+
+TEST_F(TouchTabStripLayoutTest, Foo) {
+  TouchTabStripLayout layout(gfx::Size(160, 10), -27, 6, 4, &view_model_);
+  ASSERT_NO_FATAL_FAILURE(SetBoundsFromString("0 6 12 18 126 259 392 525"));
+  Reset(&layout, 0, 685, 0, 5);
+  ASSERT_NO_FATAL_FAILURE(SetBoundsFromString("0 6 12 18 126 259 392 525"));
+  layout.DragActiveTab(11);
+  layout.DragActiveTab(1);
+}