diff --git a/tests/CSSLayoutMeasureModeTest.cpp b/tests/CSSLayoutMeasureModeTest.cpp
new file mode 100644
index 00000000..a05c3bae
--- /dev/null
+++ b/tests/CSSLayoutMeasureModeTest.cpp
@@ -0,0 +1,294 @@
+/**
+ * Copyright (c) 2014-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+#include <CSSLayout/CSSLayout.h>
+#include <gtest/gtest.h>
+
+struct _MeasureConstraint {
+  float width;
+  CSSMeasureMode widthMode;
+  float height;
+  CSSMeasureMode heightMode;
+};
+
+struct _MeasureConstraintList {
+  uint32_t length;
+  struct _MeasureConstraint *constraints;
+};
+
+static CSSSize _measure(void *context,
+                        float width,
+                        CSSMeasureMode widthMode,
+                        float height,
+                        CSSMeasureMode heightMode) {
+  struct _MeasureConstraintList *constraintList = (struct _MeasureConstraintList *)context;
+  struct _MeasureConstraint *constraints = constraintList->constraints;
+  uint32_t currentIndex = constraintList->length;
+  (&constraints[currentIndex])->width = width;
+  (&constraints[currentIndex])->widthMode = widthMode;
+  (&constraints[currentIndex])->height = height;
+  (&constraints[currentIndex])->heightMode = heightMode;
+  constraintList->length = currentIndex + 1;
+
+  return CSSSize {
+      .width = widthMode == CSSMeasureModeUndefined ? 10 : width,
+      .height = heightMode == CSSMeasureModeUndefined ? 10 : width,
+  };
+}
+
+TEST(CSSLayoutTest, exactly_measure_stretched_child_column) {
+  struct _MeasureConstraintList constraintList = _MeasureConstraintList {
+    .length = 0,
+    .constraints = (struct _MeasureConstraint *) malloc(10 * sizeof(struct _MeasureConstraint)),
+  };
+
+  const CSSNodeRef root = CSSNodeNew();
+  CSSNodeStyleSetWidth(root, 100);
+  CSSNodeStyleSetHeight(root, 100);
+
+  const CSSNodeRef root_child0 = CSSNodeNew();
+  CSSNodeSetContext(root_child0, &constraintList);
+  CSSNodeSetMeasureFunc(root_child0, _measure);
+  CSSNodeInsertChild(root, root_child0, 0);
+
+  CSSNodeCalculateLayout(root, CSSUndefined, CSSUndefined, CSSDirectionLTR);
+
+  ASSERT_EQ(1, constraintList.length);
+
+  ASSERT_EQ(100, constraintList.constraints[0].width);
+  ASSERT_EQ(CSSMeasureModeExactly, constraintList.constraints[0].widthMode);
+}
+
+TEST(CSSLayoutTest, exactly_measure_stretched_child_row) {
+  struct _MeasureConstraintList constraintList = _MeasureConstraintList {
+    .length = 0,
+    .constraints = (struct _MeasureConstraint *) malloc(10 * sizeof(struct _MeasureConstraint)),
+  };
+
+  const CSSNodeRef root = CSSNodeNew();
+  CSSNodeStyleSetFlexDirection(root, CSSFlexDirectionRow);
+  CSSNodeStyleSetWidth(root, 100);
+  CSSNodeStyleSetHeight(root, 100);
+
+  const CSSNodeRef root_child0 = CSSNodeNew();
+  CSSNodeSetContext(root_child0, &constraintList);
+  CSSNodeSetMeasureFunc(root_child0, _measure);
+  CSSNodeInsertChild(root, root_child0, 0);
+
+  CSSNodeCalculateLayout(root, CSSUndefined, CSSUndefined, CSSDirectionLTR);
+
+  ASSERT_EQ(1, constraintList.length);
+
+  ASSERT_EQ(100, constraintList.constraints[0].height);
+  ASSERT_EQ(CSSMeasureModeExactly, constraintList.constraints[0].heightMode);
+}
+
+TEST(CSSLayoutTest, at_most_main_axis_column) {
+  struct _MeasureConstraintList constraintList = _MeasureConstraintList {
+    .length = 0,
+    .constraints = (struct _MeasureConstraint *) malloc(10 * sizeof(struct _MeasureConstraint)),
+  };
+
+  const CSSNodeRef root = CSSNodeNew();
+  CSSNodeStyleSetWidth(root, 100);
+  CSSNodeStyleSetHeight(root, 100);
+
+  const CSSNodeRef root_child0 = CSSNodeNew();
+  CSSNodeSetContext(root_child0, &constraintList);
+  CSSNodeSetMeasureFunc(root_child0, _measure);
+  CSSNodeInsertChild(root, root_child0, 0);
+
+  CSSNodeCalculateLayout(root, CSSUndefined, CSSUndefined, CSSDirectionLTR);
+
+  ASSERT_EQ(1, constraintList.length);
+
+  ASSERT_EQ(100, constraintList.constraints[0].height);
+  ASSERT_EQ(CSSMeasureModeAtMost, constraintList.constraints[0].heightMode);
+}
+
+TEST(CSSLayoutTest, at_most_cross_axis_column) {
+  struct _MeasureConstraintList constraintList = _MeasureConstraintList {
+    .length = 0,
+    .constraints = (struct _MeasureConstraint *) malloc(10 * sizeof(struct _MeasureConstraint)),
+  };
+
+  const CSSNodeRef root = CSSNodeNew();
+  CSSNodeStyleSetAlignItems(root, CSSAlignFlexStart);
+  CSSNodeStyleSetWidth(root, 100);
+  CSSNodeStyleSetHeight(root, 100);
+
+  const CSSNodeRef root_child0 = CSSNodeNew();
+  CSSNodeSetContext(root_child0, &constraintList);
+  CSSNodeSetMeasureFunc(root_child0, _measure);
+  CSSNodeInsertChild(root, root_child0, 0);
+
+  CSSNodeCalculateLayout(root, CSSUndefined, CSSUndefined, CSSDirectionLTR);
+
+  ASSERT_EQ(1, constraintList.length);
+
+  ASSERT_EQ(100, constraintList.constraints[0].width);
+  ASSERT_EQ(CSSMeasureModeAtMost, constraintList.constraints[0].widthMode);
+}
+
+TEST(CSSLayoutTest, at_most_main_axis_row) {
+  struct _MeasureConstraintList constraintList = _MeasureConstraintList {
+    .length = 0,
+    .constraints = (struct _MeasureConstraint *) malloc(10 * sizeof(struct _MeasureConstraint)),
+  };
+
+  const CSSNodeRef root = CSSNodeNew();
+  CSSNodeStyleSetFlexDirection(root, CSSFlexDirectionRow);
+  CSSNodeStyleSetWidth(root, 100);
+  CSSNodeStyleSetHeight(root, 100);
+
+  const CSSNodeRef root_child0 = CSSNodeNew();
+  CSSNodeSetContext(root_child0, &constraintList);
+  CSSNodeSetMeasureFunc(root_child0, _measure);
+  CSSNodeInsertChild(root, root_child0, 0);
+
+  CSSNodeCalculateLayout(root, CSSUndefined, CSSUndefined, CSSDirectionLTR);
+
+  ASSERT_EQ(1, constraintList.length);
+
+  ASSERT_EQ(100, constraintList.constraints[0].width);
+  ASSERT_EQ(CSSMeasureModeAtMost, constraintList.constraints[0].widthMode);
+}
+
+TEST(CSSLayoutTest, at_most_cross_axis_row) {
+  struct _MeasureConstraintList constraintList = _MeasureConstraintList {
+    .length = 0,
+    .constraints = (struct _MeasureConstraint *) malloc(10 * sizeof(struct _MeasureConstraint)),
+  };
+
+  const CSSNodeRef root = CSSNodeNew();
+  CSSNodeStyleSetFlexDirection(root, CSSFlexDirectionRow);
+  CSSNodeStyleSetAlignItems(root, CSSAlignFlexStart);
+  CSSNodeStyleSetWidth(root, 100);
+  CSSNodeStyleSetHeight(root, 100);
+
+  const CSSNodeRef root_child0 = CSSNodeNew();
+  CSSNodeSetContext(root_child0, &constraintList);
+  CSSNodeSetMeasureFunc(root_child0, _measure);
+  CSSNodeInsertChild(root, root_child0, 0);
+
+  CSSNodeCalculateLayout(root, CSSUndefined, CSSUndefined, CSSDirectionLTR);
+
+  ASSERT_EQ(1, constraintList.length);
+
+  ASSERT_EQ(100, constraintList.constraints[0].height);
+  ASSERT_EQ(CSSMeasureModeAtMost, constraintList.constraints[0].heightMode);
+}
+
+TEST(CSSLayoutTest, flex_child) {
+  struct _MeasureConstraintList constraintList = _MeasureConstraintList {
+    .length = 0,
+    .constraints = (struct _MeasureConstraint *) malloc(10 * sizeof(struct _MeasureConstraint)),
+  };
+
+  const CSSNodeRef root = CSSNodeNew();
+  CSSNodeStyleSetHeight(root, 100);
+
+  const CSSNodeRef root_child0 = CSSNodeNew();
+  CSSNodeStyleSetFlexGrow(root_child0, 1);
+  CSSNodeSetContext(root_child0, &constraintList);
+  CSSNodeSetMeasureFunc(root_child0, _measure);
+  CSSNodeInsertChild(root, root_child0, 0);
+
+  CSSNodeCalculateLayout(root, CSSUndefined, CSSUndefined, CSSDirectionLTR);
+
+  ASSERT_EQ(2, constraintList.length);
+
+  ASSERT_EQ(100, constraintList.constraints[0].height);
+  ASSERT_EQ(CSSMeasureModeAtMost, constraintList.constraints[0].heightMode);
+
+  ASSERT_EQ(100, constraintList.constraints[1].height);
+  ASSERT_EQ(CSSMeasureModeExactly, constraintList.constraints[1].heightMode);
+}
+
+TEST(CSSLayoutTest, flex_child_with_flex_basis) {
+  struct _MeasureConstraintList constraintList = _MeasureConstraintList {
+    .length = 0,
+    .constraints = (struct _MeasureConstraint *) malloc(10 * sizeof(struct _MeasureConstraint)),
+  };
+
+  const CSSNodeRef root = CSSNodeNew();
+  CSSNodeStyleSetHeight(root, 100);
+
+  const CSSNodeRef root_child0 = CSSNodeNew();
+  CSSNodeStyleSetFlexGrow(root_child0, 1);
+  CSSNodeStyleSetFlexBasis(root_child0, 0);
+  CSSNodeSetContext(root_child0, &constraintList);
+  CSSNodeSetMeasureFunc(root_child0, _measure);
+  CSSNodeInsertChild(root, root_child0, 0);
+
+  CSSNodeCalculateLayout(root, CSSUndefined, CSSUndefined, CSSDirectionLTR);
+
+  ASSERT_EQ(1, constraintList.length);
+
+  ASSERT_EQ(100, constraintList.constraints[0].height);
+  ASSERT_EQ(CSSMeasureModeExactly, constraintList.constraints[0].heightMode);
+}
+
+TEST(CSSLayoutTest, overflow_scroll_column) {
+  struct _MeasureConstraintList constraintList = _MeasureConstraintList {
+    .length = 0,
+    .constraints = (struct _MeasureConstraint *) malloc(10 * sizeof(struct _MeasureConstraint)),
+  };
+
+  const CSSNodeRef root = CSSNodeNew();
+  CSSNodeStyleSetAlignItems(root, CSSAlignFlexStart);
+  CSSNodeStyleSetOverflow(root, CSSOverflowScroll);
+  CSSNodeStyleSetHeight(root, 100);
+  CSSNodeStyleSetWidth(root, 100);
+
+  const CSSNodeRef root_child0 = CSSNodeNew();
+  CSSNodeSetContext(root_child0, &constraintList);
+  CSSNodeSetMeasureFunc(root_child0, _measure);
+  CSSNodeInsertChild(root, root_child0, 0);
+
+  CSSNodeCalculateLayout(root, CSSUndefined, CSSUndefined, CSSDirectionLTR);
+
+  ASSERT_EQ(1, constraintList.length);
+
+  ASSERT_EQ(100, constraintList.constraints[0].width);
+  ASSERT_EQ(CSSMeasureModeAtMost, constraintList.constraints[0].widthMode);
+
+  ASSERT_TRUE(CSSValueIsUndefined(constraintList.constraints[0].height));
+  ASSERT_EQ(CSSMeasureModeUndefined, constraintList.constraints[0].heightMode);
+}
+
+TEST(CSSLayoutTest, overflow_scroll_row) {
+  struct _MeasureConstraintList constraintList = _MeasureConstraintList {
+    .length = 0,
+    .constraints = (struct _MeasureConstraint *) malloc(10 * sizeof(struct _MeasureConstraint)),
+  };
+
+  const CSSNodeRef root = CSSNodeNew();
+  CSSNodeStyleSetAlignItems(root, CSSAlignFlexStart);
+  CSSNodeStyleSetFlexDirection(root, CSSFlexDirectionRow);
+  CSSNodeStyleSetOverflow(root, CSSOverflowScroll);
+  CSSNodeStyleSetHeight(root, 100);
+  CSSNodeStyleSetWidth(root, 100);
+
+  const CSSNodeRef root_child0 = CSSNodeNew();
+  CSSNodeSetContext(root_child0, &constraintList);
+  CSSNodeSetMeasureFunc(root_child0, _measure);
+  CSSNodeInsertChild(root, root_child0, 0);
+
+  CSSNodeCalculateLayout(root, CSSUndefined, CSSUndefined, CSSDirectionLTR);
+
+  ASSERT_EQ(1, constraintList.length);
+
+  ASSERT_TRUE(CSSValueIsUndefined(constraintList.constraints[0].width));
+  ASSERT_EQ(CSSMeasureModeUndefined, constraintList.constraints[0].widthMode);
+
+  ASSERT_EQ(100, constraintList.constraints[0].height);
+  ASSERT_EQ(CSSMeasureModeAtMost, constraintList.constraints[0].heightMode);
+
+}