[bugfix] rm duplication process dimension

Summary: Adds the layout context pointer when publishing `Event::LayoutPassStart`.

Reviewed By: SidharthGuglani

Differential Revision: D15754425

fbshipit-source-id: 6295ae1ebec9eab72a79c43bc1cb0e05a6d7ae68

.clang-format

@@ -9,7 +9,7 @@ AlignTrailingComments: false
 AllowAllParametersOfDeclarationOnNextLine: false
 AllowShortBlocksOnASingleLine: false
 AllowShortCaseLabelsOnASingleLine: false
-AllowShortFunctionsOnASingleLine: Empty
+AllowShortFunctionsOnASingleLine: Inline
 AllowShortIfStatementsOnASingleLine: false
 AllowShortLoopsOnASingleLine: true
 AlwaysBreakAfterReturnType: None

BUCK

@@ -9,21 +9,17 @@ GMOCK_OVERRIDE_FLAGS = [
     "-Wno-inconsistent-missing-override",
 ]
 
-COMPILER_FLAGS = LIBRARY_COMPILER_FLAGS + [
-    "-std=c++1y",
-]
-
 TEST_COMPILER_FLAGS = BASE_COMPILER_FLAGS + GMOCK_OVERRIDE_FLAGS + [
-    "-std=c++1y",
     "-DDEBUG",
+    "-DYG_ENABLE_EVENTS",
 ]
 
 yoga_cxx_library(
     name = "yoga",
-    srcs = glob(["yoga/*.cpp"]),
+    srcs = glob(["yoga/**/*.cpp"]),
     header_namespace = "",
-    exported_headers = subdir_glob([("", "yoga/*.h")]),
-    compiler_flags = COMPILER_FLAGS,
+    exported_headers = subdir_glob([("", "yoga/**/*.h")]),
+    compiler_flags = LIBRARY_COMPILER_FLAGS,
     soname = "libyogacore.$(ext)",
     tests = [":YogaTests"],
     visibility = ["PUBLIC"],
@@ -34,9 +30,9 @@ yoga_cxx_library(
 
 yoga_cxx_library(
     name = "yogaForDebug",
-    srcs = glob(["yoga/*.cpp"]),
+    srcs = glob(["yoga/**/*.cpp"]),
     header_namespace = "",
-    exported_headers = subdir_glob([("", "yoga/*.h")]),
+    exported_headers = subdir_glob([("", "yoga/**/*.h")]),
     compiler_flags = TEST_COMPILER_FLAGS,
     soname = "libyogacore.$(ext)",
     tests = [":YogaTests"],
@@ -55,6 +51,7 @@ yoga_cxx_test(
     visibility = ["PUBLIC"],
     deps = [
         ":yogaForDebug",
+        yoga_dep("testutil:testutil"),
         GTEST_TARGET,
     ],
 )

CMakeLists.txt

@@ -13,3 +13,4 @@ file(GLOB yogacore_SRC yoga/*.cpp)
 add_library(yogacore STATIC ${yogacore_SRC})
 
 target_link_libraries(yogacore android log)
+set_target_properties(yogacore PROPERTIES CXX_STANDARD 11)

YogaKit/Source/UIView+Yoga.h

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

YogaKit/Source/YGLayout+Private.h

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

YogaKit/Source/YGLayout.h

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

benchmark/YGBenchmark.c

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

csharp/BUCK

@@ -12,7 +12,7 @@ load(
     "yoga_dep",
 )
 
-COMPILER_FLAGS = BASE_COMPILER_FLAGS + ["-std=c++14"]
+COMPILER_FLAGS = BASE_COMPILER_FLAGS + ["-std=c++11"]
 
 fb_native.csharp_library(
     name = "yogalibnet46",

csharp/Facebook.Yoga/Native.cs

@@ -43,9 +43,6 @@ namespace Facebook.Yoga
         [DllImport(DllName, ExactSpelling = true, CallingConvention = CallingConvention.Cdecl)]
         public static extern void YGConfigFree(IntPtr node);
 
-        [DllImport(DllName, ExactSpelling = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern int YGNodeGetInstanceCount();
-
         [DllImport(DllName, ExactSpelling = true, CallingConvention = CallingConvention.Cdecl)]
         public static extern int YGConfigGetInstanceCount();
 

csharp/Facebook.Yoga/YogaNode.cs

@@ -673,10 +673,5 @@ namespace Facebook.Yoga
             return _children != null ? ((IEnumerable<YogaNode>)_children).GetEnumerator() :
                 System.Linq.Enumerable.Empty<YogaNode>().GetEnumerator();
         }
-
-        public static int GetInstanceCount()
-        {
-            return Native.YGNodeGetInstanceCount();
-        }
     }
 }

csharp/Yoga/YGInterop.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

csharp/Yoga/YGInterop.h

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

csharp/Yoga/dllmain.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

csharp/Yoga/resource.h

@@ -1,3 +1,9 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the LICENSE
+ * file in the root directory of this source tree.
+ */
 //{{NO_DEPENDENCIES}}
 // Microsoft Visual C++ generated include file.
 // Used by Yoga.rc

csharp/Yoga/stdafx.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

csharp/Yoga/stdafx.h

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

csharp/Yoga/targetver.h

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

enums.py

@@ -3,107 +3,57 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
-from __future__ import absolute_import
-from __future__ import division
-from __future__ import print_function
-from __future__ import unicode_literals
+from __future__ import absolute_import, division, print_function, unicode_literals
+
 import os
 
+
 ENUMS = {
-    'Direction': [
-        'Inherit',
-        'LTR',
-        'RTL',
+    "Direction": ["Inherit", "LTR", "RTL"],
+    "Unit": ["Undefined", "Point", "Percent", "Auto"],
+    "FlexDirection": ["Column", "ColumnReverse", "Row", "RowReverse"],
+    "Justify": [
+        "FlexStart",
+        "Center",
+        "FlexEnd",
+        "SpaceBetween",
+        "SpaceAround",
+        "SpaceEvenly",
     ],
-    'Unit': [
-        'Undefined',
-        'Point',
-        'Percent',
-        'Auto',
+    "Overflow": ["Visible", "Hidden", "Scroll"],
+    "Align": [
+        "Auto",
+        "FlexStart",
+        "Center",
+        "FlexEnd",
+        "Stretch",
+        "Baseline",
+        "SpaceBetween",
+        "SpaceAround",
     ],
-    'FlexDirection': [
-        'Column',
-        'ColumnReverse',
-        'Row',
-        'RowReverse',
+    "PositionType": ["Relative", "Absolute"],
+    "Display": ["Flex", "None"],
+    "Wrap": ["NoWrap", "Wrap", "WrapReverse"],
+    "MeasureMode": ["Undefined", "Exactly", "AtMost"],
+    "Dimension": ["Width", "Height"],
+    "Edge": [
+        "Left",
+        "Top",
+        "Right",
+        "Bottom",
+        "Start",
+        "End",
+        "Horizontal",
+        "Vertical",
+        "All",
     ],
-    'Justify': [
-        'FlexStart',
-        'Center',
-        'FlexEnd',
-        'SpaceBetween',
-        'SpaceAround',
-        'SpaceEvenly',
-    ],
-    'Overflow': [
-        'Visible',
-        'Hidden',
-        'Scroll',
-    ],
-    'Align': [
-        'Auto',
-        'FlexStart',
-        'Center',
-        'FlexEnd',
-        'Stretch',
-        'Baseline',
-        'SpaceBetween',
-        'SpaceAround',
-    ],
-    'PositionType': [
-        'Relative',
-        'Absolute',
-    ],
-    'Display': [
-        'Flex',
-        'None',
-    ],
-    'Wrap': [
-        'NoWrap',
-        'Wrap',
-        'WrapReverse',
-    ],
-    'MeasureMode': [
-        'Undefined',
-        'Exactly',
-        'AtMost',
-    ],
-    'Dimension': [
-        'Width',
-        'Height',
-    ],
-    'Edge': [
-        'Left',
-        'Top',
-        'Right',
-        'Bottom',
-        'Start',
-        'End',
-        'Horizontal',
-        'Vertical',
-        'All',
-    ],
-    'NodeType': [
-        'Default',
-        'Text',
-    ],
-    'LogLevel': [
-        'Error',
-        'Warn',
-        'Info',
-        'Debug',
-        'Verbose',
-        'Fatal',
-    ],
-    'ExperimentalFeature': [
+    "NodeType": ["Default", "Text"],
+    "LogLevel": ["Error", "Warn", "Info", "Debug", "Verbose", "Fatal"],
+    "ExperimentalFeature": [
         # Mimic web flex-basis behavior.
-        'WebFlexBasis',
-    ],
-    'PrintOptions': [
-        ('Layout', 1),
-        ('Style', 2),
-        ('Children', 4),
+        "WebFlexBasis"
     ],
+    "PrintOptions": [("Layout", 1), ("Style", 2), ("Children", 4)],
 }
 
 LICENSE = """/**
@@ -115,23 +65,25 @@ LICENSE = """/**
 
 """
 
+
 def to_java_upper(symbol):
     symbol = str(symbol)
-    out = ''
+    out = ""
     for i in range(0, len(symbol)):
         c = symbol[i]
         if str.istitle(c) and i is not 0 and not str.istitle(symbol[i - 1]):
-            out += '_'
+            out += "_"
         out += c.upper()
     return out
 
+
 def to_log_lower(symbol):
     symbol = str(symbol)
-    out = ''
+    out = ""
     for i in range(0, len(symbol)):
         c = symbol[i]
         if str.istitle(c) and i is not 0 and not str.istitle(symbol[i - 1]):
-            out += '-'
+            out += "-"
         out += c.lower()
     return out
 
@@ -139,114 +91,128 @@ def to_log_lower(symbol):
 root = os.path.dirname(os.path.abspath(__file__))
 
 # write out C & Objective-C headers
-with open(root + '/yoga/YGEnums.h', 'w') as f:
+with open(root + "/yoga/YGEnums.h", "w") as f:
     f.write(LICENSE)
-    f.write('#pragma once\n\n')
+    f.write("#pragma once\n\n")
     f.write('#include "YGMacros.h"\n\n')
-    f.write('YG_EXTERN_C_BEGIN\n\n')
+    f.write("YG_EXTERN_C_BEGIN\n\n")
     for name, values in sorted(ENUMS.items()):
-        f.write('#define YG%sCount %s\n' % (name, len(values)))
-        f.write('typedef YG_ENUM_BEGIN(YG%s) {\n' % name)
+        f.write("#define YG%sCount %s\n" % (name, len(values)))
+        f.write("typedef YG_ENUM_BEGIN(YG%s) {\n" % name)
         for value in values:
             if isinstance(value, tuple):
-                f.write('  YG%s%s = %d,\n' % (name, value[0], value[1]))
+                f.write("  YG%s%s = %d,\n" % (name, value[0], value[1]))
             else:
-                f.write('  YG%s%s,\n' % (name, value))
-        f.write('} YG_ENUM_END(YG%s);\n' % name)
-        f.write('WIN_EXPORT const char *YG%sToString(const YG%s value);\n' % (name, name))
-        f.write('\n')
-    f.write('YG_EXTERN_C_END\n')
+                f.write("  YG%s%s,\n" % (name, value))
+        f.write("} YG_ENUM_END(YG%s);\n" % name)
+        f.write(
+            "WIN_EXPORT const char *YG%sToString(const YG%s value);\n" % (name, name)
+        )
+        f.write("\n")
+    f.write("YG_EXTERN_C_END\n")
 
 # write out C body for printing
-with open(root + '/yoga/YGEnums.cpp', 'w') as f:
+with open(root + "/yoga/YGEnums.cpp", "w") as f:
     f.write(LICENSE)
     f.write('#include "YGEnums.h"\n\n')
     for name, values in sorted(ENUMS.items()):
-        f.write('const char *YG%sToString(const YG%s value){\n' % (name, name))
-        f.write('  switch(value){\n')
+        f.write("const char *YG%sToString(const YG%s value){\n" % (name, name))
+        f.write("  switch(value){\n")
         for value in values:
             if isinstance(value, tuple):
-                f.write('    case YG%s%s:\n' % (name, value[0]))
+                f.write("    case YG%s%s:\n" % (name, value[0]))
                 f.write('      return "%s";\n' % to_log_lower(value[0]))
             else:
-                f.write('    case YG%s%s:\n' % (name, value))
+                f.write("    case YG%s%s:\n" % (name, value))
                 f.write('      return "%s";\n' % to_log_lower(value))
-        f.write('  }\n')
+        f.write("  }\n")
         f.write('  return "unknown";\n')
-        f.write('}\n\n')
+        f.write("}\n\n")
 
 # write out java files
 for name, values in sorted(ENUMS.items()):
-    with open(root + '/java/com/facebook/yoga/Yoga%s.java' % name, 'w') as f:
-        f.write(LICENSE.replace('/**', '/*', 1))
-        f.write('package com.facebook.yoga;\n\n')
-        f.write('import com.facebook.proguard.annotations.DoNotStrip;\n\n')
-        f.write('@DoNotStrip\n')
-        f.write('public enum Yoga%s {\n' % name)
+    with open(root + "/java/com/facebook/yoga/Yoga%s.java" % name, "w") as f:
+        f.write(LICENSE.replace("/**", "/*", 1))
+        f.write("package com.facebook.yoga;\n\n")
+        f.write("import com.facebook.proguard.annotations.DoNotStrip;\n\n")
+        f.write("@DoNotStrip\n")
+        f.write("public enum Yoga%s {\n" % name)
         if len(values) > 0:
             for value in values:
                 if isinstance(value, tuple):
-                    f.write('  %s(%d)' % (to_java_upper(value[0]), value[1]))
+                    f.write("  %s(%d)" % (to_java_upper(value[0]), value[1]))
                 else:
-                    f.write('  %s(%d)' % (to_java_upper(value), values.index(value)))
+                    f.write("  %s(%d)" % (to_java_upper(value), values.index(value)))
                 if values.index(value) is len(values) - 1:
-                    f.write(';\n')
+                    f.write(";\n")
                 else:
-                    f.write(',\n')
+                    f.write(",\n")
         else:
-            f.write('__EMPTY(-1);')
-        f.write('\n')
-        f.write('  private int mIntValue;\n')
-        f.write('\n')
-        f.write('  Yoga%s(int intValue) {\n' % name)
-        f.write('    mIntValue = intValue;\n')
-        f.write('  }\n')
-        f.write('\n')
-        f.write('  public int intValue() {\n')
-        f.write('    return mIntValue;\n')
-        f.write('  }\n')
-        f.write('\n')
-        f.write('  public static Yoga%s fromInt(int value) {\n' % name)
-        f.write('    switch (value) {\n')
+            f.write("__EMPTY(-1);")
+        f.write("\n")
+        f.write("  private int mIntValue;\n")
+        f.write("\n")
+        f.write("  Yoga%s(int intValue) {\n" % name)
+        f.write("    mIntValue = intValue;\n")
+        f.write("  }\n")
+        f.write("\n")
+        f.write("  public int intValue() {\n")
+        f.write("    return mIntValue;\n")
+        f.write("  }\n")
+        f.write("\n")
+        f.write("  public static Yoga%s fromInt(int value) {\n" % name)
+        f.write("    switch (value) {\n")
         for value in values:
             if isinstance(value, tuple):
-                f.write('      case %d: return %s;\n' % (value[1], to_java_upper(value[0])))
+                f.write(
+                    "      case %d: return %s;\n" % (value[1], to_java_upper(value[0]))
+                )
             else:
-                f.write('      case %d: return %s;\n' % (values.index(value), to_java_upper(value)))
-        f.write('      default: throw new IllegalArgumentException("Unknown enum value: " + value);\n')
-        f.write('    }\n')
-        f.write('  }\n')
-        f.write('}\n')
+                f.write(
+                    "      case %d: return %s;\n"
+                    % (values.index(value), to_java_upper(value))
+                )
+        f.write(
+            '      default: throw new IllegalArgumentException("Unknown enum value: " + value);\n'
+        )
+        f.write("    }\n")
+        f.write("  }\n")
+        f.write("}\n")
 
 # write out csharp files
 for name, values in sorted(ENUMS.items()):
-    with open(root + '/csharp/Facebook.Yoga/Yoga%s.cs' % name, 'w') as f:
+    with open(root + "/csharp/Facebook.Yoga/Yoga%s.cs" % name, "w") as f:
         f.write(LICENSE)
-        f.write('namespace Facebook.Yoga\n{\n')
+        f.write("namespace Facebook.Yoga\n{\n")
         if isinstance(next(iter(values or []), None), tuple):
-            f.write('    [System.Flags]\n')
-        f.write('    public enum Yoga%s\n    {\n' % name)
+            f.write("    [System.Flags]\n")
+        f.write("    public enum Yoga%s\n    {\n" % name)
         for value in values:
             if isinstance(value, tuple):
-                f.write('        %s = %d,\n' % (value[0], value[1]))
+                f.write("        %s = %d,\n" % (value[0], value[1]))
             else:
-                f.write('        %s,\n' % value)
-        f.write('    }\n')
-        f.write('}\n')
+                f.write("        %s,\n" % value)
+        f.write("    }\n")
+        f.write("}\n")
 
 # write out javascript file
-with open(root + '/javascript/sources/YGEnums.js', 'w') as f:
+with open(root + "/javascript/sources/YGEnums.js", "w") as f:
     f.write(LICENSE)
-    f.write('module.exports = {\n\n')
+    f.write("module.exports = {\n\n")
     for name, values in sorted(ENUMS.items()):
-        f.write('  %s_COUNT: %s,\n' % (to_java_upper(name), len(values)))
+        f.write("  %s_COUNT: %s,\n" % (to_java_upper(name), len(values)))
         base = 0
         for value in values:
             if isinstance(value, tuple):
-                f.write('  %s_%s: %d,\n' % (to_java_upper(name), to_java_upper(value[0]), value[1]))
+                f.write(
+                    "  %s_%s: %d,\n"
+                    % (to_java_upper(name), to_java_upper(value[0]), value[1])
+                )
                 base = value[1] + 1
             else:
-                f.write('  %s_%s: %d,\n' % (to_java_upper(name), to_java_upper(value), base))
+                f.write(
+                    "  %s_%s: %d,\n" % (to_java_upper(name), to_java_upper(value), base)
+                )
                 base += 1
-        f.write('\n')
-    f.write('};\n')
+        f.write("\n")
+    f.write("};\n")

gradle.properties

@@ -9,7 +9,7 @@
 
 org.gradle.jvmargs=-Xmx1536M
 
-VERSION_NAME=1.14.0
+VERSION_NAME=1.14.0-SNAPSHOT
 POM_URL=https://github.com/facebook/yoga
 POM_SCM_URL=https://github.com/facebook/yoga.git
 POM_SCM_CONNECTION=scm:git:https://github.com/facebook/yoga.git

gradlew.bat

@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

java/BUCK

@@ -3,13 +3,18 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
-load("//tools/build_defs/oss:yoga_defs.bzl", "ANDROID", "CXX_LIBRARY_WHITELIST", "FBJNI_JAVA_TARGET", "FBJNI_TARGET", "INFER_ANNOTATIONS_TARGET", "JNI_TARGET", "JSR_305_TARGET", "JUNIT_TARGET", "PROGRUARD_ANNOTATIONS_TARGET", "SOLOADER_TARGET", "yoga_cxx_library", "yoga_dep", "yoga_java_binary", "yoga_java_library", "yoga_java_test")
+load("//tools/build_defs/oss:yoga_defs.bzl", "ANDROID", "CXX_LIBRARY_WHITELIST", "FBJNI_JAVA_TARGET", "FBJNI_TARGET", "INFER_ANNOTATIONS_TARGET", "JNI_TARGET", "JSR_305_TARGET", "JUNIT_TARGET", "PROGRUARD_ANNOTATIONS_TARGET", "SOLOADER_TARGET", "yoga_cxx_lib", "yoga_cxx_library", "yoga_dep", "yoga_java_binary", "yoga_java_library", "yoga_java_test")
+
+CXX_LIBRARY_WHITELIST_FOR_TESTS = CXX_LIBRARY_WHITELIST + [
+    yoga_cxx_lib("testutil:jni"),
+    yoga_cxx_lib("testutil:testutil"),
+]
 
 yoga_cxx_library(
     name = "jni",
     srcs = glob(["jni/*.cpp"]),
-    headers = glob(["jni/*.h"]),
-    header_namespace = "",
+    header_namespace = "yoga/java",
+    exported_headers = glob(["jni/*.h"]),
     allow_jni_merging = True,
     compiler_flags = [
         "-fno-omit-frame-pointer",
@@ -18,7 +23,7 @@ yoga_cxx_library(
         "-Wall",
         "-Werror",
         "-Os",
-        "-std=c++14",
+        "-std=c++11",
     ],
     platforms = ANDROID,
     preprocessor_flags = [
@@ -55,11 +60,12 @@ yoga_java_library(
 yoga_java_test(
     name = "tests",
     srcs = glob(["tests/**/*.java"]),
-    cxx_library_whitelist = CXX_LIBRARY_WHITELIST,
+    cxx_library_whitelist = CXX_LIBRARY_WHITELIST_FOR_TESTS,
     use_cxx_libraries = True,
     visibility = ["PUBLIC"],
     deps = [
         ":java",
+        yoga_dep("testutil:java"),
         JUNIT_TARGET,
     ],
 )

java/com/facebook/yoga/YogaNative.java

@@ -28,7 +28,6 @@ public class YogaNative {
 
 
   // YGNode related
-  static native int jni_YGNodeGetInstanceCount();
   static native long jni_YGNodeNew(boolean useBatchingForLayoutOutputs);
   static native long jni_YGNodeNewWithConfig(long configPointer, boolean useBatchingForLayoutOutputs);
   static native void jni_YGNodeFree(long nativePointer);

java/jni/YGJNI.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE
@@ -75,34 +75,6 @@ const short int LAYOUT_BORDER_START_INDEX = 14;
 
 bool useBatchingForLayoutOutputs;
 
-class PtrJNodeMap {
-  using JNodeArray = JArrayClass<JYogaNode::javaobject>;
-  std::map<YGNodeRef, size_t> ptrsToIdxs_;
-  alias_ref<JNodeArray> javaNodes_;
-
-public:
-  PtrJNodeMap() : ptrsToIdxs_{}, javaNodes_{} {}
-  PtrJNodeMap(
-      alias_ref<JArrayLong> nativePointers,
-      alias_ref<JNodeArray> javaNodes)
-      : javaNodes_{javaNodes} {
-    auto pin = nativePointers->pinCritical();
-    auto ptrs = pin.get();
-    for (size_t i = 0, n = pin.size(); i < n; ++i) {
-      ptrsToIdxs_[(YGNodeRef) ptrs[i]] = i;
-    }
-  }
-
-  local_ref<JYogaNode> ref(YGNodeRef node) {
-    auto idx = ptrsToIdxs_.find(node);
-    if (idx == ptrsToIdxs_.end()) {
-      return local_ref<JYogaNode>{};
-    } else {
-      return javaNodes_->getElement(idx->second);
-    }
-  }
-};
-
 namespace {
 
 union YGNodeContext {
@@ -135,18 +107,14 @@ public:
     node->setContext(context.asVoidPtr);
   }
 
-  bool has(Edge edge) {
-    return (edges_ & edge) == edge;
-  }
+  bool has(Edge edge) { return (edges_ & edge) == edge; }
 
   YGNodeEdges& add(Edge edge) {
     edges_ |= edge;
     return *this;
   }
 
-  int get() {
-    return edges_;
-  }
+  int get() { return edges_; }
 };
 
 struct YogaValue {
@@ -942,10 +910,6 @@ void jni_YGNodeSetStyleInputs(
   YGNodeSetStyleInputs(_jlong2YGNodeRef(nativePointer), result, size);
 }
 
-jint jni_YGNodeGetInstanceCount() {
-  return YGNodeGetInstanceCount();
-}
-
 jlong jni_YGNodeStyleGetMargin(jlong nativePointer, jint edge) {
   YGNodeRef yogaNodeRef = _jlong2YGNodeRef(nativePointer);
   if (!YGNodeEdges{yogaNodeRef}.has(YGNodeEdges::MARGIN)) {
@@ -1109,7 +1073,6 @@ jint JNI_OnLoad(JavaVM* vm, void*) {
             YGMakeCriticalNativeMethod(jni_YGNodeStyleSetMaxHeightPercent),
             YGMakeCriticalNativeMethod(jni_YGNodeStyleGetAspectRatio),
             YGMakeCriticalNativeMethod(jni_YGNodeStyleSetAspectRatio),
-            YGMakeCriticalNativeMethod(jni_YGNodeGetInstanceCount),
             YGMakeCriticalNativeMethod(jni_YGNodePrint),
             YGMakeNativeMethod(jni_YGNodeClone),
             YGMakeNativeMethod(jni_YGNodeSetStyleInputs),

java/jni/YGJTypes.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

java/jni/YGJTypes.h

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE
@@ -6,6 +6,11 @@
  */
 #include <fb/fbjni.h>
 #include <yoga/YGValue.h>
+#include <yoga/Yoga.h>
+#include <map>
+
+using namespace facebook::jni;
+using namespace std;
 
 struct JYogaNode : public facebook::jni::JavaClass<JYogaNode> {
   static constexpr auto kJavaDescriptor = "Lcom/facebook/yoga/YogaNodeJNIBase;";
@@ -28,3 +33,31 @@ struct JYogaLogger : public facebook::jni::JavaClass<JYogaLogger> {
       facebook::jni::alias_ref<JYogaLogLevel>,
       jstring);
 };
+
+class PtrJNodeMap {
+  using JNodeArray = JArrayClass<JYogaNode::javaobject>;
+  std::map<YGNodeRef, size_t> ptrsToIdxs_;
+  alias_ref<JNodeArray> javaNodes_;
+
+public:
+  PtrJNodeMap() : ptrsToIdxs_{}, javaNodes_{} {}
+  PtrJNodeMap(
+      alias_ref<JArrayLong> nativePointers,
+      alias_ref<JNodeArray> javaNodes)
+      : javaNodes_{javaNodes} {
+    auto pin = nativePointers->pinCritical();
+    auto ptrs = pin.get();
+    for (size_t i = 0, n = pin.size(); i < n; ++i) {
+      ptrsToIdxs_[(YGNodeRef) ptrs[i]] = i;
+    }
+  }
+
+  local_ref<JYogaNode> ref(YGNodeRef node) {
+    auto idx = ptrsToIdxs_.find(node);
+    if (idx == ptrsToIdxs_.end()) {
+      return local_ref<JYogaNode>{};
+    } else {
+      return javaNodes_->getElement(idx->second);
+    }
+  }
+};

java/tests/com/facebook/yoga/YogaNodeTest.java

@@ -31,9 +31,9 @@ public class YogaNodeTest {
 
   @Test
   public void testInit() {
-    final int refCount = YogaNative.jni_YGNodeGetInstanceCount();
+    TestUtil.startCountingNodes();
     final YogaNode node = createNode();
-    assertEquals(refCount + 1, YogaNative.jni_YGNodeGetInstanceCount());
+    assertEquals(1, TestUtil.stopCountingNodes());
   }
 
   @Test
@@ -254,7 +254,7 @@ public class YogaNodeTest {
     root_child0_child0_child0.setFlexShrink(1);
     root_child0_child0.addChildAt(root_child0_child0_child0, 0);
     root.calculateLayout(YogaConstants.UNDEFINED, YogaConstants.UNDEFINED);
-    assertFalse(((YogaNodeJNIBase) root).getDoesLegacyStretchFlagAffectsLayout());
+    assertTrue(((YogaNodeJNIBase) root).getDoesLegacyStretchFlagAffectsLayout());
   }
 
   @Test

javascript/sources/Config.cc

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

javascript/sources/Config.hh

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

javascript/sources/Layout.hh

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

javascript/sources/Node.cc

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

javascript/sources/Node.hh

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

javascript/sources/Size.hh

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

javascript/sources/Value.hh

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

javascript/sources/global.cc

@@ -1,13 +0,0 @@
-/**
- * Copyright (c) Facebook, Inc. and its affiliates.
- *
- * This source code is licensed under the MIT license found in the LICENSE
- * file in the root directory of this source tree.
- */
-#include <yoga/Yoga.h>
-
-#include "./global.hh"
-
-unsigned getInstanceCount(void) {
-  return YGNodeGetInstanceCount();
-}

javascript/sources/global.hh

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

javascript/sources/nbind.cc

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

lib/fb/BUCK

@@ -32,7 +32,7 @@ yoga_cxx_library(
         "-Wall",
         "-Werror",
         "-Wno-unused-parameter",
-        "-std=c++14",
+        "-std=c++11",
     ],
     platforms = (ANDROID,),
     visibility = ["PUBLIC"],

tests/CompactValueTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/EventsTest.cpp

@@ -0,0 +1,147 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the LICENSE
+ * file in the root directory of this source tree.
+ */
+#include <gtest/gtest.h>
+#include <yoga/Yoga.h>
+#include <yoga/event/event.h>
+#include <yoga/YGNode.h>
+#include <yoga/testutil/testutil.h>
+
+#include <algorithm>
+#include <functional>
+#include <memory>
+#include <vector>
+
+namespace facebook {
+namespace yoga {
+namespace test {
+
+struct EventArgs {
+  const YGNode* node;
+  Event::Type type;
+  std::unique_ptr<void, std::function<void(void*)>> dataPtr;
+
+  template <Event::Type E>
+  const Event::TypedData<E>& data() {
+    return *static_cast<Event::TypedData<E>*>(dataPtr.get());
+  }
+};
+
+class EventTest : public ::testing::Test {
+  ScopedEventSubscription subscription = {&EventTest::listen};
+  static void listen(const YGNode&, Event::Type, Event::Data);
+
+public:
+  static std::vector<EventArgs> events;
+  static EventArgs& lastEvent() { return events.back(); }
+  void TearDown() override;
+};
+
+TEST_F(EventTest, new_node_has_event) {
+  auto c = YGConfigGetDefault();
+  auto n = YGNodeNew();
+
+  ASSERT_EQ(lastEvent().node, n);
+  ASSERT_EQ(lastEvent().type, Event::NodeAllocation);
+  ASSERT_EQ(lastEvent().data<Event::NodeAllocation>().config, c);
+
+  YGNodeFree(n);
+}
+
+TEST_F(EventTest, new_node_with_config_event) {
+  auto c = YGConfigNew();
+  auto n = YGNodeNewWithConfig(c);
+
+  ASSERT_EQ(lastEvent().node, n);
+  ASSERT_EQ(lastEvent().type, Event::NodeAllocation);
+  ASSERT_EQ(lastEvent().data<Event::NodeAllocation>().config, c);
+
+  YGNodeFree(n);
+  YGConfigFree(c);
+}
+
+TEST_F(EventTest, clone_node_event) {
+  auto c = YGConfigNew();
+  auto n = YGNodeNewWithConfig(c);
+  auto clone = YGNodeClone(n);
+
+  ASSERT_EQ(lastEvent().node, clone);
+  ASSERT_EQ(lastEvent().type, Event::NodeAllocation);
+  ASSERT_EQ(lastEvent().data<Event::NodeAllocation>().config, c);
+
+  YGNodeFree(n);
+  YGNodeFree(clone);
+  YGConfigFree(c);
+}
+
+TEST_F(EventTest, free_node_event) {
+  auto c = YGConfigNew();
+  auto n = YGNodeNewWithConfig(c);
+  YGNodeFree(n);
+
+  ASSERT_EQ(lastEvent().node, n);
+  ASSERT_EQ(lastEvent().type, Event::NodeDeallocation);
+  ASSERT_EQ(lastEvent().data<Event::NodeDeallocation>().config, c);
+
+  YGConfigFree(c);
+}
+
+TEST_F(EventTest, layout_events) {
+  auto root = YGNodeNew();
+  auto child = YGNodeNew();
+  YGNodeInsertChild(root, child, 0);
+
+  YGNodeCalculateLayout(root, 123, 456, YGDirectionLTR);
+
+  ASSERT_EQ(events[2].node, root);
+  ASSERT_EQ(events[2].type, Event::NodeLayout);
+
+  ASSERT_EQ(events[3].node, child);
+  ASSERT_EQ(events[3].type, Event::NodeLayout);
+
+  YGNodeFreeRecursive(root);
+}
+
+namespace {
+
+template <Event::Type E>
+EventArgs createArgs(const YGNode& node, const Event::Data& data) {
+  using Data = Event::TypedData<E>;
+  auto deleteData = [](void* x) { delete static_cast<Data*>(x); };
+  return {&node, E, {new Data{data.get<E>()}, deleteData}};
+}
+
+} // namespace
+
+void EventTest::listen(const YGNode& node, Event::Type type, Event::Data data) {
+  switch (type) {
+    case Event::NodeAllocation:
+      events.push_back(createArgs<Event::NodeAllocation>(node, data));
+      break;
+    case Event::NodeDeallocation:
+      events.push_back(createArgs<Event::NodeDeallocation>(node, data));
+      break;
+    case Event::NodeLayout:
+      events.push_back(createArgs<Event::NodeLayout>(node, data));
+      break;
+    case Event::LayoutPassStart:
+      break;
+    case Event::LayoutPassEnd:
+      break;
+    case Event::NodeMeasure:
+      break;
+  }
+}
+
+void EventTest::TearDown() {
+  events.clear();
+}
+
+std::vector<EventArgs> EventTest::events{};
+
+} // namespace test
+} // namespace yoga
+} // namespace facebook

tests/InstrumentationTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGAbsolutePositionTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGAlignBaselineTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGAlignContentTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGAlignItemsTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGAlignSelfTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGAndroidNewsFeed.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGAspectRatioTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGBaselineFuncTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGBorderTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGComputedMarginTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGComputedPaddingTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGConfigTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE
@@ -20,12 +20,8 @@ struct ConfigCloningTest : public ::testing::Test {
   void TearDown() override;
 
   static YGNode clonedNode;
-  static YGNodeRef cloneNode(YGNodeRef, YGNodeRef, int) {
-    return &clonedNode;
-  }
-  static YGNodeRef doNotClone(YGNodeRef, YGNodeRef, int) {
-    return nullptr;
-  }
+  static YGNodeRef cloneNode(YGNodeRef, YGNodeRef, int) { return &clonedNode; }
+  static YGNodeRef doNotClone(YGNodeRef, YGNodeRef, int) { return nullptr; }
 };
 
 TEST_F(ConfigCloningTest, uses_values_provided_by_cloning_callback) {

tests/YGDefaultValuesTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGDimensionTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGDirtiedTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGDirtyMarkingTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGDisplayTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGEdgeTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGFlexDirectionTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGFlexTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGFlexWrapTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGFloatOptionalTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGHadOverflowTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGInfiniteHeightTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGJustifyContentTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGLayoutDiffingTest.cpp

@@ -1,14 +1,19 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE
  * file in the root directory of this source tree.
  */
 #include <gtest/gtest.h>
+#include <yoga/testutil/testutil.h>
 #include <yoga/YGNode.h>
 #include <yoga/Yoga.h>
 
+using facebook::yoga::test::TestUtil;
+
 TEST(YogaTest, assert_layout_trees_are_same) {
+  TestUtil::startCountingNodes();
+
   YGConfig* config = YGConfigNew();
   YGConfigSetUseLegacyStretchBehaviour(config, true);
   const YGNodeRef root1 = YGNodeNewWithConfig(config);
@@ -30,12 +35,12 @@ TEST(YogaTest, assert_layout_trees_are_same) {
   YGNodeInsertChild(root1_child0_child0, root1_child0_child0_child0, 0);
 
   const int32_t cal1_configInstanceCount = YGConfigGetInstanceCount();
-  const int32_t cal1_nodeInstanceCount = YGNodeGetInstanceCount();
+  const int32_t cal1_nodeInstanceCount = TestUtil::nodeCount();
 
   YGNodeCalculateLayout(root1, YGUndefined, YGUndefined, YGDirectionLTR);
 
   ASSERT_EQ(YGConfigGetInstanceCount(), cal1_configInstanceCount);
-  ASSERT_EQ(YGNodeGetInstanceCount(), cal1_nodeInstanceCount);
+  ASSERT_EQ(TestUtil::nodeCount(), cal1_nodeInstanceCount);
 
   const YGNodeRef root2 = YGNodeNewWithConfig(config);
   YGNodeStyleSetWidth(root2, 500);
@@ -56,12 +61,12 @@ TEST(YogaTest, assert_layout_trees_are_same) {
   YGNodeInsertChild(root2_child0_child0, root2_child0_child0_child0, 0);
 
   const int32_t cal2_configInstanceCount = YGConfigGetInstanceCount();
-  const int32_t cal2_nodeInstanceCount = YGNodeGetInstanceCount();
+  const int32_t cal2_nodeInstanceCount = TestUtil::nodeCount();
 
   YGNodeCalculateLayout(root2, YGUndefined, YGUndefined, YGDirectionLTR);
 
   ASSERT_EQ(YGConfigGetInstanceCount(), cal2_configInstanceCount);
-  ASSERT_EQ(YGNodeGetInstanceCount(), cal2_nodeInstanceCount);
+  ASSERT_EQ(TestUtil::nodeCount(), cal2_nodeInstanceCount);
 
   ASSERT_TRUE(YGNodeLayoutGetDidUseLegacyFlag(root1));
   ASSERT_TRUE(YGNodeLayoutGetDidUseLegacyFlag(root2));
@@ -70,12 +75,12 @@ TEST(YogaTest, assert_layout_trees_are_same) {
   YGNodeStyleSetAlignItems(root2, YGAlignFlexEnd);
 
   const int32_t cal3_configInstanceCount = YGConfigGetInstanceCount();
-  const int32_t cal3_nodeInstanceCount = YGNodeGetInstanceCount();
+  const int32_t cal3_nodeInstanceCount = TestUtil::nodeCount();
 
   YGNodeCalculateLayout(root2, YGUndefined, YGUndefined, YGDirectionLTR);
 
   ASSERT_EQ(YGConfigGetInstanceCount(), cal3_configInstanceCount);
-  ASSERT_EQ(YGNodeGetInstanceCount(), cal3_nodeInstanceCount);
+  ASSERT_EQ(TestUtil::stopCountingNodes(), cal3_nodeInstanceCount);
 
   ASSERT_FALSE(root1->isLayoutTreeEqualToNode(*root2));
 

tests/YGLoggerTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGMarginTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGMeasureCacheTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGMeasureModeTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGMeasureTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGMinMaxDimensionTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGNodeCallbackTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGNodeChildTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGPaddingTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGPercentageTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGPersistenceTest.cpp

@@ -1,13 +1,16 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE
  * file in the root directory of this source tree.
  */
 #include <gtest/gtest.h>
+#include <yoga/testutil/testutil.h>
 #include <yoga/Yoga.h>
 #include <yoga/YGNode.h>
 
+using facebook::yoga::test::TestUtil;
+
 TEST(YogaTest, cloning_shared_root) {
   const YGConfigRef config = YGConfigNew();
 
@@ -220,7 +223,7 @@ TEST(YogaTest, cloning_two_levels) {
 }
 
 TEST(YogaTest, cloning_and_freeing) {
-  const int32_t initialInstanceCount = YGNodeGetInstanceCount();
+  TestUtil::startCountingNodes();
 
   const YGConfigRef config = YGConfigNew();
 
@@ -249,7 +252,7 @@ TEST(YogaTest, cloning_and_freeing) {
 
   YGConfigFree(config);
 
-  ASSERT_EQ(initialInstanceCount, YGNodeGetInstanceCount());
+  ASSERT_EQ(0, TestUtil::stopCountingNodes());
 }
 
 TEST(YogaTest, mixed_shared_and_owned_children) {

tests/YGRelayoutTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGRoundingFunctionTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGRoundingMeasureFuncTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGRoundingTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGSizeOverflowTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGStyleAccessorsTest.cpp

@@ -0,0 +1,391 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the LICENSE
+ * file in the root directory of this source tree.
+ */
+#include <cstdint>
+#include <type_traits>
+#include <gtest/gtest.h>
+#include <yoga/YGEnums.h>
+#include <yoga/YGStyle.h>
+#include <yoga/YGValue.h>
+
+#include <utility>
+
+using AssignedProps =
+    std::remove_reference<decltype(YGStyle{}.assignedProps())>::type;
+
+namespace {
+constexpr AssignedProps setBits(int from, int n) {
+  return n > 0 ? (setBits(from, n - 1) | AssignedProps{1ull << (from + n - 1)})
+               : 0;
+}
+} // namespace
+
+#define ACCESSOR_TESTS_1(NAME, X) \
+  style.NAME() = X;               \
+  ASSERT_EQ(style.NAME(), X);     \
+  ASSERT_EQ(style.assignedProps(), AssignedProps{1ull << YGStyle::NAME##Bit});
+#define ACCESSOR_TESTS_2(NAME, X, ...) \
+  ACCESSOR_TESTS_1(NAME, X);           \
+  ACCESSOR_TESTS_1(NAME, __VA_ARGS__);
+#define ACCESSOR_TESTS_3(NAME, X, ...) \
+  ACCESSOR_TESTS_1(NAME, X);           \
+  ACCESSOR_TESTS_2(NAME, __VA_ARGS__);
+#define ACCESSOR_TESTS_4(NAME, X, ...) \
+  ACCESSOR_TESTS_1(NAME, X);           \
+  ACCESSOR_TESTS_3(NAME, __VA_ARGS__);
+#define ACCESSOR_TESTS_5(NAME, X, ...) \
+  ACCESSOR_TESTS_1(NAME, X);           \
+  ACCESSOR_TESTS_4(NAME, __VA_ARGS__)
+
+#define ACCESSOR_TESTS_N(a, b, c, d, e, COUNT, ...) ACCESSOR_TESTS_##COUNT
+#define ACCESSOR_TESTS(...) ACCESSOR_TESTS_N(__VA_ARGS__, 5, 4, 3, 2, 1)
+
+#define INDEX_ACCESSOR_TESTS_1(NAME, IDX, X)                           \
+  {                                                                    \
+    auto style = YGStyle{};                                            \
+    style.NAME()[IDX] = X;                                             \
+    ASSERT_EQ(style.NAME()[IDX], X);                                   \
+    ASSERT_EQ(                                                         \
+        style.assignedProps(),                                         \
+        AssignedProps{1ull << (YGStyle::NAME##Bit + IDX)});            \
+    auto asArray = decltype(std::declval<const YGStyle&>().NAME()){X}; \
+    style.NAME() = asArray;                                            \
+    ASSERT_EQ(static_cast<decltype(asArray)>(style.NAME()), asArray);  \
+    ASSERT_EQ(                                                         \
+        style.assignedProps(),                                         \
+        AssignedProps{setBits(                                         \
+            YGStyle::NAME##Bit,                                        \
+            facebook::yoga::enums::count<decltype(IDX)>())});          \
+  }
+
+#define INDEX_ACCESSOR_TESTS_2(NAME, IDX, X, Y) \
+  INDEX_ACCESSOR_TESTS_1(NAME, IDX, X)          \
+  INDEX_ACCESSOR_TESTS_1(NAME, IDX, Y)
+
+#define INDEX_ACCESSOR_TESTS_3(NAME, IDX, X, ...) \
+  INDEX_ACCESSOR_TESTS_1(NAME, IDX, X)            \
+  INDEX_ACCESSOR_TESTS_2(NAME, IDX, __VA_ARGS__)
+
+#define INDEX_ACCESSOR_TESTS_4(NAME, IDX, X, ...) \
+  INDEX_ACCESSOR_TESTS_1(NAME, IDX, X)            \
+  INDEX_ACCESSOR_TESTS_3(NAME, IDX, __VA_ARGS__)
+
+#define INDEX_ACCESSOR_TESTS_5(NAME, IDX, X, ...) \
+  INDEX_ACCESSOR_TESTS_1(NAME, IDX, X)            \
+  INDEX_ACCESSOR_TESTS_4(NAME, IDX, __VA_ARGS__)
+
+#define INDEX_ACCESSOR_TESTS_N(a, b, c, d, e, COUNT, ...) \
+  INDEX_ACCESSOR_TESTS_##COUNT
+#define INDEX_ACCESSOR_TESTS(...) \
+  INDEX_ACCESSOR_TESTS_N(__VA_ARGS__, 5, 4, 3, 2, 1)
+
+// test macro for up to 5 values. If more are needed, extend the macros above.
+#define ACCESSOR_TEST(NAME, DEFAULT_VAL, ...)      \
+  TEST(YGStyle, style_##NAME##_access) {           \
+    auto style = YGStyle{};                        \
+    ASSERT_EQ(style.NAME(), DEFAULT_VAL);          \
+    ACCESSOR_TESTS(__VA_ARGS__)(NAME, __VA_ARGS__) \
+  }
+
+#define INDEX_ACCESSOR_TEST(NAME, DEFAULT_VAL, IDX, ...)      \
+  TEST(YGStyle, style_##NAME##_access) {                      \
+    ASSERT_EQ(YGStyle{}.NAME()[IDX], DEFAULT_VAL);            \
+    ASSERT_EQ(YGStyle{}.assignedProps(), 0);                  \
+    INDEX_ACCESSOR_TESTS(__VA_ARGS__)(NAME, IDX, __VA_ARGS__) \
+  }
+
+namespace facebook {
+namespace yoga {
+
+using CompactValue = detail::CompactValue;
+
+ACCESSOR_TEST(
+    direction,
+    YGDirectionInherit,
+    YGDirectionLTR,
+    YGDirectionRTL,
+    YGDirectionInherit);
+
+ACCESSOR_TEST(
+    flexDirection,
+    YGFlexDirectionColumn,
+    YGFlexDirectionColumnReverse,
+    YGFlexDirectionRowReverse,
+    YGFlexDirectionRow)
+
+ACCESSOR_TEST(
+    justifyContent,
+    YGJustifyFlexStart,
+    YGJustifyFlexEnd,
+    YGJustifySpaceAround,
+    YGJustifyFlexStart,
+    YGJustifySpaceEvenly)
+
+ACCESSOR_TEST(
+    alignContent,
+    YGAlignFlexStart,
+    YGAlignAuto,
+    YGAlignFlexStart,
+    YGAlignCenter,
+    YGAlignFlexEnd,
+    YGAlignStretch)
+
+ACCESSOR_TEST(
+    alignItems,
+    YGAlignStretch,
+    YGAlignFlexStart,
+    YGAlignFlexEnd,
+    YGAlignBaseline,
+    YGAlignSpaceBetween,
+    YGAlignSpaceAround)
+
+ACCESSOR_TEST(
+    alignSelf,
+    YGAlignAuto,
+    YGAlignFlexStart,
+    YGAlignCenter,
+    YGAlignAuto,
+    YGAlignFlexEnd,
+    YGAlignStretch)
+
+ACCESSOR_TEST(
+    positionType,
+    YGPositionTypeRelative,
+    YGPositionTypeAbsolute,
+    YGPositionTypeRelative)
+
+ACCESSOR_TEST(
+    flexWrap,
+    YGWrapNoWrap,
+    YGWrapWrap,
+    YGWrapWrapReverse,
+    YGWrapNoWrap)
+
+ACCESSOR_TEST(
+    overflow,
+    YGOverflowVisible,
+    YGOverflowHidden,
+    YGOverflowScroll,
+    YGOverflowVisible)
+
+ACCESSOR_TEST(display, YGDisplayFlex, YGDisplayNone, YGDisplayFlex)
+
+ACCESSOR_TEST(
+    flex,
+    YGFloatOptional{},
+    YGFloatOptional{123.45f},
+    YGFloatOptional{-9.87f},
+    YGFloatOptional{})
+
+ACCESSOR_TEST(
+    flexGrow,
+    YGFloatOptional{},
+    YGFloatOptional{123.45f},
+    YGFloatOptional{-9.87f},
+    YGFloatOptional{})
+
+ACCESSOR_TEST(
+    flexShrink,
+    YGFloatOptional{},
+    YGFloatOptional{123.45f},
+    YGFloatOptional{-9.87f},
+    YGFloatOptional{})
+
+ACCESSOR_TEST(
+    flexBasis,
+    CompactValue::ofAuto(),
+    CompactValue::ofUndefined(),
+    CompactValue::ofAuto(),
+    CompactValue::of<YGUnitPoint>(7777.77f),
+    CompactValue::of<YGUnitPercent>(-100.0f))
+
+INDEX_ACCESSOR_TEST(
+    position,
+    CompactValue::ofUndefined(),
+    YGEdgeBottom,
+    CompactValue::ofAuto(),
+    CompactValue::ofUndefined(),
+    CompactValue::of<YGUnitPoint>(7777.77f),
+    CompactValue::of<YGUnitPercent>(-100.0f))
+
+INDEX_ACCESSOR_TEST(
+    margin,
+    CompactValue::ofUndefined(),
+    YGEdgeTop,
+    CompactValue::ofAuto(),
+    CompactValue::ofUndefined(),
+    CompactValue::of<YGUnitPoint>(7777.77f),
+    CompactValue::of<YGUnitPercent>(-100.0f))
+
+INDEX_ACCESSOR_TEST(
+    padding,
+    CompactValue::ofUndefined(),
+    YGEdgeAll,
+    CompactValue::of<YGUnitPoint>(7777.77f),
+    CompactValue::ofUndefined(),
+    CompactValue::of<YGUnitPercent>(-100.0f))
+
+INDEX_ACCESSOR_TEST(
+    border,
+    CompactValue::ofUndefined(),
+    YGEdgeHorizontal,
+    CompactValue::of<YGUnitPoint>(-7777.77f),
+    CompactValue::ofUndefined())
+
+INDEX_ACCESSOR_TEST(
+    dimensions,
+    CompactValue::ofAuto(),
+    YGDimensionWidth,
+    CompactValue::ofUndefined(),
+    CompactValue::ofAuto(),
+    CompactValue::of<YGUnitPoint>(7777.77f),
+    CompactValue::of<YGUnitPercent>(-100.0f))
+
+INDEX_ACCESSOR_TEST(
+    minDimensions,
+    CompactValue::ofUndefined(),
+    YGDimensionHeight,
+    CompactValue::ofAuto(),
+    CompactValue::ofUndefined(),
+    CompactValue::of<YGUnitPoint>(7777.77f),
+    CompactValue::of<YGUnitPercent>(-100.0f))
+
+INDEX_ACCESSOR_TEST(
+    maxDimensions,
+    CompactValue::ofUndefined(),
+    YGDimensionHeight,
+    CompactValue::ofAuto(),
+    CompactValue::ofUndefined(),
+    CompactValue::of<YGUnitPoint>(7777.77f),
+    CompactValue::of<YGUnitPercent>(-100.0f))
+
+ACCESSOR_TEST(
+    aspectRatio,
+    YGFloatOptional{},
+    YGFloatOptional{-123.45f},
+    YGFloatOptional{9876.5f},
+    YGFloatOptional{0.0f},
+    YGFloatOptional{});
+
+TEST(YGStyle, set_properties_default_to_0) {
+  ASSERT_EQ(YGStyle{}.assignedProps(), AssignedProps{0});
+}
+
+TEST(YGStyle, set_properties_reflects_all_set_properties) {
+  auto style = YGStyle{};
+
+  style.direction() = YGDirectionRTL;
+  style.justifyContent() = YGJustifySpaceAround;
+  style.flexWrap() = YGWrapWrap;
+  style.padding()[YGEdgeVertical] = YGValue{1, YGUnitPoint};
+  style.minDimensions()[YGDimensionHeight] = YGValue{1, YGUnitPercent};
+  style.aspectRatio() = YGFloatOptional{1.23};
+
+  ASSERT_EQ(
+      style.assignedProps(),
+      AssignedProps{1ull << YGStyle::directionBit |
+                    1ull << YGStyle::justifyContentBit |
+                    1ull << YGStyle::flexWrapBit |
+                    1ull << (YGStyle::paddingBit + YGEdgeVertical) |
+                    1ull << (YGStyle::minDimensionsBit + YGDimensionHeight) |
+                    1ull << YGStyle::aspectRatioBit});
+}
+
+TEST(YGStyle, directionBit) {
+  constexpr auto directionBit = YGStyle::directionBit;
+  ASSERT_EQ(directionBit, 0);
+}
+TEST(YGStyle, flexDirectionBit) {
+  constexpr auto flexDirectionBit = YGStyle::flexDirectionBit;
+  ASSERT_EQ(flexDirectionBit, 1);
+}
+TEST(YGStyle, justifyContentBit) {
+  constexpr auto justifyContentBit = YGStyle::justifyContentBit;
+  ASSERT_EQ(justifyContentBit, 2);
+}
+TEST(YGStyle, alignContentBit) {
+  constexpr auto alignContentBit = YGStyle::alignContentBit;
+  ASSERT_EQ(alignContentBit, 3);
+}
+TEST(YGStyle, alignItemsBit) {
+  constexpr auto alignItemsBit = YGStyle::alignItemsBit;
+  ASSERT_EQ(alignItemsBit, 4);
+}
+TEST(YGStyle, alignSelfBit) {
+  constexpr auto alignSelfBit = YGStyle::alignSelfBit;
+  ASSERT_EQ(alignSelfBit, 5);
+}
+TEST(YGStyle, positionTypeBit) {
+  constexpr auto positionTypeBit = YGStyle::positionTypeBit;
+  ASSERT_EQ(positionTypeBit, 6);
+}
+TEST(YGStyle, flexWrapBit) {
+  constexpr auto flexWrapBit = YGStyle::flexWrapBit;
+  ASSERT_EQ(flexWrapBit, 7);
+}
+TEST(YGStyle, overflowBit) {
+  constexpr auto overflowBit = YGStyle::overflowBit;
+  ASSERT_EQ(overflowBit, 8);
+}
+TEST(YGStyle, displayBit) {
+  constexpr auto displayBit = YGStyle::displayBit;
+  ASSERT_EQ(displayBit, 9);
+}
+TEST(YGStyle, flexBit) {
+  constexpr auto flexBit = YGStyle::flexBit;
+  ASSERT_EQ(flexBit, 10);
+}
+TEST(YGStyle, flexGrowBit) {
+  constexpr auto flexGrowBit = YGStyle::flexGrowBit;
+  ASSERT_EQ(flexGrowBit, 11);
+}
+TEST(YGStyle, flexShrinkBit) {
+  constexpr auto flexShrinkBit = YGStyle::flexShrinkBit;
+  ASSERT_EQ(flexShrinkBit, 12);
+}
+TEST(YGStyle, flexBasisBit) {
+  constexpr auto flexBasisBit = YGStyle::flexBasisBit;
+  ASSERT_EQ(flexBasisBit, 13);
+}
+TEST(YGStyle, marginBit) {
+  constexpr auto marginBit = YGStyle::marginBit;
+  ASSERT_EQ(marginBit, 14);
+}
+TEST(YGStyle, positionBit) {
+  constexpr auto positionBit = YGStyle::positionBit;
+  ASSERT_EQ(positionBit, 23);
+}
+TEST(YGStyle, paddingBit) {
+  constexpr auto paddingBit = YGStyle::paddingBit;
+  ASSERT_EQ(paddingBit, 32);
+}
+TEST(YGStyle, borderBit) {
+  constexpr auto borderBit = YGStyle::borderBit;
+  ASSERT_EQ(borderBit, 41);
+}
+TEST(YGStyle, dimensionsBit) {
+  constexpr auto dimensionsBit = YGStyle::dimensionsBit;
+  ASSERT_EQ(dimensionsBit, 50);
+}
+TEST(YGStyle, maxDimensionsBit) {
+  constexpr auto maxDimensionsBit = YGStyle::maxDimensionsBit;
+  ASSERT_EQ(maxDimensionsBit, 52);
+}
+TEST(YGStyle, minDimensionsBit) {
+  constexpr auto minDimensionsBit = YGStyle::minDimensionsBit;
+  ASSERT_EQ(minDimensionsBit, 54);
+}
+TEST(YGStyle, aspectRatioBit) {
+  constexpr auto aspectRatioBit = YGStyle::aspectRatioBit;
+  ASSERT_EQ(aspectRatioBit, 56);
+}
+TEST(YGStyle, numStyles) {
+  constexpr auto numStyles = YGStyle::numStyles;
+  ASSERT_EQ(numStyles, 57);
+}
+
+} // namespace yoga
+} // namespace facebook

tests/YGStyleTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGTraversalTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGTreeMutationTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGValueTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

tests/YGZeroOutLayoutRecursivlyTest.cpp

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
  * This source code is licensed under the MIT license found in the LICENSE

testutil/BUCK

@@ -0,0 +1,37 @@
+load("//tools/build_defs/oss:yoga_defs.bzl", "ANDROID", "FBJNI_TARGET", "LIBRARY_COMPILER_FLAGS", "SOLOADER_TARGET", "yoga_cxx_library", "yoga_dep", "yoga_java_library")
+
+yoga_cxx_library(
+    name = "testutil",
+    srcs = ["testutil.cpp"],
+    header_namespace = "yoga/testutil",
+    exported_headers = ["testutil.h"],
+    compiler_flags = LIBRARY_COMPILER_FLAGS,
+    soname = "libyoga_testutil.$(ext)",
+    visibility = ["PUBLIC"],
+    deps = [yoga_dep(":yoga")],
+)
+
+yoga_java_library(
+    name = "java",
+    srcs = ["TestUtil.java"],
+    source = "1.7",
+    target = "1.7",
+    visibility = ["PUBLIC"],
+    deps = [
+        ":jni",
+        SOLOADER_TARGET,
+    ],
+)
+
+yoga_cxx_library(
+    name = "jni",
+    srcs = ["jni.cpp"],
+    compiler_flags = LIBRARY_COMPILER_FLAGS,
+    platforms = ANDROID,
+    soname = "libyoga_testutil_jni.$(ext)",
+    visibility = ["PUBLIC"],
+    deps = [
+        ":testutil",
+        FBJNI_TARGET,
+    ],
+)

testutil/TestUtil.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the LICENSE
+ * file in the root directory of this source tree.
+ */
+package com.facebook.yoga;
+
+import com.facebook.soloader.SoLoader;
+
+class TestUtil {
+  static {
+    SoLoader.loadLibrary("yoga_testutil_jni");
+  }
+
+  static native void startCountingNodes();
+  static native int nodeCount();
+  static native int stopCountingNodes();
+}

testutil/jni.cpp

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the LICENSE
+ * file in the root directory of this source tree.
+ */
+#include <fb/fbjni.h>
+#include <yoga/testutil/testutil.h>
+
+using namespace facebook;
+
+namespace {
+
+void startCountingNodes(jni::alias_ref<jclass>) {
+  yoga::test::TestUtil::startCountingNodes();
+}
+
+jint nodeCount(jni::alias_ref<jclass>) {
+  return yoga::test::TestUtil::nodeCount();
+}
+
+jint stopCountingNodes(jni::alias_ref<jclass>) {
+  return yoga::test::TestUtil::stopCountingNodes();
+}
+
+} // namespace
+
+jint JNI_OnLoad(JavaVM* vm, void*) {
+  return jni::initialize(vm, [] {
+    jni::registerNatives(
+        "com/facebook/yoga/TestUtil",
+        {
+            makeNativeMethod("startCountingNodes", startCountingNodes),
+            makeNativeMethod("nodeCount", nodeCount),
+            makeNativeMethod("stopCountingNodes", stopCountingNodes),
+        });
+  });
+}

testutil/testutil.cpp

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the LICENSE
+ * file in the root directory of this source tree.
+ */
+#include "testutil.h"
+
+#include <yoga/YGNode.h>
+#include <yoga/event/event.h>
+
+namespace facebook {
+namespace yoga {
+namespace test {
+
+int nodeInstanceCount = 0;
+
+namespace {
+
+void yogaEventSubscriber(
+    const YGNode& node,
+    Event::Type eventType,
+    const Event::Data& eventData) {
+
+  switch (eventType) {
+    case Event::NodeAllocation:
+      nodeInstanceCount++;
+      break;
+    case Event::NodeDeallocation:
+      nodeInstanceCount--;
+      break;
+    default:
+      break;
+  }
+}
+} // namespace
+
+void TestUtil::startCountingNodes() {
+  nodeInstanceCount = 0;
+  Event::subscribe(yogaEventSubscriber);
+}
+
+int TestUtil::nodeCount() {
+  return nodeInstanceCount;
+}
+
+int TestUtil::stopCountingNodes() {
+  Event::reset();
+  auto prev = nodeInstanceCount;
+  nodeInstanceCount = 0;
+  return prev;
+}
+
+ScopedEventSubscription::ScopedEventSubscription(
+    std::function<Event::Subscriber>&& s) {
+  Event::subscribe(std::move(s));
+}
+
+ScopedEventSubscription::~ScopedEventSubscription() {
+  Event::reset();
+}
+
+} // namespace test
+} // namespace yoga
+} // namespace facebook

testutil/testutil.h

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the LICENSE
+ * file in the root directory of this source tree.
+ */
+#pragma once
+
+#include <yoga/event/event.h>
+
+#include <functional>
+
+namespace facebook {
+namespace yoga {
+namespace test {
+
+struct TestUtil {
+  static void startCountingNodes();
+  static int nodeCount();
+  static int stopCountingNodes();
+};
+
+struct ScopedEventSubscription {
+  ScopedEventSubscription(std::function<Event::Subscriber>&&);
+  ~ScopedEventSubscription();
+};
+
+} // namespace test
+} // namespace yoga
+} // namespace facebook

tools/build_defs/oss/yoga_defs.bzl

@@ -58,6 +58,7 @@ BASE_COMPILER_FLAGS = [
     "-Wall",
     "-Werror",
     "-O2",
+    "-std=c++11",
 ]
 
 LIBRARY_COMPILER_FLAGS = BASE_COMPILER_FLAGS + [
@@ -148,6 +149,9 @@ def _single_subdir_glob(dirpath, glob_pattern, exclude = None, prefix = None):
 def yoga_dep(dep):
     return "//" + dep
 
+def yoga_cxx_lib(lib):
+    return yoga_dep(lib)
+
 def yoga_android_aar(*args, **kwargs):
     native.android_aar(*args, **kwargs)
 

util/BUCK

@@ -0,0 +1,30 @@
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+load("//tools/build_defs/oss:yoga_defs.bzl", "GTEST_TARGET", "LIBRARY_COMPILER_FLAGS", "yoga_cxx_library", "yoga_cxx_test")
+
+_TESTS = glob(["*Test.cpp"])
+
+yoga_cxx_library(
+    name = "util",
+    srcs = glob(
+        ["*.cpp"],
+        exclude = _TESTS,
+    ),
+    header_namespace = "yoga/util",
+    exported_headers = glob(["*.h"]),
+    compiler_flags = LIBRARY_COMPILER_FLAGS,
+    tests = [":test"],
+    visibility = ["PUBLIC"],
+)
+
+yoga_cxx_test(
+    name = "test",
+    srcs = _TESTS,
+    compiler_flags = LIBRARY_COMPILER_FLAGS,
+    deps = [
+        ":util",
+        GTEST_TARGET,
+    ],
+)

util/SingleWriterValueList.cpp

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the LICENSE
+ * file in the root directory of this source tree.
+ */
+#include "SingleWriterValueList.h"
+
+namespace facebook {
+namespace yoga {
+namespace detail {
+
+void* FreeList::getRaw() {
+  if (free_.size() == 0)
+    return nullptr;
+
+  auto ptr = free_.top();
+  free_.pop();
+  return ptr;
+}
+
+void FreeList::put(std::mutex& mutex, void* ptr) {
+  std::lock_guard<std::mutex> lock{mutex};
+  free_.push(ptr);
+}
+
+FreeList::FreeList() = default;
+FreeList::~FreeList() = default;
+
+} // namespace detail
+} // namespace yoga
+} // namespace facebook

util/SingleWriterValueList.h

@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the LICENSE
+ * file in the root directory of this source tree.
+ */
+#include <forward_list>
+#include <memory>
+#include <mutex>
+#include <stack>
+#include <type_traits>
+#include <utility>
+
+namespace facebook {
+namespace yoga {
+
+namespace detail {
+
+class FreeList {
+  std::stack<void*> free_;
+  void* getRaw();
+
+public:
+  FreeList();
+  ~FreeList();
+
+  void put(std::mutex&, void*);
+
+  template <typename T>
+  T* get() {
+    return static_cast<T*>(getRaw());
+  }
+};
+
+} // namespace detail
+
+/// SingleWriterValueList is a data structure that holds a list of values. Each
+/// value can be borrowed for exclusive writing, and will not be exposed to
+/// another borrower until returned.
+/// Additionaly, the whole list of values can be accessed for reading via const
+/// iterators. Read consistency depends on CPU internals, i.e. whether values
+/// are written to memory atomically.
+///
+/// A typical usage scenario would be a set of threads, where each thread
+/// borrows a value for lock free writing, e.g. as a thread local variable. This
+/// avoids the usage of atomics, or locking of shared memory, which both can
+/// lead to increased latency due to CPU cache flushes and waits.
+///
+/// Values are heap allocated (via forward_list), which typically will avoid
+/// multiple values being allocated in the same CPU cache line, which would also
+/// lead to cache flushing.
+///
+/// SingleWriterValueList never deallocates, to guarantee the validity of
+/// references and iterators. However, memory returned by a borrower can be
+/// borrowed again.
+///
+/// SingleWriterValueList supports return policies as second template parameter,
+/// i.e. an optional mutation of values after a borrower returns them. The
+/// default policy is to do nothing. SingleWriterValueList::resetPolicy is a
+/// convenience method that will move assign the default value of a type.
+///
+/// Example:
+///
+///   static SingleWriterValueList<int> counters;
+///   thread_local auto localCounter = counters.borrow();
+///
+///    /* per thread */
+///    localCounter =+ n;
+///
+///    /* anywhere */
+///    std::accumulate(counters.begin(), counters.end(), 0);
+///
+template <typename T, void (*ReturnPolicy)(T&) = nullptr>
+class SingleWriterValueList {
+  std::forward_list<T> values_{};
+  std::mutex acquireMutex_{};
+  detail::FreeList freeValuesList_{};
+
+  T* allocValue() {
+    values_.emplace_front();
+    return &values_.front();
+  }
+
+  void returnRef(T* value) {
+    if (ReturnPolicy != nullptr) {
+      ReturnPolicy(*value);
+    }
+    freeValuesList_.put(acquireMutex_, value);
+  }
+
+public:
+  using const_iterator = decltype(values_.cbegin());
+
+  /// RAII representation of a single value, borrowed for exclusive writing.
+  /// Instances cannot be copied, and will return the borrowed value to the
+  /// owner upon destruction.
+  class Borrowed {
+    T* value_;
+    SingleWriterValueList* owner_;
+
+  public:
+    Borrowed(T* value, SingleWriterValueList* owner)
+        : value_{value}, owner_{owner} {}
+    ~Borrowed() {
+      if (owner_ != nullptr && value_ != nullptr) {
+        owner_->returnRef(value_);
+      }
+    }
+
+    Borrowed(Borrowed&& other) = default;
+    Borrowed& operator=(Borrowed&& other) = default;
+
+    // no copies allowed
+    Borrowed(const Borrowed&) = delete;
+    Borrowed& operator=(const Borrowed&) = delete;
+
+    T& get() { return *value_; }
+    T& operator*() { return get(); }
+  };
+
+  Borrowed borrow() {
+    std::lock_guard<std::mutex> lock{acquireMutex_};
+    T* value = freeValuesList_.get<T>();
+    return {value != nullptr ? value : allocValue(), this};
+  }
+
+  const_iterator cbegin() const { return values_.cbegin(); };
+  const_iterator cend() const { return values_.cend(); };
+  const_iterator begin() const { return cbegin(); };
+  const_iterator end() const { return cend(); };
+
+  static void resetPolicy(T& value) { value = std::move(T{}); }
+};
+
+} // namespace yoga
+} // namespace facebook

util/SingleWriterValueListTest.cpp

@@ -0,0 +1,163 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the LICENSE
+ * file in the root directory of this source tree.
+ */
+#include <gtest/gtest.h>
+#include <yoga/util/SingleWriterValueList.h>
+
+#include <numeric>
+#include <type_traits>
+#include <unordered_set>
+
+namespace facebook {
+namespace yoga {
+
+static_assert(
+    !std::is_copy_constructible<SingleWriterValueList<int>>::value,
+    "SingleWriterValueList must not be copyable");
+static_assert(
+    !std::is_copy_assignable<SingleWriterValueList<int>>::value,
+    "SingleWriterValueList must not be copyable");
+static_assert(
+    !std::is_copy_constructible<SingleWriterValueList<int>::Borrowed>::value,
+    "SingleWriterValueList::Borrowed must not be copyable");
+static_assert(
+    !std::is_copy_assignable<SingleWriterValueList<int>::Borrowed>::value,
+    "SingleWriterValueList::Borrowed must not be copyable");
+static_assert(
+    std::is_move_constructible<SingleWriterValueList<int>::Borrowed>::value,
+    "SingleWriterValueList::Borrowed must be movable");
+static_assert(
+    std::is_move_assignable<SingleWriterValueList<int>::Borrowed>::value,
+    "SingleWriterValueList::Borrowed must be movable");
+
+TEST(SingleWriterValueList, borrowsAreExclusive) {
+  SingleWriterValueList<int> x{};
+
+  auto a = x.borrow();
+  auto b = x.borrow();
+
+  ASSERT_NE(&a.get(), &b.get());
+}
+
+TEST(SingleWriterValueList, borrowsSupportDereference) {
+  SingleWriterValueList<int> x{};
+
+  auto a = x.borrow();
+  *a = 123;
+
+  ASSERT_EQ(*a, 123);
+}
+
+TEST(SingleWriterValueList, borrowsHaveGetMethod) {
+  SingleWriterValueList<int> x{};
+
+  auto a = x.borrow();
+  a.get() = 123;
+
+  ASSERT_EQ(a.get(), 123);
+}
+
+TEST(SingleWriterValueList, exposesBorrowsViaIterator) {
+  SingleWriterValueList<int> x{};
+
+  auto a = x.borrow();
+  auto b = x.borrow();
+
+  *a = 12;
+  *b = 34;
+
+  int sum = 0;
+  for (auto& i : x) {
+    sum += i;
+  }
+  ASSERT_EQ(sum, 12 + 34);
+}
+
+TEST(SingleWriterValueList, exposesBorrowsViaConstIterator) {
+  SingleWriterValueList<int> x{};
+
+  auto a = x.borrow();
+  auto b = x.borrow();
+
+  *a = 12;
+  *b = 34;
+
+  ASSERT_EQ(std::accumulate(x.cbegin(), x.cend(), 0), 12 + 34);
+}
+
+TEST(SingleWriterValueList, doesNotDeallocateReturnedBorrows) {
+  SingleWriterValueList<int> x{};
+
+  std::unordered_set<const int*> values;
+  {
+    auto a = x.borrow();
+    auto b = x.borrow();
+    values.insert(&a.get());
+    values.insert(&b.get());
+  }
+
+  auto it = x.begin();
+
+  ASSERT_NE(it, x.end());
+  ASSERT_NE(values.find(&*it), values.end());
+
+  ASSERT_NE(++it, x.end());
+  ASSERT_NE(values.find(&*it), values.end());
+}
+
+TEST(SingleWriterValueList, reusesReturnedBorrows) {
+  SingleWriterValueList<int> x{};
+
+  int* firstBorrow;
+  {
+    auto a = x.borrow();
+    firstBorrow = &a.get();
+  }
+
+  auto b = x.borrow();
+
+  ASSERT_EQ(&b.get(), firstBorrow);
+}
+
+TEST(SingleWriterValueList, keepsValuesAfterReturning) {
+  SingleWriterValueList<int> x{};
+
+  {
+    auto a = x.borrow();
+    *a = 123;
+  }
+
+  ASSERT_EQ(*x.begin(), 123);
+}
+
+static void addOne(int& v) {
+  v += 1;
+}
+
+TEST(SingleWriterValueList, allowsCustomReturnPolicy) {
+  SingleWriterValueList<int, addOne> x{};
+
+  {
+    auto a = x.borrow();
+    *a = 123;
+  }
+
+  ASSERT_EQ(*x.begin(), 124);
+}
+
+TEST(SingleWriterValueList, hasConvenienceResetPolicy) {
+  SingleWriterValueList<int, SingleWriterValueList<int>::resetPolicy> x{};
+
+  {
+    auto a = x.borrow();
+    *a = 123;
+  }
+
+  ASSERT_EQ(*x.begin(), 0);
+}
+
+} // namespace yoga
+} // namespace facebook

website/package.json

@@ -32,6 +32,6 @@
     "develop": "gatsby develop"
   },
   "devDependencies": {
-    "prettier": "1.16.4"
+    "prettier": "1.17.0"
   }
 }

website/yarn.lock

@@ -6978,10 +6978,10 @@ preserve@^0.2.0:
   version "0.2.0"
   resolved "https://registry.yarnpkg.com/preserve/-/preserve-0.2.0.tgz#815ed1f6ebc65926f865b310c0713bcb3315ce4b"
 
-prettier@1.16.4:
-  version "1.16.4"
-  resolved "https://registry.yarnpkg.com/prettier/-/prettier-1.16.4.tgz#73e37e73e018ad2db9c76742e2647e21790c9717"
-  integrity sha512-ZzWuos7TI5CKUeQAtFd6Zhm2s6EpAD/ZLApIhsF9pRvRtM1RFo61dM/4MSRUA0SuLugA/zgrZD8m0BaY46Og7g==
+prettier@1.17.0:
+  version "1.17.0"
+  resolved "https://registry.yarnpkg.com/prettier/-/prettier-1.17.0.tgz#53b303676eed22cc14a9f0cec09b477b3026c008"
+  integrity sha512-sXe5lSt2WQlCbydGETgfm1YBShgOX4HxQkFPvbxkcwgDvGDeqVau8h+12+lmSVlP3rHPz0oavfddSZg/q+Szjw==
 
 pretty-bytes@^4.0.2:
   version "4.0.2"