Add generation script header to generated tests

Summary: Add header to generated code so that code can easily be re-generated in case test generation is improved in the future.

Reviewed By: lucasr

Differential Revision: D3715181

fbshipit-source-id: 593baa691c2d7c7f171c6673898fb8a2ecf0e008

gentest/gentest.js

@@ -8,10 +8,10 @@
  */
 
 window.onload = function() {
- printTest(calculateTree(document.body.children[0]));
+ printTest(document.body.children[0], calculateTree(document.body.children[0]));
 }
 
-function printTest(layoutTree) {
+function printTest(rootNode, layoutTree) {
   var lines = [
     '/**',
     ' * Copyright (c) 2014-present, Facebook, Inc.',
@@ -22,11 +22,32 @@ function printTest(layoutTree) {
     ' * of patent rights can be found in the PATENTS file in the same directory.',
     ' */',
     '',
+  ];
+
+  lines.push('/**');
+  lines.push(' * @Generated by gentest/gentest.sh with the following input');
+  lines.push(' *');
+  lines.push(rootNode.innerHTML.split('\n').map(function(line) {
+    return line.trim();
+  }).filter(function(line) {
+    return line.length > 0 && line !== '<div id="default"></div>';
+  }).map(function(line) {
+    return ' * ' + line;
+  }).reduce(function(curr, prev) {
+    return curr + '\n' + prev;
+  }));
+  lines.push(' *');
+  lines.push(' */');
+  lines.push('');
+
+  lines.push([
     '#include <CSSLayout/CSSLayout-internal.h>',
     '#include <CSSLayoutTestUtils/CSSLayoutTestUtils.h>',
     '#include <gtest/gtest.h>',
     '',
-  ];
+  ].reduce(function(curr, prev) {
+    return curr + '\n' + prev;
+  }));
 
   for (var i = 0; i < layoutTree.length - 1; i++) {
     lines.push('TEST(CSSLayoutTest, INSERT_NAME_HERE) {');

tests/CSSLayoutFlexBasisTest.cpp

@@ -7,6 +7,16 @@
  * of patent rights can be found in the PATENTS file in the same directory.
  */
 
+/**
+ * @Generated by gentest/gentest.sh with the following input
+ *
+ * <div style="width: 300px; height: 100px; flex-direction: row;">
+ * <div style="flex-basis: 100px; flex-grow: 1;"></div>
+ * <div style="flex-grow: 1;"></div>
+ * </div>
+ *
+ */
+
 #include <CSSLayout/CSSLayout-internal.h>
 #include <CSSLayoutTestUtils/CSSLayoutTestUtils.h>
 #include <gtest/gtest.h>