AAPT2: Adding basic binding support

This is incomplete. Still requires:

- filling in layout information in the resulting .bind.xml
- processing elements with <view class=""/>
- processing imports

Change-Id: Ie5d4c5e6435591bbed3248129a548736244894eb
diff --git a/tools/aapt2/BindingXmlPullParser_test.cpp b/tools/aapt2/BindingXmlPullParser_test.cpp
new file mode 100644
index 0000000..28edcb6
--- /dev/null
+++ b/tools/aapt2/BindingXmlPullParser_test.cpp
@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "SourceXmlPullParser.h"
+#include "BindingXmlPullParser.h"
+
+#include <gtest/gtest.h>
+#include <sstream>
+#include <string>
+
+namespace aapt {
+
+constexpr const char16_t* kAndroidNamespaceUri = u"http://schemas.android.com/apk/res/android";
+
+TEST(BindingXmlPullParserTest, SubstituteBindingExpressionsWithTag) {
+    std::stringstream input;
+    input << "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
+          << "<LinearLayout xmlns:android=\"http://schemas.android.com/apk/res/android\"\n"
+          << "              xmlns:bind=\"http://schemas.android.com/apk/binding\"\n"
+          << "              android:id=\"@+id/content\">\n"
+          << "  <variable name=\"user\" type=\"com.android.test.User\"/>\n"
+          << "  <TextView android:text=\"@{user.name}\" android:layout_width=\"wrap_content\"\n"
+          << "            android:layout_height=\"wrap_content\"/>\n"
+          << "</LinearLayout>\n";
+    std::shared_ptr<XmlPullParser> sourceParser = std::make_shared<SourceXmlPullParser>(input);
+    BindingXmlPullParser parser(sourceParser);
+
+    ASSERT_EQ(XmlPullParser::Event::kStartNamespace, parser.next());
+    EXPECT_EQ(std::u16string(u"http://schemas.android.com/apk/res/android"),
+              parser.getNamespaceUri());
+
+    ASSERT_EQ(XmlPullParser::Event::kStartElement, parser.next());
+    EXPECT_EQ(std::u16string(u"LinearLayout"), parser.getElementName());
+
+    while (parser.next() == XmlPullParser::Event::kText) {}
+
+    ASSERT_EQ(XmlPullParser::Event::kStartElement, parser.getEvent());
+    EXPECT_EQ(std::u16string(u"TextView"), parser.getElementName());
+
+    ASSERT_EQ(3u, parser.getAttributeCount());
+    const auto endAttr = parser.endAttributes();
+    EXPECT_NE(endAttr, parser.findAttribute(kAndroidNamespaceUri, u"layout_width"));
+    EXPECT_NE(endAttr, parser.findAttribute(kAndroidNamespaceUri, u"layout_height"));
+    EXPECT_NE(endAttr, parser.findAttribute(kAndroidNamespaceUri, u"tag"));
+
+    while (parser.next() == XmlPullParser::Event::kText) {}
+
+    ASSERT_EQ(XmlPullParser::Event::kEndElement, parser.getEvent());
+
+    while (parser.next() == XmlPullParser::Event::kText) {}
+
+    ASSERT_EQ(XmlPullParser::Event::kEndElement, parser.getEvent());
+    ASSERT_EQ(XmlPullParser::Event::kEndNamespace, parser.next());
+}
+
+TEST(BindingXmlPullParserTest, GenerateVariableDeclarations) {
+    std::stringstream input;
+    input << "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
+          << "<LinearLayout xmlns:android=\"http://schemas.android.com/apk/res/android\"\n"
+          << "              xmlns:bind=\"http://schemas.android.com/apk/binding\"\n"
+          << "              android:id=\"@+id/content\">\n"
+          << "  <variable name=\"user\" type=\"com.android.test.User\"/>\n"
+          << "</LinearLayout>\n";
+    std::shared_ptr<XmlPullParser> sourceParser = std::make_shared<SourceXmlPullParser>(input);
+    BindingXmlPullParser parser(sourceParser);
+
+    while (XmlPullParser::isGoodEvent(parser.next())) {
+        ASSERT_NE(XmlPullParser::Event::kBadDocument, parser.getEvent());
+    }
+
+    std::stringstream output;
+    ASSERT_TRUE(parser.writeToFile(output));
+
+    std::string result = output.str();
+    EXPECT_NE(std::string::npos,
+              result.find("<entries name=\"user\" type=\"com.android.test.User\"/>"));
+}
+
+TEST(BindingXmlPullParserTest, FailOnMissingNameOrTypeInVariableDeclaration) {
+    std::stringstream input;
+    input << "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
+          << "<LinearLayout xmlns:android=\"http://schemas.android.com/apk/res/android\"\n"
+          << "              xmlns:bind=\"http://schemas.android.com/apk/binding\"\n"
+          << "              android:id=\"@+id/content\">\n"
+          << "  <variable name=\"user\"/>\n"
+          << "</LinearLayout>\n";
+    std::shared_ptr<XmlPullParser> sourceParser = std::make_shared<SourceXmlPullParser>(input);
+    BindingXmlPullParser parser(sourceParser);
+
+    while (XmlPullParser::isGoodEvent(parser.next())) {}
+
+    EXPECT_EQ(XmlPullParser::Event::kBadDocument, parser.getEvent());
+    EXPECT_FALSE(parser.getLastError().empty());
+}
+
+
+} // namespace aapt