Add <macro> tag to aapt2

AAPT2 Macros are compile-time resources definitions that are expanded
when referenced during the link phase.

A macro must be defined in the res/values.xml directory. A macro
definition for a macro named "foo" looks like the following:
 <macro name="foo">contents</macro>

When "@macro/foo" is used in the res/values directory or in a compiled
XML file, the contents of the macro replace the macro reference and
then the substituted contents are compiled and linked. If the macro
contents reference xml namespaces from its original definition, the
namespaces of the original macro definition will be used to determine
which package is being referenced.

Macros can be used anywhere resources can be referenced using the
@package:type/entry syntax.

Macros are not included in the final resource table or the R.java since
they are not actual resources.

Bug: 175616308
Test: aapt2_tests
Change-Id: I48b29ab6564357b32b4b4e32bff7ef06036382bc

1 files changed, 17 insertions, 3 deletions

diff --git a/tools/aapt2/ResourceParser.h b/tools/aapt2/ResourceParser.h
index af0db8c0ba2c..5c92def50616 100644
--- a/tools/aapt2/ResourceParser.h
+++ b/tools/aapt2/ResourceParser.h
@@ -57,6 +57,14 @@ struct ResourceParserOptions {
   Maybe<Visibility::Level> visibility;
 };
 
+struct FlattenedXmlSubTree {
+  std::string raw_value;
+  StyleString style_string;
+  std::vector<UntranslatableSection> untranslatable_sections;
+  xml::IPackageDeclStack* namespace_resolver;
+  Source source;
+};
+
 /*
  * Parses an XML file for resources and adds them to a ResourceTable.
  */
@@ -67,9 +75,16 @@ class ResourceParser {
                  const ResourceParserOptions& options = {});
   bool Parse(xml::XmlPullParser* parser);
 
+  static std::unique_ptr<Item> ParseXml(const FlattenedXmlSubTree& xmlsub_tree, uint32_t type_mask,
+                                        bool allow_raw_value, ResourceTable& table,
+                                        const android::ConfigDescription& config,
+                                        IDiagnostics& diag);
+
  private:
   DISALLOW_COPY_AND_ASSIGN(ResourceParser);
 
+  std::optional<FlattenedXmlSubTree> CreateFlattenSubTree(xml::XmlPullParser* parser);
+
   // Parses the XML subtree as a StyleString (flattened XML representation for strings with
   // formatting). If parsing fails, false is returned and the out parameters are left in an
   // unspecified state. Otherwise,
@@ -96,7 +111,7 @@ class ResourceParser {
 
   bool ParseItem(xml::XmlPullParser* parser, ParsedResource* out_resource, uint32_t format);
   bool ParseString(xml::XmlPullParser* parser, ParsedResource* out_resource);
-
+  bool ParseMacro(xml::XmlPullParser* parser, ParsedResource* out_resource);
   bool ParsePublic(xml::XmlPullParser* parser, ParsedResource* out_resource);
   bool ParsePublicGroup(xml::XmlPullParser* parser, ParsedResource* out_resource);
   bool ParseStagingPublicGroup(xml::XmlPullParser* parser, ParsedResource* out_resource);
@@ -108,8 +123,7 @@ class ResourceParser {
   bool ParseAttrImpl(xml::XmlPullParser* parser, ParsedResource* out_resource, bool weak);
   Maybe<Attribute::Symbol> ParseEnumOrFlagItem(xml::XmlPullParser* parser,
                                                const android::StringPiece& tag);
-  bool ParseStyle(const ResourceType type, xml::XmlPullParser* parser,
-                  ParsedResource* out_resource);
+  bool ParseStyle(ResourceType type, xml::XmlPullParser* parser, ParsedResource* out_resource);
   bool ParseStyleItem(xml::XmlPullParser* parser, Style* style);
   bool ParseDeclareStyleable(xml::XmlPullParser* parser, ParsedResource* out_resource);
   bool ParseArray(xml::XmlPullParser* parser, ParsedResource* out_resource);