AAPT2: Separate out the various steps

An early refactor. Some ideas became clearer as
development continued. Now the various phases are much
clearer and more easily reusable.

Also added a ton of tests!

Change-Id: Ic8f0a70c8222370352e63533b329c40457c0903e
diff --git a/tools/aapt2/ResourceParser.h b/tools/aapt2/ResourceParser.h
index 7618999..514e558 100644
--- a/tools/aapt2/ResourceParser.h
+++ b/tools/aapt2/ResourceParser.h
@@ -18,14 +18,15 @@
 #define AAPT_RESOURCE_PARSER_H
 
 #include "ConfigDescription.h"
-#include "Logger.h"
+#include "Diagnostics.h"
 #include "ResourceTable.h"
 #include "ResourceValues.h"
-#include "StringPiece.h"
 #include "StringPool.h"
 #include "XmlPullParser.h"
 
-#include <istream>
+#include "util/Maybe.h"
+#include "util/StringPiece.h"
+
 #include <memory>
 
 namespace aapt {
@@ -35,118 +36,12 @@
  */
 class ResourceParser {
 public:
-    /*
-     * Extracts the package, type, and name from a string of the format:
-     *
-     *      [package:]type/name
-     *
-     * where the package can be empty. Validation must be performed on each
-     * individual extracted piece to verify that the pieces are valid.
-     */
-    static void extractResourceName(const StringPiece16& str, StringPiece16* outPackage,
-                                    StringPiece16* outType, StringPiece16* outEntry);
-
-    /*
-     * Returns true if the string was parsed as a reference (@[+][package:]type/name), with
-     * `outReference` set to the parsed reference.
-     *
-     * If '+' was present in the reference, `outCreate` is set to true.
-     * If '*' was present in the reference, `outPrivate` is set to true.
-     */
-    static bool tryParseReference(const StringPiece16& str, ResourceNameRef* outReference,
-                                  bool* outCreate, bool* outPrivate);
-
-    /*
-     * Returns true if the string was parsed as an attribute reference (?[package:]type/name),
-     * with `outReference` set to the parsed reference.
-     */
-    static bool tryParseAttributeReference(const StringPiece16& str,
-                                           ResourceNameRef* outReference);
-
-    /*
-     * Returns true if the string `str` was parsed as a valid reference to a style.
-     * The format for a style parent is slightly more flexible than a normal reference:
-     *
-     * @[package:]style/<entry> or
-     * ?[package:]style/<entry> or
-     * <package>:[style/]<entry>
-     */
-    static bool parseStyleParentReference(const StringPiece16& str, Reference* outReference,
-                                          std::string* outError);
-
-    /*
-     * Returns a Reference object if the string was parsed as a resource or attribute reference,
-     * ( @[+][package:]type/name | ?[package:]type/name ) setting outCreate to true if
-     * the '+' was present in the string.
-     */
-    static std::unique_ptr<Reference> tryParseReference(const StringPiece16& str,
-                                                        bool* outCreate);
-
-    /*
-     * Returns a BinaryPrimitve object representing @null or @empty if the string was parsed
-     * as one.
-     */
-    static std::unique_ptr<BinaryPrimitive> tryParseNullOrEmpty(const StringPiece16& str);
-
-    /*
-     * Returns a BinaryPrimitve object representing a color if the string was parsed
-     * as one.
-     */
-    static std::unique_ptr<BinaryPrimitive> tryParseColor(const StringPiece16& str);
-
-    /*
-     * Returns a BinaryPrimitve object representing a boolean if the string was parsed
-     * as one.
-     */
-    static std::unique_ptr<BinaryPrimitive> tryParseBool(const StringPiece16& str);
-
-    /*
-     * Returns a BinaryPrimitve object representing an integer if the string was parsed
-     * as one.
-     */
-    static std::unique_ptr<BinaryPrimitive> tryParseInt(const StringPiece16& str);
-
-    /*
-     * Returns a BinaryPrimitve object representing a floating point number
-     * (float, dimension, etc) if the string was parsed as one.
-     */
-    static std::unique_ptr<BinaryPrimitive> tryParseFloat(const StringPiece16& str);
-
-    /*
-     * Returns a BinaryPrimitve object representing an enum symbol if the string was parsed
-     * as one.
-     */
-    static std::unique_ptr<BinaryPrimitive> tryParseEnumSymbol(const Attribute& enumAttr,
-                                                               const StringPiece16& str);
-
-    /*
-     * Returns a BinaryPrimitve object representing a flag symbol if the string was parsed
-     * as one.
-     */
-    static std::unique_ptr<BinaryPrimitive> tryParseFlagSymbol(const Attribute& enumAttr,
-                                                               const StringPiece16& str);
-    /*
-     * Try to convert a string to an Item for the given attribute. The attribute will
-     * restrict what values the string can be converted to.
-     * The callback function onCreateReference is called when the parsed item is a
-     * reference to an ID that must be created (@+id/foo).
-     */
-    static std::unique_ptr<Item> parseItemForAttribute(
-            const StringPiece16& value, const Attribute& attr,
-            std::function<void(const ResourceName&)> onCreateReference = {});
-
-    static std::unique_ptr<Item> parseItemForAttribute(
-            const StringPiece16& value, uint32_t typeMask,
-            std::function<void(const ResourceName&)> onCreateReference = {});
-
-    static uint32_t androidTypeToAttributeTypeMask(uint16_t type);
-
-    ResourceParser(const std::shared_ptr<ResourceTable>& table, const Source& source,
-                   const ConfigDescription& config, const std::shared_ptr<XmlPullParser>& parser);
+    ResourceParser(IDiagnostics* diag, ResourceTable* table, const Source& source,
+                   const ConfigDescription& config);
 
     ResourceParser(const ResourceParser&) = delete; // No copy.
 
-    bool parse();
+    bool parse(XmlPullParser* parser);
 
 private:
     /*
@@ -155,7 +50,7 @@
      * contains the escaped and whitespace trimmed text, while `outRawString`
      * contains the unescaped text. Returns true on success.
      */
-    bool flattenXmlSubtree(XmlPullParser* parser, std::u16string* outRawString,\
+    bool flattenXmlSubtree(XmlPullParser* parser, std::u16string* outRawString,
                            StyleString* outStyleString);
 
     /*
@@ -175,19 +70,17 @@
     std::unique_ptr<Attribute> parseAttrImpl(XmlPullParser* parser,
                                              ResourceName* resourceName,
                                              bool weak);
-    bool parseEnumOrFlagItem(XmlPullParser* parser, const StringPiece16& tag,
-                             Attribute::Symbol* outSymbol);
+    Maybe<Attribute::Symbol> parseEnumOrFlagItem(XmlPullParser* parser, const StringPiece16& tag);
     bool parseStyle(XmlPullParser* parser, const ResourceNameRef& resourceName);
-    bool parseUntypedItem(XmlPullParser* parser, Style& style);
+    bool parseStyleItem(XmlPullParser* parser, Style* style);
     bool parseDeclareStyleable(XmlPullParser* parser, const ResourceNameRef& resourceName);
     bool parseArray(XmlPullParser* parser, const ResourceNameRef& resourceName, uint32_t typeMask);
     bool parsePlural(XmlPullParser* parser, const ResourceNameRef& resourceName);
 
-    std::shared_ptr<ResourceTable> mTable;
+    IDiagnostics* mDiag;
+    ResourceTable* mTable;
     Source mSource;
     ConfigDescription mConfig;
-    SourceLogger mLogger;
-    std::shared_ptr<XmlPullParser> mParser;
 };
 
 } // namespace aapt