AAPT2: Fix issue with parsing escape sequences when the parser only gives us part at a time

Change-Id: I671955f350b57577a991dd88f6a7319ec0b36c07

5 files changed, 60 insertions, 53 deletions

diff --git a/tools/aapt2/Logger.h b/tools/aapt2/Logger.h
index 1d437ebe6492..eed58b83ffc4 100644
--- a/tools/aapt2/Logger.h
+++ b/tools/aapt2/Logger.h
@@ -18,11 +18,11 @@
 #define AAPT_LOGGER_H
 
 #include "Source.h"
+#include "StringPiece.h"
 
 #include <memory>
 #include <ostream>
 #include <string>
-#include <utils/String8.h>
 
 namespace aapt {
 
@@ -71,11 +71,6 @@ private:
     Source mSource;
 };
 
-inline ::std::ostream& operator<<(::std::ostream& out, const std::u16string& str) {
-    android::String8 utf8(str.data(), str.size());
-    return out.write(utf8.string(), utf8.size());
-}
-
 } // namespace aapt
 
 #endif // AAPT_LOGGER_H
diff --git a/tools/aapt2/StringPiece.h b/tools/aapt2/StringPiece.h
index e2a1597caeda..8cbdeae5e892 100644
--- a/tools/aapt2/StringPiece.h
+++ b/tools/aapt2/StringPiece.h
@@ -229,4 +229,9 @@ inline ::std::ostream& operator<<(::std::ostream& out, const BasicStringPiece<ch
 
 } // namespace aapt
 
+inline ::std::ostream& operator<<(::std::ostream& out, const std::u16string& str) {
+    android::String8 utf8(str.data(), str.size());
+    return out.write(utf8.string(), utf8.size());
+}
+
 #endif // AAPT_STRING_PIECE_H
diff --git a/tools/aapt2/Util.cpp b/tools/aapt2/Util.cpp
index 03ecd1aca310..ca352e0e9b61 100644
--- a/tools/aapt2/Util.cpp
+++ b/tools/aapt2/Util.cpp
@@ -175,7 +175,51 @@ StringBuilder& StringBuilder::append(const StringPiece16& str) {
     const char16_t* start = str.begin();
     const char16_t* current = start;
     while (current != end) {
-        if (*current == u'"') {
+        if (mLastCharWasEscape) {
+            switch (*current) {
+                case u't':
+                    mStr += u'\t';
+                    break;
+                case u'n':
+                    mStr += u'\n';
+                    break;
+                case u'#':
+                    mStr += u'#';
+                    break;
+                case u'@':
+                    mStr += u'@';
+                    break;
+                case u'?':
+                    mStr += u'?';
+                    break;
+                case u'"':
+                    mStr += u'"';
+                    break;
+                case u'\'':
+                    mStr += u'\'';
+                    break;
+                case u'\\':
+                    mStr += u'\\';
+                    break;
+                case u'u': {
+                    current++;
+                    Maybe<char16_t> c = parseUnicodeCodepoint(&current, end);
+                    if (!c) {
+                        mError = "invalid unicode escape sequence";
+                        return *this;
+                    }
+                    mStr += c.value();
+                    current -= 1;
+                    break;
+                }
+
+                default:
+                    // Ignore.
+                    break;
+            }
+            mLastCharWasEscape = false;
+            start = current + 1;
+        } else if (*current == u'"') {
             if (!mQuote && mTrailingSpace) {
                 // We found an opening quote, and we have
                 // trailing space, so we should append that
@@ -208,52 +252,7 @@ StringBuilder& StringBuilder::append(const StringPiece16& str) {
             }
             mStr.append(start, current - start);
             start = current + 1;
-
-            current++;
-            if (current != end) {
-                switch (*current) {
-                    case u't':
-                        mStr += u'\t';
-                        break;
-                    case u'n':
-                        mStr += u'\n';
-                        break;
-                    case u'#':
-                        mStr += u'#';
-                        break;
-                    case u'@':
-                        mStr += u'@';
-                        break;
-                    case u'?':
-                        mStr += u'?';
-                        break;
-                    case u'"':
-                        mStr += u'"';
-                        break;
-                    case u'\'':
-                        mStr += u'\'';
-                        break;
-                    case u'\\':
-                        mStr += u'\\';
-                        break;
-                    case u'u': {
-                        current++;
-                        Maybe<char16_t> c = parseUnicodeCodepoint(&current, end);
-                        if (!c) {
-                            mError = "invalid unicode escape sequence";
-                            return *this;
-                        }
-                        mStr += c.value();
-                        current -= 1;
-                        break;
-                    }
-
-                    default:
-                        // Ignore.
-                        break;
-                }
-                start = current + 1;
-            }
+            mLastCharWasEscape = true;
         } else if (!mQuote) {
             // This is not quoted text, so look for whitespace.
             if (isspace16(*current)) {
diff --git a/tools/aapt2/Util.h b/tools/aapt2/Util.h
index 9cdb152bf41f..7ec6b030fd85 100644
--- a/tools/aapt2/Util.h
+++ b/tools/aapt2/Util.h
@@ -162,6 +162,7 @@ private:
     std::u16string mStr;
     bool mQuote = false;
     bool mTrailingSpace = false;
+    bool mLastCharWasEscape = false;
     std::string mError;
 };
 
diff --git a/tools/aapt2/Util_test.cpp b/tools/aapt2/Util_test.cpp
index 0b08d240cad3..92f2a1c0f1d1 100644
--- a/tools/aapt2/Util_test.cpp
+++ b/tools/aapt2/Util_test.cpp
@@ -38,6 +38,13 @@ TEST(UtilTest, StringStartsWith) {
     EXPECT_TRUE(util::stringStartsWith<char>("hello.xml", "he"));
 }
 
+TEST(UtilTest, StringBuilderSplitEscapeSequence) {
+    EXPECT_EQ(StringPiece16(u"this is a new\nline."),
+            util::StringBuilder().append(u"this is a new\\")
+                                 .append(u"nline.")
+                                 .str());
+}
+
 TEST(UtilTest, StringBuilderWhitespaceRemoval) {
     EXPECT_EQ(StringPiece16(u"hey guys this is so cool"),
             util::StringBuilder().append(u"    hey guys ")