commit bab4ef56d7803f3a50ccfaca2729509338fcbb23
author Adam Lesinski <adamlesinski@google.com> Thu Jun 01 15:22:57 2017 -0700
committer Adam Lesinski <adamlesinski@google.com> Fri Jun 02 16:48:38 2017 -0700
tree 3d3c1ad103f88f6ca60c46fc31872dee40244b3e
parent d6fb3081d9ddd6384d7e764308e2967ce672d3e5

AAPT2: Allow undefined resources (placeholders)

A resource defined like so:

<item type="drawable" name="foo" />

should be assigned the value @null.

The only exception is for <string> resources, which are given the
empty string value (since <string></string> is ambiguous). The decision
to use "" is based off the fact that old AAPT used to assign "" to all
undefined resources, even non-string ones.

Bug: 38425050
Test: make aapt2_tests
Change-Id: Ib3e0f6f83d16ddd8b279c9fd44a07a37867b85e9

tools/aapt2/link/ReferenceLinker.cpp

diff --git a/tools/aapt2/link/ReferenceLinker.cpp b/tools/aapt2/link/ReferenceLinker.cpp
index 18498e3..a8e510c 100644
--- a/tools/aapt2/link/ReferenceLinker.cpp
+++ b/tools/aapt2/link/ReferenceLinker.cpp
@@ -296,7 +296,10 @@
                                     IAaptContext* context, SymbolTable* symbols,
                                     xml::IPackageDeclStack* decls) {
   CHECK(reference != nullptr);
-  CHECK(reference->name || reference->id);
+  if (!reference->name && !reference->id) {
+    // This is @null.
+    return true;
+  }
 
   Reference transformed_reference = *reference;
   TransformReferenceFromNamespace(decls, context->GetCompilationPackage(), &transformed_reference);