GN: Mark variables in nested scopes used for += and -=.
Previuosly GN would give an unused variable warning when you did += in an inner
scope for a variable defined in an outer scope. This patch marks the outer
variable used in this case.
Review-Url: https://codereview.chromium.org/2393853003
Cr-Original-Commit-Position: refs/heads/master@{#423226}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 80be99d1402bc09c858868b66761d2df77f218b3
diff --git a/tools/gn/operators.cc b/tools/gn/operators.cc
index 9ac18bf..72b2dd1 100644
--- a/tools/gn/operators.cc
+++ b/tools/gn/operators.cc
@@ -155,7 +155,7 @@
const Value* ValueDestination::GetExistingValue() const {
if (type_ == SCOPE)
- return scope_->GetValue(name_token_->value(), false);
+ return scope_->GetValue(name_token_->value(), true);
else if (type_ == LIST)
return &list_->list_value()[index_];
return nullptr;
diff --git a/tools/gn/operators_unittest.cc b/tools/gn/operators_unittest.cc
index 4fa3d11..fa163a1 100644
--- a/tools/gn/operators_unittest.cc
+++ b/tools/gn/operators_unittest.cc
@@ -330,3 +330,34 @@
ASSERT_EQ(Value::SCOPE, new_value->type());
ASSERT_FALSE(new_value->scope_value()->HasValues(Scope::SEARCH_CURRENT));
}
+
+// Tests this case:
+// foo = 1
+// target(...) {
+// foo += 1
+//
+// This should mark the outer "foo" as used, and the inner "foo" as unused.
+TEST(Operators, PlusEqualsUsed) {
+ Err err;
+ TestWithScope setup;
+
+ // Outer "foo" definition, it should be unused.
+ const char foo[] = "foo";
+ Value old_value(nullptr, static_cast<int64_t>(1));
+ setup.scope()->SetValue(foo, old_value, nullptr);
+ EXPECT_TRUE(setup.scope()->IsSetButUnused(foo));
+
+ // Nested scope.
+ Scope nested(setup.scope());
+
+ // Run "foo += 1".
+ TestBinaryOpNode node(Token::PLUS_EQUALS, "+=");
+ node.SetLeftToIdentifier(foo);
+ node.SetRightToValue(Value(nullptr, static_cast<int64_t>(1)));
+ node.Execute(&nested, &err);
+ ASSERT_FALSE(err.has_error());
+
+ // Outer foo should be used, inner foo should not be.
+ EXPECT_FALSE(setup.scope()->IsSetButUnused(foo));
+ EXPECT_TRUE(nested.IsSetButUnused(foo));
+}