2 files changed, 33 insertions, 0 deletions
diff --git a/js/src/frontend/Parser.cpp b/js/src/frontend/Parser.cpp
index f382ec5e9..ffece5721 100644
--- a/js/src/frontend/Parser.cpp
+++ b/js/src/frontend/Parser.cpp
@@ -5124,6 +5124,31 @@ Parser<ParseHandler>::exportBatch(uint32_t begin)
     return exportFrom(begin, kid);
 }
 
+template<>
+bool
+Parser<FullParseHandler>::checkLocalExportNames(ParseNode* node)
+{
+    // ES 2017 draft 15.2.3.1.
+    for (ParseNode* next = node->pn_head; next; next = next->pn_next) {
+        ParseNode* name = next->pn_left;
+        MOZ_ASSERT(name->isKind(PNK_NAME));
+
+        RootedPropertyName ident(context, name->pn_atom->asPropertyName());
+        if (!checkLocalExportName(ident, name->pn_pos.begin))
+            return false;
+    }
+
+    return true;
+}
+
+template<>
+bool
+Parser<SyntaxParseHandler>::checkLocalExportNames(Node node)
+{
+    MOZ_ALWAYS_FALSE(abortIfSyntaxParser());
+    return false;
+}
+
 template <typename ParseHandler>
 typename ParseHandler::Node
 Parser<ParseHandler>::exportClause(uint32_t begin)
@@ -5211,6 +5236,9 @@ Parser<ParseHandler>::exportClause(uint32_t begin)
     if (!matchOrInsertSemicolonAfterNonExpression())
         return null();
 
+    if (!checkLocalExportNames(kid))
+        return null();
+
     Node node = handler.newExportDeclaration(kid, TokenPos(begin, pos().end));
     if (!node)
         return null();
diff --git a/js/src/frontend/Parser.h b/js/src/frontend/Parser.h
index e322a4b26..824dddb58 100644
--- a/js/src/frontend/Parser.h
+++ b/js/src/frontend/Parser.h
@@ -1202,6 +1202,7 @@ class Parser final : public ParserBase, private JS::AutoGCRooter
 
     Node exportFrom(uint32_t begin, Node specList);
     Node exportBatch(uint32_t begin);
+    bool checkLocalExportNames(Node node);
     Node exportClause(uint32_t begin);
     Node exportFunctionDeclaration(uint32_t begin);
     Node exportVariableStatement(uint32_t begin);
@@ -1356,6 +1357,10 @@ class Parser final : public ParserBase, private JS::AutoGCRooter
                                          uint32_t offset,
                                          YieldHandling yieldHandling);
 
+    bool checkLocalExportName(HandlePropertyName ident, uint32_t offset) {
+        return checkLabelOrIdentifierReference(ident, offset, YieldIsName);
+    }
+
     bool checkBindingIdentifier(HandlePropertyName ident,
                                 uint32_t offset,
                                 YieldHandling yieldHandling);