Added open type builder for extension subtable...

Author: mta452

Tools/Tester/OpenType/Builder.cpp

@@ -614,6 +614,16 @@ ChainContextSubtable &Builder::createChainContext(
     return subtable;
 }
 
+ExtensionSubtable &Builder::createExtension(LookupType lookupType, const LookupSubtable &innerTable)
+{
+    ExtensionSubtable &subtable = createObject<ExtensionSubtable>();
+    subtable.format = 1;
+    subtable.extensionLookupType = lookupType;
+    subtable.extensionTable = (LookupSubtable *)(&innerTable);
+
+    return subtable;
+}
+
 template<class InputIt, class Operation>
 ValueFormat Builder::findValueFormat(InputIt begin, InputIt end, Operation operation)
 {

Tools/Tester/OpenType/Builder.h

@@ -82,6 +82,8 @@ class Builder {
                                              const std::vector<std::vector<Glyph>> lookahead,
                                              const std::vector<std::pair<UInt16, UInt16>> lookups);
 
+    ExtensionSubtable &createExtension(LookupType lookupType, const LookupSubtable &innerTable);
+
     ValueRecord &createValueRecord(const std::array<Int16, 4> metrics,
                                    const std::array<DeviceTable *, 4> devices = {});
 

Tools/Tester/OpenType/Common.h

@@ -700,10 +700,14 @@ struct ChainContextSubtable : public LookupSubtable {
     }
 };
 
-struct ExtensionSubtable : public Table {
+struct ExtensionSubtable : public LookupSubtable {
     UInt16 format;                  // Format identifier
     LookupType extensionLookupType; // Lookup type of subtable referenced by ExtensionOffset (i.e. the extension subtable)
-    Table *extensionTable;          // Offset to the extension subtable, of lookup type ExtensionLookupType, relative to the start of the extension subtable
+    LookupSubtable *extensionTable; // Offset to the extension subtable, of lookup type ExtensionLookupType, relative to the start of the extension subtable
+
+    LookupType lookupType() override {
+        return LookupType::sExtensionSubstitution;
+    }
 
     void write(Writer &writer) override {
         writer.enter();