Function instantiateMappedTupleType

test/fixtures/snapshot/typescript.js:63562–63574

(tupleType, mappedType, mapper)

                createArrayType(elementType, getModifiedReadonlyState(isReadonlyArrayType(arrayType), getMappedTypeModifiers(mappedType)));
        }
        function instantiateMappedTupleType(tupleType, mappedType, mapper) {
            var elementFlags = tupleType.target.elementFlags;
            var elementTypes = ts.map(getTypeArguments(tupleType), function (_, i) {
                return instantiateMappedTypeTemplate(mappedType, getStringLiteralType("" + i), !!(elementFlags[i] & 2 /* ElementFlags.Optional */), mapper);
            });
            var modifiers = getMappedTypeModifiers(mappedType);
            var newTupleModifiers = modifiers & 4 /* MappedTypeModifiers.IncludeOptional */ ? ts.map(elementFlags, function (f) { return f & 1 /* ElementFlags.Required */ ? 2 /* ElementFlags.Optional */ : f; }) :
                modifiers & 8 /* MappedTypeModifiers.ExcludeOptional */ ? ts.map(elementFlags, function (f) { return f & 2 /* ElementFlags.Optional */ ? 1 /* ElementFlags.Required */ : f; }) :
                    elementFlags;
            var newReadonly = getModifiedReadonlyState(tupleType.target.readonly, modifiers);
            return ts.contains(elementTypes, errorType) ? errorType :
                createTupleType(elementTypes, newTupleModifiers, newReadonly, tupleType.target.labeledElementDeclarations);
        }
        function instantiateMappedTypeTemplate(type, key, isOptional, mapper) {
            var templateMapper = appendTypeMapping(mapper, getTypeParameterFromMappedType(type), key);
            var propType = instantiateType(getTemplateTypeFromMappedType(type.target || type), templateMapper);