Examples with XPathUnsupportedException org.javarosa.xpath.XPathUnsupportedException used on opensource projects

Example 1 with XPathUnsupportedException

use of org.javarosa.xpath.XPathUnsupportedException in project javarosa by opendatakit.

the class XPathEvalTest method doTests.

public void doTests() {
    EvaluationContext ec = getFunctionHandlers();
    FormInstance instance = createTestInstance();
    FormInstance countNonEmptyInstance = createCountNonEmptyTestInstance();
    logTestCategory("counting");
    testEval("count(/data/path)", countNonEmptyInstance, null, 5.0);
    testEval("count-non-empty(/data/path)", countNonEmptyInstance, null, 3);
    logTestCategory("unsupporteds");
    testEval("/union | /expr", new XPathUnsupportedException());
    testEval("/descendant::blah", new XPathUnsupportedException());
    testEval("/cant//support", new XPathUnsupportedException());
    testEval("/text()", new XPathUnsupportedException());
    testEval("/namespace:*", new XPathUnsupportedException());
    testEval("(filter-expr)[5]", instance, null, new XPathUnsupportedException());
    testEval("(filter-expr)/data", instance, null, new XPathUnsupportedException());
    logTestCategory("numeric literals");
    testEval("5", 5.0);
    testEval("555555.555", 555555.555);
    testEval(".000555", 0.000555);
    testEval("0", 0.0);
    testEval("-5", -5.0);
    testEval("-0", -0.0);
    testEval("1230000000000000000000", 1.23e21);
    testEval("0.00000000000000000123", 1.23e-18);
    logTestCategory("string literals");
    testEval("''", "");
    testEval("'\"'", "\"");
    testEval("\"test string\"", "test string");
    testEval("'   '", "   ");
    logTestCategory("type conversions");
    testEval("true()", TRUE);
    testEval("false()", FALSE);
    testEval("boolean(true())", TRUE);
    testEval("boolean(false())", FALSE);
    testEval("boolean(1)", TRUE);
    testEval("boolean(-1)", TRUE);
    testEval("boolean(0.0001)", TRUE);
    testEval("boolean(0)", FALSE);
    testEval("boolean(-0)", FALSE);
    testEval("boolean(number('NaN'))", FALSE);
    testEval("boolean(1 div 0)", TRUE);
    testEval("boolean(-1 div 0)", TRUE);
    testEval("boolean('')", FALSE);
    testEval("boolean('asdf')", TRUE);
    testEval("boolean('  ')", TRUE);
    testEval("boolean('false')", TRUE);
    testEval("boolean(date('2000-01-01'))", TRUE);
    testEval("boolean(convertible())", null, ec, TRUE);
    testEval("boolean(inconvertible())", null, ec, new XPathTypeMismatchException());
    testEval("number(true())", 1.0);
    testEval("number(false())", 0.0);
    testEval("number('100')", 100.0);
    testEval("number('100.001')", 100.001);
    testEval("number('.1001')", 0.1001);
    testEval("number('1230000000000000000000')", 1.23e21);
    testEval("number('0.00000000000000000123')", 1.23e-18);
    testEval("number('0')", 0.0);
    testEval("number('-0')", -0.0);
    testEval("number(' -12345.6789  ')", -12345.6789);
    testEval("number('NaN')", NaN);
    testEval("number('not a number')", NaN);
    testEval("number('- 17')", NaN);
    testEval("number('  ')", NaN);
    testEval("number('')", NaN);
    testEval("number('Infinity')", NaN);
    testEval("number('1.1e6')", NaN);
    testEval("number('34.56.7')", NaN);
    testEval("number(10)", 10.0);
    testEval("number(0)", 0.0);
    testEval("number(-0)", -0.0);
    testEval("number(-123.5)", -123.5);
    testEval("number(number('NaN'))", NaN);
    testEval("number(1 div 0)", POSITIVE_INFINITY);
    testEval("number(-1 div 0)", NEGATIVE_INFINITY);
    testEval("number(date('1970-01-01'))", 0.0);
    testEval("number(date('1970-01-02'))", 1.0);
    testEval("number(date('1969-12-31'))", -1.0);
    testEval("number(date('2008-09-05'))", 14127.0);
    testEval("number(date('1941-12-07'))", -10252.0);
    testEval("number(convertible())", null, ec, 5.0);
    testEval("number(inconvertible())", null, ec, new XPathTypeMismatchException());
    testEval("string(true())", "true");
    testEval("string(false())", "false");
    testEval("string(number('NaN'))", "NaN");
    testEval("string(1 div 0)", "Infinity");
    testEval("string(-1 div 0)", "-Infinity");
    testEval("string(0)", "0");
    testEval("string(-0)", "0");
    testEval("string(123456.0000)", "123456");
    testEval("string(-123456)", "-123456");
    testEval("string(1)", "1");
    testEval("string(-1)", "-1");
    testEval("string(.557586)", "0.557586");
    // broken: testEval("string(1230000000000000000000)", "1230000000000000000000");
    // broken: testEval("string(0.00000000000000000123)", "0.00000000000000000123");
    testEval("string('')", "");
    testEval("string('  ')", "  ");
    testEval("string('a string')", "a string");
    testEval("string(date('1989-11-09'))", "1989-11-09");
    testEval("string(convertible())", null, ec, "hi");
    testEval("string(inconvertible())", null, ec, new XPathTypeMismatchException());
    logTestCategory("substring functions");
    testEval("substr('hello',0)", "hello");
    testEval("substr('hello',0,5)", "hello");
    testEval("substr('hello',1)", "ello");
    testEval("substr('hello',1,5)", "ello");
    testEval("substr('hello',1,4)", "ell");
    testEval("substr('hello',-2)", "lo");
    testEval("substr('hello',0,-1)", "hell");
    testEval("contains('a', 'a')", true);
    testEval("contains('a', 'b')", false);
    testEval("contains('abc', 'b')", true);
    testEval("contains('abc', 'bcd')", false);
    testEval("not(contains('a', 'b'))", true);
    testEval("starts-with('abc', 'a')", true);
    testEval("starts-with('', 'a')", false);
    testEval("starts-with('', '')", true);
    testEval("ends-with('abc', 'a')", false);
    testEval("ends-with('abc', 'c')", true);
    testEval("ends-with('', '')", true);
    logTestCategory("date functions");
    testEval("date('2000-01-01')", DateUtils.getDate(2000, 1, 1));
    testEval("date('1945-04-26')", DateUtils.getDate(1945, 4, 26));
    testEval("date('1996-02-29')", DateUtils.getDate(1996, 2, 29));
    testEval("date('1983-09-31')", new XPathTypeMismatchException());
    testEval("date('not a date')", new XPathTypeMismatchException());
    testEval("date(0)", DateUtils.getDate(1970, 1, 1));
    testEval("date(6.5)", DateUtils.getDate(1970, 1, 7));
    testEval("date(1)", DateUtils.getDate(1970, 1, 2));
    testEval("date(-1)", DateUtils.getDate(1969, 12, 31));
    testEval("date(14127)", DateUtils.getDate(2008, 9, 5));
    testEval("date(-10252)", DateUtils.getDate(1941, 12, 7));
    testEval("date(date('1989-11-09'))", DateUtils.getDate(1989, 11, 9));
    testEval("date(true())", new XPathTypeMismatchException());
    testEval("date(convertible())", null, ec, new XPathTypeMismatchException());
    // note: there are lots of time and timezone-like issues with dates that should be tested (particularly DST changes),
    // but it's just too hard and client-dependent, so not doing it now
    // basically:
    // dates cannot reliably be compared/used across time zones (an issue with the code)
    // any time-of-day or DST should be ignored when comparing/using a date (an issue with testing)
    /* other built-in functions */
    testEval("format-date('2018-01-02T10:20:30.123', \"%Y-%m-%e %H:%M:%S\")", "2018-01-2 10:20:30");
    logTestCategory("boolean functions");
    testEval("not(true())", FALSE);
    testEval("not(false())", TRUE);
    testEval("not('')", TRUE);
    testEval("boolean-from-string('true')", TRUE);
    testEval("boolean-from-string('false')", FALSE);
    testEval("boolean-from-string('whatever')", FALSE);
    testEval("boolean-from-string('1')", TRUE);
    testEval("boolean-from-string('0')", FALSE);
    testEval("boolean-from-string(1)", TRUE);
    testEval("boolean-from-string(1.0)", TRUE);
    testEval("boolean-from-string(1.0001)", FALSE);
    testEval("boolean-from-string(true())", TRUE);
    testEval("if(true(), 5, 'abc')", 5.0);
    testEval("if(false(), 5, 'abc')", "abc");
    testEval("if(6 > 7, 5, 'abc')", "abc");
    testEval("if('', 5, 'abc')", "abc");
    testEval("selected('apple baby crimson', 'apple')", TRUE);
    testEval("selected('apple baby crimson', 'baby')", TRUE);
    testEval("selected('apple baby crimson', 'crimson')", TRUE);
    testEval("selected('apple baby crimson', '  baby  ')", TRUE);
    testEval("selected('apple baby crimson', 'babby')", FALSE);
    testEval("selected('apple baby crimson', 'bab')", FALSE);
    testEval("selected('apple', 'apple')", TRUE);
    testEval("selected('apple', 'ovoid')", FALSE);
    testEval("selected('', 'apple')", FALSE);
    logTestCategory("math operators");
    testEval("5.5 + 5.5", 11.0);
    testEval("0 + 0", 0.0);
    testEval("6.1 - 7.8", -1.7);
    testEval("-3 + 4", 1.0);
    testEval("3 + -4", -1.0);
    testEval("1 - 2 - 3", -4.0);
    testEval("1 - (2 - 3)", 2.0);
    testEval("-(8*5)", -40.0);
    testEval("-'19'", -19.0);
    testEval("1.1 * -1.1", -1.21);
    testEval("-10 div -4", 2.5);
    testEval("2 * 3 div 8 * 2", 1.5);
    testEval("3 + 3 * 3", 12.0);
    testEval("1 div 0", POSITIVE_INFINITY);
    testEval("-1 div 0", NEGATIVE_INFINITY);
    testEval("0 div 0", NaN);
    testEval("3.1 mod 3.1", 0.0);
    testEval("5 mod 3.1", 1.9);
    testEval("2 mod 3.1", 2.0);
    testEval("0 mod 3.1", 0.0);
    testEval("5 mod -3", 2.0);
    testEval("-5 mod 3", -2.0);
    testEval("-5 mod -3", -2.0);
    testEval("5 mod 0", NaN);
    testEval("5 * (6 + 7)", 65.0);
    testEval("'123' * '456'", 56088.0);
    logTestCategory("math functions");
    testEval("abs(-3.5)", 3.5);
    // round, with a single argument
    testEval("round('14.29123456789')", 14.0);
    testEval("round('14.6')", 15.0);
    // round, with two arguments
    testEval("round('14.29123456789', 0)", 14.0);
    testEval("round('14.29123456789', 1)", 14.3);
    testEval("round('14.29123456789', 1.5)", 14.3);
    testEval("round('14.29123456789', 2)", 14.29);
    testEval("round('14.29123456789', 3)", 14.291);
    testEval("round('14.29123456789', 4)", 14.2912);
    testEval("round('12345.14',     1)", 12345.1);
    testEval("round('-12345.14',    1)", -12345.1);
    testEval("round('12345.12345',  0)", 12345.0);
    testEval("round('12345.12345', -1)", 12350.0);
    testEval("round('12345.12345', -2)", 12300.0);
    testEval("round('12350.12345', -2)", 12400.0);
    testEval("round('12345.12345', -3)", 12000.0);
    // round, with a comma instead of a decimal point
    testEval("round('4,6'            )", 5.0);
    // XPath specification tests
    testEval("round('1 div 0', 0)", NaN);
    testEval("round('14.5')", 15.0);
    testEval("round('NaN')", NaN);
    testEval("round('-NaN')", -NaN);
    testEval("round('0')", 0.0);
    testEval("round('-0')", -0.0);
    testEval("round('-0.5')", -0.0);
    // non US format
    testEval("round('14,6')", 15.0);
    // Java 8 tests deprecated by XPath 3.0 specification
    // See discussion at https://github.com/opendatakit/javarosa/pull/42#issuecomment-299527754
    testEval("round('12345.15',     1)", 12345.2);
    testEval("round('-12345.15',    1)", -12345.1);
    logTestCategory("strange operators");
    testEval("true() + 8", 9.0);
    testEval("date('2008-09-08') - date('1983-10-06')", 9104.0);
    testEval("true() and true()", TRUE);
    testEval("true() and false()", FALSE);
    testEval("false() and false()", FALSE);
    testEval("true() or true()", TRUE);
    testEval("true() or false()", TRUE);
    testEval("false() or false()", FALSE);
    testEval("true() or true() and false()", TRUE);
    testEval("(true() or true()) and false()", FALSE);
    // short-circuiting
    testEval("true() or date('')", TRUE);
    // short-circuiting
    testEval("false() and date('')", FALSE);
    testEval("'' or 17", TRUE);
    testEval("false() or 0 + 2", TRUE);
    testEval("(false() or 0) + 2", 2.0);
    testEval("4 < 5", TRUE);
    testEval("5 < 5", FALSE);
    testEval("6 < 5", FALSE);
    testEval("4 <= 5", TRUE);
    testEval("5 <= 5", TRUE);
    testEval("6 <= 5", FALSE);
    testEval("4 > 5", FALSE);
    testEval("5 > 5", FALSE);
    testEval("6 > 5", TRUE);
    testEval("4 >= 5", FALSE);
    testEval("5 >= 5", TRUE);
    testEval("6 >= 5", TRUE);
    testEval("-3 > -6", TRUE);
    logTestCategory("odd comparisons");
    testEval("true() > 0.9999", TRUE);
    // no string comparison: converted to number
    testEval("'-17' > '-172'", TRUE);
    // no string comparison: converted to NaN
    testEval("'abc' < 'abcd'", FALSE);
    testEval("date('2001-12-26') > date('2001-12-25')", TRUE);
    testEval("date('1969-07-20') < date('1969-07-21')", TRUE);
    testEval("false() and false() < true()", FALSE);
    testEval("(false() and false()) < true()", TRUE);
    testEval("6 < 7 - 4", FALSE);
    testEval("(6 < 7) - 4", -3.0);
    testEval("3 < 4 < 5", TRUE);
    testEval("3 < (4 < 5)", FALSE);
    testEval("true() = true()", TRUE);
    testEval("true() = false()", FALSE);
    testEval("true() != true()", FALSE);
    testEval("true() != false()", TRUE);
    testEval("3 = 3", TRUE);
    testEval("3 = 4", FALSE);
    testEval("3 != 3", FALSE);
    testEval("3 != 4", TRUE);
    // handle floating point rounding
    testEval("6.1 - 7.8 = -1.7", TRUE);
    testEval("'abc' = 'abc'", TRUE);
    testEval("'abc' = 'def'", FALSE);
    testEval("'abc' != 'abc'", FALSE);
    testEval("'abc' != 'def'", TRUE);
    testEval("'' = ''", TRUE);
    testEval("true() = 17", TRUE);
    testEval("0 = false()", TRUE);
    testEval("true() = 'true'", TRUE);
    testEval("17 = '17.0000000'", TRUE);
    testEval("'0017.' = 17", TRUE);
    testEval("'017.' = '17.000'", FALSE);
    testEval("date('2004-05-01') = date('2004-05-01')", TRUE);
    testEval("true() != date('1999-09-09')", FALSE);
    testEval("false() and true() != true()", FALSE);
    testEval("(false() and true()) != true()", TRUE);
    testEval("-3 < 3 = 6 >= 6", TRUE);
    logTestCategory("functions, including custom function handlers");
    testEval("true(5)", new XPathUnhandledException());
    testEval("number()", new XPathUnhandledException());
    testEval("string('too', 'many', 'args')", new XPathUnhandledException());
    testEval("not-a-function()", new XPathUnhandledException());
    testEval("testfunc()", null, ec, TRUE);
    testEval("add(3, 5)", null, ec, 8.0);
    testEval("add('17', '-14')", null, ec, 3.0);
    logTestCategory("proto");
    testEval("proto()", null, ec, new XPathTypeMismatchException());
    testEval("proto(5, 5)", null, ec, "[Double:5.0,Double:5.0]");
    testEval("proto(6)", null, ec, "[Double:6.0]");
    testEval("proto('asdf')", null, ec, "[Double:NaN]");
    // note: args treated as doubles because
    testEval("proto('7', '7')", null, ec, "[Double:7.0,Double:7.0]");
    // (double, double) prototype takes precedence and strings are convertible to doubles
    testEval("proto(1.1, 'asdf', true())", null, ec, "[Double:1.1,String:asdf,Boolean:true]");
    testEval("proto(false(), false(), false())", null, ec, "[Double:0.0,String:false,Boolean:false]");
    testEval("proto(1.1, 'asdf', inconvertible())", null, ec, new XPathTypeMismatchException());
    testEval("proto(1.1, 'asdf', true(), 16)", null, ec, new XPathTypeMismatchException());
    logTestCategory("raw");
    testEval("raw()", null, ec, "[]");
    testEval("raw(5, 5)", null, ec, "[Double:5.0,Double:5.0]");
    testEval("raw('7', '7')", null, ec, "[String:7,String:7]");
    // convertible to prototype
    testEval("raw('1.1', 'asdf', 17)", null, ec, "[Double:1.1,String:asdf,Boolean:true]");
    testEval("raw(get-custom(false()), get-custom(true()))", null, ec, "[CustomType:,CustomSubType:]");
    logTestCategory("concat");
    testEval("concat()", null, ec, "");
    testEval("concat('a')", null, ec, "a");
    testEval("concat('a','b','')", null, ec, "ab");
    testEval("concat('ab','cde','','fgh',1,false(),'ijklmnop')", null, ec, "abcdefgh1falseijklmnop");
    testEval("check-types(55, '55', false(), '1999-09-09', get-custom(false()))", null, ec, TRUE);
    testEval("check-types(55, '55', false(), '1999-09-09', get-custom(true()))", null, ec, TRUE);
    logTestCategory("regex");
    testEval("regex('12345','[0-9]+')", null, ec, TRUE);
    testEval("pow(2, 2)", 4.0);
    testEval("pow(2, 0)", 1.0);
    testEval("pow(0, 4)", 0.0);
    testEval("pow(2.5, 2)", 6.25);
    testEval("pow(0.5, 2)", .25);
    testEval("pow(-1, 2)", 1.0);
    testEval("pow(-1, 3)", -1.0);
    // So raising things to decimal powers is.... very hard
    // to evaluated exactly due to double floating point
    // precision. We'll try for things with clean answers
    testEval("pow(4, 0.5)", 2.0);
    testEval("pow(16, 0.25)", 2.0);
    logTestCategory("variable refs");
    EvaluationContext varContext = getVariableContext();
    testEval("$var_float_five", null, varContext, 5.0);
    testEval("$var_string_five", null, varContext, "five");
    testEval("$var_int_five", null, varContext, 5.0);
    testEval("$var_double_five", null, varContext, 5.0);
    logTestCategory("node referencing");
    // happy flow scenario where the index node is not blank
    FormInstance testInstance = createTestDataForIndexedRepeatFunction(1);
    XPathNodeset expected = createExpectedNodesetFromIndexedRepeatFunction(testInstance, 1, "name");
    testEval("indexed-repeat( /data/repeat/name , /data/repeat , /data/index1 )", testInstance, null, expected);
    // situation where the referenced index node is blank and the default value (0 which means the first repeat group) is used
    testInstance = createTestDataForIndexedRepeatFunction(null);
    expected = createExpectedNodesetFromIndexedRepeatFunction(testInstance, 0, "name");
    testEval("indexed-repeat( /data/repeat/name , /data/repeat , /data/index1 )", testInstance, null, expected);
    logTestCategory("crypto functions");
    // Support for all 5 supported digest algorithms (required and optional) and default base64 encoding
    testEval("digest('some text', 'MD5', 'base64')", "VS4hzUzZkYZ448Gg30kbww==");
    testEval("digest('some text', 'SHA-1', 'base64')", "N6pjx3OY2VRHMmLhoAV8HmMu2nc=");
    testEval("digest('some text', 'SHA-256', 'base64')", "uU9vElx546X/qoJvWEwQ1SraZp5nYgUbgmtVd20FrtI=");
    testEval("digest('some text', 'SHA-384', 'base64')", "zJTsPphzwLmnJIZEKVj2cQZ833e5QnQW0DFEDMYgQeLuE0RJhEfsDO2fcENGG9Hz");
    testEval("digest('some text', 'SHA-512', 'base64')", "4nMrrtyj6sFAeChjfeHbynAsP8ns4Wz1Nt241hOc2F3+dGS4I1spgm9gjM9KxkPimxnGN4WKPYcQpZER30LdtQ==");
    // Support for hexadecimal encoding
    testEval("digest('some text', 'MD5', 'hex')", "552e21cd4cd9918678e3c1a0df491bc3");
    // Support for optional third argument (defaults to 'base64')
    testEval("digest('some text', 'MD5')", "VS4hzUzZkYZ448Gg30kbww==");
    try {
        testEval("null-proto()", null, ec, new XPathUnhandledException());
        fail("Did not get expected null pointer");
    } catch (NullPointerException npe) {
    // expected
    }
    ec.addFunctionHandler(read);
    ec.addFunctionHandler(write);
    read.val = "testing-read";
    testEval("read()", null, ec, "testing-read");
    testEval("write('testing-write')", null, ec, TRUE);
    if (!"testing-write".equals(write.val))
        fail("Custom function handler did not successfully send data to external source");
}

Example 2 with XPathUnsupportedException

use of org.javarosa.xpath.XPathUnsupportedException in project javarosa by opendatakit.

the class XPathPathExpr method getReference.

/**
 * translate an xpath path reference into a TreeReference
 * TreeReferences only support a subset of true xpath paths; restrictions are:
 *   simple child name tests 'child::name', '.', and '..' allowed only
 *   no predicates
 *   all '..' steps must come before anything else
 */
public TreeReference getReference(boolean allowPredicates) throws XPathUnsupportedException {
    TreeReference ref = new TreeReference();
    boolean parentsAllowed;
    switch(init_context) {
        case XPathPathExpr.INIT_CONTEXT_ROOT:
            ref.setRefLevel(TreeReference.REF_ABSOLUTE);
            parentsAllowed = false;
            break;
        case XPathPathExpr.INIT_CONTEXT_RELATIVE:
            ref.setRefLevel(0);
            parentsAllowed = true;
            break;
        case XPathPathExpr.INIT_CONTEXT_EXPR:
            if (this.filtExpr.x != null && this.filtExpr.x instanceof XPathFuncExpr) {
                XPathFuncExpr func = (XPathFuncExpr) (this.filtExpr.x);
                if (func.id.toString().equals("instance")) {
                    // i assume when refering the non main instance you have to be absolute
                    ref.setRefLevel(TreeReference.REF_ABSOLUTE);
                    parentsAllowed = false;
                    if (func.args.length != 1) {
                        throw new XPathUnsupportedException("instance() function used with " + func.args.length + " arguements. Expecting 1 arguement");
                    }
                    if (!(func.args[0] instanceof XPathStringLiteral)) {
                        throw new XPathUnsupportedException("instance() function expecting 1 string literal arguement arguement");
                    }
                    XPathStringLiteral strLit = (XPathStringLiteral) (func.args[0]);
                    // we've got a non-standard instance in play, watch out
                    if (strLit.s == null) {
                        // absolute reference to the main instance
                        ref.setContext(TreeReference.CONTEXT_ABSOLUTE);
                        ref.setInstanceName(null);
                    } else {
                        ref.setContext(TreeReference.CONTEXT_INSTANCE);
                        ref.setInstanceName(strLit.s);
                    }
                } else if (func.id.toString().equals("current")) {
                    parentsAllowed = true;
                    ref.setContext(TreeReference.CONTEXT_ORIGINAL);
                } else {
                    // We only support expression root contexts for instance refs, everything else is an illegal filter
                    throw new XPathUnsupportedException("filter expression");
                }
            } else {
                // We only support expression root contexts for instance refs, everything else is an illegal filter
                throw new XPathUnsupportedException("filter expression");
            }
            break;
        default:
            throw new XPathUnsupportedException("filter expression");
    }
    for (int i = 0; i < steps.length; i++) {
        XPathStep step = steps[i];
        if (step.axis == XPathStep.AXIS_SELF) {
            if (step.test != XPathStep.TEST_TYPE_NODE) {
                throw new XPathUnsupportedException("step other than 'child::name', '.', '..'");
            }
        } else if (step.axis == XPathStep.AXIS_PARENT) {
            if (!parentsAllowed || step.test != XPathStep.TEST_TYPE_NODE) {
                throw new XPathUnsupportedException("step other than 'child::name', '.', '..'");
            } else {
                ref.incrementRefLevel();
            }
        } else if (step.axis == XPathStep.AXIS_ATTRIBUTE) {
            if (step.test == XPathStep.TEST_NAME) {
                ref.add(step.name.toString(), TreeReference.INDEX_ATTRIBUTE);
                parentsAllowed = false;
            // TODO: Can you step back from an attribute, or should this always be
            // the last step?
            } else {
                throw new XPathUnsupportedException("attribute step other than 'attribute::name");
            }
        } else if (step.axis == XPathStep.AXIS_CHILD) {
            if (step.test == XPathStep.TEST_NAME) {
                ref.add(step.name.toString(), TreeReference.INDEX_UNBOUND);
                parentsAllowed = true;
            } else if (step.test == XPathStep.TEST_NAME_WILDCARD) {
                ref.add(TreeReference.NAME_WILDCARD, TreeReference.INDEX_UNBOUND);
                parentsAllowed = true;
            } else {
                throw new XPathUnsupportedException("step other than 'child::name', '.', '..'");
            }
        } else {
            throw new XPathUnsupportedException("step other than 'child::name', '.', '..'");
        }
        if (step.predicates.length > 0) {
            int refLevel = ref.getRefLevel();
            List<XPathExpression> v = new ArrayList<XPathExpression>(step.predicates.length);
            for (int j = 0; j < step.predicates.length; j++) {
                v.add(step.predicates[j]);
            }
            ref.addPredicate(i, v);
        }
    }
    return ref;
}