private ExprNodeGenericFuncDesc getColumnEqualsConstantExpression(TypeInfo typeInfo,
      String columnName, Object value) {
    ExprNodeDesc column = new ExprNodeColumnDesc(typeInfo, columnName, null, false);
    ExprNodeDesc constant = new ExprNodeConstantDesc(typeInfo, value);
    List<ExprNodeDesc> children = Lists.newArrayList();
    children.add(column);
    children.add(constant);
    ExprNodeGenericFuncDesc node =
        new ExprNodeGenericFuncDesc(typeInfo, new GenericUDFOPEqual(), children);
    return node;
  }
These tests cover the conversion from Hive's AST to SearchArguments.
ql/src/test/org/apache/hadoop/hive/ql/io/sarg/TestConvertAstToSearchArg.java