Chapter 24. Repeat Task
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## Chapter 24. Repeat Task

The Repeat task performs the same subtasks over and over a certain number of times or until a condition is met. Since most tasks are configured when the build file is first loaded and never again, this task may not do what you want.

To use this task in your build files, include a task definition like this:

        <taskdef name="call" classname="ise.antelope.tasks.Repeat"/>

Table 24.1. Repeat Task Attributes

Attribute | Description | Default | Required
--- | --- | --- | ---
count | The number of times to repeat execution of the nested tasks. | 1 | No
interval | How long to wait between repetitions. If set to 0, only 1 repetition will be performed, this is to avoid a tight loop. | 0 | No
unit | The units for interval, allowed values are "milliseconds", "seconds", "minutes", "days", and "weeks" | seconds | No
property | The name of a property to set upon completion. | None | No
value | The value to set for the property to be set upon completion. | None | No

Here are a number of examples taken from the unit tests for this task:

       <target name="test1a">
          <!-- no count set, verify performs tasks once -->
          <a:var name="count" value="0"/>
          <a:repeat>
             <a:math result="count" operand1="${count}" operand2="1" operation="+"/>
          </a:repeat>
          <a:assert>
             <bool>
                <mathequals arg1="${count}" arg2="1"/>
             </bool>
          </a:assert>
       </target>

       <target name="test1b">
          <!-- count > 1, verify performs tasks correct number of times -->
          <a:var name="count" value="0"/>
          <a:repeat count="3" interval="1">
             <a:math result="count" operand1="${count}" operand2="1" operation="+"/>
          </a:repeat>
          <a:assert message="Expected 3, got ${count}">
             <bool>
                <mathequals arg1="${count}" arg2="3"/>
             </bool>
          </a:assert>
       </target>

       <target name="test1c">
          <!-- count = -1, verify performs tasks indefinitely -->
          <a:var name="count" value="0"/>
          <a:limit maxwait="10">
             <a:repeat count="-1" interval="1">
                <a:math result="count" operand1="${count}" operand2="1" operation="+"/>
             </a:repeat>
          </a:limit>
          <a:assert>
             <bool>
                <and>
                   <a:isgreaterthan arg1="${count}" arg2="8"/>
                   <a:islessthan arg1="${count}" arg2="12"/>
                </and>
             </bool>
          </a:assert>
       </target>

       <target name="test2a">
          <!-- no interval set, verify performs tasks 10 seconds apart -->
          <a:var name="count" value="0"/>
          <a:stopwatch name="test2a_stopwatch" action="start"/>
          <a:repeat count="2">
             <a:math result="count" operand1="${count}" operand2="1" operation="+"/>
          </a:repeat>
          <a:stopwatch name="test2a_stopwatch" action="total"/>
          <a:assert message="Got ${count}, expected 2">
             <bool>
                <and>
                   <a:mathequals arg1="${count}" arg2="2"/>
                   <a:islessthan arg1="${test2a_stopwatch}" arg2="11"/>
                </and>
             </bool>
          </a:assert>
       </target>

       <target name="test2b">
          <!-- interval set to other than 10 seconds, verify tasks performed correct
               time apart. -->
          <a:var name="count" value="0"/>
          <a:stopwatch name="test2b_stopwatch" action="start"/>
          <a:repeat count="2" interval="5">
             <a:math result="count" operand1="${count}" operand2="1" operation="+"/>
          </a:repeat>
          <a:stopwatch name="test2b_stopwatch" action="total"/>
          <a:assert>
             <bool>
                <and>
                   <a:mathequals arg1="${count}" arg2="2"/>
                   <a:islessthan arg1="${test2b_stopwatch}" arg2="6"/>
                </and>
             </bool>
          </a:assert>
       </target>

       <target name="test2c">
          <!-- interval = 0, verify tasks performed just once -->
          <a:var name="count" value="0"/>
          <a:stopwatch name="test2c_stopwatch" action="start"/>
          <a:repeat count="5" interval="0">
             <a:math result="count" operand1="${count}" operand2="1" operation="+" datatype="int"/>
          </a:repeat>
          <a:stopwatch name="test2c_stopwatch" action="total"/>
          <a:assert>
             <bool>
                <and>
                   <a:mathequals arg1="${count}" arg2="1"/>
                   <a:islessthan arg1="${test2c_stopwatch}" arg2="1"/>
                </and>
             </bool>
          </a:assert>
       </target>

       <target name="test3a">
          <!-- failOnError not set, verify continues to execute tasks even if one fails -->
          <a:var name="count" value="0"/>
          <a:repeat count="3" interval="1">
             <a:math result="count" operand1="${count}" operand2="1" operation="+"/>
             <fail/>
          </a:repeat>
          <a:assert>
             <bool>
                <a:mathequals arg1="${count}" arg2="3"/>
             </bool>
          </a:assert>
       </target>

       <target name="test3b">
          <!-- failOnError set to false, same as 3a -->
          <a:var name="count" value="0"/>
          <a:repeat count="3" interval="1" failonerror="no">
             <a:math result="count" operand1="${count}" operand2="1" operation="+"/>
             <fail/>
          </a:repeat>
          <a:assert>
             <bool>
                <a:mathequals arg1="${count}" arg2="3"/>
             </bool>
          </a:assert>
       </target>

       <target name="test3c">
          <!-- failOnError set to true, verify build fails if subtask fails -->
          <a:var name="count" value="0"/>
          <a:try>
             <a:repeat count="3" interval="1" failonerror="yes">
                <a:math result="count" operand1="${count}" operand2="1" operation="+"/>
                <fail/>
             </a:repeat>
          </a:try>
          <a:assert>
             <bool>
                <a:mathequals arg1="${count}" arg2="1"/>
             </bool>
          </a:assert>
       </target>

       <target name="test4a">
          <!-- property name set, value not set, verify property is set to true when task
               is complete -->
          <a:var name="count" value="0"/>
          <a:repeat count="1" interval="1" property="test4a_property">
             <a:math result="count" operand1="${count}" operand2="1" operation="+"/>
             <fail/>
          </a:repeat>
          <a:assert>
             <bool>
                <istrue value="${test4a_property}"/>
             </bool>
          </a:assert>
       </target>

       <target name="test4b">
          <!-- property ame set, value set to a specific value, verify property is set to
               specific value when task is complete -->
          <a:var name="count" value="0"/>
          <a:repeat count="1" interval="1" property="test4b_property" value="good">
             <a:math result="count" operand1="${count}" operand2="1" operation="+"/>
             <fail/>
          </a:repeat>
          <a:assert name="test4b_property" value="good"/>
       </target>

       <target name="test5">
          <property name="call_count" value="0"/>
          <a:limit seconds="5" failonerror="true">
             <a:repeat count="-1" interval="1">
                <a:until>
                   <a:contains property="log_contents" substring="All tests passed 4 times." />
                </a:until>

                <echo>read log</echo>
                <a:new>
                   <a:call target="readLog"/>
                </a:new>
                <echo>${call_count} - ${log_contents}</echo>

             </a:repeat>
          </a:limit>
       </target>

       <target name="readLog">
          <a:unset name="log_contents"/>
          <a:new>
             <a:math result="call_count" operand1="${call_count}" operand2="1" operation="+" datatype="int"/>
             <property name="log_contents" value="All tests passed ${call_count} times."/>
          </a:new>
       </target>

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