trunk/src/testcases/org/apache/poi/ss/formula/functions/TestMid.java

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package org.apache.poi.ss.formula.functions;

import junit.framework.TestCase;

import org.apache.poi.ss.formula.eval.AreaEval;
import org.apache.poi.ss.formula.eval.BlankEval;
import org.apache.poi.ss.formula.eval.BoolEval;
import org.apache.poi.ss.formula.eval.ErrorEval;
import org.apache.poi.ss.formula.eval.NumberEval;
import org.apache.poi.ss.formula.eval.RefEval;
import org.apache.poi.ss.formula.eval.StringEval;
import org.apache.poi.ss.formula.eval.ValueEval;
/**
 * Tests for Excel function MID()
 *
 * @author Josh Micich
 */
public final class TestMid extends TestCase {


	private static ValueEval invokeMid(ValueEval text, ValueEval startPos, ValueEval numChars) {
		ValueEval[] args = new ValueEval[] { text, startPos, numChars, };
		return TextFunction.MID.evaluate(args, -1, (short)-1);
	}

	private void confirmMid(ValueEval text, ValueEval startPos, ValueEval numChars, String expected) {
		ValueEval result = invokeMid(text, startPos, numChars);
		assertEquals(StringEval.class, result.getClass());
		assertEquals(expected, ((StringEval)result).getStringValue());
	}

	private void confirmMid(ValueEval text, ValueEval startPos, ValueEval numChars, ErrorEval expectedError) {
		ValueEval result = invokeMid(text, startPos, numChars);
		assertEquals(ErrorEval.class, result.getClass());
		assertEquals(expectedError.getErrorCode(), ((ErrorEval)result).getErrorCode());
	}

	public void testBasic() {

		confirmMid(new StringEval("galactic"), new NumberEval(3), new NumberEval(4), "lact");
	}

	/**
	 * Valid cases where args are not precisely (string, int, int) but can be resolved OK.
	 */
	public void testUnusualArgs() {
		// startPos with fractional digits
		confirmMid(new StringEval("galactic"), new NumberEval(3.1), new NumberEval(4), "lact");

		// string startPos
		confirmMid(new StringEval("galactic"), new StringEval("3"), new NumberEval(4), "lact");

		// text (first) arg type is number, other args are strings with fractional digits
		confirmMid(new NumberEval(123456), new StringEval("3.1"), new StringEval("2.9"), "34");

		// startPos is 1x1 area ref, numChars is cell ref
		AreaEval aeStart = EvalFactory.createAreaEval("A1:A1", new ValueEval[] { new NumberEval(2), } );
		RefEval reNumChars = EvalFactory.createRefEval("B1", new NumberEval(3));
		confirmMid(new StringEval("galactic"), aeStart, reNumChars, "ala");

		confirmMid(new StringEval("galactic"), new NumberEval(3.1), BlankEval.instance, "");

		confirmMid(new StringEval("galactic"), new NumberEval(3), BoolEval.FALSE, "");
		confirmMid(new StringEval("galactic"), new NumberEval(3), BoolEval.TRUE, "l");
		confirmMid(BlankEval.instance, new NumberEval(3), BoolEval.TRUE, "");

	}

	/**
	 * Extreme values for startPos and numChars
	 */
	public void testExtremes() {
		confirmMid(new StringEval("galactic"), new NumberEval(4), new NumberEval(400), "actic");

		confirmMid(new StringEval("galactic"), new NumberEval(30), new NumberEval(4), "");
		confirmMid(new StringEval("galactic"), new NumberEval(3), new NumberEval(0), "");
	}

	/**
	 * All sorts of ways to make MID return defined errors.
	 */
	public void testErrors() {
		confirmMid(ErrorEval.NAME_INVALID, new NumberEval(3), new NumberEval(4), ErrorEval.NAME_INVALID);
		confirmMid(new StringEval("galactic"), ErrorEval.NAME_INVALID, new NumberEval(4), ErrorEval.NAME_INVALID);
		confirmMid(new StringEval("galactic"), new NumberEval(3), ErrorEval.NAME_INVALID, ErrorEval.NAME_INVALID);
		confirmMid(new StringEval("galactic"), ErrorEval.DIV_ZERO, ErrorEval.NAME_INVALID, ErrorEval.DIV_ZERO);

		confirmMid(new StringEval("galactic"), BlankEval.instance, new NumberEval(3.1), ErrorEval.VALUE_INVALID);

		confirmMid(new StringEval("galactic"), new NumberEval(0), new NumberEval(4), ErrorEval.VALUE_INVALID);
		confirmMid(new StringEval("galactic"), new NumberEval(1), new NumberEval(-1), ErrorEval.VALUE_INVALID);
	}
}