transcendental-lisp/test/function/builtin/BackTickEvaluatorTester.java

package function.builtin;

import static sexpression.Nil.NIL;
import static testutil.TestUtilities.*;

import org.junit.Test;

import function.builtin.BackTickEvaluator.*;
import sexpression.*;

public class BackTickEvaluatorTester {

    private BackTickEvaluator createBackTickEvaluator(SExpression expression) {
        return new BackTickEvaluator(new BackTickExpression(expression));
    }

    @Test
    public void evaluateNil() {
        BackTickEvaluator evaluator = createBackTickEvaluator(NIL);

        assertSExpressionsMatch(NIL, evaluator.evaluate());
    }

    @Test
    public void evaluateNumber() {
        SExpression input = new LispNumber("99");
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        assertSExpressionsMatch(input, evaluator.evaluate());
    }

    @Test
    public void evaluateList() {
        SExpression input = makeList(new LispNumber("1"), new LispNumber("99"));
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        assertSExpressionsMatch(input, evaluator.evaluate());
    }

    @Test
    public void evaluateComma() {
        SExpression input = new CommaExpression(makeList(new Symbol("+"), new LispNumber("1"), new LispNumber("9")));
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        assertSExpressionsMatch(new LispNumber("10"), evaluator.evaluate());
    }

    @Test
    public void evaluateListWithComma() {
        SExpression input = makeList(new CommaExpression(makeList(new Symbol("+"), new LispNumber("1"),
                                                                  new LispNumber("9"))));
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        assertSExpressionsMatch(makeList(new LispNumber("10")), evaluator.evaluate());
    }

    @Test(expected = NestedCommaException.class)
    public void evaluateListWithNestedComma() {
        SExpression input = makeList(new CommaExpression(new CommaExpression(new Symbol("+"))));
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        evaluator.evaluate();
    }

    @Test(expected = AtSignNotInCommaException.class)
    public void evaluateListWithNoCommaPrecedingAtSign() {
        SExpression input = makeList(new AtSignExpression(makeList(new Symbol("+"))));
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        evaluator.evaluate();
    }

    @Test(expected = AtSignNotInCommaException.class)
    public void evaluateAtSign() {
        SExpression input = new AtSignExpression(makeList(new Symbol("+")));
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        evaluator.evaluate();
    }

    @Test(expected = NestedAtSignException.class)
    public void evaluateListWithNestedAtSigns() {
        SExpression input = makeList(new CommaExpression(new AtSignExpression(new AtSignExpression(makeList(new Symbol("+"))))));
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        evaluator.evaluate();
    }

    @Test(expected = NestedCommaException.class)
    public void evaluateListWithCommaAfterAtSign() {
        SExpression input = makeList(new CommaExpression(new AtSignExpression(new CommaExpression(makeList(new Symbol("+"))))));
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        evaluator.evaluate();
    }

    @Test
    public void evaluateListWithAtSign() {
        SExpression input = makeList(new CommaExpression(new AtSignExpression(makeList(new Symbol("LIST"),
                                                                                       new LispNumber("1"),
                                                                                       new LispNumber("9")))));
        SExpression expected = makeList(new LispNumber("1"), new LispNumber("9"));
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        assertSExpressionsMatch(expected, evaluator.evaluate());
    }

    @Test(expected = AtSignNotListException.class)
    public void atSignDoesNotEvaluateToList() {
        SExpression input = makeList(new CommaExpression(new AtSignExpression(new LispNumber("1"))));
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        evaluator.evaluate();
    }

    @Test
    public void evaluateListWithCommasAndAtSign() {
        SExpression input = makeList(new LispNumber("78"),
                                     new CommaExpression(new AtSignExpression(makeList(new Symbol("LIST"),
                                                                                       new LispNumber("1"),
                                                                                       new LispNumber("9")))),
                                     new CommaExpression(makeList(new Symbol("+"), new LispNumber("20"),
                                                                  new LispNumber("5"))),
                                     new CommaExpression(makeList(new Symbol("LIST"), new LispNumber("7"),
                                                                  new LispNumber("6"))),
                                     new LispString("\"sky\""));
        SExpression expected = makeList(new LispNumber("78"), new LispNumber("1"), new LispNumber("9"),
                                        new LispNumber("25"), makeList(new LispNumber("7"), new LispNumber("6")),
                                        new LispString("\"sky\""));
        BackTickEvaluator evaluator = createBackTickEvaluator(input);

        assertSExpressionsMatch(expected, evaluator.evaluate());
    }

}