// Copyright 2022 Google LLC

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

// https://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

package codelab.solutions;

import static com.google.common.truth.Truth.assertThat;

import static org.junit.Assert.assertThrows;

import dev.cel.common.CelAbstractSyntaxTree;

import dev.cel.compiler.CelCompiler;

import dev.cel.compiler.CelCompilerFactory;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.junit.runners.JUnit4;

@RunWith(JUnit4.class)

public final class Exercise1Test {

private static final String TEST_EXPRESSION = "'Hello, World!'";

private final Exercise1 exercise1 = new Exercise1();

@Test

public void compile_stringExpression_parseSuccess() {

CelAbstractSyntaxTree ast = exercise1.compile(TEST_EXPRESSION);

assertThat(ast).isNotNull();

}

@Test

public void compile_stringExpression_typecheckSuccess() {

CelAbstractSyntaxTree ast = exercise1.compile(TEST_EXPRESSION);

assertThat(ast.isChecked()).isTrue();

}

@Test

public void compile_booleanExpression_throwsValidationException() {

IllegalArgumentException exception =

assertThrows(IllegalArgumentException.class, () -> exercise1.compile("true == true"));

assertThat(exception).hasMessageThat().contains("Failed to type-check expression.");

assertThat(exception).hasMessageThat().contains("expected type 'string' but found 'bool'");

}

@Test

public void evaluate_stringExpression_success() {

CelAbstractSyntaxTree ast = exercise1.compile(TEST_EXPRESSION);

Object evaluatedResult = exercise1.eval(ast);

assertThat(evaluatedResult).isEqualTo("Hello, World!");

}

@Test

public void evaluate_divideByZeroExpression_throwsEvaluationException() throws Exception {

CelCompiler compiler = CelCompilerFactory.standardCelCompilerBuilder().build();

CelAbstractSyntaxTree ast = compiler.compile("1/0").getAst();

IllegalArgumentException exception =

assertThrows(IllegalArgumentException.class, () -> exercise1.eval(ast));

assertThat(exception).hasMessageThat().contains("evaluation error at <input>:1: / by zero");

}

}