Assertions.java

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package com.github.valid8j.classic;
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import com.github.valid8j.pcond.validator.Validator;
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import java.util.function.Predicate;
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/**
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 * // @formatter:off
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 * Use methods in this class with the ```assert``` statement.
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 *
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 * [source, java]
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 * ----
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 * import static com.github.valid8j.pcond.core.functions.Predicates.isNotNull;
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 * import static com.github.valid8j.pcond.classic.Assertions.*
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 *
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 * public class TestClass {
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 *   public static void aMethod(Object value) {
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 *     assert that(value, isNotNull());
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 *   }
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 * }
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 * ----
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 *
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 * This prints a much more readable error message than one you see for a usual assertion failure.
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 *
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 * ----
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 * Exception in thread "main" java.lang.AssertionError: Value:null violated: isNotNull
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 * null -> isNotNull -> false
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 * 	at com.github.valid8j.pcond.provider.impls.DefaultAssertionProvider.checkValue(DefaultAssertionProvider.java:70)
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 * 	at com.github.valid8j.pcond.provider.AssertionProviderBase.checkInvariant(AssertionProviderBase.java:78)
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 * 	at com.github.valid8j.pcond.classic.Assertions.that(Assertions.java:51)
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 * 	...
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 * ----
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 *
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 * To enable this feature, do not forget giving ```-ea``` VM option to enable assertions.
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 * Otherwise, the evaluation doesn't happen completely and even printable predicates constructed the right side of the `assert` statement.
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 * This means you can enable the feature during the development and disable it in the production so that you will not see no performance impact.
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 *
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 * // @formatter:on
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 *
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 */
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public enum Assertions {
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  ;
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  /**
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   * A method to be used for checking a value satisfies a given invariant condition.
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   * This method is intended to be used in `assert` statements.
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   *
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   * [source,java]
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   * .Example
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   * ----
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   * public void aMethod(String var) {
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   * assert that(var, isNotNull());
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   * }
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   * ----
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   *
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   * @param value     A value to be checked.
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   * @param predicate An invariant condition to check the {@code value}.
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   * @param <T>       The type of {@code value}.
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   * @return {@code true}, if the condition given as {@code predicate} is satisfied.
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   */
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  public static <T> boolean that(T value, Predicate<? super T> predicate) {
61 1 1. that : removed call to com/github/valid8j/pcond/validator/Validator::checkInvariant → KILLED
 
    Validator.instance().checkInvariant(value, predicate);
62 2 1. that : replaced boolean return with true for com/github/valid8j/classic/Assertions::that → SURVIVED
2. that : replaced boolean return with false for com/github/valid8j/classic/Assertions::that → KILLED
 
    return trueValue();
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  }
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  /**
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   * A method to be used for checking a value satisfies a given pre-condition.
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   * This method is intended to be used in `assert` statements.
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   *
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   * [source,java]
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   * .Example
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   * ----
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   * public void aMethod(String var) {
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   * assert precondition(var, isNotNull());
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   * }
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   * ----
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   *
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   * @param value     A value to be checked.
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   * @param predicate A pre-condition to check the {@code value}.
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   * @param <T>       The type of {@code value}.
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   * @return {@code true}, if the condition given as {@code predicate} is satisfied.
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   */
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  public static <T> boolean precondition(T value, Predicate<? super T> predicate) {
83 1 1. precondition : removed call to com/github/valid8j/pcond/validator/Validator::checkPrecondition → KILLED
 
    Validator.instance().checkPrecondition(value, predicate);
84 2 1. precondition : replaced boolean return with true for com/github/valid8j/classic/Assertions::precondition → SURVIVED
2. precondition : replaced boolean return with false for com/github/valid8j/classic/Assertions::precondition → KILLED
 
    return trueValue();
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  }
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  /**
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   * A method to be used for checking a value satisfies a given post-condition.
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   * This method is intended to be used in `assert` statements.
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   *
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   * [source,java]
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   * .Example
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   * ----
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   * public void aMethod(String var) {
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   * assert postcondition(var, isNotNull());
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   * }
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   * ----
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   *
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   * @param value     A value to be checked.
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   * @param predicate A post-condition to check the {@code value}.
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   * @param <T>       The type of {@code value}.
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   * @return {@code true}, if the condition given as {@code predicate} is satisfied.
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   */
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  public static <T> boolean postcondition(T value, Predicate<? super T> predicate) {
105 1 1. postcondition : removed call to com/github/valid8j/pcond/validator/Validator::checkPostcondition → KILLED
 
    Validator.instance().checkPostcondition(value, predicate);
106 2 1. postcondition : replaced boolean return with true for com/github/valid8j/classic/Assertions::postcondition → SURVIVED
2. postcondition : replaced boolean return with false for com/github/valid8j/classic/Assertions::postcondition → KILLED
 
    return trueValue();
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  }
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  /**
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   * This method always return {@code true}.
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   * This method is defined in order not to let an IDE report a warning
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   * Condition 'that(methodType, Predicates.isNotNull())' is always 'true'
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   * for caller codes of methods in this class.
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   *
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   * @return {@code true}
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   */
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  @SuppressWarnings("ConstantConditions")
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  private static boolean trueValue() {
119 2 1. trueValue : replaced boolean return with true for com/github/valid8j/classic/Assertions::trueValue → SURVIVED
2. trueValue : negated conditional → KILLED
 
    return Assertions.class != null;
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  }
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}

Mutations

61

1.1
Location : that
Killed by : com.github.valid8j.examples.test.ExamplesTest.testFluentExample(com.github.valid8j.examples.test.ExamplesTest) removed call to com/github/valid8j/pcond/validator/Validator::checkInvariant → KILLED
62

1.1
Location : that
Killed by : com.github.valid8j.ut.styles.FluentStyleDbCTest$ForEnsuresTest.test_that(com.github.valid8j.ut.styles.FluentStyleDbCTest$ForEnsuresTest) replaced boolean return with false for com/github/valid8j/classic/Assertions::that → KILLED

2.2
Location : that
Killed by : none replaced boolean return with true for com/github/valid8j/classic/Assertions::that → SURVIVED
83

1.1
Location : precondition
Killed by : com.github.valid8j.entrypoints.AssertionsTest$Failing removed call to com/github/valid8j/pcond/validator/Validator::checkPrecondition → KILLED
84

1.1
Location : precondition
Killed by : com.github.valid8j.ut.styles.FluentStyleDbCTest$ForEnsuresTest.test_precondition(com.github.valid8j.ut.styles.FluentStyleDbCTest$ForEnsuresTest) replaced boolean return with false for com/github/valid8j/classic/Assertions::precondition → KILLED

2.2
Location : precondition
Killed by : none replaced boolean return with true for com/github/valid8j/classic/Assertions::precondition → SURVIVED
105

1.1
Location : postcondition
Killed by : com.github.valid8j.entrypoints.AssertionsTest$Failing removed call to com/github/valid8j/pcond/validator/Validator::checkPostcondition → KILLED
106

1.1
Location : postcondition
Killed by : com.github.valid8j.ut.styles.FluentStyleDbCTest$ForEnsuresTest.test_postcondition(com.github.valid8j.ut.styles.FluentStyleDbCTest$ForEnsuresTest) replaced boolean return with false for com/github/valid8j/classic/Assertions::postcondition → KILLED

2.2
Location : postcondition
Killed by : none replaced boolean return with true for com/github/valid8j/classic/Assertions::postcondition → SURVIVED
119

1.1
Location : trueValue
Killed by : com.github.valid8j.ut.styles.FluentStyleDbCTest$ForEnsuresTest.test_postcondition(com.github.valid8j.ut.styles.FluentStyleDbCTest$ForEnsuresTest) negated conditional → KILLED

2.2
Location : trueValue
Killed by : none replaced boolean return with true for com/github/valid8j/classic/Assertions::trueValue → SURVIVED

Active mutators

Tests examined


Report generated by PIT 1.7.3