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How to use EagerLetHook method of com.greghaskins.spectrum.internal.hooks.EagerLetHook class

Best Spectrum code snippet using com.greghaskins.spectrum.internal.hooks.EagerLetHook.EagerLetHook

Source:Specification.java

...9import com.greghaskins.spectrum.ThrowingSupplier;10import com.greghaskins.spectrum.internal.DeclarationState;11import com.greghaskins.spectrum.internal.Suite;12import com.greghaskins.spectrum.internal.blocks.IdempotentBlock;13import com.greghaskins.spectrum.internal.hooks.EagerLetHook;14import com.greghaskins.spectrum.internal.hooks.Hook;15import com.greghaskins.spectrum.internal.hooks.HookContext.AppliesTo;16import com.greghaskins.spectrum.internal.hooks.HookContext.Precedence;17import com.greghaskins.spectrum.internal.hooks.LetHook;18import org.junit.AssumptionViolatedException;19import java.util.function.Supplier;20public interface Specification {21  /**22   * Declare a test suite that describes the expected behavior of the system in a given context.23   *24   * @param context Description of the context for this suite25   * @param block   {@link Block} with one or more calls to {@link #it(String, Block) it} that26   *                define each expected behavior27   */28  static void describe(final String context, final Block block) {29    final Suite suite = DeclarationState.instance()30        .getCurrentSuiteBeingDeclared()31        .addSuite(context);32    suite.applyConfigurationFromBlock(block);33    DeclarationState.instance().beginDeclaration(suite, block);34  }35  /**36   * Focus on this specific suite, while ignoring others.37   *38   * @param context Description of the context for this suite39   * @param block   {@link Block} with one or more calls to {@link #it(String, Block) it} that40   *                define each expected behavior41   * @see #describe(String, Block)42   */43  static void fdescribe(final String context, final Block block) {44    describe(context, with(focus(), block));45  }46  /**47   * Ignore the specific suite.48   *49   * @param context Description of the context for this suite50   * @param block   {@link Block} with one or more calls to {@link #it(String, Block) it} that51   *                define each expected behavior52   * @see #describe(String, Block)53   */54  static void xdescribe(final String context, final Block block) {55    describe(context, with(ignore(), block));56  }57  /**58   * Declare a spec, or test, for an expected behavior of the system in this suite context.59   *60   * @param behavior Description of the expected behavior61   * @param block    {@link Block} that verifies the system behaves as expected and throws a {@link62   *                 java.lang.Throwable Throwable} if that expectation is not met.63   */64  static void it(final String behavior, final Block block) {65    DeclarationState.instance().getCurrentSuiteBeingDeclared().addSpec(behavior, block);66  }67  /**68   * Declare a pending spec (without a block) that will be ignored.69   *70   * @param behavior Description of the expected behavior71   * @see #xit(String, Block)72   */73  static void it(final String behavior) {74    DeclarationState.instance().getCurrentSuiteBeingDeclared().addSpec(behavior, null).ignore();75  }76  /**77   * Focus on this specific spec, while ignoring others.78   *79   * @param behavior Description of the expected behavior80   * @param block    {@link Block} that verifies the system behaves as expected and throws a {@link81   *                 java.lang.Throwable Throwable} if that expectation is not met.82   * @see #it(String, Block)83   */84  static void fit(final String behavior, final Block block) {85    it(behavior, with(focus(), block));86  }87  /**88   * Mark a spec as ignored so that it will be skipped.89   *90   * @param behavior Description of the expected behavior91   * @param block    {@link Block} that will not run, since this spec is ignored.92   * @see #it(String, Block)93   */94  static void xit(final String behavior, final Block block) {95    it(behavior);96  }97  /**98   * Declare a {@link Block} to be run before each spec in the suite.99   *100   * <p>101   * Use this to perform setup actions that are common across tests in the context. If multiple102   * {@code beforeEach} blocks are declared, they will run in declaration order.103   * </p>104   *105   * @param block {@link Block} to run once before each spec106   */107  static void beforeEach(final Block block) {108    DeclarationState.instance().addHook(before(block), AppliesTo.ATOMIC_ONLY, Precedence.LOCAL);109  }110  /**111   * Declare a {@link Block Block} to be run after each spec in the current suite.112   *113   * <p>114   * Use this to perform teardown or cleanup actions that are common across specs in this suite. If115   * multiple {@code afterEach} blocks are declared, they will run in declaration order.116   * </p>117   *118   * @param block {@link Block Block} to run once after each spec119   */120  static void afterEach(final Block block) {121    DeclarationState.instance().addHook(after(block), AppliesTo.ATOMIC_ONLY,122        Precedence.GUARANTEED_CLEAN_UP_LOCAL);123  }124  /**125   * Declare a {@link Block Block} to be run once before all the specs in the current suite begin.126   *127   * <p>128   * Use {@code beforeAll} and {@link #afterAll(Block) afterAll} blocks with caution: since they129   * only run once, shared state <strong>will</strong> leak across specs.130   * </p>131   *132   * @param block {@link Block} to run once before all specs in this suite133   */134  static void beforeAll(final Block block) {135    DeclarationState.instance().addHook(before(new IdempotentBlock(block)), AppliesTo.ATOMIC_ONLY,136        Precedence.SET_UP);137  }138  /**139   * Declare a {@link Block} to be run once after all the specs in the current suite have run.140   *141   * <p>142   * Use {@link #beforeAll(Block) beforeAll} and {@code afterAll} blocks with caution: since they143   * only run once, shared state <strong>will</strong> leak across tests.144   * </p>145   *146   * @param block {@link Block} to run once after all specs in this suite147   */148  static void afterAll(final Block block) {149    DeclarationState.instance().addHook(after(block), AppliesTo.ONCE,150        Precedence.GUARANTEED_CLEAN_UP_GLOBAL);151  }152  /**153   * A value that will be fresh within each spec and cannot bleed across specs.154   *155   * <p>156   * Note that {@code let} is lazy-evaluated: the {@code supplier} is not called until the first157   * time it is used.158   * </p>159   *160   * @param <T>      The type of value161   * @param supplier {@link ThrowingSupplier} function that either generates the value, or throws a162   *                 {@link Throwable}163   * @return supplier which is refreshed for each spec's context164   */165  static <T> Supplier<T> let(final ThrowingSupplier<T> supplier) {166    LetHook<T> letHook = new LetHook<>(supplier);167    DeclarationState.instance().addHook(letHook, AppliesTo.ATOMIC_ONLY, Precedence.LOCAL);168    return letHook;169  }170  /**171   * A value that will be calculated fresh at the start of each spec and cannot bleed across specs.172   *173   * <p>174   * Note that {@code eagerLet} is eagerly evaluated: the {@code supplier} is called at the start175   * of the spec, before {@code beforeEach} blocks.176   * </p>177   *178   * @param <T>      The type of value179   * @param supplier {@link ThrowingSupplier} function that either generates the value, or throws a180   *                 {@link Throwable}181   * @return supplier which is refreshed for each spec's context182   */183  static <T> Supplier<T> eagerLet(final ThrowingSupplier<T> supplier) {184    EagerLetHook<T> eagerLetHook = new EagerLetHook<>(supplier);185    DeclarationState.instance().addHook(eagerLetHook, AppliesTo.ATOMIC_ONLY, Precedence.LOCAL);186    return eagerLetHook;187  }188  /**189   * Define a test context. Alias for {@link #describe}.190   *191   * @param context the description of the context192   * @param block   the block to execute193   */194  static void context(final String context, final Block block) {195    describe(context, block);196  }197  /**198   * Define a focused test context. Alias for {@link #fdescribe}....

Source:EagerLetHook.java

...5 *6 * <p>Sematics are the same as with {@link LetHook}, except that all values are calculated at the7 * start of the test, rather than on an as-needed basis.8 */9public class EagerLetHook<T> extends AbstractSupplyingHook<T> {10  private final ThrowingSupplier<T> supplier;11  public EagerLetHook(final ThrowingSupplier<T> supplier) {12    this.supplier = supplier;13  }14  protected T before() {15    return supplier.get();16  }17  protected String getExceptionMessageIfUsedAtDeclarationTime() {18    return "Cannot use the value from eagerLet() in a suite declaration. "19        + "It may only be used in the context of a running spec.";20  }21}...

EagerLetHook

Using AI Code Generation

1package com.greghaskins.spectrum.internal.hooks;2import com.greghaskins.spectrum.Block;3import com.greghaskins.spectrum.internal.hooks.EagerLetHook;4public class EagerLetHookTest {5    public static void main(String[] args) {6        EagerLetHook hook = new EagerLetHook();7        hook.hook(new Block() {8            public void run() throws Throwable {9                System.out.println("Hello World!");10            }11        });12    }13}

EagerLetHook

Using AI Code Generation

1package com.greghaskins.spectrum;2import com.greghaskins.spectrum.internal.hooks.EagerLetHook;3import static com.greghaskins.spectrum.Spectrum.*;4public class Example1 {5    public static void main(String[] args) {6        describe("a suite of tests", () -> {7            let("a value", () -> 2, EagerLetHook.INSTANCE);8            it("can use the value", () -> {9                System.out.println("The value is " + let());10            });11        });12    }13}14package com.greghaskins.spectrum;15import com.greghaskins.spectrum.internal.hooks.EagerLetHook;16import static com.greghaskins.spectrum.Spectrum.*;17public class Example2 {18    public static void main(String[] args) {19        describe("a suite of tests", () -> {20            let("a value", () -> 2, EagerLetHook.INSTANCE);21            it("can use the value", () -> {22                System.out.println("The value is " + let());23            });24        });25    }26}27package com.greghaskins.spectrum;28import com.greghaskins.spectrum.internal.hooks.EagerLetHook;29import static com.greghaskins.spectrum.Spectrum.*;30public class Example3 {31    public static void main(String[] args) {32        describe("a suite of tests", () -> {33            let("a value", () -> 2, EagerLetHook.INSTANCE);34            it("can use the value", () -> {35                System.out.println("The value is " + let());36            });37        });38    }39}40package com.greghaskins.spectrum;41import com.greghaskins.spectrum.internal.hooks.EagerLetHook;42import static com.greghaskins.spectrum.Spectrum.*;43public class Example4 {44    public static void main(String[] args) {

EagerLetHook

Using AI Code Generation

1package com.greghaskins.spectrum;2import org.junit.runner.RunWith;3import com.greghaskins.spectrum.internal.hooks.EagerLetHook;4@RunWith(Spectrum.class)5public class 1 {6  {7    describe("EagerLetHook", () -> {8      EagerLetHook hook = new EagerLetHook();9      it("should be instantiated", () -> {10        expect(hook).not.toBeNull();11      });12    });13  }14}15package com.greghaskins.spectrum;16import org.junit.runner.RunWith;17import com.greghaskins.spectrum.internal.hooks.EagerLetHook;18@RunWith(Spectrum.class)19public class 2 {20  {21    describe("EagerLetHook", () -> {22      EagerLetHook hook = new EagerLetHook();23      it("should be instantiated", () -> {24        expect(hook).not.toBeNull();25      });26    });27  }28}29package com.greghaskins.spectrum;30import org.junit.runner.RunWith;31import com.greghaskins.spectrum.internal.hooks.EagerLetHook;32@RunWith(Spectrum.class)33public class 3 {34  {35    describe("EagerLetHook", () -> {36      EagerLetHook hook = new EagerLetHook();37      it("should be instantiated", () -> {38        expect(hook).not.toBeNull();39      });40    });41  }42}43package com.greghaskins.spectrum;44import org.junit.runner.RunWith;45import com.greghaskins.spectrum.internal.hooks.EagerLetHook;46@RunWith(Spectrum.class)47public class 4 {48  {49    describe("EagerLetHook", () -> {50      EagerLetHook hook = new EagerLetHook();51      it("should be instantiated", () -> {52        expect(hook).not.toBeNull();53      });54    });55  }56}

EagerLetHook

Using AI Code Generation

1package com.greghaskins.spectrum;2import com.greghaskins.spectrum.internal.hooks.EagerLetHook;3public class 1 {4    public static void main(String[] args) {5        Suite.describe("test", () -> {6            Suite.let("test", () -> {7                return "test";8            }, new EagerLetHook());9        });10    }11}12package com.greghaskins.spectrum;13import com.greghaskins.spectrum.internal.hooks.EagerLetHook;14public class 2 {15    public static void main(String[] args) {16        Suite.describe("test", () -> {17            Suite.let("test", () -> {18                return "test";19            }, new EagerLetHook());20        });21    }22}23package com.greghaskins.spectrum;24import com.greghaskins.spectrum.internal.hooks.EagerLetHook;25public class 3 {26    public static void main(String[] args) {27        Suite.describe("test", () -> {28            Suite.let("test", () -> {29                return "test";30            }, new EagerLetHook());31        });32    }33}34package com.greghaskins.spectrum;35import com.greghaskins.spectrum.internal.hooks.EagerLetHook;36public class 4 {37    public static void main(String[] args) {38        Suite.describe("test", () -> {39            Suite.let("test", () -> {40                return "test";41            }, new EagerLetHook());42        });43    }44}45package com.greghaskins.spectrum;46import com.greghaskins.spectrum.internal.hooks.EagerLetHook;47public class 5 {48    public static void main(String[] args) {49        Suite.describe("

EagerLetHook

Using AI Code Generation

1package com.greghaskins.spectrum;2import org.junit.runner.RunWith;3import static com.greghaskins.spectrum.Spectrum.*;4@RunWith(Spectrum.class)5public class 1 {6  public static void main(String[] args) {7    describe("Spectrum", () -> {8      describe("EagerLetHook", () -> {9        it("should be used by default", () -> {10        });11      });12    });13  }14}15package com.greghaskins.spectrum;16import org.junit.runner.RunWith;17import static com.greghaskins.spectrum.Spectrum.*;18@RunWith(Spectrum.class)19public class 2 {20  public static void main(String[] args) {21    describe("Spectrum", () -> {22      describe("EagerLetHook", () -> {23        it("should be used by default", () -> {24        });25      });26    });27  }28}29package com.greghaskins.spectrum;30import org.junit.runner.RunWith;31import static com.greghaskins.spectrum.Spectrum.*;32@RunWith(Spectrum.class)33public class 3 {34  public static void main(String[] args) {35    describe("Spectrum", () -> {36      describe("EagerLetHook", () -> {37        it("should be used by default", () -> {38        });39      });40    });41  }42}43package com.greghaskins.spectrum;44import org.junit.runner.RunWith;45import static com.greghaskins.spectrum.Spectrum.*;46@RunWith(Spectrum.class)47public class 4 {48  public static void main(String[] args) {49    describe("Spectrum", () ->

EagerLetHook

Using AI Code Generation

1import com.greghaskins.spectrum.Spectrum;2import com.greghaskins.spectrum.Spectrum.*;3import com.greghaskins.spectrum.*;4import static com.greghaskins.spectrum.Spectrum.*;5public class TestSpectrum {6    public static void main(String[] args) {7        describe("a test", () -> {8            beforeAll(() -> {9                System.out.println("beforeAll");10            });11            beforeEach(() -> {12                System.out.println("beforeEach");13            });14            it("should do something", () -> {15                System.out.println("it");16            });17            afterEach(() -> {18                System.out.println("afterEach");19            });20            afterAll(() -> {21                System.out.println("afterAll");22            });23        });24    }25}26import com.greghaskins.spectrum.Spectrum;27import com.greghaskins.spectrum.Spectrum.*;28import com.greghaskins.spectrum.*;29import static com.greghaskins.spectrum.Spectrum.*;30public class TestSpectrum {31    public static void main(String[] args) {32        describe("a test", () -> {33            beforeAll(() -> {34                System.out.println("beforeAll");35            });36            beforeEach(() -> {37                System.out.println("beforeEach");38            });39            it("should do something", () -> {40                System.out.println("it");41            });42            afterEach(() -> {43                System.out.println("afterEach");44            });45            afterAll(() -> {46                System.out.println("afterAll");47            });48        });49    }50}51import com.greghaskins.spectrum.Spectrum;52import com.greghaskins.spectrum.Spectrum.*;53import com.greghaskins.spectrum.*;54import static com.greghaskins.spectrum.Spectrum.*;55public class TestSpectrum {56    public static void main(String[] args) {57        describe("a test", () -> {58            beforeAll(() -> {59                System.out.println("beforeAll");60            });61            beforeEach(() -> {

EagerLetHook

Using AI Code Generation

1package com.greghaskins.spectrum;2import org.junit.runner.RunWith;3import com.greghaskins.spectrum.internal.hooks.EagerLetHook;4@RunWith(Spectrum.class)5public class TestEagerLetHook {6    {7        describe("a group", () -> {8            final int[] counter = {0};9            let("a value", () -> {10                counter[0]++;11                return counter[0];12            }, new EagerLetHook());13            it("should run the let once", () -> {14                expect(counter[0], is(1));15            });16            it("should run the let once", () -> {17                expect(counter[0], is(1));18            });19        });20    }21}22package com.greghaskins.spectrum;23import org.junit.runner.RunWith;24import com.greghaskins.spectrum.internal.hooks.EagerLetHook;25@RunWith(Spectrum.class)26public class TestEagerLetHook {27    {28        describe("a group", () -> {29            final int[] counter = {0};30            let("a value", () -> {31                counter[0]++;32                return counter[0];33            }, new EagerLetHook());34            it("should run the let once", () -> {35                expect(counter[0], is(1));36            });37            it("should run the let once", () -> {38                expect(counter[0], is(1));39            });40        });41    }42}43package com.greghaskins.spectrum;44import org.junit.runner.RunWith;45import com.greghaskins.spectrum.internal.hooks.EagerLetHook;46@RunWith(Spectrum.class)47public class TestEagerLetHook {48    {49        describe("a group", () -> {50            final int[] counter = {0};51            let("a value", () -> {52                counter[0]++;53                return counter[0];54            }, new EagerLetHook());55            it("should run the let once", () -> {56                expect(counter[0], is(1

EagerLetHook

Using AI Code Generation

1public class 1 {2    public static void main(String[] args) {3        EagerLetHook hook = new EagerLetHook();4        hook.applyTo(new Suite("Test Suite", () -> {5            describe("A suite", () -> {6                it("contains a spec with an expectation", () -> {7                    expect(1).toEqual(1);8                });9            });10        }));11    }12}13public class 2 {14    public static void main(String[] args) {15        EagerLetHook hook = new EagerLetHook();16        hook.applyTo(new Suite("Test Suite", () -> {17            describe("A suite", () -> {18                it("contains a spec with an expectation", () -> {19                    expect(1).toEqual(1);20                });21            });22        }));23    }24}25public class 3 {26    public static void main(String[] args) {27        EagerLetHook hook = new EagerLetHook();28        hook.applyTo(new Suite("Test Suite", () -> {29            describe("A suite", () -> {30                it("contains a spec with an expectation", () -> {31                    expect(1).toEqual(1);32                });33            });34        }));35    }36}37public class 4 {38    public static void main(String[] args) {39        EagerLetHook hook = new EagerLetHook();40        hook.applyTo(new Suite("Test Suite", () -> {41            describe("A suite", () -> {42                it("contains a spec with an expectation", () -> {43                    expect(1).toEqual(1);44                });45            });46        }));47    }48}49public class 5 {50    public static void main(String[] args) {51        EagerLetHook hook = new EagerLetHook();52        hook.applyTo(new Suite("Test Suite",

EagerLetHook

Using AI Code Generation

1package com.greghaskins.spectrum;2import org.junit.runner.RunWith;3@RunWith(Spectrum.class)4public class ExampleTest {5    {6        describe("a test", () -> {7            String value = let(() -> "value");8            it("has a value", () -> {9                System.out.println("value = " + value);10            });11        });12    }13}14package com.greghaskins.spectrum;15import org.junit.runner.RunWith;16@RunWith(Spectrum.class)17public class ExampleTest {18    {19        describe("a test", () -> {20            String value = let(() -> "value");21            it("has a value", () -> {22                System.out.println("value = " + value);23            });24        });25    }26}27package com.greghaskins.spectrum;28import org.junit.runner.RunWith;29@RunWith(Spectrum.class)30public class ExampleTest {31    {32        describe("a test", () -> {33            String value = let(() -> "value");34            it("has a value", () -> {35                System.out.println("value = " + value);36            });37        });38    }39}40package com.greghaskins.spectrum;41import org.junit.runner.RunWith;42@RunWith(Spectrum.class)43public class ExampleTest {44    {45        describe("a test", () -> {46            String value = let(() -> "value");47            it("has a value", () -> {48                System.out.println("value = " + value);49            });50        });51    }52}

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