Easier Data Driven Tests for Java

build.gradle

@@ -124,18 +124,12 @@ nexusPublishing {
 subprojects { Project subproject ->
     if (subproject.name == 'guide') return
 
+    apply plugin: 'java-library'
     apply plugin: 'groovy'
 
     targetCompatibility = JavaVersion.VERSION_1_8
     sourceCompatibility = JavaVersion.VERSION_1_8
 
-    config {
-        bintray {
-            name = subproject.name
-            githubRepo = "agorapulse/$rootProject.name"
-        }
-    }
-
     test {
         systemProperty 'TEST_RESOURCES_FOLDER', new File(subproject.projectDir, 'src/test/resources').canonicalPath
         systemProperty 'user.timezone', 'UTC'

gradle.properties

@@ -23,5 +23,5 @@ kordampVersion=0.46.0
 nexusPluginVersion=1.0.0
 version = 0.2.0-SNAPSHOT
 groovyVersion = 2.5.4
-junitVersion = 4.13
+junitVersion = 5.10.2
 spockVersion = 1.3-groovy-2.5

libs/where4j/src/main/java/com/agorapulse/testing/where4j/Expectations.java

@@ -0,0 +1,23 @@
+package com.agorapulse.testing.where4j;
+
+import com.agorapulse.testing.where4j.dsl.*;
+import org.junit.jupiter.api.DynamicTest;
+
+import java.util.Arrays;
+
+public interface Expectations extends Iterable<DynamicTest> {
+
+    static Headers3 header(String nameA, String nameB, String nameC) {
+        return new Headers3(nameA, nameB, nameC);
+    }
+
+    static <A, B, C>Row3<A, B, C> row(A a, B b, C c) {
+        return new Row3<>(a, b, c);
+    }
+
+    @SafeVarargs
+    static <A, B, C> Where3<A, B, C> forEach(Headers3 headers, Row3<A, B, C> first, Row3<A, B, C> ... rest) {
+        return new Where3<>(headers, first, Arrays.asList(rest));
+    }
+
+}

libs/where4j/src/main/java/com/agorapulse/testing/where4j/dsl/Assertion3.java

@@ -0,0 +1,8 @@
+package com.agorapulse.testing.where4j.dsl;
+
+@FunctionalInterface
+public interface Assertion3<A, B, C> {
+
+    boolean verify(A a, B b, C c);
+
+}

libs/where4j/src/main/java/com/agorapulse/testing/where4j/dsl/Expectations3.java

@@ -0,0 +1,25 @@
+package com.agorapulse.testing.where4j.dsl;
+
+import com.agorapulse.testing.where4j.Expectations;
+import org.junit.jupiter.api.DynamicTest;
+
+import java.util.Iterator;
+
+class Expectations3<A, B, C> implements Expectations {
+
+    private final Where3<A, B, C> where;
+    private final String template;
+    private final Assertion3<A, B, C> verification;
+
+    Expectations3(Where3<A, B, C> where, String template, Assertion3<A, B, C> verification) {
+        this.where = where;
+        this.template = template;
+        this.verification = verification;
+    }
+
+    @Override
+    public Iterator<DynamicTest> iterator() {
+        return where.generateTests(template, verification);
+    }
+
+}

libs/where4j/src/main/java/com/agorapulse/testing/where4j/dsl/Headers3.java

@@ -0,0 +1,27 @@
+package com.agorapulse.testing.where4j.dsl;
+
+public class Headers3 {
+
+    private final String a;
+    private final String b;
+    private final String c;
+
+    public Headers3(String a, String b, String c) {
+        this.a = a;
+        this.b = b;
+        this.c = c;
+    }
+
+    public String getA() {
+        return a;
+    }
+
+    public String getB() {
+        return b;
+    }
+
+    public String getC() {
+        return c;
+    }
+
+}

libs/where4j/src/main/java/com/agorapulse/testing/where4j/dsl/Row3.java

@@ -0,0 +1,28 @@
+package com.agorapulse.testing.where4j.dsl;
+
+public class Row3<A, B, C> {
+
+    private final A a;
+    private final B b;
+    private final C c;
+
+    public Row3(A a, B b, C c) {
+        this.a = a;
+        this.b = b;
+        this.c = c;
+    }
+
+    public A getA() {
+        return a;
+    }
+
+    public B getB() {
+        return b;
+    }
+
+    public C getC() {
+        return c;
+    }
+
+
+}

libs/where4j/src/main/java/com/agorapulse/testing/where4j/dsl/Verifcation3.java

@@ -0,0 +1,8 @@
+package com.agorapulse.testing.where4j.dsl;
+
+@FunctionalInterface
+public interface Verifcation3<A, B, C> {
+
+    void verify(A a, B b, C c);
+
+}

libs/where4j/src/main/java/com/agorapulse/testing/where4j/dsl/Where3.java

@@ -0,0 +1,51 @@
+package com.agorapulse.testing.where4j.dsl;
+
+import com.agorapulse.testing.where4j.Expectations;
+import org.junit.jupiter.api.DynamicTest;
+import org.opentest4j.AssertionFailedError;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.List;
+
+public class Where3<A, B , C> {
+
+    private final List<Row3<A, B, C>> data = new ArrayList<>();
+    private final Headers3 headers;
+
+    public Where3(Headers3 headers, Row3<A, B, C> first, Collection<Row3<A, B, C>> rest) {
+        this.headers = headers;
+
+        this.data.add(first);
+        this.data.addAll(rest);
+    }
+
+    public Expectations expect(String template, Assertion3<A, B, C> verification) {
+        return new Expectations3<>(this, template, verification);
+    }
+
+    public Expectations verify(String template, Verifcation3<A, B, C> verification) {
+        return new Expectations3<>(this, template, (a, b, c) -> {
+            verification.verify(a, b, c);
+            return true;
+        });
+    }
+
+    Iterator<DynamicTest> generateTests(String template, Assertion3<A, B, C> verification) {
+        return data.stream().map(row -> {
+            String title = template.replace("#" + headers.getA(), String.valueOf(row.getA()));
+            title = title.replace("#" + headers.getB(), String.valueOf(row.getB()));
+            title = title.replace("#" + headers.getC(), String.valueOf(row.getC()));
+            String finalTitle = title;
+            return DynamicTest.dynamicTest(
+                finalTitle,
+                () -> {
+                    if (!verification.verify(row.getA(), row.getB(), row.getC())) {
+                        throw new AssertionFailedError("Verification failed for " + finalTitle + " with values " + headers.getA() + "=" + row.getA() + ", " + headers.getB() + "=" + row.getB() + ", " + headers.getC() + "=" + row.getC());
+                    }
+                }
+            );
+        }).iterator();
+    }
+}

libs/where4j/src/test/java/com/agorapulse/testing/where4j/Calculator.java

@@ -0,0 +1,13 @@
+package com.agorapulse.testing.where4j;
+
+public class Calculator {
+
+    public int add(int a, int b) {
+        return a + b;
+    }
+
+    public int subtract(int a, int b) {
+        return a - b;
+    }
+
+}

libs/where4j/src/test/java/com/agorapulse/testing/where4j/ExpectationsTest.java

@@ -0,0 +1,54 @@
+package com.agorapulse.testing.where4j;
+
+import org.junit.jupiter.api.TestFactory;
+
+import static com.agorapulse.testing.where4j.Expectations.*;
+import static org.junit.jupiter.api.Assertions.*;
+
+class ExpectationsTest {
+
+    @TestFactory
+    Expectations basicTestWithThreeVariablesAndExplicitEvaluation() {
+        Calculator calculator = new Calculator();
+
+        return forEach(
+            header("a", "b", "c"),
+            row(2, 3, 5),
+            row(3, 5, 8),
+            row(4, 7, 11)
+        ).expect("#a + #b = #c", (a, b, c) ->
+            calculator.add(a, b) == c
+        );
+    }
+
+    @TestFactory
+    Expectations basicTestWithThreeVariablesAndExplicitEvaluationWithMultipleLines() {
+        Calculator calculator = new Calculator();
+
+        return forEach(
+            header("a", "b", "c"),
+            row(2, 3, 5),
+            row(3, 5, 8),
+            row(4, 7, 11)
+        ).expect("#a + #b = #c", (a, b, c) ->
+            calculator.add(a, b) == c
+            && calculator.subtract(c, a) == b
+            && calculator.subtract(c, b) == a
+        );
+    }
+
+    @TestFactory
+    Expectations basicTestWithThreeVariablesAndAssertion() {
+        Calculator calculator = new Calculator();
+
+        return forEach(
+            header("a", "b", "c"),
+            row(2, 3, 5),
+            row(3, 5, 8),
+            row(4, 7, 11)
+        ).verify("#a + #b = #c", (a, b, c) ->
+            assertEquals(c, calculator.add(a, b))
+        );
+    }
+
+}

libs/where4j/where4j.gradle

@@ -0,0 +1,33 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Copyright 2018-2021 Agorapulse.
+ *
+ * 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.
+ */
+config {
+    publishing {
+        enabled = true
+    }
+}
+
+dependencies {
+    api "org.junit.jupiter:junit-jupiter-api:$junitVersion"
+
+    testRuntimeOnly "org.junit.jupiter:junit-jupiter-engine:$junitVersion"
+    testRuntimeOnly "org.junit.vintage:junit-vintage-engine:$junitVersion"
+}
+
+test {
+    useJUnitPlatform()
+}