Introduce TestNG to JUnit migration module [DRAFT]

error-prone-contrib/pom.xml

@@ -202,7 +202,7 @@
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-engine</artifactId>
-            <scope>test</scope>
+            <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>

jitpack.yml

@@ -0,0 +1,9 @@
+before_install:
+  - mvn -version
+  - source "${HOME}/.sdkman/bin/sdkman-init.sh"
+  - sdk update
+  - sdk install java 21.0.7-tem
+  - sdk use java 21.0.7-tem
+  - sdk install maven 3.9.11
+  - sdk use maven 3.9.11
+  - mvn org.apache.maven.plugins:maven-wrapper-plugin:3.3.2:wrapper -Dmaven=3.9.11

pom.xml

@@ -48,6 +48,7 @@
         <module>refaster-runner</module>
         <module>refaster-support</module>
         <module>refaster-test-support</module>
+        <module>testng-junit-migrator</module>
     </modules>
 
     <scm child.scm.developerConnection.inherit.append.path="false" child.scm.url.inherit.append.path="false">

testng-junit-migrator/README.md

@@ -0,0 +1,147 @@
+# TestNG to JUnit Jupiter migrator
+
+This module contains a tool to automatically migrate TestNG tests to JUnit
+Jupiter. The tool is built on top of [Error Prone][error-prone-orig-repo]. To
+use it, read the installation guide below.
+
+### Installation
+
+1. First, follow Error Prone's [installation
+   guide][error-prone-installation-guide]. For extra information, see this
+   [README][eps-readme]. (This step can be skipped for Picnic repositories!)
+2. Clone the Error Prone Support repository and checkout the branch
+   `gdejong/testng-migrator`.
+3. Next, run `mvn versions:set -DnewVersion=0.17.1-testng-migration -DgenerateBackupPoms=false`.
+   This will update set the version to `0.17.1-testng-migration`.
+4. Next, run `mvn clean install`. This will create a `0.17.1-testng-migrator` version
+   of the `testng-junit-migrator` module. The version will now be available in your local Maven repository.
+5. Finally, add the following profile to your `pom.xml`. This should be the `pom.xml` in the root of your module. 
+   Usually this is the parent `pom.xml`, but single module projects are also supported.
+
+```xml
+<profiles>
+    <profile>
+        <id>testng-migrator</id>
+        <build>
+            <plugins>
+                <plugin>
+                    <groupId>org.apache.maven.plugins</groupId>
+                    <artifactId>maven-compiler-plugin</artifactId>
+                    <configuration>
+                        <annotationProcessorPaths combine.children="append">
+                            <path>
+                                <groupId>tech.picnic.error-prone-support</groupId>
+                                <artifactId>testng-junit-migrator</artifactId>
+                                <version>0.10.1-testng-migration</version>
+                            </path>
+                        </annotationProcessorPaths>
+                    </configuration>
+                </plugin>
+            </plugins>
+        </build>
+    </profile>
+</profiles>
+```
+
+Having this profile allows the migration script to verify the correctness of
+the result by making sure the same amount of tests are executed.
+
+## Run the migration
+
+> **Note**
+> For Picnic repositories there is an extra step required _before_ running the
+> migration, see [here](#picnic-specific).
+
+Now that the migration is set up, one can start the migration by executing the
+[run-testng-junit-migrator.sh][migration-script] script in the same directory as the `pom.xml` file we changed earlier.
+
+This script will:
+
+1. Add the required `JUnit` dependencies to your `pom.xml`.
+2. Run the `testng-to-junit` migration.
+
+> **Note**
+> Please verify that the migrated code still compiles after each step of the compilation.
+
+### Counting tests
+
+The amount of tests executed before the migration can be counted using the `--count` flag:
+```sh
+./run-testng-junit-migrator.sh --count
+```
+This will count the amount of tests that are executed. This is recommended before running the migration
+to allow for comparison.
+
+### Picnic specific
+
+The `PicnicSupermarket/picnic-scratch` repository contains a helper script
+`java-platform/testng-junit-migration.sh` that migrates some more
+Picnic-specific code. This should be executed _before_ starting the actual
+migration.
+
+> **Warning**
+> This is a warning for `macOs` users.
+> Make sure gnu-grep and gnu-sed are installed!
+>
+> ```brew install grep gnu-sed```
+
+Continue with performing the actual migration [here](#run-the-migration).
+Afterward, run the `./picnic-shared-tools/patch.sh` script.
+
+Now you are done! 🤘🚀
+
+### Migration code example
+
+Consider the following TestNG test class:
+
+```java
+// TestNG code:
+@Test
+public class A {
+  public void simpleTest() {}
+
+  @Test(priority = 2)
+  public void priorityTest() {}
+
+  @DataProvider
+  private static Object[][] dataProviderTestCases() {
+    return new Object[]{{1}, {2}, {3}};
+  }
+
+  @Test(dataProvider = "dataProviderTestCases")
+  public void dataProviderTest(int number) {}
+}
+```
+
+This migration tool will turn this into the following:
+
+```java
+// JUnit Jupiter code:
+@TestMethodOrder(MethodOrderer.OrderAnnotation.class)
+public class A {
+  @Test
+  void simpleTest() {}
+
+  @Test
+  @Order(2)
+  public void priorityTest() {}
+
+  private static Stream<Argument> dataProviderTestCases() {
+    return Stream.of(arguments(1), arguments(2), arguments(3));
+  }
+
+  @ParameterizedTest
+  @MethodSource("dataProviderTestCases")
+  public void dataProviderTest(int number) {}
+}
+```
+
+### Known limitations
+- Certain `@DataProvider` methods cannot be automatically migrated (e.g., `return Stream.of(...).toArray(Object[][]::new)`).
+- Some uncommon `@Test` attributes are not supported, such as `ignoreMissingDependencies` and `dependsOnMethods`.
+- Test setup and teardown methods `@{Before, After}Test` are migrated to `@{Before, After}Each` to avoid introducing breaking changes. `@{Before, After}All` require a static method, while `@{Before, After}Test` are instance methods.
+
+[eps-readme]: ../README.md
+[error-prone-installation-guide]: https://errorprone.info/docs/installation#maven
+[error-prone-orig-repo]: https://github.com/google/error-prone
+[migration-script]: run-testng-junit-migration.sh

testng-junit-migrator/pom.xml

@@ -0,0 +1,161 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>tech.picnic.error-prone-support</groupId>
+        <artifactId>error-prone-support</artifactId>
+        <version>0.24.1-SNAPSHOT</version>
+    </parent>
+
+    <artifactId>testng-junit-migrator</artifactId>
+
+    <name>Picnic :: Error Prone Support :: TestNG JUnit Migrator</name>
+    <description>A tool to migrate TestNG tests to JUnit</description>
+    <url>https://error-prone.picnic.tech</url>
+
+    <dependencies>
+        <dependency>
+            <groupId>${project.groupId}</groupId>
+            <artifactId>refaster-compiler</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>${project.groupId}</groupId>
+            <artifactId>refaster-support</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>${project.groupId}</groupId>
+            <artifactId>refaster-test-support</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.auto</groupId>
+            <artifactId>auto-common</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.google.auto.service</groupId>
+            <artifactId>auto-service-annotations</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.auto.value</groupId>
+            <artifactId>auto-value-annotations</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.errorprone</groupId>
+            <artifactId>error_prone_annotation</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.google.errorprone</groupId>
+            <artifactId>error_prone_annotations</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.errorprone</groupId>
+            <artifactId>error_prone_check_api</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.google.errorprone</groupId>
+            <artifactId>error_prone_test_helpers</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>javax.annotation</groupId>
+            <artifactId>javax.annotation-api</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>javax.inject</groupId>
+            <artifactId>javax.inject</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.jspecify</groupId>
+            <artifactId>jspecify</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-api</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-params</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.openrewrite</groupId>
+            <artifactId>rewrite-core</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.openrewrite</groupId>
+            <artifactId>rewrite-java</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.openrewrite</groupId>
+            <artifactId>rewrite-java-11</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.openrewrite</groupId>
+            <artifactId>rewrite-templating</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.openrewrite</groupId>
+            <artifactId>rewrite-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.testng</groupId>
+            <artifactId>testng</artifactId>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <pluginManagement>
+            <plugins>
+                <plugin>
+                    <groupId>org.apache.maven.plugins</groupId>
+                    <artifactId>maven-compiler-plugin</artifactId>
+                    <configuration>
+                        <annotationProcessorPaths combine.children="append">
+                            <path>
+                                <groupId>${project.groupId}</groupId>
+                                <artifactId>refaster-compiler</artifactId>
+                                <version>${project.version}</version>
+                            </path>
+                            <path>
+                                <groupId>${project.groupId}</groupId>
+                                <artifactId>refaster-support</artifactId>
+                                <version>${project.version}</version>
+                            </path>
+                        </annotationProcessorPaths>
+                        <compilerArgs combine.children="append">
+                            <arg>-Xplugin:RefasterRuleCompiler</arg>
+                        </compilerArgs>
+                    </configuration>
+                </plugin>
+            </plugins>
+        </pluginManagement>
+    </build>
+</project>