Merge pull request #23 from tricktron/f-minimal-frege-repl

New Simpler Repl Task

12 files changed, 1292 insertions, 556 deletions

diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/CompileFregeTaskFunctionalTest.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/CompileFregeTaskFunctionalTest.java
new file mode 100644
index 0000000..90a459c
--- /dev/null
+++ b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/CompileFregeTaskFunctionalTest.java
@@ -0,0 +1,408 @@
+package ch.fhnw.thga.gradleplugins;
+
+import static ch.fhnw.thga.gradleplugins.FregeExtension.DEFAULT_RELATIVE_SOURCE_DIR;
+import static ch.fhnw.thga.gradleplugins.FregePlugin.COMPILE_FREGE_TASK_NAME;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.createFregeSection;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.runAndFailGradleTask;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.runGradleTask;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.NEW_LINE;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.MINIMAL_BUILD_FILE_CONFIG;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.COMPLETION_FR;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.assertFileExists;
+import static org.gradle.testkit.runner.TaskOutcome.FAILED;
+import static org.gradle.testkit.runner.TaskOutcome.FROM_CACHE;
+import static org.gradle.testkit.runner.TaskOutcome.SUCCESS;
+import static org.gradle.testkit.runner.TaskOutcome.UP_TO_DATE;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.File;
+import java.util.stream.Stream;
+
+import org.gradle.api.Project;
+import org.gradle.testkit.runner.BuildResult;
+import org.junit.jupiter.api.DisplayNameGenerator;
+import org.junit.jupiter.api.IndicativeSentencesGeneration;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import ch.fhnw.thga.gradleplugins.fregeproject.FregeProjectBuilder;
+import ch.fhnw.thga.gradleplugins.fregeproject.FregeSourceFile;
+
+public class CompileFregeTaskFunctionalTest
+{
+    @Nested
+    @IndicativeSentencesGeneration(
+        separator = " -> ",
+        generator = DisplayNameGenerator.ReplaceUnderscores.class
+    )
+    class Compile_frege_task_works {
+
+        @Test
+        void given_frege_code_in_default_source_dir_and_minimal_build_file_config(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(MINIMAL_BUILD_FILE_CONFIG)
+                .fregeSourceFiles(() -> Stream.of(COMPLETION_FR))
+                .build();
+            
+            BuildResult result = runGradleTask(testProjectDir, COMPILE_FREGE_TASK_NAME);
+
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(COMPILE_FREGE_TASK_NAME) 
+                instanceof CompileFregeTask
+            );
+            assertEquals(
+                SUCCESS,
+                result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome()
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Completion.java"
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Completion.class"
+            );
+        }
+        @Test
+        void given_frege_code_and_many_compiler_flags(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            String buildConfigWithCompilerFlags = createFregeSection(
+                FregeDTOBuilder
+                .builder()
+                .version("'3.25.84'")
+                .release("'3.25alpha'")
+                .compilerFlags("['-v', '-make', '-O', '-hints']")
+                .build()
+            );
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(buildConfigWithCompilerFlags)
+                .fregeSourceFiles(() -> Stream.of(COMPLETION_FR))
+                .build();
+            
+            BuildResult result = runGradleTask(testProjectDir, COMPILE_FREGE_TASK_NAME);
+
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(COMPILE_FREGE_TASK_NAME) 
+                instanceof CompileFregeTask
+            );
+            assertEquals(
+                SUCCESS,
+                result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome()
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Completion.java"
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Completion.class"
+            );
+        }
+        @Test
+        void given_frege_code_in_custom_source_and_output_dir_and_minimal_build_file_config(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            String customSourceAndOutputBuildFileConfig = createFregeSection(
+                FregeDTOBuilder
+                .builder()
+                .version("'3.25.84'")
+                .release("'3.25alpha'")
+                .mainSourceDir("layout.projectDirectory.dir('src/frege')")
+                .outputDir("layout.buildDirectory.dir('frege')")
+                .build()
+            );
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(customSourceAndOutputBuildFileConfig)
+                .fregeSourceFiles(() -> Stream.of(new FregeSourceFile(
+                    "src/frege/ch/fhnw/thga/Completion.fr",
+                    COMPLETION_FR.getFregeSourceCode())))
+                .build();
+
+            BuildResult result = runGradleTask(testProjectDir, COMPILE_FREGE_TASK_NAME);
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(COMPILE_FREGE_TASK_NAME)
+                instanceof CompileFregeTask
+            );
+            assertEquals(
+                SUCCESS,
+                result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome()
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/frege/ch/fhnw/thga/Completion.java"
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/frege/ch/fhnw/thga/Completion.class"
+            );
+        }
+        @Test
+        void and_is_up_to_date_given_no_code_changes(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(MINIMAL_BUILD_FILE_CONFIG)
+                .fregeSourceFiles(() -> Stream.of(COMPLETION_FR))
+                .build();
+            
+            BuildResult first = runGradleTask(testProjectDir, COMPILE_FREGE_TASK_NAME);
+            
+            assertEquals(
+                SUCCESS, 
+                first.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
+
+            BuildResult second = runGradleTask(testProjectDir, COMPILE_FREGE_TASK_NAME);
+            
+            assertEquals(
+                UP_TO_DATE,
+                second.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
+        }
+        @Test
+        void and_is_cached_given_cache_hit(
+            @TempDir File testProjectDir) 
+            throws Exception 
+        {
+            FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(MINIMAL_BUILD_FILE_CONFIG)
+                .fregeSourceFiles(() -> Stream.of(COMPLETION_FR))
+                .build();
+
+            BuildResult first = runGradleTask(
+                testProjectDir,
+                COMPILE_FREGE_TASK_NAME,
+                "--build-cache"
+            );
+            
+            assertEquals(
+                SUCCESS, 
+                first.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome()
+            );
+
+            String codeChange = String.join(
+                NEW_LINE, 
+                "module ch.fhnw.thga.Completion where",
+                NEW_LINE,
+                NEW_LINE,
+                "  frob :: Int -> (Int, String)",
+                NEW_LINE,
+                "  frob i = (i, \"Frege rocks\")",
+                NEW_LINE
+            );
+            FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(MINIMAL_BUILD_FILE_CONFIG)
+                .fregeSourceFiles(() -> Stream.of(new FregeSourceFile(
+                    COMPLETION_FR.getFregeModulePath(),
+                    codeChange)))
+                .build();
+
+            BuildResult second = runGradleTask(
+                testProjectDir,
+                COMPILE_FREGE_TASK_NAME,
+                "--build-cache"
+            );
+            
+            assertEquals(
+                SUCCESS,
+                second.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome()
+            );
+
+            FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(MINIMAL_BUILD_FILE_CONFIG)
+                .fregeSourceFiles(() -> Stream.of(COMPLETION_FR))
+                .build();
+            BuildResult third = runGradleTask(
+                testProjectDir,
+                COMPILE_FREGE_TASK_NAME,
+                "--build-cache"
+            );
+            
+            assertEquals(
+                FROM_CACHE, 
+                third.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
+        }
+        @Test
+        void given_two_dependent_frege_files_in_default_source_dir_and_minimal_build_file_config(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            String frobCode = String.join(
+                NEW_LINE,
+                "module ch.fhnw.thga.Frob where",
+                NEW_LINE,
+                NEW_LINE,
+                "import ch.fhnw.thga.Completion (complete)",
+                NEW_LINE,
+                "frob i = complete $ i + i",
+                NEW_LINE
+            );
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(MINIMAL_BUILD_FILE_CONFIG)
+                .fregeSourceFiles(() -> Stream.of(COMPLETION_FR, new FregeSourceFile(
+                    String.format(
+                        "%s/%s",
+                        DEFAULT_RELATIVE_SOURCE_DIR,
+                        "ch/fhnw/thga/Frob.fr"
+                    ),
+                    frobCode)))
+                .build();
+            
+            BuildResult result = runGradleTask(
+                testProjectDir,
+                COMPILE_FREGE_TASK_NAME,
+                "--compileItem=ch.fhnw.thga.Frob"
+            );
+
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(COMPILE_FREGE_TASK_NAME) 
+                instanceof CompileFregeTask
+            );
+            assertEquals(
+                SUCCESS,
+                result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome()
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Completion.java"
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Completion.class"
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Frob.java"
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Frob.class"
+            );
+        }
+    }
+    @Nested
+    @IndicativeSentencesGeneration(
+        separator = " -> ",
+        generator = DisplayNameGenerator.ReplaceUnderscores.class
+    )
+    class Compile_frege_task_fails
+    {
+        @Test
+        void given_frege_code_and_illegal_compiler_flags(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            String buildConfigWithIllegalCompilerFlags = createFregeSection(
+                FregeDTOBuilder
+                .builder()
+                .version("'3.25.84'")
+                .release("'3.25alpha'")
+                .compilerFlags("['-make', '-bla']")
+                .build()
+            );
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(buildConfigWithIllegalCompilerFlags)
+                .fregeSourceFiles(() -> Stream.of(COMPLETION_FR))
+                .build();
+
+            BuildResult result = runAndFailGradleTask(testProjectDir, COMPILE_FREGE_TASK_NAME);
+
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(COMPILE_FREGE_TASK_NAME)
+                instanceof CompileFregeTask
+            );
+            assertEquals(
+                FAILED, 
+                result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome()
+            );
+        }
+        @Test
+        void given_two_dependent_frege_files_in_default_source_dir_and_without_make_compiler_flag(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            String frobCode = String.join(
+            NEW_LINE,
+            "module ch.fhnw.thga.Frob where",
+            NEW_LINE,
+            NEW_LINE,
+            "import ch.fhnw.thga.Completion (complete)",
+            NEW_LINE,
+            "frob i = complete $ i + i",
+            NEW_LINE
+            );
+            String minimalBuildFileConfigWithoutMake = createFregeSection(
+                FregeDTOBuilder
+                .builder()
+                .version("'3.25.84'")
+                .release("'3.25alpha'")
+                .compilerFlags("['-v']")
+                .build()
+            );
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(minimalBuildFileConfigWithoutMake)
+                .fregeSourceFiles(() -> Stream.of(COMPLETION_FR, new FregeSourceFile(
+                    String.format(
+                        "%s/%s",
+                        DEFAULT_RELATIVE_SOURCE_DIR,
+                        "ch/fhnw/thga/Frob.fr"
+                    ),
+                    frobCode)))
+                .build();
+            
+            BuildResult result = runAndFailGradleTask(
+                testProjectDir,
+                COMPILE_FREGE_TASK_NAME,
+                "--compileItem=ch.fhnw.thga.Frob"
+            );
+
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(COMPILE_FREGE_TASK_NAME) 
+                instanceof CompileFregeTask
+            );
+            assertEquals(
+                FAILED, 
+                result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome()
+            );
+        }
+    }
+}
diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/FregePluginFunctionalTest.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/FregePluginFunctionalTest.java
deleted file mode 100644
index a7c2b35..0000000
--- a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/FregePluginFunctionalTest.java
+++ /dev/null
@@ -1,556 +0,0 @@
-package ch.fhnw.thga.gradleplugins;
-
-import static ch.fhnw.thga.gradleplugins.FregeExtension.DEFAULT_DOWNLOAD_DIRECTORY;
-import static ch.fhnw.thga.gradleplugins.FregePlugin.COMPILE_FREGE_TASK_NAME;
-import static ch.fhnw.thga.gradleplugins.FregePlugin.DEPS_FREGE_TASK_NAME;
-import static ch.fhnw.thga.gradleplugins.FregePlugin.FREGE_EXTENSION_NAME;
-import static ch.fhnw.thga.gradleplugins.FregePlugin.FREGE_PLUGIN_ID;
-import static ch.fhnw.thga.gradleplugins.FregePlugin.REPL_FREGE_TASK_NAME;
-import static ch.fhnw.thga.gradleplugins.FregePlugin.RUN_FREGE_TASK_NAME;
-import static ch.fhnw.thga.gradleplugins.FregePlugin.SETUP_FREGE_TASK_NAME;
-import static ch.fhnw.thga.gradleplugins.GradleBuildFileConversionTest.createPluginsSection;
-import static org.gradle.testkit.runner.TaskOutcome.FAILED;
-import static org.gradle.testkit.runner.TaskOutcome.FROM_CACHE;
-import static org.gradle.testkit.runner.TaskOutcome.SUCCESS;
-import static org.gradle.testkit.runner.TaskOutcome.UP_TO_DATE;
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
-import java.io.BufferedWriter;
-import java.io.File;
-import java.io.FileWriter;
-import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.nio.file.Paths;
-import java.util.stream.Stream;
-
-import org.gradle.api.Project;
-import org.gradle.testfixtures.ProjectBuilder;
-import org.gradle.testkit.runner.BuildResult;
-import org.gradle.testkit.runner.GradleRunner;
-import org.junit.jupiter.api.AfterEach;
-import org.junit.jupiter.api.BeforeAll;
-import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.DisplayNameGenerator;
-import org.junit.jupiter.api.IndicativeSentencesGeneration;
-import org.junit.jupiter.api.Nested;
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.TestInstance;
-import org.junit.jupiter.api.TestInstance.Lifecycle;
-import org.junit.jupiter.api.io.TempDir;
-
-import ch.fhnw.thga.gradleplugins.internal.DependencyFregeTask;
-
-@TestInstance(Lifecycle.PER_CLASS)
-public class FregePluginFunctionalTest {
-    private static final String NEW_LINE = System.lineSeparator();
-    private static final String SIMPLE_FREGE_CODE = String.join(NEW_LINE, "module ch.fhnw.thga.Completion where",
-                    NEW_LINE, NEW_LINE, "  complete :: Int -> (Int, String)", NEW_LINE,
-                    "  complete i = (i, \"Frege rocks\")",
-                    NEW_LINE);
-
-    private static FregeDTOBuilder fregeBuilder;
-
-    @TempDir
-    File testProjectDir;
-    private File buildFile;
-    private File settingsFile;
-    private Project project;
-
-    private void writeFile(File destination, String content, boolean append) throws IOException {
-            try (BufferedWriter output = new BufferedWriter(new FileWriter(destination, append))) {
-                    output.write(content);
-            }
-    }
-
-    private void writeToFile(File destination, String content) throws IOException {
-            writeFile(destination, content, false);
-    }
-
-    private void appendToFile(File destination, String content) throws IOException {
-            writeFile(destination, System.lineSeparator() + content, true);
-    }
-
-    private static String createFregeSection(FregeDTO fregeDTO) {
-            return String.format(
-                "%s {%s  %s%s}",
-                FREGE_EXTENSION_NAME,
-                System.lineSeparator(),
-                fregeDTO.toBuildFile(),
-                System.lineSeparator());
-    }
-
-    private BuildResult runGradleTask(String... taskName) {
-            return GradleRunner.create().withProjectDir(testProjectDir).withPluginClasspath()
-                            .withArguments(taskName)
-                            .build();
-    }
-
-    private BuildResult runAndFailGradleTask(String taskName, String... args) {
-            return GradleRunner.create().withProjectDir(testProjectDir).withPluginClasspath()
-                            .withArguments(taskName)
-                            .buildAndFail();
-    }
-
-    private void setupDefaultFregeProjectStructure(String fregeCode, String fregeFileName, String buildFileConfig)
-                    throws Exception {
-            Files.createDirectories(testProjectDir.toPath().resolve(Paths.get("src", "main", "frege")));
-            File fregeFile = testProjectDir.toPath().resolve(Paths.get("src", "main", "frege", fregeFileName))
-                            .toFile();
-            writeToFile(fregeFile, fregeCode);
-            appendToFile(buildFile, buildFileConfig);
-    }
-
-    @BeforeAll
-    void beforeAll() throws Exception {
-            settingsFile = new File(testProjectDir, "settings.gradle");
-            writeToFile(settingsFile, "rootProject.name='frege-plugin'");
-            project = ProjectBuilder.builder().withProjectDir(testProjectDir).build();
-            project.getPluginManager().apply(FREGE_PLUGIN_ID);
-
-    }
-
-    @BeforeEach
-    void setup() throws Exception {
-            buildFile = new File(testProjectDir, "build.gradle");
-            writeToFile(buildFile, createPluginsSection(Stream.of(FREGE_PLUGIN_ID)));
-            fregeBuilder = FregeDTOBuilder.getInstance();
-    }
-
-    @AfterEach
-    void cleanup() {
-            testProjectDir.delete();
-    }
-
-    @Nested
-    @TestInstance(Lifecycle.PER_CLASS)
-    @IndicativeSentencesGeneration(separator = " -> ", generator = DisplayNameGenerator.ReplaceUnderscores.class)
-    class Setup_frege_task_works {
-
-            @Test
-            void given_minimal_build_file_config() throws Exception {
-                    String minimalBuildFileConfig = createFregeSection(
-                                    fregeBuilder.version("'3.25.84'").release("'3.25alpha'").build());
-                    appendToFile(buildFile, minimalBuildFileConfig);
-
-                    BuildResult result = runGradleTask(SETUP_FREGE_TASK_NAME);
-
-                    assertTrue(project.getTasks().getByName(SETUP_FREGE_TASK_NAME) instanceof SetupFregeTask);
-                    assertEquals(SUCCESS, result.task(":" + SETUP_FREGE_TASK_NAME).getOutcome());
-                    assertTrue(testProjectDir.toPath()
-                                    .resolve(Paths.get(DEFAULT_DOWNLOAD_DIRECTORY, "frege3.25.84.jar"))
-                                    .toFile().exists());
-            }
-
-            @Test
-            void given_custom_frege_compiler_download_directory_in_build_file_config() throws Exception {
-                    String buildFileConfigWithCustomDownloadDir = createFregeSection(fregeBuilder
-                                    .version("'3.25.84'")
-                                    .release("'3.25alpha'")
-                                    .compilerDownloadDir("layout.projectDirectory.dir('dist')").build());
-                    appendToFile(buildFile, buildFileConfigWithCustomDownloadDir);
-
-                    BuildResult result = runGradleTask(SETUP_FREGE_TASK_NAME);
-
-                    assertTrue(project.getTasks().getByName(SETUP_FREGE_TASK_NAME) instanceof SetupFregeTask);
-                    assertEquals(SUCCESS, result.task(":" + SETUP_FREGE_TASK_NAME).getOutcome());
-                    assertTrue(testProjectDir.toPath().resolve(Paths.get("dist", "frege3.25.84.jar")).toFile()
-                                    .exists());
-            }
-    }
-
-    @Nested
-    @TestInstance(Lifecycle.PER_CLASS)
-    @IndicativeSentencesGeneration(separator = " -> ", generator = DisplayNameGenerator.ReplaceUnderscores.class)
-    class Compile_frege_task_works {
-
-            @Test
-            void given_frege_code_in_default_source_dir_and_minimal_build_file_config() throws Exception {
-                    String completionFr = "Completion.fr";
-                    String minimalBuildFileConfig = createFregeSection(
-                                    fregeBuilder.version("'3.25.84'").release("'3.25alpha'").build());
-                    setupDefaultFregeProjectStructure(SIMPLE_FREGE_CODE, completionFr, minimalBuildFileConfig);
-
-                    BuildResult result = runGradleTask(COMPILE_FREGE_TASK_NAME);
-
-                    assertTrue(project.getTasks().getByName(COMPILE_FREGE_TASK_NAME) instanceof CompileFregeTask);
-                    assertEquals(SUCCESS, result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-                    assertTrue(new File(
-                                    testProjectDir.getAbsolutePath()
-                                                    + "/build/classes/main/frege/ch/fhnw/thga/Completion.java")
-                                                                    .exists());
-                    assertTrue(new File(
-                                    testProjectDir.getAbsolutePath()
-                                                    + "/build/classes/main/frege/ch/fhnw/thga/Completion.class")
-                                                                    .exists());
-            }
-
-            @Test
-            void given_frege_code_and_many_compiler_flags() throws Exception {
-                    String completionFr = "Completion.fr";
-                    String buildConfigWithCompilerFlags = createFregeSection(fregeBuilder.version("'3.25.84'")
-                                    .release("'3.25alpha'").compilerFlags("['-v', '-make', '-O', '-hints']")
-                                    .build());
-                    setupDefaultFregeProjectStructure(SIMPLE_FREGE_CODE, completionFr,
-                                    buildConfigWithCompilerFlags);
-
-                    BuildResult result = runGradleTask(COMPILE_FREGE_TASK_NAME);
-
-                    assertTrue(project.getTasks().getByName(COMPILE_FREGE_TASK_NAME) instanceof CompileFregeTask);
-                    assertEquals(SUCCESS, result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-                    assertTrue(new File(
-                                    testProjectDir.getAbsolutePath()
-                                                    + "/build/classes/main/frege/ch/fhnw/thga/Completion.java")
-                                                                    .exists());
-                    assertTrue(new File(
-                                    testProjectDir.getAbsolutePath()
-                                                    + "/build/classes/main/frege/ch/fhnw/thga/Completion.class")
-                                                                    .exists());
-            }
-
-            @Test
-            void given_frege_code_in_custom_source_dir_and_custom_output_dir_and_minimal_build_file_config()
-                            throws Exception {
-                    Path customMainSourceDir = testProjectDir.toPath().resolve(Paths.get("src", "frege"));
-                    Files.createDirectories(customMainSourceDir);
-                    File completionFr = customMainSourceDir.resolve("Completion.fr").toFile();
-                    writeToFile(completionFr, SIMPLE_FREGE_CODE);
-                    String minimalBuildFileConfig = createFregeSection(
-                                    fregeBuilder.version("'3.25.84'").release("'3.25alpha'")
-                                                    .mainSourceDir("layout.projectDirectory.dir('src/frege')")
-                                                    .outputDir("layout.buildDirectory.dir('frege')").build());
-                    appendToFile(buildFile, minimalBuildFileConfig);
-
-                    BuildResult result = runGradleTask(COMPILE_FREGE_TASK_NAME);
-
-                    assertTrue(project.getTasks().getByName(COMPILE_FREGE_TASK_NAME) instanceof CompileFregeTask);
-                    assertEquals(SUCCESS, result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-                    assertTrue(
-                                    new File(testProjectDir.getAbsolutePath()
-                                                    + "/build/frege/ch/fhnw/thga/Completion.java").exists());
-                    assertTrue(
-                                    new File(testProjectDir.getAbsolutePath()
-                                                    + "/build/frege/ch/fhnw/thga/Completion.class").exists());
-            }
-
-            @Test
-            void and_is_up_to_date_given_no_code_changes() throws Exception {
-                    String completionFr = "Completion.fr";
-                    String minimalBuildFileConfig = createFregeSection(
-                                    fregeBuilder.version("'3.25.84'").release("'3.25alpha'").build());
-                    setupDefaultFregeProjectStructure(SIMPLE_FREGE_CODE, completionFr, minimalBuildFileConfig);
-
-                    BuildResult first = runGradleTask(COMPILE_FREGE_TASK_NAME);
-                    assertEquals(SUCCESS, first.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-
-                    BuildResult second = runGradleTask(COMPILE_FREGE_TASK_NAME);
-                    assertEquals(UP_TO_DATE, second.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-            }
-
-            @Test
-            void and_is_cached_given_cache_hit() throws Exception {
-                    String completionFr = "Completion.fr";
-                    String minimalBuildFileConfig = createFregeSection(
-                                    fregeBuilder.version("'3.25.84'").release("'3.25alpha'").build());
-                    setupDefaultFregeProjectStructure(SIMPLE_FREGE_CODE, completionFr, minimalBuildFileConfig);
-
-                    BuildResult first = runGradleTask(COMPILE_FREGE_TASK_NAME, "--build-cache");
-                    assertEquals(SUCCESS, first.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-
-                    String codeChange = String.join(NEW_LINE, "module ch.fhnw.thga.Completion where", NEW_LINE,
-                                    NEW_LINE,
-                                    "  frob :: Int -> (Int, String)", NEW_LINE, "  frob i = (i, \"Frege rocks\")",
-                                    NEW_LINE);
-                    setupDefaultFregeProjectStructure(codeChange, completionFr, "");
-
-                    BuildResult second = runGradleTask(COMPILE_FREGE_TASK_NAME, "--build-cache");
-                    assertEquals(SUCCESS, second.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-
-                    setupDefaultFregeProjectStructure(SIMPLE_FREGE_CODE, completionFr, "");
-                    BuildResult third = runGradleTask(COMPILE_FREGE_TASK_NAME, "--build-cache");
-                    assertEquals(FROM_CACHE, third.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-            }
-
-            @Test
-            void given_two_dependent_frege_files_in_default_source_dir_and_minimal_build_file_config()
-                            throws Exception {
-                    String completionFr = "Completion.fr";
-                    String frobFr = "Frob.fr";
-                    String frobCode = String.join(NEW_LINE, "module ch.fhnw.thga.Frob where", NEW_LINE, NEW_LINE,
-                                    "import ch.fhnw.thga.Completion (complete)", NEW_LINE,
-                                    "frob i = complete $ i + i", NEW_LINE);
-
-                    String minimalBuildFileConfig = createFregeSection(
-                                    fregeBuilder.version("'3.25.84'").release("'3.25alpha'").build());
-                    setupDefaultFregeProjectStructure(SIMPLE_FREGE_CODE, completionFr, minimalBuildFileConfig);
-                    setupDefaultFregeProjectStructure(frobCode, frobFr, "");
-
-                    BuildResult result = runGradleTask(COMPILE_FREGE_TASK_NAME);
-
-                    assertTrue(project.getTasks().getByName(COMPILE_FREGE_TASK_NAME) instanceof CompileFregeTask);
-                    assertEquals(SUCCESS, result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-                    assertTrue(new File(
-                                    testProjectDir.getAbsolutePath()
-                                                    + "/build/classes/main/frege/ch/fhnw/thga/Completion.java")
-                                                                    .exists());
-                    assertTrue(new File(
-                                    testProjectDir.getAbsolutePath()
-                                                    + "/build/classes/main/frege/ch/fhnw/thga/Completion.class")
-                                                                    .exists());
-                    assertTrue(new File(testProjectDir.getAbsolutePath()
-                                    + "/build/classes/main/frege/ch/fhnw/thga/Frob.java")
-                                                    .exists());
-                    assertTrue(new File(testProjectDir.getAbsolutePath()
-                                    + "/build/classes/main/frege/ch/fhnw/thga/Frob.class")
-                                                    .exists());
-            }
-    }
-
-    @Nested
-    @TestInstance(Lifecycle.PER_CLASS)
-    @IndicativeSentencesGeneration(separator = " -> ", generator = DisplayNameGenerator.ReplaceUnderscores.class)
-    class Compile_frege_task_fails {
-            @Test
-            void given_frege_code_and_illegal_compiler_flags() throws Exception {
-                    String completionFr = "Completion.fr";
-                    String buildConfigWithIllegalCompilerFlags = createFregeSection(fregeBuilder
-                                    .version("'3.25.84'")
-                                    .release("'3.25alpha'").compilerFlags("['-make', '-bla']").build());
-                    setupDefaultFregeProjectStructure(SIMPLE_FREGE_CODE, completionFr,
-                                    buildConfigWithIllegalCompilerFlags);
-
-                    BuildResult result = runAndFailGradleTask(COMPILE_FREGE_TASK_NAME);
-
-                    assertTrue(project.getTasks().getByName(COMPILE_FREGE_TASK_NAME) instanceof CompileFregeTask);
-                    assertEquals(FAILED, result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-            }
-
-            @Test
-            void given_two_dependent_frege_files_in_default_source_dir_and_without_make_compiler_flag()
-                            throws Exception {
-                    String completionFr = "Completion.fr";
-                    String frobFr = "Frob.fr";
-                    String frobCode = String.join(NEW_LINE, "module ch.fhnw.thga.Frob where", NEW_LINE, NEW_LINE,
-                                    "import ch.fhnw.thga.Completion (complete)", NEW_LINE,
-                                    "frob i = complete $ i + i", NEW_LINE);
-
-                    String minimalBuildFileConfigWithoutMake = createFregeSection(
-                                    fregeBuilder.version("'3.25.84'").release("'3.25alpha'").compilerFlags("['-v']")
-                                                    .build());
-                    setupDefaultFregeProjectStructure(SIMPLE_FREGE_CODE, completionFr,
-                                    minimalBuildFileConfigWithoutMake);
-                    setupDefaultFregeProjectStructure(frobCode, frobFr, "");
-
-                    BuildResult result = runAndFailGradleTask(COMPILE_FREGE_TASK_NAME);
-
-                    assertTrue(project.getTasks().getByName(COMPILE_FREGE_TASK_NAME) instanceof CompileFregeTask);
-                    assertEquals(FAILED, result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-            }
-    }
-
-    @Nested
-    @TestInstance(Lifecycle.PER_CLASS)
-    @IndicativeSentencesGeneration(separator = " -> ", generator = DisplayNameGenerator.ReplaceUnderscores.class)
-    class Run_frege_task_works {
-            @Test
-            void given_frege_file_with_main_function_and_main_module_config() throws Exception {
-                    String fregeCode = String.join(NEW_LINE, "module ch.fhnw.thga.Main where", NEW_LINE, NEW_LINE,
-                                    "  main = do", NEW_LINE, "    println \"Frege rocks\"", NEW_LINE);
-                    String mainFr = "Main.fr";
-                    String buildFileConfig = createFregeSection(
-                                    fregeBuilder.version("'3.25.84'").release("'3.25alpha'")
-                                                    .mainModule("'ch.fhnw.thga.Main'").build());
-                    setupDefaultFregeProjectStructure(fregeCode, mainFr, buildFileConfig);
-
-                    BuildResult result = runGradleTask(RUN_FREGE_TASK_NAME);
-                    assertTrue(project.getTasks().getByName(RUN_FREGE_TASK_NAME) instanceof RunFregeTask);
-                    assertEquals(SUCCESS, result.task(":" + RUN_FREGE_TASK_NAME).getOutcome());
-                    assertTrue(result.getOutput().contains("Frege rocks"));
-            }
-
-            @Test
-            void given_frege_file_without_main_function() throws Exception {
-                    String completionFr = "Completion.fr";
-                    String buildFileConfig = createFregeSection(
-                                    fregeBuilder.version("'3.25.84'").release("'3.25alpha'")
-                                                    .mainModule("'ch.fhnw.thga.Completion'").build());
-                    setupDefaultFregeProjectStructure(SIMPLE_FREGE_CODE, completionFr, buildFileConfig);
-
-                    BuildResult result = runAndFailGradleTask(RUN_FREGE_TASK_NAME);
-                    assertTrue(project.getTasks().getByName(RUN_FREGE_TASK_NAME) instanceof RunFregeTask);
-                    assertEquals(FAILED, result.task(":" + RUN_FREGE_TASK_NAME).getOutcome());
-                    assertTrue(result.getOutput().contains("Main method not found"));
-            }
-
-            @Test
-            void given_frege_file_with_main_function_and_main_module_command_line_option() throws Exception {
-                    String fregeCode = String.join(NEW_LINE, "module ch.fhnw.thga.Main where", NEW_LINE, NEW_LINE,
-                                    "  main = do", NEW_LINE, "    println \"Frege rocks\"", NEW_LINE);
-                    String mainFr = "Main.fr";
-                    String buildFileConfig = createFregeSection(
-                                    fregeBuilder.version("'3.25.84'").release("'3.25alpha'").build());
-                    setupDefaultFregeProjectStructure(fregeCode, mainFr, buildFileConfig);
-
-                    BuildResult result = runGradleTask(RUN_FREGE_TASK_NAME, "--mainModule=ch.fhnw.thga.Main");
-                    assertTrue(project.getTasks().getByName(RUN_FREGE_TASK_NAME) instanceof RunFregeTask);
-                    assertEquals(SUCCESS, result.task(":" + RUN_FREGE_TASK_NAME).getOutcome());
-                    assertTrue(result.getOutput().contains("Frege rocks"));
-            }
-    }
-
-    @Nested
-    @TestInstance(Lifecycle.PER_CLASS)
-    @IndicativeSentencesGeneration(
-        separator = " -> ",
-        generator = DisplayNameGenerator.ReplaceUnderscores.class)
-    class Deps_frege_task_works {
-        @Test
-        void given_minimal_build_file_config() throws Exception {
-            String completionFr           = "Completion.fr";
-            String minimalBuildFileConfig = createFregeSection(
-                fregeBuilder
-                .version("'3.25.84'")
-                .release("'3.25alpha'")
-                .build());
-            setupDefaultFregeProjectStructure(
-                SIMPLE_FREGE_CODE,
-                completionFr,
-                minimalBuildFileConfig);
-
-            BuildResult result = runGradleTask(
-                DEPS_FREGE_TASK_NAME,
-                "-q",
-                String.format("--replSource=%s", completionFr));
-
-            assertTrue(
-                project.getTasks().getByName(DEPS_FREGE_TASK_NAME)
-                instanceof DependencyFregeTask);
-            assertEquals(SUCCESS, result.task(":" + DEPS_FREGE_TASK_NAME).getOutcome());
-            assertTrue(result.getOutput().contains("frege3.25.84.jar"));
-            assertFalse(result.getOutput().contains("Completion.java"));
-            assertFalse(
-                testProjectDir
-                .toPath()
-                .resolve("/build/classes/main/frege/ch/fhnw/thga/Completion.java").toFile()
-                .exists());
-        }
-
-
-        @Test
-        void given_build_file_config_with_dependencies() throws Exception {
-            String completionFr           = "Completion.fr";
-            String minimalBuildFileConfig = createFregeSection(
-                fregeBuilder
-                .version("'3.25.84'")
-                .release("'3.25alpha'")
-                .build());
-            setupDefaultFregeProjectStructure(
-                SIMPLE_FREGE_CODE,
-                completionFr,
-                minimalBuildFileConfig);
-            appendToFile(
-                buildFile,
-                String.join(
-                    System.lineSeparator(),
-                    "repositories {",
-                      "mavenCentral()",
-                    "}"));
-            appendToFile(
-                buildFile,
-                String.join(
-                    System.lineSeparator(),
-                    "dependencies {",
-                      "implementation group: 'org.json', name: 'json', version: '20211205'",
-                    "}"));
-
-            BuildResult result = runGradleTask(
-                DEPS_FREGE_TASK_NAME,
-                "-q",
-                String.format("--replSource=%s", completionFr));
-
-            assertTrue(
-                project.getTasks().getByName(DEPS_FREGE_TASK_NAME)
-                instanceof DependencyFregeTask);
-            assertEquals(SUCCESS, result.task(":" + DEPS_FREGE_TASK_NAME).getOutcome());
-            assertTrue(result.getOutput().contains("frege3.25.84.jar"));
-            assertTrue(result.getOutput().contains("org.json"));
-            assertFalse(result.getOutput().contains("Completion.java"));
-            assertFalse(
-                testProjectDir
-                .toPath()
-                .resolve("/build/classes/main/frege/ch/fhnw/thga/Completion.java").toFile()
-                .exists());
-        }
-    }
-
-    @Nested
-    @TestInstance(Lifecycle.PER_CLASS)
-    @IndicativeSentencesGeneration(
-        separator = " -> ",
-        generator = DisplayNameGenerator.ReplaceUnderscores.class)
-    class Repl_frege_task_works
-    {
-        @Test
-        void given_minimal_build_file_config_with_replModule() throws Exception
-        {
-            String completionFr            = "Completion.fr";
-            String minimalReplModuleConfig = createFregeSection(
-                fregeBuilder
-                .version("'3.25.84'")
-                .release("'3.25alpha'")
-                .replSource(String.format("'%s'", completionFr))
-                .build());
-            setupDefaultFregeProjectStructure(
-                SIMPLE_FREGE_CODE,
-                completionFr,
-                minimalReplModuleConfig);
-
-            BuildResult result = runGradleTask(REPL_FREGE_TASK_NAME);
-
-            assertTrue(
-                project.getTasks().getByName(REPL_FREGE_TASK_NAME)
-                instanceof ReplFregeTask);
-            assertEquals(SUCCESS, result.task(":" + REPL_FREGE_TASK_NAME).getOutcome());
-            assertTrue(result.getOutput().contains("java -cp"));
-            assertTrue(result.getOutput().contains("frege3.25.84.jar"));
-            assertFalse(result.getOutput().contains("Completion.java"));
-            assertFalse(
-                testProjectDir
-                .toPath()
-                .resolve("/build/classes/main/frege/ch/fhnw/thga/Completion.java").toFile()
-                .exists());
-        }
-    }
-
-    @Nested
-    @TestInstance(Lifecycle.PER_CLASS)
-    @IndicativeSentencesGeneration(
-        separator = " -> ",
-        generator = DisplayNameGenerator.ReplaceUnderscores.class)
-    class Repl_frege_task_fails
-    {
-        @Test
-        void given_minimal_build_file_config_without_repl_module() throws Exception
-        {
-            String completionFr           = "Completion.fr";
-            String minimalBuildFileConfig = createFregeSection(
-                fregeBuilder
-                .version("'3.25.84'")
-                .release("'3.25alpha'")
-                .build());
-            setupDefaultFregeProjectStructure(
-                SIMPLE_FREGE_CODE,
-                completionFr,
-                minimalBuildFileConfig);
-
-            BuildResult result = runAndFailGradleTask(REPL_FREGE_TASK_NAME);
-
-            assertTrue(
-                project.getTasks().getByName(REPL_FREGE_TASK_NAME)
-                instanceof ReplFregeTask);
-            assertEquals(FAILED, result.task(":" + COMPILE_FREGE_TASK_NAME).getOutcome());
-        }
-    }
-}
\ No newline at end of file
diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/ReplFregeTaskFunctionalTest.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/ReplFregeTaskFunctionalTest.java
new file mode 100644
index 0000000..652a3c2
--- /dev/null
+++ b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/ReplFregeTaskFunctionalTest.java
@@ -0,0 +1,183 @@
+package ch.fhnw.thga.gradleplugins;
+
+import static ch.fhnw.thga.gradleplugins.FregeExtension.DEFAULT_RELATIVE_SOURCE_DIR;
+import static ch.fhnw.thga.gradleplugins.FregePlugin.REPL_FREGE_TASK_NAME;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.COMPLETION_FR;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.MINIMAL_BUILD_FILE_CONFIG;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.NEW_LINE;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.assertFileDoesNotExist;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.assertFileExists;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.createFregeSection;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.runAndFailGradleTask;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.runGradleTask;
+import static org.gradle.testkit.runner.TaskOutcome.FAILED;
+import static org.gradle.testkit.runner.TaskOutcome.SUCCESS;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.File;
+import java.nio.file.Paths;
+import java.util.stream.Stream;
+
+import org.gradle.api.Project;
+import org.gradle.testkit.runner.BuildResult;
+import org.junit.jupiter.api.DisplayNameGenerator;
+import org.junit.jupiter.api.IndicativeSentencesGeneration;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import ch.fhnw.thga.gradleplugins.fregeproject.FregeProjectBuilder;
+import ch.fhnw.thga.gradleplugins.fregeproject.FregeSourceFile;
+
+public class ReplFregeTaskFunctionalTest
+{
+    @Nested
+    @IndicativeSentencesGeneration(
+        generator = DisplayNameGenerator.ReplaceUnderscores.class)
+    class Repl_frege_task_works
+    {
+        @Test
+        void given_minimal_build_file_config_with_repl_module(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            String replModuleConfig = createFregeSection(
+                FregeDTOBuilder
+                .builder()
+                .version("'3.25.84'")
+                .release("'3.25alpha'")
+                .replModule("'ch.fhnw.thga.Completion'")
+                .build()
+            );
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(replModuleConfig)
+                .fregeSourceFiles(() -> Stream.of(COMPLETION_FR))
+                .build();
+                                                                                         
+            BuildResult result = runGradleTask(testProjectDir, REPL_FREGE_TASK_NAME);
+                                                                                         
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(REPL_FREGE_TASK_NAME)
+                instanceof ReplFregeTask);
+            assertEquals(
+                SUCCESS,
+                result.task(":" + REPL_FREGE_TASK_NAME).getOutcome());
+            assertTrue(result.getOutput().contains("java -cp"));
+            assertTrue(result.getOutput().contains("frege3.25.84.jar"));
+            assertTrue(result.getOutput().contains(
+                Paths.get(COMPLETION_FR.getFregeModulePath()).normalize().toString())
+            );
+            assertFileDoesNotExist(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Completion.java"
+            );
+            assertFileDoesNotExist(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Completion.class"
+            );
+        }
+
+        @Test
+        void given_dependent_frege_files_with_command_line_repl_module_option(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            String frobCode = String.join(
+                NEW_LINE,
+                "module ch.fhnw.thga.Frob where",
+                NEW_LINE,
+                NEW_LINE,
+                "import ch.fhnw.thga.Completion (complete)",
+                NEW_LINE,
+                "frob i = complete $ i + i",
+                NEW_LINE
+            );
+            FregeSourceFile frob_FR = new FregeSourceFile(
+                String.format(
+                    "%s/%s",
+                    DEFAULT_RELATIVE_SOURCE_DIR,
+                    "ch/fhnw/thga/Frob.fr"
+                ),
+                frobCode);
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(MINIMAL_BUILD_FILE_CONFIG)
+                .fregeSourceFiles(() -> Stream.of(COMPLETION_FR, frob_FR))
+                .build();
+            
+            BuildResult result = runGradleTask(
+                testProjectDir,
+                REPL_FREGE_TASK_NAME,
+                "--replModule=ch.fhnw.thga.Frob"
+            );
+            
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(REPL_FREGE_TASK_NAME)
+                instanceof ReplFregeTask);
+            assertEquals(
+                SUCCESS,
+                result.task(":" + REPL_FREGE_TASK_NAME).getOutcome());
+            assertTrue(result.getOutput().contains("java -cp"));
+            assertTrue(result.getOutput().contains("frege3.25.84.jar"));
+            assertTrue(result.getOutput().contains(
+                Paths.get(frob_FR.getFregeModulePath()).normalize().toString())
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Completion.java"
+            );
+            assertFileExists(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Completion.class"
+            );
+            assertFileDoesNotExist(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Frob.java"
+            );
+            assertFileDoesNotExist(
+                testProjectDir,
+                "build/classes/main/frege/ch/fhnw/thga/Frob.class"
+            );
+        }
+    }
+
+    @Nested
+    @IndicativeSentencesGeneration(
+        generator = DisplayNameGenerator.ReplaceUnderscores.class)
+    class Repl_frege_task_fails
+    {
+        @Test
+        void given_minimal_build_file_config_without_repl_module(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(MINIMAL_BUILD_FILE_CONFIG)
+                .fregeSourceFiles(() -> Stream.of(COMPLETION_FR))
+                .build();
+                                                                                         
+            BuildResult result = runAndFailGradleTask(testProjectDir, REPL_FREGE_TASK_NAME);
+
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(REPL_FREGE_TASK_NAME)
+                instanceof ReplFregeTask
+            );
+            assertEquals(
+                FAILED,
+                result.task(":" + REPL_FREGE_TASK_NAME).getOutcome()
+            );
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/RunFregeTaskFunctionalTest.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/RunFregeTaskFunctionalTest.java
new file mode 100644
index 0000000..c4d5bad
--- /dev/null
+++ b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/RunFregeTaskFunctionalTest.java
@@ -0,0 +1,179 @@
+package ch.fhnw.thga.gradleplugins;
+
+import static ch.fhnw.thga.gradleplugins.FregeExtension.DEFAULT_RELATIVE_SOURCE_DIR;
+import static ch.fhnw.thga.gradleplugins.FregePlugin.RUN_FREGE_TASK_NAME;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.NEW_LINE;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.createFregeSection;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.runAndFailGradleTask;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.runGradleTask;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.MINIMAL_BUILD_FILE_CONFIG;
+import static org.gradle.testkit.runner.TaskOutcome.FAILED;
+import static org.gradle.testkit.runner.TaskOutcome.SUCCESS;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.File;
+import java.util.stream.Stream;
+
+import org.gradle.api.Project;
+import org.gradle.testkit.runner.BuildResult;
+import org.junit.jupiter.api.DisplayNameGenerator;
+import org.junit.jupiter.api.IndicativeSentencesGeneration;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import ch.fhnw.thga.gradleplugins.fregeproject.FregeProjectBuilder;
+import ch.fhnw.thga.gradleplugins.fregeproject.FregeSourceFile;
+
+public class RunFregeTaskFunctionalTest
+{
+    private static final FregeSourceFile MAIN_FR = new FregeSourceFile(
+        String.format(
+            "%s/%s",
+            DEFAULT_RELATIVE_SOURCE_DIR,
+            "ch/fhnw/thga/Main.fr"
+        ),
+        String.join(
+            NEW_LINE,
+            "module ch.fhnw.thga.Main where",
+            NEW_LINE,
+            NEW_LINE,
+            "  main = do",
+            NEW_LINE,
+            "    println \"Frege rocks\"",
+            NEW_LINE
+        )
+    );
+    @Nested
+    @IndicativeSentencesGeneration(
+        separator = " -> ",
+        generator = DisplayNameGenerator.ReplaceUnderscores.class
+    )
+    class Run_frege_task_works
+    {
+        @Test
+        void given_frege_file_with_main_function_and_main_module_config(
+            @TempDir File testProjectDir)
+            throws Exception 
+        {
+            String mainBuildConfig = createFregeSection(
+                FregeDTOBuilder
+                .builder()
+                .version("'3.25.84'")
+                .release("'3.25alpha'")
+                .mainModule("'ch.fhnw.thga.Main'")
+                .build()
+            );
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(mainBuildConfig)
+                .fregeSourceFiles(() -> Stream.of(MAIN_FR))
+                .build();
+            
+            BuildResult result = runGradleTask(testProjectDir, RUN_FREGE_TASK_NAME);
+            
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(RUN_FREGE_TASK_NAME) 
+                instanceof RunFregeTask
+            );
+            assertEquals(
+                SUCCESS,
+                result.task(":" + RUN_FREGE_TASK_NAME).getOutcome()
+            );
+            assertTrue(result.getOutput().contains("Frege rocks"));
+        }
+
+        @Test
+        void given_frege_file_with_main_function_and_main_module_command_line_option(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(MINIMAL_BUILD_FILE_CONFIG)
+                .fregeSourceFiles(() -> Stream.of(MAIN_FR))
+                .build();
+            
+            BuildResult result = runGradleTask(
+                testProjectDir,
+                RUN_FREGE_TASK_NAME,
+                "--mainModule=ch.fhnw.thga.Main");
+            
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(RUN_FREGE_TASK_NAME) 
+                instanceof RunFregeTask
+            );
+            assertEquals(
+                SUCCESS,
+                result.task(":" + RUN_FREGE_TASK_NAME).getOutcome()
+            );
+            assertTrue(result.getOutput().contains("Frege rocks"));
+        }
+    }
+    @Nested
+    @IndicativeSentencesGeneration(
+        separator = " -> ",
+        generator = DisplayNameGenerator.ReplaceUnderscores.class
+    )
+    class Run_frege_task_fails
+    {
+        @Test
+        void given_frege_file_without_main_function(
+            @TempDir File testProjectDir)
+            throws Exception
+        {
+            String mainBuildConfig = createFregeSection(
+                FregeDTOBuilder
+                .builder()
+                .version("'3.25.84'")
+                .release("'3.25alpha'")
+                .mainModule("'ch.fhnw.thga.Main'")
+                .build()
+            );
+            Project project = FregeProjectBuilder
+                .builder()
+                .projectRoot(testProjectDir)
+                .buildFile(mainBuildConfig)
+                .fregeSourceFiles(() -> Stream.of(new FregeSourceFile(
+                    String.format(
+                        "%s/%s",
+                        DEFAULT_RELATIVE_SOURCE_DIR,
+                        "ch/fhnw/thga/Main.fr"
+                    ),
+                    String.join(
+                        NEW_LINE,
+                        "module ch.fhnw.thga.Main where",
+                        NEW_LINE,
+                        NEW_LINE,
+                        "  add a b = a + b",
+                        NEW_LINE
+                    )
+                )))
+                .build();
+
+            BuildResult result = runAndFailGradleTask(
+                testProjectDir,
+                RUN_FREGE_TASK_NAME
+            );
+
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(RUN_FREGE_TASK_NAME) 
+                instanceof RunFregeTask
+            );
+            assertEquals(
+                FAILED,
+                result.task(":" + RUN_FREGE_TASK_NAME).getOutcome()
+            );
+            assertTrue(result.getOutput().contains("Main method not found"));
+        }
+    }
+}
diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/SetupFregeTaskFunctionalTest.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/SetupFregeTaskFunctionalTest.java
new file mode 100644
index 0000000..6781764
--- /dev/null
+++ b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/SetupFregeTaskFunctionalTest.java
@@ -0,0 +1,104 @@
+package ch.fhnw.thga.gradleplugins;
+
+import static ch.fhnw.thga.gradleplugins.FregeExtension.DEFAULT_RELATIVE_COMPILER_DOWNLOAD_DIR;
+import static ch.fhnw.thga.gradleplugins.FregePlugin.SETUP_FREGE_TASK_NAME;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.createFregeSection;
+import static ch.fhnw.thga.gradleplugins.SharedFunctionalTestLogic.runGradleTask;
+import static org.gradle.testkit.runner.TaskOutcome.SUCCESS;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.File;
+import java.nio.file.Paths;
+
+import org.gradle.api.Project;
+import org.gradle.testkit.runner.BuildResult;
+import org.junit.jupiter.api.DisplayNameGenerator;
+import org.junit.jupiter.api.IndicativeSentencesGeneration;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Tag;
+import org.junit.jupiter.api.io.TempDir;
+
+import ch.fhnw.thga.gradleplugins.fregeproject.FregeProjectBuilder;
+import ch.fhnw.thga.gradleplugins.fregeproject.ProjectRoot;
+
+@Tag("network")
+class SetupFregeTaskFunctionalTest
+{
+    private static FregeDTOBuilder FREGE_BUILDER             = FregeDTOBuilder.builder();
+    private static ProjectRoot FREGE_PROJECT_BUILDER = FregeProjectBuilder.builder();
+
+    @Nested
+    @IndicativeSentencesGeneration(separator = " -> ", generator = DisplayNameGenerator.ReplaceUnderscores.class)
+    class Setup_frege_task_works {
+        @Test
+        void given_minimal_build_file_config(@TempDir File testProjectDir) throws Exception
+        {
+            String minimalBuildFileConfig = createFregeSection(
+                FREGE_BUILDER
+                    .version("'3.25.84'")
+                    .release("'3.25alpha'")
+                    .build()
+            );
+
+            Project project = FREGE_PROJECT_BUILDER
+                .projectRoot(testProjectDir)
+                .buildFile(minimalBuildFileConfig)
+                .useLocalFregeCompiler(false)
+                .build();
+
+            BuildResult result = runGradleTask(testProjectDir, SETUP_FREGE_TASK_NAME);
+    
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(SETUP_FREGE_TASK_NAME) instanceof SetupFregeTask
+            );
+            assertEquals(SUCCESS, result.task(":" + SETUP_FREGE_TASK_NAME).getOutcome());
+            assertTrue(
+                testProjectDir
+                .toPath()
+                .resolve(Paths.get(DEFAULT_RELATIVE_COMPILER_DOWNLOAD_DIR, "frege3.25.84.jar"))
+                .toFile()
+                .exists()
+            );
+        }
+    
+        @Test
+        void given_custom_frege_compiler_download_directory_in_build_file_config(
+            @TempDir File testProjectDir) 
+            throws Exception 
+        {
+            String buildFileConfigWithCustomDownloadDir = createFregeSection(
+                FREGE_BUILDER
+                    .version("'3.25.84'")
+                    .release("'3.25alpha'")
+                    .compilerDownloadDir("layout.projectDirectory.dir('dist')")
+                    .build()
+            );
+
+            Project project = FREGE_PROJECT_BUILDER
+                .projectRoot(testProjectDir)
+                .buildFile(buildFileConfigWithCustomDownloadDir)
+                .useLocalFregeCompiler(false)
+                .build();
+    
+            BuildResult result = runGradleTask(testProjectDir, SETUP_FREGE_TASK_NAME);
+            
+            assertTrue(
+                project
+                .getTasks()
+                .getByName(SETUP_FREGE_TASK_NAME) instanceof SetupFregeTask
+            );
+            assertEquals(SUCCESS, result.task(":" + SETUP_FREGE_TASK_NAME).getOutcome());
+            assertTrue(
+                testProjectDir
+                .toPath()
+                .resolve(Paths.get("dist", "frege3.25.84.jar"))
+                .toFile()
+                .exists()
+            );
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/SharedFunctionalTestLogic.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/SharedFunctionalTestLogic.java
new file mode 100644
index 0000000..f935b28
--- /dev/null
+++ b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/SharedFunctionalTestLogic.java
@@ -0,0 +1,172 @@
+package ch.fhnw.thga.gradleplugins;
+
+import static ch.fhnw.thga.gradleplugins.FregePlugin.FREGE_EXTENSION_NAME;
+import static ch.fhnw.thga.gradleplugins.FregePlugin.FREGE_PLUGIN_ID;
+import static ch.fhnw.thga.gradleplugins.GradleBuildFileConversionTest.createPluginsSection;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static ch.fhnw.thga.gradleplugins.FregeExtension.DEFAULT_RELATIVE_SOURCE_DIR;
+
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.stream.Stream;
+
+import org.gradle.api.Project;
+import org.gradle.testfixtures.ProjectBuilder;
+import org.gradle.testkit.runner.BuildResult;
+import org.gradle.testkit.runner.GradleRunner;
+
+import ch.fhnw.thga.gradleplugins.fregeproject.FregeSourceFile;
+
+public class SharedFunctionalTestLogic
+{
+    public static final String NEW_LINE = System.lineSeparator();
+    public static final String MINIMAL_BUILD_FILE_CONFIG = createFregeSection(
+        FregeDTOBuilder
+        .builder()
+        .version("'3.25.84'")
+        .release("'3.25alpha'")
+        .build()
+    );
+    public static final FregeSourceFile COMPLETION_FR = new FregeSourceFile(
+        String.format("%s/%s",
+            DEFAULT_RELATIVE_SOURCE_DIR,
+            "ch/fhnw/thga/Completion.fr"),
+        String.join
+        (
+            NEW_LINE,
+            "module ch.fhnw.thga.Completion where",
+            NEW_LINE,
+            NEW_LINE,
+            "  complete :: Int -> (Int, String)",
+            NEW_LINE,
+            "  complete i = (i, \"Frege rocks\")",
+            NEW_LINE
+        )
+    );
+
+    public static final boolean fileExists(
+        File testProjectDir,
+        String relativeFilePath)
+    {
+        return testProjectDir
+        .toPath()
+        .resolve(relativeFilePath)
+        .toFile()
+        .exists();
+    }
+
+    public static final void assertFileExists(
+        File testProjectDir,
+        String relativeFilePath)
+    {
+        assertTrue(fileExists(testProjectDir, relativeFilePath));
+    }
+
+
+    public static final void assertFileDoesNotExist(
+        File testProjectDir,
+        String relativeFilePath)
+    {
+        assertFalse(fileExists(testProjectDir, relativeFilePath));
+    }
+    
+    static String createFregeSection(FregeDTO fregeDTO) 
+   {
+        return String.format(
+            "%s {%s  %s%s}",
+            FREGE_EXTENSION_NAME,
+            System.lineSeparator(),
+            fregeDTO.toBuildFile(),
+            System.lineSeparator());
+    }
+
+    private static void writeFile(
+        File destination,
+        String content,
+        boolean append) 
+        throws IOException
+    {
+        try (BufferedWriter output = new BufferedWriter(new FileWriter(destination, append)))
+        {
+                output.write(content);
+        }
+    
+    }
+
+    static File writeToFile(File destination, String content) throws IOException
+    {
+        writeFile(destination, content, false);
+        return destination;
+    }
+
+    static File appendToFile(File destination, String content) throws IOException
+    {
+        writeFile(destination, System.lineSeparator() + content, true);
+        return destination;
+    }
+
+    static BuildResult runGradleTask(File testProjectDir, String... args)
+    {
+        return GradleRunner
+            .create()
+            .withProjectDir(testProjectDir)
+            .withPluginClasspath()
+            .withArguments(args)
+            .build();
+    }
+    
+    static BuildResult runAndFailGradleTask(File testProjectDir, String... args)
+    {
+        return GradleRunner
+            .create()
+            .withProjectDir(testProjectDir)
+            .withPluginClasspath()
+            .withArguments(args)
+            .buildAndFail();
+    }
+
+    static File createSettingsFile(File testProjectDir) throws IOException 
+        {
+            File settingsFile = new File(testProjectDir, "settings.gradle");
+            return writeToFile(settingsFile, "rootProject.name='frege-plugin'");
+        }
+    
+        private static File createFregePluginBuildFile(
+            File testProjectDir)
+            throws IOException
+        {
+            File buildFile = new File(testProjectDir, "build.gradle");
+            return writeToFile(
+                buildFile,
+                createPluginsSection(Stream.of(FREGE_PLUGIN_ID)));
+        }
+    
+        static File createFregeBuildFile(
+            File testProjectDir,
+            String fregeBuildFileConfig)
+            throws IOException
+        {
+            return appendToFile(
+                createFregePluginBuildFile(
+                    testProjectDir),
+                    fregeBuildFileConfig);
+        }
+    
+        static Project createFregeGradleProject(
+            File testProjectDir,
+            String fregeBuildFileConfig)
+            throws Exception
+        {
+            createSettingsFile(testProjectDir);
+            createFregeBuildFile(testProjectDir, fregeBuildFileConfig);
+            Project project = ProjectBuilder
+                .builder()
+                .withProjectDir(testProjectDir)
+                .build();
+            project.getPluginManager().apply(FREGE_PLUGIN_ID);
+            return project;
+        }
+}
diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/Build.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/Build.java
new file mode 100644
index 0000000..175ccaa
--- /dev/null
+++ b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/Build.java
@@ -0,0 +1,15 @@
+package ch.fhnw.thga.gradleplugins.fregeproject;
+
+import java.io.IOException;
+import java.util.function.Supplier;
+import java.util.stream.Stream;
+
+import org.gradle.api.Project;
+
+public interface Build
+{
+    Build useLocalFregeCompiler(boolean useLocalFregeCompiler);
+    Build settingsFile(String settingsFile);
+    Build fregeSourceFiles(Supplier<Stream<FregeSourceFile>> fregeSourceFiles);
+    Project build() throws IOException;
+}
diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/BuildFile.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/BuildFile.java
new file mode 100644
index 0000000..ea41350
--- /dev/null
+++ b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/BuildFile.java
@@ -0,0 +1,7 @@
+package ch.fhnw.thga.gradleplugins.fregeproject;
+
+public interface BuildFile
+{
+    Build buildFile(String buildFile);
+
+}
diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/FregeProject.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/FregeProject.java
new file mode 100644
index 0000000..3f4373e
--- /dev/null
+++ b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/FregeProject.java
@@ -0,0 +1,26 @@
+package ch.fhnw.thga.gradleplugins.fregeproject;
+
+import java.io.File;
+import java.util.List;
+
+public class FregeProject
+{
+    public final File settingsFile;
+    public final File buildFile;
+    public final File fregeCompiler;
+    public final List<File> fregeSourceFiles;
+
+    public FregeProject(
+        File settingsFile,
+        File buildFile,
+        File fregeCompiler,
+        List<File> fregeSourceFiles
+        
+    )
+    {
+        this.settingsFile     = settingsFile;
+        this.buildFile        = buildFile;
+        this.fregeCompiler    = fregeCompiler;
+        this.fregeSourceFiles = fregeSourceFiles;
+    }
+}
diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/FregeProjectBuilder.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/FregeProjectBuilder.java
new file mode 100644
index 0000000..0cb0746
--- /dev/null
+++ b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/FregeProjectBuilder.java
@@ -0,0 +1,166 @@
+package ch.fhnw.thga.gradleplugins.fregeproject;
+
+import static ch.fhnw.thga.gradleplugins.FregeExtension.DEFAULT_RELATIVE_COMPILER_DOWNLOAD_DIR;
+import static ch.fhnw.thga.gradleplugins.FregePlugin.FREGE_PLUGIN_ID;
+import static ch.fhnw.thga.gradleplugins.GradleBuildFileConversionTest.createPluginsSection;
+
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardCopyOption;
+import java.util.function.Supplier;
+import java.util.stream.Stream;
+
+import org.gradle.api.Project;
+import org.gradle.testfixtures.ProjectBuilder;
+
+public final class FregeProjectBuilder implements ProjectRoot, BuildFile, Build
+{
+    private static final String LATEST_COMPILER_VERSION = "3.25.84";
+    private static final Path LOCAL_COMPILER_PATH       =
+        Paths.get(String.format(
+            "src/functionalTest/resources/frege%s.jar",
+            LATEST_COMPILER_VERSION)
+        );
+
+    private File projectRoot;
+    private String buildFile                            = createPluginsSection(
+        Stream.of(FREGE_PLUGIN_ID)
+        );
+    private boolean useLocalFregeCompiler               = true;
+    private String settingsFile                         = "rootProject.name='frege-plugin'";
+    private Supplier<Stream<FregeSourceFile>> fregeSourceFiles    = () -> Stream.empty();
+
+    
+    public static ProjectRoot builder()
+    {
+        return new FregeProjectBuilder();
+    }
+ 
+     private static void writeFile(
+         File destination,
+         String content,
+         boolean append) 
+         throws IOException
+     {
+         try (BufferedWriter output = new BufferedWriter(new FileWriter(destination, append)))
+         {
+                 output.write(content);
+         }
+     
+     }
+ 
+     private static File writeToFile(File destination, String content) throws IOException
+     {
+         writeFile(destination, content, false);
+         return destination;
+     }
+
+     private File writeToFile(FregeSourceFile fregeFile)
+     {
+         Path fregeFilePath = projectRoot.toPath().resolve(fregeFile.getFregeModulePath());
+         try
+         {
+            Files.createDirectories(
+            fregeFilePath
+            .getParent()
+        );
+            return writeToFile(
+                fregeFilePath.toFile(),
+                fregeFile.getFregeSourceCode()
+            );
+         } catch (IOException e)
+         {
+             throw new RuntimeException(e.getMessage(), e.getCause());
+         }
+     }
+     
+     private File setupLocalFregeCompilerInDefaultPath() throws IOException
+     {
+         Files.createDirectories(
+             projectRoot
+             .toPath()
+             .resolve(DEFAULT_RELATIVE_COMPILER_DOWNLOAD_DIR));
+            return Files.copy(
+                LOCAL_COMPILER_PATH,
+                projectRoot
+                    .toPath()
+                    .resolve(DEFAULT_RELATIVE_COMPILER_DOWNLOAD_DIR)
+                    .resolve(LOCAL_COMPILER_PATH.getFileName()),
+                StandardCopyOption.REPLACE_EXISTING)
+            .toFile();
+     }
+
+    private FregeProjectBuilder() {}
+
+
+    @Override
+    public Build useLocalFregeCompiler(boolean useLocalFregeCompiler)
+    {
+        this.useLocalFregeCompiler = useLocalFregeCompiler;
+        return this;
+    }
+
+    @Override
+    public Build settingsFile(String settingsFile)
+    {
+        this.settingsFile = String.join(
+            System.lineSeparator(),
+            this.settingsFile,
+            settingsFile
+        );
+        return this;
+    }
+
+    @Override
+    public Build buildFile(String buildFile)
+    {
+        this.buildFile = String.join(
+            System.lineSeparator(),
+            this.buildFile,
+            buildFile
+        );
+        return this;
+    }
+
+    @Override
+    public BuildFile projectRoot(File projectRoot)
+    {
+        this.projectRoot = projectRoot;
+        return this;
+    }
+
+    @Override
+    public Build fregeSourceFiles(Supplier<Stream<FregeSourceFile>> fregeSourceFiles)
+    {
+        this.fregeSourceFiles = fregeSourceFiles;
+        return this;
+    }
+
+    private File createGradleFile(String filename, String content) throws IOException
+    {
+        return writeToFile(
+            new File(projectRoot, filename),
+            content
+        );
+    }
+
+    @Override
+    public Project build() throws IOException
+    {
+        createGradleFile("settings.gradle", settingsFile);
+        createGradleFile("build.gradle", buildFile);
+        if (useLocalFregeCompiler) setupLocalFregeCompilerInDefaultPath();
+        fregeSourceFiles.get().map(this::writeToFile).toArray();
+        Project project = ProjectBuilder
+            .builder()
+            .withProjectDir(projectRoot)
+            .build();
+        project.getPluginManager().apply(FREGE_PLUGIN_ID);
+        return project;
+    }
+}
diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/FregeSourceFile.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/FregeSourceFile.java
new file mode 100644
index 0000000..858f6d4
--- /dev/null
+++ b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/FregeSourceFile.java
@@ -0,0 +1,23 @@
+package ch.fhnw.thga.gradleplugins.fregeproject;
+
+public class FregeSourceFile
+{
+    private final String modulePath;
+    private final String sourceCode;
+
+    public FregeSourceFile(String modulePath, String sourceCode)
+    {
+        this.modulePath = modulePath;
+        this.sourceCode = sourceCode;   
+    }
+
+    public String getFregeModulePath()
+    {
+        return modulePath;
+    }
+
+    public String getFregeSourceCode()
+    {
+        return sourceCode;
+    }
+}
diff --git a/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/ProjectRoot.java b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/ProjectRoot.java
new file mode 100644
index 0000000..2b071ee
--- /dev/null
+++ b/src/functionalTest/java/ch/fhnw/thga/gradleplugins/fregeproject/ProjectRoot.java
@@ -0,0 +1,9 @@
+package ch.fhnw.thga.gradleplugins.fregeproject;
+
+import java.io.File;
+
+public interface ProjectRoot
+{
+    BuildFile projectRoot(File projectRoot);
+    
+}