introduce ArchTests instead of ArchRules #538

The term `ArchRules` is misleading, because it suggests that the class collects instances of `ArchRule`, while in fact it looks for members annotated with `@ArchTest`. This becomes particular clear, if you look at method declarations like `@ArchTest static void rule_method(JavaClasses classes) {..}`. I have thus introduced `ArchTests.in(someClass)` as a new version that makes this clearer (including some Javadoc this time) and kept the old `ArchRules` as a deprecated version for now to be backwards compatible.
I have duplicated quite some code (like whole test classes) and not unified much of the additional complexity by having `ArchTests` as well as `ArchRules`, since this is only temporary and we can kick it out in the near future.

Resolves: #525

Signed-off-by: Peter Gafert <peter.gafert@tngtech.com>

archunit-example/example-junit4/src/test/java/com/tngtech/archunit/exampletest/junit4/RuleLibraryTest.java

@@ -1,8 +1,8 @@
 package com.tngtech.archunit.exampletest.junit4;
 
 import com.tngtech.archunit.junit.AnalyzeClasses;
-import com.tngtech.archunit.junit.ArchRules;
 import com.tngtech.archunit.junit.ArchTest;
+import com.tngtech.archunit.junit.ArchTests;
 import com.tngtech.archunit.junit.ArchUnitRunner;
 import org.junit.experimental.categories.Category;
 import org.junit.runner.RunWith;
@@ -12,11 +12,11 @@
 @AnalyzeClasses(packages = "com.tngtech.archunit.example.layers")
 public class RuleLibraryTest {
     @ArchTest
-    public static final ArchRules LIBRARY = ArchRules.in(RuleSetsTest.class);
+    public static final ArchTests LIBRARY = ArchTests.in(RuleSetsTest.class);
 
     @ArchTest
-    public static final ArchRules FURTHER_CODING_RULES = ArchRules.in(CodingRulesTest.class);
+    public static final ArchTests FURTHER_CODING_RULES = ArchTests.in(CodingRulesTest.class);
 
     @ArchTest
-    public static final ArchRules SLICES_ISOLATION_RULES = ArchRules.in(SlicesIsolationTest.class);
+    public static final ArchTests SLICES_ISOLATION_RULES = ArchTests.in(SlicesIsolationTest.class);
 }

archunit-example/example-junit4/src/test/java/com/tngtech/archunit/exampletest/junit4/RuleSetsTest.java

@@ -1,8 +1,8 @@
 package com.tngtech.archunit.exampletest.junit4;
 
 import com.tngtech.archunit.junit.AnalyzeClasses;
-import com.tngtech.archunit.junit.ArchRules;
 import com.tngtech.archunit.junit.ArchTest;
+import com.tngtech.archunit.junit.ArchTests;
 import com.tngtech.archunit.junit.ArchUnitRunner;
 import org.junit.experimental.categories.Category;
 import org.junit.runner.RunWith;
@@ -12,8 +12,8 @@
 @AnalyzeClasses(packages = "com.tngtech.archunit.example.layers")
 public class RuleSetsTest {
     @ArchTest
-    private final ArchRules CODING_RULES = ArchRules.in(CodingRulesTest.class);
+    private final ArchTests CODING_RULES = ArchTests.in(CodingRulesTest.class);
 
     @ArchTest
-    private final ArchRules NAMING_CONVENTION_RULES = ArchRules.in(NamingConventionTest.class);
+    private final ArchTests NAMING_CONVENTION_RULES = ArchTests.in(NamingConventionTest.class);
 }

archunit-example/example-junit5/src/test/java/com/tngtech/archunit/exampletest/junit5/RuleLibraryTest.java

@@ -1,19 +1,19 @@
 package com.tngtech.archunit.exampletest.junit5;
 
 import com.tngtech.archunit.junit.AnalyzeClasses;
-import com.tngtech.archunit.junit.ArchRules;
 import com.tngtech.archunit.junit.ArchTag;
 import com.tngtech.archunit.junit.ArchTest;
+import com.tngtech.archunit.junit.ArchTests;
 
 @ArchTag("example")
 @AnalyzeClasses(packages = "com.tngtech.archunit.example.layers")
 class RuleLibraryTest {
     @ArchTest
-    static final ArchRules LIBRARY = ArchRules.in(RuleSetsTest.class);
+    static final ArchTests LIBRARY = ArchTests.in(RuleSetsTest.class);
 
     @ArchTest
-    static final ArchRules FURTHER_CODING_RULES = ArchRules.in(CodingRulesTest.class);
+    static final ArchTests FURTHER_CODING_RULES = ArchTests.in(CodingRulesTest.class);
 
     @ArchTest
-    static final ArchRules SLICES_ISOLATION_RULES = ArchRules.in(SlicesIsolationTest.class);
+    static final ArchTests SLICES_ISOLATION_RULES = ArchTests.in(SlicesIsolationTest.class);
 }

archunit-example/example-junit5/src/test/java/com/tngtech/archunit/exampletest/junit5/RuleSetsTest.java

@@ -1,16 +1,16 @@
 package com.tngtech.archunit.exampletest.junit5;
 
 import com.tngtech.archunit.junit.AnalyzeClasses;
-import com.tngtech.archunit.junit.ArchRules;
 import com.tngtech.archunit.junit.ArchTag;
 import com.tngtech.archunit.junit.ArchTest;
+import com.tngtech.archunit.junit.ArchTests;
 
 @ArchTag("example")
 @AnalyzeClasses(packages = "com.tngtech.archunit.example.layers")
 class RuleSetsTest {
     @ArchTest
-    private final ArchRules CODING_RULES = ArchRules.in(CodingRulesTest.class);
+    private final ArchTests CODING_RULES = ArchTests.in(CodingRulesTest.class);
 
     @ArchTest
-    private final ArchRules NAMING_CONVENTION_RULES = ArchRules.in(NamingConventionTest.class);
+    private final ArchTests NAMING_CONVENTION_RULES = ArchTests.in(NamingConventionTest.class);
 }

archunit-integration-test/src/test/java/com/tngtech/archunit/ArchUnitArchitectureTest.java

@@ -16,8 +16,8 @@
 import com.tngtech.archunit.core.importer.ImportOption;
 import com.tngtech.archunit.core.importer.Location;
 import com.tngtech.archunit.junit.AnalyzeClasses;
-import com.tngtech.archunit.junit.ArchRules;
 import com.tngtech.archunit.junit.ArchTest;
+import com.tngtech.archunit.junit.ArchTests;
 import com.tngtech.archunit.junit.ArchUnitRunner;
 import com.tngtech.archunit.lang.ArchRule;
 import org.junit.runner.RunWith;
@@ -57,7 +57,7 @@ public class ArchUnitArchitectureTest {
             .whereLayer("Base").mayOnlyBeAccessedByLayers("Root", "Core", "Lang", "Library", "JUnit");
 
     @ArchTest
-    public static final ArchRules importer_rules = ArchRules.in(ImporterRules.class);
+    public static final ArchTests importer_rules = ArchTests.in(ImporterRules.class);
 
     @ArchTest
     public static final ArchRule types_are_only_resolved_via_reflection_in_allowed_places =
@@ -66,7 +66,7 @@ public class ArchUnitArchitectureTest {
                     .as("no classes should illegally resolve classes via reflection");
 
     @ArchTest
-    public static final ArchRules public_API_rules = ArchRules.in(PublicAPIRules.class);
+    public static final ArchTests public_API_rules = ArchTests.in(PublicAPIRules.class);
 
     private static DescribedPredicate<JavaCall<?>> typeIsIllegallyResolvedViaReflection() {
         DescribedPredicate<JavaCall<?>> explicitlyAllowedUsage =

archunit-junit/junit4/src/main/java/com/tngtech/archunit/junit/ArchRuleDeclaration.java

@@ -68,10 +68,10 @@ boolean shouldBeIgnored() {
     }
 
     static Set<ArchRuleDeclaration<?>> toDeclarations(
-            ArchRules rules, Class<?> testClass, Class<? extends Annotation> archTestAnnotationType, boolean forceIgnore) {
+            ArchTests archTests, Class<?> testClass, Class<? extends Annotation> archTestAnnotationType, boolean forceIgnore) {
 
         ImmutableSet.Builder<ArchRuleDeclaration<?>> result = ImmutableSet.builder();
-        Class<?> definitionLocation = rules.getDefinitionLocation();
+        Class<?> definitionLocation = archTests.getDefinitionLocation();
         for (Field field : getAllFields(definitionLocation, withAnnotation(archTestAnnotationType))) {
             result.addAll(archRuleDeclarationsFrom(testClass, field, definitionLocation, archTestAnnotationType, forceIgnore));
         }
@@ -84,13 +84,13 @@ static Set<ArchRuleDeclaration<?>> toDeclarations(
     private static Set<ArchRuleDeclaration<?>> archRuleDeclarationsFrom(Class<?> testClass, Field field, Class<?> fieldOwner,
             Class<? extends Annotation> archTestAnnotationType, boolean forceIgnore) {
 
-        return ArchRules.class.isAssignableFrom(field.getType()) ?
+        return ArchTests.class.isAssignableFrom(field.getType()) || ArchRules.class.isAssignableFrom(field.getType()) ?
                 toDeclarations(getArchRulesIn(field, fieldOwner), testClass, archTestAnnotationType, forceIgnore || elementShouldBeIgnored(field)) :
                 Collections.<ArchRuleDeclaration<?>>singleton(ArchRuleDeclaration.from(testClass, field, fieldOwner, forceIgnore));
     }
 
-    private static ArchRules getArchRulesIn(Field field, Class<?> fieldOwner) {
-        ArchRules value = getValue(field, fieldOwner);
+    private static ArchTests getArchRulesIn(Field field, Class<?> fieldOwner) {
+        ArchTests value = ArchTests.from(getValue(field, fieldOwner));
         return checkNotNull(value, "Field %s.%s is not initialized", fieldOwner.getName(), field.getName());
     }
 

archunit-junit/junit4/src/main/java/com/tngtech/archunit/junit/ArchUnitRunner.java

@@ -111,22 +111,22 @@ private Collection<ArchTestExecution> findArchRuleFields() {
 
     private Set<ArchTestExecution> findArchRulesIn(FrameworkField ruleField) {
         boolean ignore = elementShouldBeIgnored(ruleField.getField());
-        if (ruleField.getType() == ArchRules.class) {
+        if (ruleField.getType() == ArchTests.class || ruleField.getType() == ArchRules.class) {
             return asTestExecutions(getArchRules(ruleField.getField()), ignore);
         }
         return Collections.<ArchTestExecution>singleton(new ArchRuleExecution(getTestClass().getJavaClass(), ruleField.getField(), ignore));
     }
 
-    private Set<ArchTestExecution> asTestExecutions(ArchRules archRules, boolean forceIgnore) {
+    private Set<ArchTestExecution> asTestExecutions(ArchTests archTests, boolean forceIgnore) {
         ExecutionTransformer executionTransformer = new ExecutionTransformer();
-        for (ArchRuleDeclaration<?> declaration : toDeclarations(archRules, getTestClass().getJavaClass(), ArchTest.class, forceIgnore)) {
+        for (ArchRuleDeclaration<?> declaration : toDeclarations(archTests, getTestClass().getJavaClass(), ArchTest.class, forceIgnore)) {
             declaration.handleWith(executionTransformer);
         }
         return executionTransformer.getExecutions();
     }
 
-    private ArchRules getArchRules(Field field) {
-        return getValue(field, field.getDeclaringClass());
+    private ArchTests getArchRules(Field field) {
+        return ArchTests.from(getValue(field, field.getDeclaringClass()));
     }
 
     private Collection<ArchTestExecution> findArchRuleMethods() {