Introduce BugCheckerRules Refaster rule collection (#526)

error-prone-contrib/pom.xml

@@ -37,7 +37,7 @@
         <dependency>
             <groupId>${groupId.error-prone}</groupId>
             <artifactId>error_prone_test_helpers</artifactId>
-            <scope>test</scope>
+            <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>${project.groupId}</groupId>

error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/BugCheckerRules.java

@@ -0,0 +1,53 @@
+package tech.picnic.errorprone.refasterrules;
+
+import com.google.errorprone.BugCheckerRefactoringTestHelper;
+import com.google.errorprone.BugCheckerRefactoringTestHelper.FixChooser;
+import com.google.errorprone.BugCheckerRefactoringTestHelper.FixChoosers;
+import com.google.errorprone.refaster.Refaster;
+import com.google.errorprone.refaster.annotation.AfterTemplate;
+import com.google.errorprone.refaster.annotation.BeforeTemplate;
+import tech.picnic.errorprone.refaster.annotation.OnlineDocumentation;
+
+/** Refaster rules related to {@link com.google.errorprone.bugpatterns.BugChecker} classes. */
+@OnlineDocumentation
+final class BugCheckerRules {
+  private BugCheckerRules() {}
+
+  /**
+   * Avoid calling {@link BugCheckerRefactoringTestHelper#setFixChooser(FixChooser)} or {@link
+   * BugCheckerRefactoringTestHelper#setImportOrder(String)} with their respective default values.
+   */
+  static final class BugCheckerRefactoringTestHelperIdentity {
+    @BeforeTemplate
+    BugCheckerRefactoringTestHelper before(BugCheckerRefactoringTestHelper helper) {
+      return Refaster.anyOf(
+          helper.setFixChooser(FixChoosers.FIRST), helper.setImportOrder("static-first"));
+    }
+
+    @AfterTemplate
+    BugCheckerRefactoringTestHelper after(BugCheckerRefactoringTestHelper helper) {
+      return helper;
+    }
+  }
+
+  /**
+   * Prefer {@link BugCheckerRefactoringTestHelper.ExpectOutput#expectUnchanged()} over repeating
+   * the input.
+   */
+  // XXX: This rule assumes that the full source code is specified as a single string, e.g. using a
+  // text block. Support for multi-line source code input would require a `BugChecker`
+  // implementation instead.
+  static final class BugCheckerRefactoringTestHelperAddInputLinesExpectUnchanged {
+    @BeforeTemplate
+    BugCheckerRefactoringTestHelper before(
+        BugCheckerRefactoringTestHelper helper, String path, String source) {
+      return helper.addInputLines(path, source).addOutputLines(path, source);
+    }
+
+    @AfterTemplate
+    BugCheckerRefactoringTestHelper after(
+        BugCheckerRefactoringTestHelper helper, String path, String source) {
+      return helper.addInputLines(path, source).expectUnchanged();
+    }
+  }
+}

error-prone-contrib/src/test/java/tech/picnic/errorprone/bugpatterns/FluxFlatMapUsageTest.java

@@ -67,7 +67,6 @@ void identification() {
   @Test
   void replacementFirstSuggestedFix() {
     BugCheckerRefactoringTestHelper.newInstance(FluxFlatMapUsage.class, getClass())
-        .setFixChooser(FixChoosers.FIRST)
         .addInputLines(
             "A.java",
             "import reactor.core.publisher.Flux;",

error-prone-contrib/src/test/java/tech/picnic/errorprone/bugpatterns/IdentityConversionTest.java

@@ -180,7 +180,6 @@ void identification() {
   @Test
   void replacementFirstSuggestedFix() {
     BugCheckerRefactoringTestHelper.newInstance(IdentityConversion.class, getClass())
-        .setFixChooser(FixChoosers.FIRST)
         .addInputLines(
             "A.java",
             "import static com.google.errorprone.matchers.Matchers.staticMethod;",

error-prone-contrib/src/test/java/tech/picnic/errorprone/bugpatterns/StringCaseLocaleUsageTest.java

@@ -48,7 +48,6 @@ void identification() {
   @Test
   void replacementFirstSuggestedFix() {
     BugCheckerRefactoringTestHelper.newInstance(StringCaseLocaleUsage.class, getClass())
-        .setFixChooser(FixChoosers.FIRST)
         .addInputLines(
             "A.java",
             "class A {",

error-prone-contrib/src/test/java/tech/picnic/errorprone/refasterrules/RefasterRulesTest.java

@@ -35,6 +35,7 @@ final class RefasterRulesTest {
           AssertJThrowingCallableRules.class,
           AssortedRules.class,
           BigDecimalRules.class,
+          BugCheckerRules.class,
           CollectionRules.class,
           ComparatorRules.class,
           DoubleStreamRules.class,

error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/BugCheckerRulesTestInput.java

@@ -0,0 +1,29 @@
+package tech.picnic.errorprone.refasterrules;
+
+import com.google.common.collect.ImmutableSet;
+import com.google.errorprone.BugCheckerRefactoringTestHelper;
+import com.google.errorprone.BugCheckerRefactoringTestHelper.FixChoosers;
+import com.google.errorprone.bugpatterns.BugChecker;
+import tech.picnic.errorprone.refaster.test.RefasterRuleCollectionTestCase;
+
+final class BugCheckerRulesTest implements RefasterRuleCollectionTestCase {
+  @Override
+  public ImmutableSet<?> elidedTypesAndStaticImports() {
+    return ImmutableSet.of(FixChoosers.class);
+  }
+
+  ImmutableSet<BugCheckerRefactoringTestHelper> testBugCheckerRefactoringTestHelperIdentity() {
+    return ImmutableSet.of(
+        BugCheckerRefactoringTestHelper.newInstance(BugChecker.class, getClass())
+            .setFixChooser(FixChoosers.FIRST),
+        BugCheckerRefactoringTestHelper.newInstance(BugChecker.class, getClass())
+            .setImportOrder("static-first"));
+  }
+
+  BugCheckerRefactoringTestHelper
+      testBugCheckerRefactoringTestHelperAddInputLinesExpectUnchanged() {
+    return BugCheckerRefactoringTestHelper.newInstance(BugChecker.class, getClass())
+        .addInputLines("A.java", "class A {}")
+        .addOutputLines("A.java", "class A {}");
+  }
+}

error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/BugCheckerRulesTestOutput.java

@@ -0,0 +1,27 @@
+package tech.picnic.errorprone.refasterrules;
+
+import com.google.common.collect.ImmutableSet;
+import com.google.errorprone.BugCheckerRefactoringTestHelper;
+import com.google.errorprone.BugCheckerRefactoringTestHelper.FixChoosers;
+import com.google.errorprone.bugpatterns.BugChecker;
+import tech.picnic.errorprone.refaster.test.RefasterRuleCollectionTestCase;
+
+final class BugCheckerRulesTest implements RefasterRuleCollectionTestCase {
+  @Override
+  public ImmutableSet<?> elidedTypesAndStaticImports() {
+    return ImmutableSet.of(FixChoosers.class);
+  }
+
+  ImmutableSet<BugCheckerRefactoringTestHelper> testBugCheckerRefactoringTestHelperIdentity() {
+    return ImmutableSet.of(
+        BugCheckerRefactoringTestHelper.newInstance(BugChecker.class, getClass()),
+        BugCheckerRefactoringTestHelper.newInstance(BugChecker.class, getClass()));
+  }
+
+  BugCheckerRefactoringTestHelper
+      testBugCheckerRefactoringTestHelperAddInputLinesExpectUnchanged() {
+    return BugCheckerRefactoringTestHelper.newInstance(BugChecker.class, getClass())
+        .addInputLines("A.java", "class A {}")
+        .expectUnchanged();
+  }
+}