Fix: formatter no longer adds whitespace to blank lines

changelog/@unreleased/pr-800.v2.yml

@@ -0,0 +1,5 @@
+type: fix
+fix:
+  description: 'Don''t add whitespace to blank lines inside comments. Fixes #799'
+  links:
+  - https://github.com/palantir/gradle-baseline/pull/800

gradle-baseline-java/src/main/groovy/com/palantir/baseline/plugins/BaselineFormat.java

@@ -52,11 +52,12 @@ public void apply(Project project) {
                 java.removeUnusedImports();
                 // use empty string to specify one group for all non-static imports
                 java.importOrder("");
-                java.trimTrailingWhitespace();
 
                 if (eclipseFormattingEnabled(project)) {
                     java.eclipse().configFile(project.file(eclipseXml.toString()));
                 }
+
+                java.trimTrailingWhitespace();
             });
 
             // necessary because SpotlessPlugin creates tasks in an afterEvaluate block
@@ -65,7 +66,7 @@ public void apply(Project project) {
                 Task spotlessJava = project.getTasks().getByName("spotlessJava");
                 Task spotlessApply = project.getTasks().getByName("spotlessApply");
                 if (eclipseFormattingEnabled(project) && !Files.exists(eclipseXml)) {
-                    spotlessJava.dependsOn(project.getTasks().findByPath(":baselineUpdateConfig"));
+                    spotlessJava.dependsOn(":baselineUpdateConfig");
                 }
                 formatTask.dependsOn(spotlessApply);
                 project.getTasks().withType(JavaCompile.class).configureEach(spotlessJava::mustRunAfter);

gradle-baseline-java/src/test/groovy/com/palantir/baseline/BaselineFormatIntegrationTest.groovy

@@ -16,6 +16,8 @@
 
 package com.palantir.baseline
 
+import com.google.common.io.Resources
+import java.nio.charset.Charset
 import org.apache.commons.io.FileUtils
 import org.gradle.testkit.runner.BuildResult
 import org.gradle.testkit.runner.TaskOutcome
@@ -152,4 +154,23 @@ class BaselineFormatIntegrationTest extends AbstractPluginTest {
         BuildResult result = with('spotlessJavaCheck').build()
         result.task(":spotlessJava").outcome == TaskOutcome.SUCCESS
     }
+
+    def 'eclipse format trims blank lines in block or javadoc comment'() {
+        when:
+        buildFile << standardBuildFile
+        file('gradle.properties') << """
+            com.palantir.baseline-format.eclipse=true
+        """.stripIndent()
+        file('src/main/java/test/Test.java').text = resourceAsString("blank-lines-in-comments.java")
+
+        then:
+        BuildResult result = with('format').build()
+        result.task(":spotlessJavaApply").outcome == TaskOutcome.SUCCESS
+        file('src/main/java/test/Test.java').text == resourceAsString("blank-lines-in-comments-fixed.java")
+    }
+
+    private String resourceAsString(String fileName) {
+        Resources.toString(Resources.getResource(this.class, fileName), Charset.defaultCharset())
+    }
+
 }

gradle-baseline-java/src/test/resources/com/palantir/baseline/blank-lines-in-comments-fixed.java

@@ -0,0 +1,19 @@
+package test;
+
+public class Test {
+    /**
+     Docstring that looks like a list:
+
+     1. hey
+     2. there
+
+     with blank line.
+     */
+    Void test() {
+        /*
+        Normal comment
+
+        with blank line.
+        */
+    }
+}

gradle-baseline-java/src/test/resources/com/palantir/baseline/blank-lines-in-comments.java

@@ -0,0 +1,19 @@
+package test;
+
+public class Test {
+    /**
+     Docstring that looks like a list:
+
+     1. hey
+     2. there
+
+     with blank line.
+     */
+    Void test() {
+        /*
+        Normal comment
+
+        with blank line.
+        */
+    }
+}