Add other possible solution for OUTPUT_FILE_VALIDATOR

Signed-off-by: Björn Kautler <Bjoern@Kautler.net>

subprojects/core/src/integTest/groovy/org/gradle/api/tasks/TaskParametersIntegrationTest.groovy

@@ -726,7 +726,7 @@ task someTask(type: SomeTask) {
 
         expect:
         fails "test"
-        failureDescriptionContains(cannotWriteToFile {
+        failureDescriptionContains(cannotWriteFileToDirectory {
             property('output')
                 .file(outputDir)
                 .isNotFile()

subprojects/core/src/main/java/org/gradle/api/internal/tasks/properties/ValidationActions.java

@@ -21,6 +21,7 @@
 import org.gradle.api.internal.GeneratedSubclass;
 import org.gradle.api.internal.tasks.TaskValidationContext;
 import org.gradle.internal.reflect.problems.ValidationProblemId;
+import org.gradle.internal.reflect.validation.PropertyProblemBuilder;
 import org.gradle.internal.typeconversion.UnsupportedNotationException;
 import org.gradle.model.internal.type.ModelType;
 
@@ -84,13 +85,13 @@ public void doValidate(String propertyName, Object value, TaskValidationContext
             validateNotInReservedFileSystemLocation(propertyName, context, file);
             if (file.exists()) {
                 if (file.isDirectory()) {
-                    reportCannotWriteToFile(propertyName, context, "'" + file + "' is not a file");
+                    reportCannotWriteFileToDirectory(propertyName, context, file);
                 }
                 // else, assume we can write to anything that exists and is not a directory
             } else {
                 for (File candidate = file.getParentFile(); candidate != null && !candidate.isDirectory(); candidate = candidate.getParentFile()) {
                     if (candidate.exists() && !candidate.isDirectory()) {
-                        reportCannotWriteToFile(propertyName, context, "'" + file + "' ancestor '" + candidate + "' is not a directory");
+                        reportCannotCreateParentDirectories(propertyName, context, file, candidate);
                         break;
                     }
                 }
@@ -183,18 +184,32 @@ private static void reportFileTreeWithFileRoot(String propertyName, TaskValidati
         );
     }
 
-    private static void reportCannotWriteToFile(String propertyName, TaskValidationContext context, String cause) {
-        context.visitPropertyProblem(problem ->
-            problem.withId(ValidationProblemId.CANNOT_WRITE_OUTPUT)
-                .reportAs(ERROR)
-                .forProperty(propertyName)
-                .withDescription(() -> "is not writable because " + cause)
-                .happensBecause(() -> "Cannot write a file to a location pointing at a directory")
-                .addPossibleSolution(() -> "Configure '" + propertyName + "' to point to a file, not a directory")
-                .documentedAt("validation_problems", "cannot_write_output")
+    private static void reportCannotWriteFileToDirectory(String propertyName, TaskValidationContext context, File file) {
+        context.visitPropertyProblem(problem -> {
+                PropertyProblemBuilder problemBuilder = problem.withId(ValidationProblemId.CANNOT_WRITE_OUTPUT)
+                    .reportAs(ERROR)
+                    .forProperty(propertyName)
+                    .withDescription(() -> "is not writable because '" + file + "' is not a file")
+                    .happensBecause(() -> "Cannot write a file to a location pointing at a directory")
+                    .addPossibleSolution(() -> "Configure '" + propertyName + "' to point to a file, not a directory")
+                    .addPossibleSolution(() -> "Annotate '" + propertyName + "' with @OutputDirectory instead of @OutputFiles")
+                    .documentedAt("validation_problems", "cannot_write_output");
+            }
         );
     }
 
+    private static void reportCannotCreateParentDirectories(String propertyName, TaskValidationContext context, File file, File ancestor) {
+        context.visitPropertyProblem(problem -> {
+                PropertyProblemBuilder problemBuilder = problem.withId(ValidationProblemId.CANNOT_WRITE_OUTPUT)
+                    .reportAs(ERROR)
+                    .forProperty(propertyName)
+                    .withDescription(() -> "is not writable because '" + file + "' ancestor '" + ancestor + "' is not a directory")
+                    .happensBecause(() -> "Cannot create parent directories that are existing as file")
+                    .addPossibleSolution(() -> "Configure '" + propertyName + "' to point to the correct location")
+                    .documentedAt("validation_problems", "cannot_write_output");
+            }
+        );
+    }
 
     private static String actualKindOf(File input) {
         if (input.isFile()) {

subprojects/core/src/test/groovy/org/gradle/api/internal/project/taskfactory/AnnotationProcessingTaskFactoryTest.groovy

@@ -458,7 +458,7 @@ class AnnotationProcessingTaskFactoryTest extends AbstractProjectBuilderSpec imp
 
         then:
         def e = thrown WorkValidationException
-        validateException(task, e, cannotWriteToFile {
+        validateException(task, e, cannotWriteFileToDirectory {
             property('outputFile')
                 .file(task.outputFile)
                 .isNotFile()
@@ -478,7 +478,7 @@ class AnnotationProcessingTaskFactoryTest extends AbstractProjectBuilderSpec imp
 
         then:
         def e = thrown WorkValidationException
-        validateException(task, e, cannotWriteToFile {
+        validateException(task, e, cannotWriteFileToDirectory {
             property('outputFiles')
                 .file(task.outputFiles[0])
                 .isNotFile()
@@ -499,7 +499,7 @@ class AnnotationProcessingTaskFactoryTest extends AbstractProjectBuilderSpec imp
 
         then:
         def e = thrown WorkValidationException
-        validateException(task, e, cannotWriteToFile {
+        validateException(task, e, cannotCreateParentDirectories {
             property('outputFile')
                 .file(task.outputFile)
                 .ancestorIsNotDirectory(task.outputFile.parentFile)
@@ -520,7 +520,7 @@ class AnnotationProcessingTaskFactoryTest extends AbstractProjectBuilderSpec imp
 
         then:
         def e = thrown WorkValidationException
-        validateException(task, e, cannotWriteToFile {
+        validateException(task, e, cannotCreateParentDirectories {
             property('outputFiles')
                 .file(task.outputFiles[0])
                 .ancestorIsNotDirectory(task.outputFiles[0].parentFile)

subprojects/model-core/src/test/groovy/org/gradle/internal/reflect/validation/ValidationMessageCheckerTest.groovy

@@ -563,7 +563,7 @@ Please refer to https://docs.gradle.org/current/userguide/validation_problems.ht
         def ancestor = dummyLocation('/tmp/foo')
 
         when:
-        render cannotWriteToFile {
+        render cannotWriteFileToDirectory {
             type('Writer').property('output')
             file(location)
             isNotFile()
@@ -576,13 +576,15 @@ Type 'Writer' property 'output' is not writable because '${location}' is not a f
 
 Reason: Cannot write a file to a location pointing at a directory.
 
-Possible solution: Configure 'output' to point to a file, not a directory.
+Possible solutions:
+  1. Configure 'output' to point to a file, not a directory.
+  2. Annotate 'output' with @OutputDirectory instead of @OutputFiles.
 
 Please refer to https://docs.gradle.org/current/userguide/validation_problems.html#cannot_write_output for more details about this problem.
 """
 
         when:
-        render cannotWriteToFile {
+        render cannotCreateParentDirectories {
             type('Writer').property('output')
             file(location)
             ancestorIsNotDirectory(ancestor)
@@ -593,9 +595,9 @@ Please refer to https://docs.gradle.org/current/userguide/validation_problems.ht
         outputEquals """
 Type 'Writer' property 'output' is not writable because '${location}' ancestor '${ancestor}' is not a directory.
 
-Reason: Cannot write a file to a location pointing at a directory.
+Reason: Cannot create parent directories that are existing as file.
 
-Possible solution: Configure 'output' to point to a file, not a directory.
+Possible solution: Configure 'output' to point to the correct location.
 
 Please refer to https://docs.gradle.org/current/userguide/validation_problems.html#cannot_write_output for more details about this problem.
 """

subprojects/model-core/src/testFixtures/groovy/org/gradle/internal/reflect/validation/ValidationMessageChecker.groovy

@@ -259,12 +259,26 @@ trait ValidationMessageChecker {
     @ValidationTestFor(
         ValidationProblemId.CANNOT_WRITE_OUTPUT
     )
-    String cannotWriteToFile(@DelegatesTo(value = CannotWriteToFile, strategy = Closure.DELEGATE_FIRST) Closure<?> spec = {}) {
+    String cannotWriteFileToDirectory(@DelegatesTo(value = CannotWriteToFile, strategy = Closure.DELEGATE_FIRST) Closure<?> spec = {}) {
         def config = display(CannotWriteToFile, 'cannot_write_output', spec)
-        config.description("is not writable because '${config.file}' ${config.reason}")
+
+        def cannotWriteToFile = config.description("is not writable because '${config.file}' ${config.reason}")
             .reason("Cannot write a file to a location pointing at a directory")
             .solution("Configure '${config.property}' to point to a file, not a directory")
-            .render()
+            .solution("Annotate '${config.property}' with @OutputDirectory instead of @OutputFiles.")
+        cannotWriteToFile.render()
+    }
+
+    @ValidationTestFor(
+        ValidationProblemId.CANNOT_WRITE_OUTPUT
+    )
+    String cannotCreateParentDirectories(@DelegatesTo(value = CannotWriteToFile, strategy = Closure.DELEGATE_FIRST) Closure<?> spec = {}) {
+        def config = display(CannotWriteToFile, 'cannot_write_output', spec)
+
+        def cannotWriteToFile = config.description("is not writable because '${config.file}' ${config.reason}")
+            .reason("Cannot create parent directories that are existing as file")
+            .solution("Configure '${config.property}' to point to the correct location")
+        cannotWriteToFile.render()
     }
 
     @ValidationTestFor(