KT-65404 KAPT should print a warning if stub generation is triggered for an interface with method bodies but without -Xjvm-default=all or -Xjvm-default=all-compatibility

Merge-request: KT-MR-14139
Merged-by: Pavel Mikhailovskii <Pavel.Mikhailovskii@jetbrains.com>

plugins/kapt3/kapt3-cli/test/org/jetbrains/kotlin/kapt/cli/test/AbstractKaptToolIntegrationTest.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.kapt.cli.test
 
 import com.intellij.openapi.util.SystemInfo
+import com.intellij.openapi.util.text.StringUtil.convertLineSeparators
 import org.jetbrains.kotlin.cli.common.arguments.readArgumentsFromArgFile
 import org.jetbrains.kotlin.test.services.JUnit5Assertions
 import org.jetbrains.kotlin.test.util.KtTestUtil
@@ -53,10 +54,10 @@ abstract class AbstractKaptToolIntegrationTest {
                     "javac" -> runJavac(section.args)
                     "java" -> runJava(section.args)
                     "output" -> {
-                        val output = File(tmpdir, "processOutput.txt").readText()
-                        val expected = section.content.trim()
-                        JUnit5Assertions.assertTrue(output.contains(expected)) {
-                            "Output\"$output\" doesn't contain the expected string \"$expected\""
+                        val output = convertLineSeparators(File(tmpdir, "processOutput.txt").readText().trim())
+                        val expected = convertLineSeparators(section.content.trim())
+                        JUnit5Assertions.assertEquals(expected, output) {
+                            "Output\"$output\" is different from the expected string \"$expected\""
                         }
                     }
                     "after" -> {}

plugins/kapt3/kapt3-cli/testData/integration-kapt4/defaultMethodsAllCompatibilityNoWarning/Test.kt

@@ -0,0 +1,11 @@
+package test
+
+interface I1 {
+    fun foo() {}
+}
+
+interface I2 {
+    fun bar() {}
+}
+
+class C: I1, I2

plugins/kapt3/kapt3-cli/testData/integration-kapt4/defaultMethodsAllCompatibilityNoWarning/build.txt

@@ -0,0 +1,18 @@
+# mkdir
+output/stubs
+
+# kapt
+-Xjvm-default=all-compatibility
+-language-version 2.0
+-Xuse-kapt4
+-Kapt-mode=stubs
+-Kapt-stubs=output/stubs
+-Kapt-classes=output/classes
+-Kapt-sources=output/sources
+-Kapt-classpath=output/ap
+-d output/classes
+-cp %KOTLIN_STDLIB%
+Test.kt
+
+# output
+warning: k2 kapt is an experimental feature. Use with caution.

plugins/kapt3/kapt3-cli/testData/integration-kapt4/defaultMethodsAllNoWarning/Test.kt

@@ -0,0 +1,11 @@
+package test
+
+interface I1 {
+    fun foo() {}
+}
+
+interface I2 {
+    fun bar() {}
+}
+
+class C: I1, I2

plugins/kapt3/kapt3-cli/testData/integration-kapt4/defaultMethodsAllNoWarning/build.txt

@@ -0,0 +1,18 @@
+# mkdir
+output/stubs
+
+# kapt
+-Xjvm-default=all
+-language-version 2.0
+-Xuse-kapt4
+-Kapt-mode=stubs
+-Kapt-stubs=output/stubs
+-Kapt-classes=output/classes
+-Kapt-sources=output/sources
+-Kapt-classpath=output/ap
+-d output/classes
+-cp %KOTLIN_STDLIB%
+Test.kt
+
+# output
+warning: k2 kapt is an experimental feature. Use with caution.

plugins/kapt3/kapt3-cli/testData/integration-kapt4/defaultMethodsWarning/Test.kt

@@ -0,0 +1,11 @@
+package test
+
+interface I1 {
+    fun foo() {}
+}
+
+interface I2 {
+    fun bar() {}
+}
+
+class C: I1, I2

plugins/kapt3/kapt3-cli/testData/integration-kapt4/defaultMethodsWarning/build.txt

@@ -0,0 +1,18 @@
+# mkdir
+output/stubs
+
+# kapt
+-language-version 2.0
+-Xuse-kapt4
+-Kapt-mode=stubs
+-Kapt-stubs=output/stubs
+-Kapt-classes=output/classes
+-Kapt-sources=output/sources
+-Kapt-classpath=output/ap
+-d output/classes
+-cp %KOTLIN_STDLIB%
+Test.kt
+
+# output
+warning: k2 kapt is an experimental feature. Use with caution.
+warning: [kapt] Support for interface methods with bodies in Kapt requires -Xjvm-default=all or -Xjvm-default=all-compatibility compiler option

plugins/kapt3/kapt3-cli/tests-gen/org/jetbrains/kotlin/kapt/cli/test/Kapt4ToolIntegrationTestGenerated.java

@@ -42,6 +42,24 @@ public class Kapt4ToolIntegrationTestGenerated extends AbstractKapt4ToolIntegrat
         runTest("plugins/kapt3/kapt3-cli/testData/integration-kapt4/correctErrorTypesOn/");
     }
 
+    @Test
+    @TestMetadata("defaultMethodsAllCompatibilityNoWarning")
+    public void testDefaultMethodsAllCompatibilityNoWarning() throws Exception {
+        runTest("plugins/kapt3/kapt3-cli/testData/integration-kapt4/defaultMethodsAllCompatibilityNoWarning/");
+    }
+
+    @Test
+    @TestMetadata("defaultMethodsAllNoWarning")
+    public void testDefaultMethodsAllNoWarning() throws Exception {
+        runTest("plugins/kapt3/kapt3-cli/testData/integration-kapt4/defaultMethodsAllNoWarning/");
+    }
+
+    @Test
+    @TestMetadata("defaultMethodsWarning")
+    public void testDefaultMethodsWarning() throws Exception {
+        runTest("plugins/kapt3/kapt3-cli/testData/integration-kapt4/defaultMethodsWarning/");
+    }
+
     @Test
     @TestMetadata("defaultPackage")
     public void testDefaultPackage() throws Exception {

plugins/kapt4/src/org/jetbrains/kotlin/kapt4/StubGenerator.kt

@@ -10,6 +10,7 @@ package org.jetbrains.kotlin.kapt4
 import com.google.common.collect.HashMultimap
 import com.google.common.collect.Multimap
 import com.intellij.lang.ASTNode
+import com.intellij.lang.jvm.JvmModifier
 import com.intellij.psi.*
 import com.intellij.psi.impl.source.tree.LeafPsiElement
 import org.jetbrains.kotlin.KtNodeTypes
@@ -25,6 +26,8 @@ import org.jetbrains.kotlin.asJava.elements.*
 import org.jetbrains.kotlin.asJava.findFacadeClass
 import org.jetbrains.kotlin.asJava.toLightClass
 import org.jetbrains.kotlin.builtins.StandardNames
+import org.jetbrains.kotlin.config.JvmAnalysisFlags
+import org.jetbrains.kotlin.config.JvmDefaultMode
 import org.jetbrains.kotlin.config.LanguageVersion
 import org.jetbrains.kotlin.diagnostics.PsiDiagnosticUtils.offsetToLineAndColumn
 import org.jetbrains.kotlin.fileClasses.JvmFileClassUtil
@@ -46,6 +49,7 @@ import org.jetbrains.kotlin.utils.toMetadataVersion
 import org.jetbrains.kotlin.kapt3.base.KaptOptions
 import org.jetbrains.kotlin.kapt3.base.util.KaptLogger
 import org.jetbrains.kotlin.kapt3.stubs.MembersPositionComparator
+import org.jetbrains.kotlin.load.java.JvmAbi
 import org.jetbrains.kotlin.psi.psiUtil.children
 import org.jetbrains.kotlin.psi.psiUtil.findDescendantOfType
 import org.jetbrains.kotlin.utils.Printer
@@ -66,8 +70,10 @@ internal fun generateStubs(
             return emptyMap()
         }
     }
+    val jvmDefaultMode = module.languageVersionSettings.getFlag(JvmAnalysisFlags.jvmDefaultMode)
     return analyze(module) {
-        StubGenerator(files.filterIsInstance<KtFile>(), options, logger, metadataRenderer, overriddenMetadataVersion).generateStubs()
+        StubGenerator(files.filterIsInstance<KtFile>(), options, logger, metadataRenderer, overriddenMetadataVersion, jvmDefaultMode)
+            .generateStubs()
     }
 }
 
@@ -85,6 +91,7 @@ private class StubGenerator(
     private val logger: KaptLogger,
     private val metadataRenderer: (Printer.(Metadata) -> Unit)? = null,
     private val overriddenMetadataVersion: BinaryVersion? = null,
+    private val jvmDefaultMode: JvmDefaultMode,
 ) {
     private val strictMode = options[KaptFlag.STRICT]
     private val stripMetadata = options[KaptFlag.STRIP_METADATA]
@@ -513,6 +520,11 @@ private class StubGenerator(
                 if (!(modifierListOwner is PsiMethod && modifierListOwner.isConstructor && modifierListOwner.containingClass?.isEnum == true) && (modifierListOwner !is PsiEnumConstant)) {
                     for (modifier in PsiModifier.MODIFIERS.filter(modifierListOwner::hasModifierProperty)) {
                         if (modifier == PsiModifier.PRIVATE && (modifierListOwner as? PsiMember)?.containingClass?.isInterface == true) continue
+
+                        if (!jvmDefaultMode.isEnabled && modifier == PsiModifier.DEFAULT) {
+                            onError("Support for interface methods with bodies in Kapt requires -Xjvm-default=all or -Xjvm-default=all-compatibility compiler option")
+                        }
+
                         if ((modifier != PsiModifier.FINAL && modifier != PsiModifier.ABSTRACT) || !(modifierListOwner is PsiClass && modifierListOwner.isEnum)) {
                             printWithNoIndent(modifier, " ")
                         }