Language feature for nullability assertions on enhanced nullability

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/K2JVMCompilerArguments.kt

@@ -106,6 +106,9 @@ class K2JVMCompilerArguments : CommonCompilerArguments() {
     @Argument(value = "-Xno-param-assertions", description = "Don't generate not-null assertions on parameters of methods accessible from Java")
     var noParamAssertions: Boolean by FreezableVar(false)
 
+    @Argument(value = "-Xstrict-java-nullability-assertions", description = "Generate nullability assertions for non-null Java expressions")
+    var strictJavaNullabilityAssertions: Boolean by FreezableVar(false)
+
     @Argument(value = "-Xno-optimize", description = "Disable optimizations")
     var noOptimize: Boolean by FreezableVar(false)
 

compiler/cli/src/org/jetbrains/kotlin/cli/common/CLICompiler.java

@@ -204,6 +204,8 @@ public abstract class CLICompiler<A extends CommonCompilerArguments> extends CLI
             extraLanguageFeatures.put(LanguageFeature.Coroutines, coroutinesState);
         }
 
+        setupPlatformSpecificLanguageFeatureSettings(extraLanguageFeatures, arguments);
+
         CommonConfigurationKeysKt.setLanguageVersionSettings(configuration, new LanguageVersionSettingsImpl(
                 languageVersion,
                 ApiVersion.createByLanguageVersion(apiVersion),
@@ -212,6 +214,13 @@ public abstract class CLICompiler<A extends CommonCompilerArguments> extends CLI
         ));
     }
 
+    protected void setupPlatformSpecificLanguageFeatureSettings(
+            @NotNull Map<LanguageFeature, LanguageFeature.State> extraLanguageFeatures,
+            @NotNull A commandLineArguments
+    ) {
+        // do nothing
+    }
+
     @Nullable
     private static KotlinPaths computeKotlinPaths(@NotNull MessageCollector messageCollector, @NotNull CommonCompilerArguments arguments) {
         KotlinPaths paths;

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/K2JVMCompiler.kt

@@ -228,6 +228,17 @@ class K2JVMCompiler : CLICompiler<K2JVMCompilerArguments>() {
         }
     }
 
+    override fun setupPlatformSpecificLanguageFeatureSettings(
+            extraLanguageFeatures: MutableMap<LanguageFeature, LanguageFeature.State>,
+            commandLineArguments: K2JVMCompilerArguments
+    ) {
+        if (commandLineArguments.strictJavaNullabilityAssertions) {
+            extraLanguageFeatures[LanguageFeature.StrictJavaNullabilityAssertions] = LanguageFeature.State.ENABLED
+        }
+
+        super.setupPlatformSpecificLanguageFeatureSettings(extraLanguageFeatures, commandLineArguments)
+    }
+
     private fun registerJavacIfNeeded(environment: KotlinCoreEnvironment,
                                       arguments: K2JVMCompilerArguments): Boolean {
         if (arguments.useJavac) {
@@ -374,8 +385,6 @@ class K2JVMCompiler : CLICompiler<K2JVMCompilerArguments>() {
             configuration.put(JVMConfigurationKeys.ADD_BUILT_INS_FROM_COMPILER_TO_DEPENDENCIES, arguments.addCompilerBuiltIns)
             configuration.put(JVMConfigurationKeys.CREATE_BUILT_INS_FROM_MODULE_DEPENDENCIES, arguments.loadBuiltInsFromDependencies)
 
-
-
             arguments.declarationsOutputPath?.let { configuration.put(JVMConfigurationKeys.DECLARATIONS_JSON_PATH, it) }
         }
 

compiler/testData/cli/jvm/extraHelp.out

@@ -26,6 +26,8 @@ where advanced options include:
                              Script resolver environment in key-value pairs (the value could be quoted and escaped)
   -Xsingle-module            Combine modules for source files and binary dependencies into a single module
   -Xskip-runtime-version-check Allow Kotlin runtime libraries of incompatible versions in the classpath
+  -Xstrict-java-nullability-assertions
+                             Generate nullability assertions for non-null Java expressions
   -Xuse-javac                Use javac for Java source and class files analysis
   -Xuse-old-class-files-reading Use old class files reading implementation (may slow down the build and should be used in case of problems with the new implementation)
   -Xallow-kotlin-package     Allow compiling code in package 'kotlin' and allow not requiring kotlin.stdlib in module-info

compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt

@@ -74,6 +74,8 @@ enum class LanguageFeature(
     RestrictionOfWrongAnnotationsWithUseSiteTargetsOnTypes(KOTLIN_1_3),
     ProhibitInnerClassesOfGenericClassExtendingThrowable(KOTLIN_1_3),
 
+    StrictJavaNullabilityAssertions(sinceVersion = null, defaultState = State.DISABLED),
+
     // Experimental features
 
     Coroutines(KOTLIN_1_1, ApiVersion.KOTLIN_1_1, "https://kotlinlang.org/docs/diagnostics/experimental-coroutines", State.ENABLED_WITH_WARNING),