[kotlin] erroneous error on kotlin injections in foreign languages

^KTIJ-32613 fixed


IJ-CR-192902


(cherry picked from commit f87c8ea0c39924653b3de96de25494c9311963e7)

IJ-CR-192960

GitOrigin-RevId: ea9ffd57379215e98a6da6f65d1ddadfefe6b5ac

plugins/kotlin/highlighting/highlighting-k2/resources/intellij.kotlin.highlighting.xml

@@ -20,6 +20,7 @@
     <highlightVisitor implementation="org.jetbrains.kotlin.idea.highlighting.visitor.KotlinDiagnosticHighlightVisitor"/>
     <highlightVisitor implementation="org.jetbrains.kotlin.idea.highlighting.visitor.KotlinUnusedDeclarationHighlightingVisitor"/>
     <highlightVisitor implementation="org.jetbrains.kotlin.idea.highlighting.visitor.KotlinUnresolvedKDocHighlightVisitor"/>
+    <highlightErrorFilter implementation="org.jetbrains.kotlin.idea.highlighting.visitor.KotlinHighlightInjectionErrorFilter"/>
 
     <highlightUsagesHandlerFactory implementation="org.jetbrains.kotlin.idea.highlighting.KotlinHighlightExitPointsHandlerFactory"/>
 

plugins/kotlin/highlighting/highlighting-k2/src/org/jetbrains/kotlin/idea/highlighting/visitor/KotlinHighlightInjectionErrorFilter.kt

@@ -0,0 +1,19 @@
+// Copyright 2000-2026 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package org.jetbrains.kotlin.idea.highlighting.visitor
+
+import com.intellij.codeInsight.highlighting.HighlightErrorFilter
+import com.intellij.lang.injection.InjectedLanguageManager
+import com.intellij.psi.PsiErrorElement
+import org.jetbrains.kotlin.idea.KotlinLanguage
+
+internal class KotlinHighlightInjectionErrorFilter: HighlightErrorFilter() {
+    override fun shouldHighlightErrorElement(element: PsiErrorElement): Boolean {
+        if (element.language == KotlinLanguage.INSTANCE &&
+            element.errorDescription == "Package directive and imports are forbidden in code fragments" &&
+            InjectedLanguageManager.getInstance(element.project).isInjectedFragment(element.containingFile)
+        ) {
+            return false
+        }
+        return true
+    }
+}

plugins/kotlin/injection/k2/tests/test/org/jetbrains/kotlin/idea/k2/injection/K2KotlinInjectionTest.kt

@@ -68,4 +68,24 @@ class K2KotlinInjectionTest: KotlinInjectionTestBase() {
             myFixture.checkHighlighting()
         }
     }
+
+    fun testInjectKotlinInJava() {
+        myFixture.configureByText(
+            "a.java",
+            """
+                
+                import org.intellij.lang.annotations.Language;
+                
+                class Main {
+                  {
+                     @Language("kotlin")
+                     var kotlinCode = "package foo; class A"; 
+                  }
+                }
+            """.trimIndent()
+        )
+
+        myFixture.checkHighlighting()
+
+    }
 }