SONARKT-302 - stop raising issues on external abstract classes in rul…

…e S6526 after validating on peach (#388)

its/ruling/src/test/resources/expected/kotlin/kotlin/kotlin-S6526.json

@@ -51,50 +51,6 @@
 "kotlin-kotlin-project:sources/kotlin/kotlin/libraries/examples/scripting/jvm-simple-script/script/src/org/jetbrains/kotlin/script/examples/jvm/simple/scriptDef.kt": [
 16
 ],
-"kotlin-kotlin-project:sources/kotlin/kotlin/libraries/stdlib/js/src/org.w3c/org.khronos.webgl.kt": [
-69,
-75,
-81,
-87,
-93,
-99,
-105,
-111
-],
-"kotlin-kotlin-project:sources/kotlin/kotlin/libraries/stdlib/js/src/org.w3c/org.w3c.dom.kt": [
-280,
-335,
-341,
-356,
-543,
-581,
-719
-],
-"kotlin-kotlin-project:sources/kotlin/kotlin/libraries/stdlib/js/src/org.w3c/org.w3c.dom.svg.kt": [
-368,
-371,
-377,
-383,
-389,
-395,
-401,
-436,
-540,
-587,
-615,
-621,
-661,
-667,
-735,
-779,
-782,
-785,
-814,
-817
-],
-"kotlin-kotlin-project:sources/kotlin/kotlin/libraries/stdlib/js/src/org.w3c/org.w3c.xhr.kt": [
-39
-],
 "kotlin-kotlin-project:sources/kotlin/kotlin/libraries/tools/binary-compatibility-validator/src/test/kotlin/cases/companions/companions.kt": [
 13,
 47,

kotlin-checks-test-sources/src/main/files/non-compiling/checks/AbstractClassShouldBeInterfaceCheckSampleNonCompiling.kt

@@ -0,0 +1,6 @@
+package checks
+
+class AbstractClassShouldBeInterfaceCheckSampleNonCompiling {
+
+    external abstract class Foo {} // compliant
+}

sonar-kotlin-checks/src/main/java/org/sonarsource/kotlin/checks/AbstractClassShouldBeInterfaceCheck.kt

@@ -35,7 +35,7 @@ class AbstractClassShouldBeInterfaceCheck : AbstractCheck() {
 
     override fun visitClass(klass: KtClass, context: KotlinFileContext) {
 
-        if (!klass.isAbstract() || klass.isInterface() || klass.extendsClass()) return
+        if (!klass.isAbstract() || klass.isInterface() || klass.extendsClass() || klass.isExternal()) return
 
         val allMethods = klass.collectDescendantsOfType<KtFunction>()
         val allProperties: List<KtProperty> by lazy { klass.collectDescendantsOfType<KtProperty>() }
@@ -51,6 +51,7 @@ class AbstractClassShouldBeInterfaceCheck : AbstractCheck() {
     private fun KtClass.extendsClass(): Boolean {
         return superTypeListEntries.any { it is KtSuperTypeCallEntry }
     }
+    private fun KtClass.isExternal() = hasModifier(KtTokens.EXTERNAL_KEYWORD)
 
     private fun KtDeclaration.isAbstract() = hasModifier(KtTokens.ABSTRACT_KEYWORD)
 

sonar-kotlin-checks/src/test/java/org/sonarsource/kotlin/checks/AbstractClassShouldBeInterfaceCheckTest.kt

@@ -19,4 +19,5 @@
  */
 package org.sonarsource.kotlin.checks
 
-internal class AbstractClassShouldBeInterfaceCheckTest : CheckTest(AbstractClassShouldBeInterfaceCheck())
+internal class AbstractClassShouldBeInterfaceCheckTest : CheckTest(AbstractClassShouldBeInterfaceCheck()),
+    CheckTestNonCompiling by CheckTestNonCompilingImpl(AbstractClassShouldBeInterfaceCheck())

sonar-kotlin-checks/src/test/java/org/sonarsource/kotlin/checks/CheckTestNonCompiling.kt

@@ -0,0 +1,53 @@
+/*
+ * SonarSource Kotlin
+ * Copyright (C) 2018-2023 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package org.sonarsource.kotlin.checks
+
+import org.junit.jupiter.api.Test
+import org.sonarsource.kotlin.api.checks.AbstractCheck
+import org.sonarsource.kotlin.testapi.KotlinVerifier
+import java.nio.file.Paths
+
+private const val NON_COMPILING_TEST_FILE_POSTFIX = "SampleNonCompiling.kt"
+val NON_COMPILING_BASE_DIR = Paths.get("..", "kotlin-checks-test-sources", "src", "main", "files", "non-compiling", "checks")
+
+interface CheckTestNonCompiling {
+    @Test
+    fun `non compiling`()
+}
+
+class CheckTestNonCompilingImpl(
+    val check: AbstractCheck,
+    private val sampleFileNonCompiling: String? = null,
+    private val shouldReport: Boolean = false,
+) : CheckTestNonCompiling {
+    private val checkName = check::class.java.simpleName
+
+
+    override fun `non compiling`() {
+        KotlinVerifier(check) {
+            this.fileName = sampleFileNonCompiling ?: "$checkName$NON_COMPILING_TEST_FILE_POSTFIX"
+            this.baseDir = NON_COMPILING_BASE_DIR
+            this.classpath = emptyList()
+            this.deps = emptyList()
+        }.let {
+            if (this.shouldReport) it.verify() else it.verifyNoIssue()
+        }
+    }
+}