Check that subject expression is evaluated only once

compiler/testData/codegen/box/when/whenSubjectVariable/subjectExpressionIsEvaluatedOnce.kt

@@ -0,0 +1,22 @@
+// !LANGUAGE: +VariableDeclarationInWhenSubject
+// IGNORE_BACKEND: JS
+
+var effectCount = 0
+
+fun withSideEffect(): Any {
+    effectCount++
+    return 42
+}
+
+fun box(): String {
+    when (val y = withSideEffect()) {
+        1 -> throw AssertionError()
+        "" -> throw AssertionError()
+        is String -> throw AssertionError()
+        42 -> {}
+    }
+
+    if (effectCount != 1) throw AssertionError("effectCount=$effectCount")
+
+    return "OK"
+}

compiler/tests-ir-jvm/tests/org/jetbrains/kotlin/codegen/ir/IrBlackBoxCodegenTestGenerated.java

@@ -21708,6 +21708,11 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
                 runTest("compiler/testData/codegen/box/when/whenSubjectVariable/sparseIntSwitchWithSubjectVariable.kt");
             }
 
+            @TestMetadata("subjectExpressionIsEvaluatedOnce.kt")
+            public void testSubjectExpressionIsEvaluatedOnce() throws Exception {
+                runTest("compiler/testData/codegen/box/when/whenSubjectVariable/subjectExpressionIsEvaluatedOnce.kt");
+            }
+
             @TestMetadata("whenByEnum.kt")
             public void testWhenByEnum() throws Exception {
                 runTest("compiler/testData/codegen/box/when/whenSubjectVariable/whenByEnum.kt");

compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java

@@ -21708,6 +21708,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
                 runTest("compiler/testData/codegen/box/when/whenSubjectVariable/sparseIntSwitchWithSubjectVariable.kt");
             }
 
+            @TestMetadata("subjectExpressionIsEvaluatedOnce.kt")
+            public void testSubjectExpressionIsEvaluatedOnce() throws Exception {
+                runTest("compiler/testData/codegen/box/when/whenSubjectVariable/subjectExpressionIsEvaluatedOnce.kt");
+            }
+
             @TestMetadata("whenByEnum.kt")
             public void testWhenByEnum() throws Exception {
                 runTest("compiler/testData/codegen/box/when/whenSubjectVariable/whenByEnum.kt");

compiler/tests/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java

@@ -21708,6 +21708,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
                 runTest("compiler/testData/codegen/box/when/whenSubjectVariable/sparseIntSwitchWithSubjectVariable.kt");
             }
 
+            @TestMetadata("subjectExpressionIsEvaluatedOnce.kt")
+            public void testSubjectExpressionIsEvaluatedOnce() throws Exception {
+                runTest("compiler/testData/codegen/box/when/whenSubjectVariable/subjectExpressionIsEvaluatedOnce.kt");
+            }
+
             @TestMetadata("whenByEnum.kt")
             public void testWhenByEnum() throws Exception {
                 runTest("compiler/testData/codegen/box/when/whenSubjectVariable/whenByEnum.kt");

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/IrJsCodegenBoxTestGenerated.java

@@ -20723,6 +20723,11 @@ public class IrJsCodegenBoxTestGenerated extends AbstractIrJsCodegenBoxTest {
                 runTest("compiler/testData/codegen/box/when/whenSubjectVariable/sparseIntSwitchWithSubjectVariable.kt");
             }
 
+            @TestMetadata("subjectExpressionIsEvaluatedOnce.kt")
+            public void testSubjectExpressionIsEvaluatedOnce() throws Exception {
+                runTest("compiler/testData/codegen/box/when/whenSubjectVariable/subjectExpressionIsEvaluatedOnce.kt");
+            }
+
             @TestMetadata("whenByEnum.kt")
             public void testWhenByEnum() throws Exception {
                 runTest("compiler/testData/codegen/box/when/whenSubjectVariable/whenByEnum.kt");

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/JsCodegenBoxTestGenerated.java

@@ -19601,6 +19601,11 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
                 runTest("compiler/testData/codegen/box/when/whenSubjectVariable/sparseIntSwitchWithSubjectVariable.kt");
             }
 
+            @TestMetadata("subjectExpressionIsEvaluatedOnce.kt")
+            public void testSubjectExpressionIsEvaluatedOnce() throws Exception {
+                runTest("compiler/testData/codegen/box/when/whenSubjectVariable/subjectExpressionIsEvaluatedOnce.kt");
+            }
+
             @TestMetadata("whenByEnum.kt")
             public void testWhenByEnum() throws Exception {
                 runTest("compiler/testData/codegen/box/when/whenSubjectVariable/whenByEnum.kt");