FIR2IR insert implicit cast on elvis RHS

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt

@@ -292,14 +292,22 @@ class Fir2IrVisitor(
         )
         if (initializer != null) {
             irVariable.initializer =
-                with(implicitCastInserter) {
+                convertToIrExpression(initializer)
-                    convertToIrExpression(initializer).cast(initializer, initializer.typeRef, variable.returnTypeRef)
+                    .insertImplicitCast(initializer, initializer.typeRef, variable.returnTypeRef)
-                }
         }
         annotationGenerator.generate(irVariable, variable)
         return irVariable
     }
 
+    private fun IrExpression.insertImplicitCast(
+        baseExpression: FirExpression,
+        valueType: FirTypeRef,
+        expectedType: FirTypeRef
+    ) =
+        with(implicitCastInserter) {
+            this@insertImplicitCast.cast(baseExpression, valueType, expectedType)
+        }
+
     override fun visitProperty(property: FirProperty, data: Any?): IrElement {
         if (property.isLocal) return visitLocalVariable(property)
         val irProperty = declarationStorage.getCachedIrProperty(property)!!
@@ -707,13 +715,15 @@ class Fir2IrVisitor(
             val notNullType = originalType.withNullability(ConeNullability.NOT_NULL, session.typeContext)
             val irBranches = listOf(
                 IrBranchImpl(
-                    startOffset, endOffset, primitiveOp2(
+                    startOffset, endOffset,
+                    primitiveOp2(
                         startOffset, endOffset, irBuiltIns.eqeqSymbol,
                         irBuiltIns.booleanType, IrStatementOrigin.EQEQ,
                         irGetLhsValue(),
                         IrConstImpl.constNull(startOffset, endOffset, irBuiltIns.nothingNType)
                     ),
                     convertToIrExpression(elvisExpression.rhs)
+                        .insertImplicitCast(elvisExpression, elvisExpression.rhs.typeRef, elvisExpression.typeRef)
                 ),
                 IrElseBranchImpl(
                     IrConstImpl.boolean(startOffset, endOffset, irBuiltIns.booleanType, true),
@@ -815,9 +825,7 @@ class Fir2IrVisitor(
     private fun FirWhenBranch.toIrWhenBranch(whenExpressionType: FirTypeRef): IrBranch {
         return convertWithOffsets { startOffset, endOffset ->
             val condition = condition
-            val irResult = with(implicitCastInserter) {
+            val irResult = convertToIrExpression(result).insertImplicitCast(result, result.typeRef, whenExpressionType)
-                convertToIrExpression(result).cast(result, result.typeRef, whenExpressionType)
-            }
             if (condition is FirElseIfTrueCondition) {
                 IrElseBranchImpl(IrConstImpl.boolean(irResult.startOffset, irResult.endOffset, irBuiltIns.booleanType, true), irResult)
             } else {

compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/ir/Fir2IrTextTestGenerated.java

@@ -2901,6 +2901,12 @@ public class Fir2IrTextTestGenerated extends AbstractFir2IrTextTest {
                 runTest("compiler/testData/ir/irText/types/nullChecks/implicitNotNullOnPlatformType.kt");
             }
 
+            @Test
+            @TestMetadata("nullCheckInElvisRhs.kt")
+            public void testNullCheckInElvisRhs() throws Exception {
+                runTest("compiler/testData/ir/irText/types/nullChecks/nullCheckInElvisRhs.kt");
+            }
+
             @Test
             @TestMetadata("nullCheckOnInterfaceDelegation.kt")
             public void testNullCheckOnInterfaceDelegation() throws Exception {

compiler/testData/codegen/box/notNullAssertions/rightElvisOperand.kt

@@ -1,6 +1,4 @@
 // TARGET_BACKEND: JVM
-// IGNORE_BACKEND_FIR: JVM_IR
-// FIR status: Fail: should have been an exception in 'bar()'
 // MODULE: lib
 // FILE: RightElvisOperand.java
 

compiler/testData/ir/irText/types/nullChecks/nullCheckInElvisRhs.fir.ir.txt

@@ -0,0 +1,23 @@
+Module: lib
+Module: main
+FILE fqName:<root> fileName:/nullCheckInElvisRhs.kt
+  FUN name:baz visibility:public modality:FINAL <> () returnType:kotlin.String?
+    BLOCK_BODY
+      RETURN type=kotlin.Nothing from='public final fun baz (): kotlin.String? declared in <root>'
+        CONST Null type=kotlin.Nothing? value=null
+  FUN name:test visibility:public modality:FINAL <> () returnType:kotlin.String
+    BLOCK_BODY
+      RETURN type=kotlin.Nothing from='public final fun test (): kotlin.String declared in <root>'
+        BLOCK type=kotlin.String origin=ELVIS
+          VAR IR_TEMPORARY_VARIABLE name:tmp_0 type:kotlin.String? [val]
+            CALL 'public final fun baz (): kotlin.String? declared in <root>' type=kotlin.String? origin=null
+          WHEN type=kotlin.String origin=ELVIS
+            BRANCH
+              if: CALL 'public final fun EQEQ (arg0: kotlin.Any?, arg1: kotlin.Any?): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=EQEQ
+                arg0: GET_VAR 'val tmp_0: kotlin.String? [val] declared in <root>.test' type=kotlin.String? origin=null
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: TYPE_OP type=kotlin.String origin=IMPLICIT_NOTNULL typeOperand=kotlin.String
+                CALL 'public/*package*/ open fun foo (): @[FlexibleNullability] kotlin.String? declared in <root>.RightElvisOperand' type=@[FlexibleNullability] kotlin.String? origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value=true
+              then: GET_VAR 'val tmp_0: kotlin.String? [val] declared in <root>.test' type=kotlin.String? origin=null

compiler/testData/ir/irText/types/nullChecks/nullCheckInElvisRhs.fir.kt.txt

@@ -0,0 +1,17 @@
+// MODULE: lib
+// MODULE: main
+// FILE: nullCheckInElvisRhs.kt
+
+fun baz(): String? {
+  return null
+}
+
+fun test(): String {
+  return { // BLOCK
+    val <elvis>: String? = baz()
+    when {
+      EQEQ(arg0 = <elvis>, arg1 = null) -> foo() /*!! String */
+      else -> <elvis>
+    }
+  }
+}

compiler/testData/ir/irText/types/nullChecks/nullCheckInElvisRhs.ir.txt

@@ -0,0 +1,23 @@
+Module: lib
+Module: main
+FILE fqName:<root> fileName:/nullCheckInElvisRhs.kt
+  FUN name:baz visibility:public modality:FINAL <> () returnType:kotlin.String?
+    BLOCK_BODY
+      RETURN type=kotlin.Nothing from='public final fun baz (): kotlin.String? declared in <root>'
+        CONST Null type=kotlin.Nothing? value=null
+  FUN name:test visibility:public modality:FINAL <> () returnType:kotlin.String
+    BLOCK_BODY
+      RETURN type=kotlin.Nothing from='public final fun test (): kotlin.String declared in <root>'
+        BLOCK type=kotlin.String origin=ELVIS
+          VAR IR_TEMPORARY_VARIABLE name:tmp_0 type:kotlin.String? [val]
+            CALL 'public final fun baz (): kotlin.String? declared in <root>' type=kotlin.String? origin=null
+          WHEN type=kotlin.String origin=null
+            BRANCH
+              if: CALL 'public final fun EQEQ (arg0: kotlin.Any?, arg1: kotlin.Any?): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=EQEQ
+                arg0: GET_VAR 'val tmp_0: kotlin.String? [val] declared in <root>.test' type=kotlin.String? origin=null
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: TYPE_OP type=kotlin.String origin=IMPLICIT_NOTNULL typeOperand=kotlin.String
+                CALL 'public/*package*/ open fun foo (): @[FlexibleNullability] kotlin.String? declared in <root>.RightElvisOperand' type=@[FlexibleNullability] kotlin.String? origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value=true
+              then: GET_VAR 'val tmp_0: kotlin.String? [val] declared in <root>.test' type=kotlin.String? origin=null

compiler/testData/ir/irText/types/nullChecks/nullCheckInElvisRhs.kt

@@ -0,0 +1,17 @@
+// TARGET_BACKEND: JVM
+
+// MODULE: lib
+// FILE: RightElvisOperand.java
+
+class RightElvisOperand {
+    static String foo() {
+        return null;
+    }
+}
+
+// MODULE: main(lib)
+// FILE: nullCheckInElvisRhs.kt
+
+fun baz(): String? = null
+
+fun test(): String = baz() ?: RightElvisOperand.foo()

compiler/testData/ir/irText/types/nullChecks/nullCheckInElvisRhs.kt.txt

@@ -0,0 +1,18 @@
+// MODULE: lib
+// MODULE: main
+// FILE: nullCheckInElvisRhs.kt
+
+fun baz(): String? {
+  return null
+}
+
+fun test(): String {
+  return { // BLOCK
+    val tmp0_elvis_lhs: String? = baz()
+    when {
+      EQEQ(arg0 = tmp0_elvis_lhs, arg1 = null) -> foo() /*!! String */
+      else -> tmp0_elvis_lhs
+    }
+  }
+}
+

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ir/IrTextTestGenerated.java

@@ -2901,6 +2901,12 @@ public class IrTextTestGenerated extends AbstractIrTextTest {
                 runTest("compiler/testData/ir/irText/types/nullChecks/implicitNotNullOnPlatformType.kt");
             }
 
+            @Test
+            @TestMetadata("nullCheckInElvisRhs.kt")
+            public void testNullCheckInElvisRhs() throws Exception {
+                runTest("compiler/testData/ir/irText/types/nullChecks/nullCheckInElvisRhs.kt");
+            }
+
             @Test
             @TestMetadata("nullCheckOnInterfaceDelegation.kt")
             public void testNullCheckOnInterfaceDelegation() throws Exception {