Fix initialization order in REPL

#KT-6843 Fixed

compiler/backend/src/org/jetbrains/kotlin/codegen/ScriptCodegen.java

@@ -123,7 +123,7 @@ public class ScriptCodegen extends MemberCodegen<JetScript> {
             @NotNull ScriptDescriptor scriptDescriptor,
             @NotNull ClassDescriptor classDescriptorForScript,
             @NotNull ClassBuilder classBuilder,
-            @NotNull final MethodContext methodContext
+            @NotNull MethodContext methodContext
     ) {
         //noinspection ConstantConditions
         Type blockType = typeMapper.mapType(scriptDescriptor.getScriptCodeDescriptor().getReturnType());
@@ -143,7 +143,7 @@ public class ScriptCodegen extends MemberCodegen<JetScript> {
         if (state.getClassBuilderMode() == ClassBuilderMode.FULL) {
             mv.visitCode();
 
-            final InstructionAdapter iv = new InstructionAdapter(mv);
+            InstructionAdapter iv = new InstructionAdapter(mv);
 
             Type classType = typeMapper.mapType(classDescriptorForScript);
 
@@ -152,7 +152,7 @@ public class ScriptCodegen extends MemberCodegen<JetScript> {
 
             iv.load(0, classType);
 
-            final FrameMap frameMap = new FrameMap();
+            FrameMap frameMap = new FrameMap();
             frameMap.enterTemp(OBJECT_TYPE);
 
             for (ScriptDescriptor importedScript : context.getEarlierScripts()) {
@@ -167,13 +167,6 @@ public class ScriptCodegen extends MemberCodegen<JetScript> {
                 frameMap.enter(parameter, argTypes[i + add]);
             }
 
-            generateInitializers(new Function0<ExpressionCodegen>() {
-                @Override
-                public ExpressionCodegen invoke() {
-                    return new ExpressionCodegen(iv, frameMap, Type.VOID_TYPE, methodContext, state, ScriptCodegen.this);
-                }
-            });
-
             int offset = 1;
 
             for (ScriptDescriptor earlierScript : context.getEarlierScripts()) {
@@ -192,9 +185,16 @@ public class ScriptCodegen extends MemberCodegen<JetScript> {
                 iv.putfield(classType.getInternalName(), parameter.getName().getIdentifier(), parameterType.getDescriptor());
             }
 
-            StackValue stackValue =
-                    new ExpressionCodegen(mv, frameMap, Type.VOID_TYPE, methodContext, state, this)
-                            .gen(scriptDeclaration.getBlockExpression());
+            final ExpressionCodegen codegen = new ExpressionCodegen(mv, frameMap, Type.VOID_TYPE, methodContext, state, this);
+
+            generateInitializers(new Function0<ExpressionCodegen>() {
+                @Override
+                public ExpressionCodegen invoke() {
+                    return codegen;
+                }
+            });
+
+            StackValue stackValue = codegen.gen(scriptDeclaration.getBlockExpression());
             if (stackValue.type != Type.VOID_TYPE) {
                 StackValue.Field resultValue = StackValue
                         .field(blockType, classType, ScriptDescriptor.LAST_EXPRESSION_VALUE_FIELD_NAME, false, StackValue.LOCAL_0);

compiler/testData/repl/regressions/kt6843.repl

@@ -0,0 +1,5 @@
+>>> [data] class Person(val name: String)
+>>> var x: String? = "hello"
+>>> val y = x?.let { Person(it) }
+>>> y
+Person(name=hello)

compiler/testData/repl/simpleTwoVals.repl

@@ -0,0 +1,4 @@
+>>> val x = ""
+>>> val y = x
+>>> x == y
+true

compiler/tests/org/jetbrains/kotlin/repl/ReplInterpreterTestGenerated.java

@@ -30,7 +30,7 @@ import java.util.regex.Pattern;
 @SuppressWarnings("all")
 @TestMetadata("compiler/testData/repl")
 @TestDataPath("$PROJECT_ROOT")
-@InnerTestClasses({ReplInterpreterTestGenerated.Classes.class, ReplInterpreterTestGenerated.Multiline.class, ReplInterpreterTestGenerated.Objects.class, ReplInterpreterTestGenerated.PrimitiveTypes.class, ReplInterpreterTestGenerated.Reflection.class})
+@InnerTestClasses({ReplInterpreterTestGenerated.Classes.class, ReplInterpreterTestGenerated.Multiline.class, ReplInterpreterTestGenerated.Objects.class, ReplInterpreterTestGenerated.PrimitiveTypes.class, ReplInterpreterTestGenerated.Reflection.class, ReplInterpreterTestGenerated.Regressions.class})
 @RunWith(JUnit3RunnerWithInners.class)
 public class ReplInterpreterTestGenerated extends AbstractReplInterpreterTest {
     public void testAllFilesPresentInRepl() throws Exception {
@@ -97,6 +97,12 @@ public class ReplInterpreterTestGenerated extends AbstractReplInterpreterTest {
         doTest(fileName);
     }
 
+    @TestMetadata("simpleTwoVals.repl")
+    public void testSimpleTwoVals() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("compiler/testData/repl/simpleTwoVals.repl");
+        doTest(fileName);
+    }
+
     @TestMetadata("syntaxErrors.repl")
     public void testSyntaxErrors() throws Exception {
         String fileName = JetTestUtils.navigationMetadata("compiler/testData/repl/syntaxErrors.repl");
@@ -267,4 +273,19 @@ public class ReplInterpreterTestGenerated extends AbstractReplInterpreterTest {
             doTest(fileName);
         }
     }
+
+    @TestMetadata("compiler/testData/repl/regressions")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class Regressions extends AbstractReplInterpreterTest {
+        public void testAllFilesPresentInRegressions() throws Exception {
+            JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/repl/regressions"), Pattern.compile("^(.+)\\.repl$"), true);
+        }
+
+        @TestMetadata("kt6843.repl")
+        public void testKt6843() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("compiler/testData/repl/regressions/kt6843.repl");
+            doTest(fileName);
+        }
+    }
 }