FIR: Add separate local scopes for blocks

compiler/fir/analysis-tests/testData/resolve/expresssions/blockLocalScopes.kt

@@ -0,0 +1,16 @@
+class B {
+    fun append() {}
+}
+
+class A {
+    val message = B()
+
+    fun foo(w: Boolean) {
+        if (w) {
+            val message = ""
+            message.toString()
+        } else {
+            message.append() // message here should relate to the class-level property
+        }
+    }
+}

compiler/fir/analysis-tests/testData/resolve/expresssions/blockLocalScopes.txt

@@ -0,0 +1,32 @@
+FILE: blockLocalScopes.kt
+    public final class B : R|kotlin/Any| {
+        public constructor(): R|B| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final fun append(): R|kotlin/Unit| {
+        }
+
+    }
+    public final class A : R|kotlin/Any| {
+        public constructor(): R|A| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final val message: R|B| = R|/B.B|()
+            public get(): R|B|
+
+        public final fun foo(w: R|kotlin/Boolean|): R|kotlin/Unit| {
+            when () {
+                R|<local>/w| ->  {
+                    lval message: R|kotlin/String| = String()
+                    R|<local>/message|.R|kotlin/Any.toString|()
+                }
+                else ->  {
+                    this@R|/A|.R|/A.message|.R|/B.append|()
+                }
+            }
+
+        }
+
+    }

compiler/fir/analysis-tests/tests/org/jetbrains/kotlin/fir/FirDiagnosticsTestGenerated.java

@@ -909,6 +909,11 @@ public class FirDiagnosticsTestGenerated extends AbstractFirDiagnosticsTest {
             runTest("compiler/fir/analysis-tests/testData/resolve/expresssions/baseQualifier.kt");
         }
 
+        @TestMetadata("blockLocalScopes.kt")
+        public void testBlockLocalScopes() throws Exception {
+            runTest("compiler/fir/analysis-tests/testData/resolve/expresssions/blockLocalScopes.kt");
+        }
+
         @TestMetadata("CallBasedInExpressionGenerator.kt")
         public void testCallBasedInExpressionGenerator() throws Exception {
             runTest("compiler/fir/analysis-tests/testData/resolve/expresssions/CallBasedInExpressionGenerator.kt");

compiler/fir/analysis-tests/tests/org/jetbrains/kotlin/fir/FirDiagnosticsWithLightTreeTestGenerated.java

@@ -909,6 +909,11 @@ public class FirDiagnosticsWithLightTreeTestGenerated extends AbstractFirDiagnos
             runTest("compiler/fir/analysis-tests/testData/resolve/expresssions/baseQualifier.kt");
         }
 
+        @TestMetadata("blockLocalScopes.kt")
+        public void testBlockLocalScopes() throws Exception {
+            runTest("compiler/fir/analysis-tests/testData/resolve/expresssions/blockLocalScopes.kt");
+        }
+
         @TestMetadata("CallBasedInExpressionGenerator.kt")
         public void testCallBasedInExpressionGenerator() throws Exception {
             runTest("compiler/fir/analysis-tests/testData/resolve/expresssions/CallBasedInExpressionGenerator.kt");

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/body/resolve/FirBodyResolveTransformer.kt

@@ -39,7 +39,7 @@ open class FirBodyResolveTransformer(
     final override val components: BodyResolveTransformerComponents =
         BodyResolveTransformerComponents(session, scopeSession, this, context)
 
-    private val expressionsTransformer = FirExpressionsResolveTransformer(this)
+    internal val expressionsTransformer = FirExpressionsResolveTransformer(this)
     protected open val declarationsTransformer = FirDeclarationsResolveTransformer(this)
     private val controlFlowStatementsTransformer = FirControlFlowStatementsResolveTransformer(this)
 

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/body/resolve/FirControlFlowStatementsResolveTransformer.kt

@@ -40,10 +40,17 @@ class FirControlFlowStatementsResolveTransformer(transformer: FirBodyResolveTran
     }
 
     override fun transformDoWhileLoop(doWhileLoop: FirDoWhileLoop, data: ResolutionMode): CompositeTransformResult<FirStatement> {
-        return doWhileLoop.also(dataFlowAnalyzer::enterDoWhileLoop)
+        // Do-while has a specific scope structure (its block and condition effectively share the scope)
-            .transformBlock(transformer, data).also(dataFlowAnalyzer::enterDoWhileLoopCondition)
+        return withNewLocalScope {
-            .transformCondition(transformer, data).also(dataFlowAnalyzer::exitDoWhileLoop)
+            doWhileLoop.also(dataFlowAnalyzer::enterDoWhileLoop)
-            .transformOtherChildren(transformer, data).compose()
+                .apply {
+                    transformer.expressionsTransformer.transformBlockInCurrentScope(block, data)
+                    dataFlowAnalyzer
+                }
+                .also(dataFlowAnalyzer::enterDoWhileLoopCondition).transformCondition(transformer, data)
+                .also(dataFlowAnalyzer::exitDoWhileLoop)
+                .transformOtherChildren(transformer, data).compose()
+        }
     }
 
     // ------------------------------- When expressions -------------------------------

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/body/resolve/FirExpressionsResolveTransformer.kt

@@ -191,6 +191,14 @@ class FirExpressionsResolveTransformer(transformer: FirBodyResolveTransformer) :
     }
 
     override fun transformBlock(block: FirBlock, data: ResolutionMode): CompositeTransformResult<FirStatement> {
+        withNewLocalScope {
+            transformBlockInCurrentScope(block, data)
+        }
+
+        return block.compose()
+    }
+
+    internal fun transformBlockInCurrentScope(block: FirBlock, data: ResolutionMode) {
         dataFlowAnalyzer.enterBlock(block)
         val numberOfStatements = block.statements.size
 
@@ -220,8 +228,8 @@ class FirExpressionsResolveTransformer(transformer: FirBodyResolveTransformer) :
                 diagnostic = ConeSimpleDiagnostic("No type for block", DiagnosticKind.InferenceError)
             }
         }
+
         dataFlowAnalyzer.exitBlock(block)
-        return block.compose()
     }
 
     override fun transformThisReceiverExpression(

compiler/testData/codegen/box/functions/localFunctions/nameClashAcrossDifferentContainers.kt

@@ -1,5 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
-
 var result = ""
 
 fun overload() {

compiler/testData/diagnostics/tests/controlFlowAnalysis/initializationInLambda.fir.kt

@@ -70,8 +70,8 @@ class Your {
 val z = if (true) {
     val xx: Int
     exec {
-        <!UNRESOLVED_REFERENCE!>xx<!> = 24
+        xx = 24
     }
     42
 }
-else 0
+else 0