[FIR] Add VARIABLE_WITH_NO_TYPE_NO_INITIALIZER diagnostic

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/diagnostics/FirDiagnostics.kt

@@ -10,6 +10,7 @@ import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.declarations.Deprecation
 import org.jetbrains.kotlin.fir.declarations.FirCallableDeclaration
 import org.jetbrains.kotlin.fir.declarations.FirRegularClass
+import org.jetbrains.kotlin.fir.declarations.FirVariable
 import org.jetbrains.kotlin.fir.diagnostics.ConeDiagnostic
 import org.jetbrains.kotlin.fir.render
 import org.jetbrains.kotlin.fir.resolve.calls.Candidate
@@ -152,6 +153,10 @@ class ConeDeprecated(val source: FirSourceElement?, val symbol: FirBasedSymbol<*
     override val reason: String get() = "Deprecated: ${deprecation.message}"
 }
 
+class ConeLocalVariableNoTypeOrInitializer(val variable: FirVariable) : ConeDiagnostic() {
+    override val reason: String get() = "Cannot infer variable type without initializer / getter / delegate"
+}
+
 private fun describeSymbol(symbol: FirBasedSymbol<*>): String {
     return when (symbol) {
         is FirClassLikeSymbol<*> -> symbol.classId.asString()

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

@@ -28,6 +28,7 @@ import org.jetbrains.kotlin.fir.resolve.calls.FirNamedReferenceWithCandidate
 import org.jetbrains.kotlin.fir.resolve.constructFunctionalTypeRef
 import org.jetbrains.kotlin.fir.resolve.dfa.FirControlFlowGraphReferenceImpl
 import org.jetbrains.kotlin.fir.resolve.dfa.unwrapSmartcastExpression
+import org.jetbrains.kotlin.fir.resolve.diagnostics.ConeLocalVariableNoTypeOrInitializer
 import org.jetbrains.kotlin.fir.resolve.inference.extractLambdaInfoFromFunctionalType
 import org.jetbrains.kotlin.fir.resolve.inference.isSuspendFunctionType
 import org.jetbrains.kotlin.fir.resolve.mode
@@ -841,10 +842,8 @@ open class FirDeclarationsResolveTransformer(transformer: FirBodyResolveTransfor
                     transformer,
                     withExpectedType(
                         buildErrorTypeRef {
-                            diagnostic = ConeSimpleDiagnostic(
-                                "Cannot infer variable type without initializer / getter / delegate",
-                                DiagnosticKind.InferenceError,
-                            )
+                            diagnostic = ConeLocalVariableNoTypeOrInitializer(variable)
+                            source = variable.source
                         },
                     )
                 )