[FIR] Add ILLEGAL_INLINE_PARAMETER_MODIFIER diagnostic

compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/diagnostics/FirDiagnosticsList.kt

@@ -1188,6 +1188,8 @@ object DIAGNOSTICS_LIST : DiagnosticList("FirErrors") {
         val REIFIED_TYPE_PARAMETER_IN_OVERRIDE by error<KtElement>(PositioningStrategy.REIFIED_MODIFIER)
 
         val INLINE_PROPERTY_WITH_BACKING_FIELD by error<KtDeclaration>(PositioningStrategy.DECLARATION_SIGNATURE)
+
+        val ILLEGAL_INLINE_PARAMETER_MODIFIER by error<KtElement>(PositioningStrategy.INLINE_PARAMETER_MODIFIER)
     }
 
     val IMPORTS by object : DiagnosticGroup("Imports") {

compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/diagnostics/model/RegularDiagnosticData.kt

@@ -99,6 +99,7 @@ enum class PositioningStrategy(private val strategy: String? = null) {
     INCOMPATIBLE_DECLARATION,
     ACTUAL_DECLARATION_NAME,
     UNREACHABLE_CODE,
+    INLINE_PARAMETER_MODIFIER,
 
     ;
 

compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrors.kt

@@ -614,6 +614,7 @@ object FirErrors {
     val INVALID_DEFAULT_FUNCTIONAL_PARAMETER_FOR_INLINE by error2<KtElement, FirExpression, FirValueParameterSymbol>()
     val REIFIED_TYPE_PARAMETER_IN_OVERRIDE by error0<KtElement>(SourceElementPositioningStrategies.REIFIED_MODIFIER)
     val INLINE_PROPERTY_WITH_BACKING_FIELD by error0<KtDeclaration>(SourceElementPositioningStrategies.DECLARATION_SIGNATURE)
+    val ILLEGAL_INLINE_PARAMETER_MODIFIER by error0<KtElement>(SourceElementPositioningStrategies.INLINE_PARAMETER_MODIFIER)
 
     // Imports
     val CANNOT_ALL_UNDER_IMPORT_FROM_SINGLETON by error1<KtImportDirective, Name>(SourceElementPositioningStrategies.IMPORT_LAST_NAME)

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirInlineDeclarationChecker.kt

@@ -11,6 +11,7 @@ import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.fir.*
 import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
 import org.jetbrains.kotlin.fir.analysis.checkers.context.PersistentCheckerContext
+import org.jetbrains.kotlin.fir.analysis.checkers.getModifier
 import org.jetbrains.kotlin.fir.analysis.checkers.isInlineOnly
 import org.jetbrains.kotlin.fir.analysis.checkers.unsubstitutedScope
 import org.jetbrains.kotlin.fir.analysis.checkers.util.checkChildrenWithCustomVisitor
@@ -38,7 +39,10 @@ import org.jetbrains.kotlin.util.OperatorNameConventions
 
 object FirInlineDeclarationChecker : FirFunctionChecker() {
     override fun check(declaration: FirFunction, context: CheckerContext, reporter: DiagnosticReporter) {
-        if (!declaration.isInline) return
+        if (!declaration.isInline) {
+            checkParametersInNotInline(declaration, context, reporter)
+            return
+        }
         // local inline functions are prohibited
         if (declaration.isLocalMember) {
             reporter.reportOn(declaration.source, FirErrors.NOT_YET_SUPPORTED_IN_INLINE, "Local inline functions", context)
@@ -341,12 +345,18 @@ object FirInlineDeclarationChecker : FirFunctionChecker() {
         reporter: DiagnosticReporter
     ) {
         for (param in function.valueParameters) {
-            if (param.isNoinline) continue
-
             val coneType = param.returnTypeRef.coneType
             val isFunctionalType = coneType.isFunctionalType(context.session)
+            val isSuspendFunctionalType = coneType.isSuspendFunctionType(context.session)
             val defaultValue = param.defaultValue
-            if (function.isSuspend && defaultValue != null && coneType.isSuspendFunctionType(context.session)) {
+
+            if (!(isFunctionalType || isSuspendFunctionalType) && (param.isNoinline || param.isCrossinline)) {
+                reporter.reportOn(param.source, FirErrors.ILLEGAL_INLINE_PARAMETER_MODIFIER, context)
+            }
+
+            if (param.isNoinline) continue
+
+            if (function.isSuspend && defaultValue != null && isSuspendFunctionalType) {
                 reporter.reportOn(
                     param.source,
                     FirErrors.NOT_YET_SUPPORTED_IN_INLINE,
@@ -403,6 +413,14 @@ object FirInlineDeclarationChecker : FirFunctionChecker() {
         }
     }
 
+    private fun checkParametersInNotInline(function: FirFunction, context: CheckerContext, reporter: DiagnosticReporter) {
+        for (param in function.valueParameters) {
+            if (param.isNoinline || param.isCrossinline) {
+                reporter.reportOn(param.source, FirErrors.ILLEGAL_INLINE_PARAMETER_MODIFIER, context)
+            }
+        }
+    }
+
     private fun FirCallableDeclaration.getOverriddenSymbols(context: CheckerContext): List<FirCallableSymbol<out FirCallableDeclaration>> {
         if (!this.isOverride) return emptyList()
         val classSymbol = this.containingClass()?.toSymbol(context.session) as? FirClassSymbol<*> ?: return emptyList()

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDefaultErrorMessages.kt

@@ -190,6 +190,7 @@ import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.GENERIC_THROWABLE
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.GETTER_VISIBILITY_DIFFERS_FROM_PROPERTY_VISIBILITY
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.HAS_NEXT_FUNCTION_AMBIGUITY
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.ILLEGAL_CONST_EXPRESSION
+import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.ILLEGAL_INLINE_PARAMETER_MODIFIER
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.ILLEGAL_KOTLIN_VERSION_STRING_VALUE
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.ILLEGAL_RESTRICTED_SUSPENDING_FUNCTION_CALL
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.ILLEGAL_SELECTOR
@@ -1515,6 +1516,8 @@ class FirDefaultErrorMessages {
 
             map.put(SUPER_CALL_FROM_PUBLIC_INLINE, "Accessing super members from public-API inline function is deprecated", SYMBOL)
 
+            map.put(ILLEGAL_INLINE_PARAMETER_MODIFIER, "Modifier is allowed only for function parameters of an inline function")
+
             //imports
             map.put(
                 CANNOT_ALL_UNDER_IMPORT_FROM_SINGLETON,

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/LightTreePositioningStrategies.kt

@@ -358,6 +358,9 @@ object LightTreePositioningStrategies {
     val DATA_MODIFIER: LightTreePositioningStrategy =
         ModifierSetBasedLightTreePositioningStrategy(TokenSet.create(KtTokens.DATA_KEYWORD))
 
+    val INLINE_PARAMETER_MODIFIER: LightTreePositioningStrategy =
+        ModifierSetBasedLightTreePositioningStrategy(TokenSet.create(KtTokens.NOINLINE_KEYWORD, KtTokens.CROSSINLINE_KEYWORD))
+
     val OPERATOR: LightTreePositioningStrategy = object : LightTreePositioningStrategy() {
         override fun mark(
             node: LighterASTNode,

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/SourceElementPositioningStrategies.kt

@@ -286,4 +286,9 @@ object SourceElementPositioningStrategies {
         LightTreePositioningStrategies.NOT_SUPPORTED_IN_INLINE_MOST_RELEVANT,
         PositioningStrategies.NOT_SUPPORTED_IN_INLINE_MOST_RELEVANT
     )
+
+    val INLINE_PARAMETER_MODIFIER = SourceElementPositioningStrategy(
+        LightTreePositioningStrategies.INLINE_PARAMETER_MODIFIER,
+        PositioningStrategies.INLINE_PARAMETER_MODIFIER
+    )
 }

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/PositioningStrategies.kt

@@ -496,6 +496,10 @@ object PositioningStrategies {
     val INNER_MODIFIER: PositioningStrategy<KtModifierListOwner> =
         ModifierSetBasedPositioningStrategy(TokenSet.create(KtTokens.INNER_KEYWORD))
 
+    @JvmField
+    val INLINE_PARAMETER_MODIFIER: PositioningStrategy<KtModifierListOwner> =
+        ModifierSetBasedPositioningStrategy(TokenSet.create(KtTokens.NOINLINE_KEYWORD, KtTokens.CROSSINLINE_KEYWORD))
+
     @JvmField
     val VARIANCE_IN_PROJECTION: PositioningStrategy<KtTypeProjection> = object : PositioningStrategy<KtTypeProjection>() {
         override fun mark(element: KtTypeProjection): List<TextRange> {

compiler/testData/diagnostics/tests/modifiers/inlineParameters.fir.kt

@@ -1,20 +0,0 @@
-// !DIAGNOSTICS: -UNUSED_PARAMETER
-
-<!NOTHING_TO_INLINE!>inline<!> fun foo(noinline x: Int) {}
-
-<!NOTHING_TO_INLINE!>inline<!> fun bar(y: Int, crossinline x: String) {}
-
-fun gav(noinline x: (Int) -> Unit, crossinline y: (String) -> Int) {}
-
-inline fun correct(noinline x: (Int) -> Unit, crossinline y: (String) -> Int) {}
-
-<!NOTHING_TO_INLINE!>inline<!> fun incompatible(<!INCOMPATIBLE_MODIFIERS!>noinline<!> <!INCOMPATIBLE_MODIFIERS!>crossinline<!> x: () -> String) {}
-
-class FunctionSubtype : () -> Unit {
-    override fun invoke() {}
-}
-
-<!NOTHING_TO_INLINE!>inline<!> fun functionSubtype(
-    noinline f: FunctionSubtype,
-    crossinline g: FunctionSubtype
-) { }

compiler/testData/diagnostics/tests/modifiers/inlineParameters.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 // !DIAGNOSTICS: -UNUSED_PARAMETER
 
 <!NOTHING_TO_INLINE!>inline<!> fun foo(<!ILLEGAL_INLINE_PARAMETER_MODIFIER!>noinline<!> x: Int) {}

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/diagnostics/KtFirDataClassConverters.kt

@@ -3205,6 +3205,12 @@ internal val KT_DIAGNOSTIC_CONVERTER = KtDiagnosticConverterBuilder.buildConvert
             token,
         )
     }
+    add(FirErrors.ILLEGAL_INLINE_PARAMETER_MODIFIER) { firDiagnostic ->
+        IllegalInlineParameterModifierImpl(
+            firDiagnostic as FirPsiDiagnostic,
+            token,
+        )
+    }
     add(FirErrors.CANNOT_ALL_UNDER_IMPORT_FROM_SINGLETON) { firDiagnostic ->
         CannotAllUnderImportFromSingletonImpl(
             firDiagnostic.a,

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/diagnostics/KtFirDiagnostics.kt

@@ -2236,6 +2236,10 @@ sealed class KtFirDiagnostic<PSI : PsiElement> : KtDiagnosticWithPsi<PSI> {
         override val diagnosticClass get() = InlinePropertyWithBackingField::class
     }
 
+    abstract class IllegalInlineParameterModifier : KtFirDiagnostic<KtElement>() {
+        override val diagnosticClass get() = IllegalInlineParameterModifier::class
+    }
+
     abstract class CannotAllUnderImportFromSingleton : KtFirDiagnostic<KtImportDirective>() {
         override val diagnosticClass get() = CannotAllUnderImportFromSingleton::class
         abstract val objectName: Name

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/diagnostics/KtFirDiagnosticsImpl.kt

@@ -3611,6 +3611,13 @@ internal class InlinePropertyWithBackingFieldImpl(
     override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
 }
 
+internal class IllegalInlineParameterModifierImpl(
+    firDiagnostic: FirPsiDiagnostic,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.IllegalInlineParameterModifier(), KtAbstractFirDiagnostic<KtElement> {
+    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
+}
+
 internal class CannotAllUnderImportFromSingletonImpl(
     override val objectName: Name,
     firDiagnostic: FirPsiDiagnostic,