[Analysis API] Add API for expect/actual declaration detection

analysis/analysis-api-fe10/src/org/jetbrains/kotlin/analysis/api/descriptors/components/KtFe10MultiplatformInfoProvider.kt

@@ -16,6 +16,7 @@ import org.jetbrains.kotlin.analysis.utils.errors.checkWithAttachmentBuilder
 import org.jetbrains.kotlin.descriptors.MemberDescriptor
 import org.jetbrains.kotlin.psi.KtDeclaration
 import org.jetbrains.kotlin.psi.psiUtil.hasActualModifier
+import org.jetbrains.kotlin.psi.psiUtil.hasExpectModifier
 import org.jetbrains.kotlin.resolve.multiplatform.ExpectActualCompatibility
 import org.jetbrains.kotlin.resolve.multiplatform.ExpectedActualResolver
 
@@ -23,7 +24,7 @@ internal class KtFe10MultiplatformInfoProvider(
     override val analysisSession: KtFe10AnalysisSession
 ) : KtMultiplatformInfoProvider(), Fe10KtAnalysisSessionComponent {
     override fun getExpectForActual(actual: KtDeclarationSymbol): KtDeclarationSymbol? {
-        if (actual.psiSafe<KtDeclaration>()?.hasActualModifier() != true) return null
+        if (!isActual(actual)) return null
         val memberDescriptor = (getSymbolDescriptor(actual) as? MemberDescriptor)?.takeIf { it.isActual } ?: return null
 
         val expectedCompatibilityMap =
@@ -41,4 +42,8 @@ internal class KtFe10MultiplatformInfoProvider(
         }
         return expectsForActual.singleOrNull()?.toKtSymbol(analysisContext) as? KtDeclarationSymbol
     }
+
+    override fun isActual(symbol: KtDeclarationSymbol): Boolean = symbol.psiSafe<KtDeclaration>()?.hasActualModifier() == true
+
+    override fun isExpect(symbol: KtDeclarationSymbol): Boolean = symbol.psiSafe<KtDeclaration>()?.hasExpectModifier() == true
 }

analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/components/KtFirMultiplatformInfoProvider.kt

@@ -12,6 +12,7 @@ import org.jetbrains.kotlin.analysis.api.lifetime.KtLifetimeToken
 import org.jetbrains.kotlin.analysis.api.symbols.KtDeclarationSymbol
 import org.jetbrains.kotlin.analysis.low.level.api.fir.util.withFirSymbolEntry
 import org.jetbrains.kotlin.analysis.utils.errors.checkWithAttachmentBuilder
+import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
 import org.jetbrains.kotlin.fir.declarations.expectForActual
 import org.jetbrains.kotlin.fir.symbols.impl.FirCallableSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirClassSymbol
@@ -25,13 +26,7 @@ internal class KtFirMultiplatformInfoProvider(
     override fun getExpectForActual(actual: KtDeclarationSymbol): KtDeclarationSymbol? {
         require(actual is KtFirSymbol<*>)
         val firSymbol = actual.firSymbol
-        val status = when (firSymbol) {
+        if (!isActual(actual)) return null
-            is FirCallableSymbol -> firSymbol.rawStatus
-            is FirClassSymbol -> firSymbol.rawStatus
-            is FirTypeAliasSymbol -> firSymbol.rawStatus
-            else -> null
-        }
-        if (status?.isActual != true) return null
 
         val expectsForActual = firSymbol.expectForActual?.get(ExpectActualCompatibility.Compatible) ?: return null
         checkWithAttachmentBuilder(expectsForActual.size <= 1, message = { "expected as maximum one `expect` for the actual" }) {
@@ -43,4 +38,19 @@ internal class KtFirMultiplatformInfoProvider(
         }
         return expectsForActual.singleOrNull()?.let { analysisSession.firSymbolBuilder.buildSymbol(it) as? KtDeclarationSymbol }
     }
+
+    override fun isActual(symbol: KtDeclarationSymbol): Boolean = getStatus(symbol)?.isActual == true
+
+    override fun isExpect(symbol: KtDeclarationSymbol): Boolean = getStatus(symbol)?.isExpect == true
+
+    private fun getStatus(symbol: KtDeclarationSymbol): FirDeclarationStatus? {
+        require(symbol is KtFirSymbol<*>)
+        val firSymbol = symbol.firSymbol
+        return when (firSymbol) {
+            is FirCallableSymbol -> firSymbol.rawStatus
+            is FirClassSymbol -> firSymbol.rawStatus
+            is FirTypeAliasSymbol -> firSymbol.rawStatus
+            else -> null
+        }
+    }
 }

analysis/analysis-api/src/org/jetbrains/kotlin/analysis/api/components/KtMultiplatformInfoProvider.kt

@@ -10,6 +10,8 @@ import org.jetbrains.kotlin.analysis.api.symbols.KtDeclarationSymbol
 
 public abstract class KtMultiplatformInfoProvider : KtAnalysisSessionComponent() {
     public abstract fun getExpectForActual(actual: KtDeclarationSymbol): KtDeclarationSymbol?
+    public abstract fun isActual(symbol: KtDeclarationSymbol): Boolean
+    public abstract fun isExpect(symbol: KtDeclarationSymbol): Boolean
 }
 
 public interface KtMultiplatformInfoProviderMixin : KtAnalysisSessionMixIn {
@@ -20,4 +22,7 @@ public interface KtMultiplatformInfoProviderMixin : KtAnalysisSessionMixIn {
     public fun KtDeclarationSymbol.getExpectForActual(): KtDeclarationSymbol? =
         withValidityAssertion { analysisSession.multiplatformInfoProvider.getExpectForActual(this) }
 
+    public fun KtDeclarationSymbol.isActual(): Boolean = withValidityAssertion { analysisSession.multiplatformInfoProvider.isActual(this) }
+
+    public fun KtDeclarationSymbol.isExpect(): Boolean = withValidityAssertion { analysisSession.multiplatformInfoProvider.isExpect(this) }
 }