FIR IDE: add APIs about FunctionClassKind

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

@@ -12,10 +12,12 @@ import org.jetbrains.kotlin.analysis.api.types.KtNonErrorClassType
 import org.jetbrains.kotlin.analysis.api.types.KtType
 import org.jetbrains.kotlin.analysis.api.types.KtTypeNullability
 import org.jetbrains.kotlin.builtins.StandardNames
+import org.jetbrains.kotlin.builtins.functions.FunctionClassKind
 import org.jetbrains.kotlin.name.ClassId
 
 public abstract class KtTypeInfoProvider : KtAnalysisSessionComponent() {
     public abstract fun isFunctionalInterfaceType(type: KtType): Boolean
+    public abstract fun getFunctionClassKind(type: KtType): FunctionClassKind?
     public abstract fun canBeNull(type: KtType): Boolean
 }
 
@@ -26,6 +28,24 @@ public interface KtTypeInfoProviderMixIn : KtAnalysisSessionMixIn {
     public val KtType.isFunctionalInterfaceType: Boolean
         get() = analysisSession.typeInfoProvider.isFunctionalInterfaceType(this)
 
+    /**
+     * Returns [FunctionClassKind] of the given [KtType]
+     */
+    public val KtType.functionClassKind: FunctionClassKind?
+        get() = analysisSession.typeInfoProvider.getFunctionClassKind(this)
+
+    public val KtType.isFunctionType: Boolean
+        get() = functionClassKind == FunctionClassKind.Function
+
+    public val KtType.isKFunctionType: Boolean
+        get() = functionClassKind == FunctionClassKind.KFunction
+
+    public val KtType.isSuspendFunctionType: Boolean
+        get() = functionClassKind == FunctionClassKind.SuspendFunction
+
+    public val KtType.isKSuspendFunctionType: Boolean
+        get() = functionClassKind == FunctionClassKind.KSuspendFunction
+
     /**
      * Returns true if a public value of this type can potentially be null. This means this type is not a subtype of [Any]. However, it does not
      * mean one can assign `null` to a variable of this type because it may be unknown if this type can accept `null`. For example, a public value

analysis/analysis-api/testData/components/functionClassKind/function.kt

@@ -0,0 +1,7 @@
+fun <T, R> foo(p: T, mapper : (T) -> R): R {
+    mapper(p)
+}
+
+fun bar() {
+    foo(1, x<caret>y)
+}

analysis/analysis-api/testData/components/functionClassKind/function.txt

@@ -0,0 +1,3 @@
+expression: xy
+expected type: (T) -> R
+functionClassKind: Function

analysis/analysis-api/testData/components/functionClassKind/kFunction.kt

@@ -0,0 +1,11 @@
+// WITH_REFLECT
+
+import kotlin.reflect.KFunction1
+
+fun <T, R> foo(p: T, mapper : (T) -> R): R {
+    mapper(p)
+}
+
+fun bar() {
+    foo(1, x<caret>y as KFunction1<Int, String>)
+}

analysis/analysis-api/testData/components/functionClassKind/kFunction.txt

@@ -0,0 +1,3 @@
+expression: xy
+expected type: (kotlin.Int) -> kotlin.String
+functionClassKind: KFunction

analysis/analysis-api/testData/components/functionClassKind/kSuspendFunction.kt

@@ -0,0 +1,11 @@
+// WITH_REFLECT
+
+import kotlin.reflect.KSuspendFunction0
+
+fun foo(pause : suspend () -> Unit) {
+    pause()
+}
+
+fun bar() {
+    foo(x<caret>y as KSuspendFunction0<Unit>)
+}

analysis/analysis-api/testData/components/functionClassKind/kSuspendFunction.txt

@@ -0,0 +1,3 @@
+expression: xy
+expected type: suspend () -> kotlin.Unit
+functionClassKind: KSuspendFunction

analysis/analysis-api/testData/components/functionClassKind/suspendFunction.kt

@@ -0,0 +1,7 @@
+fun foo(pause : suspend () -> Unit) {
+    pause()
+}
+
+fun bar() {
+    foo(x<caret>y)
+}

analysis/analysis-api/testData/components/functionClassKind/suspendFunction.txt

@@ -0,0 +1,3 @@
+expression: xy
+expected type: suspend () -> kotlin.Unit
+functionClassKind: SuspendFunction