FIR: Change diagnostic for ConeHiddenCandidate to UNRESOLVED_REFERENCE.

The KDoc for @Deprecated states that DeprecationLevel.HIDDEN usages
should look like unresolved references.

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

@@ -22,29 +22,42 @@ import org.jetbrains.kotlin.fir.resolve.inference.model.ConeExpectedTypeConstrai
 import org.jetbrains.kotlin.fir.resolve.inference.model.ConeLambdaArgumentConstraintPosition
 import org.jetbrains.kotlin.fir.resolve.isTypeMismatchDueToNullability
 import org.jetbrains.kotlin.fir.symbols.impl.FirBackingFieldSymbol
+import org.jetbrains.kotlin.fir.symbols.impl.FirCallableSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirNamedFunctionSymbol
 import org.jetbrains.kotlin.fir.typeContext
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.lexer.KtTokens
+import org.jetbrains.kotlin.name.SpecialNames
 import org.jetbrains.kotlin.resolve.calls.inference.model.*
 import org.jetbrains.kotlin.resolve.calls.tower.CandidateApplicability
 import org.jetbrains.kotlin.resolve.calls.tower.isSuccess
 import org.jetbrains.kotlin.utils.addIfNotNull
 import org.jetbrains.kotlin.utils.addToStdlib.firstIsInstance
 import org.jetbrains.kotlin.utils.addToStdlib.runIf
+import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 
 private fun ConeDiagnostic.toFirDiagnostic(
     source: FirSourceElement,
     qualifiedAccessSource: FirSourceElement?
 ): FirDiagnostic? = when (this) {
-    is ConeUnresolvedReferenceError -> FirErrors.UNRESOLVED_REFERENCE.createOn(source, this.name?.asString() ?: "<No name>")
+    is ConeUnresolvedReferenceError -> FirErrors.UNRESOLVED_REFERENCE.createOn(
+        source,
+        (this.name ?: SpecialNames.NO_NAME_PROVIDED).asString()
+    )
     is ConeUnresolvedSymbolError -> FirErrors.UNRESOLVED_REFERENCE.createOn(source, this.classId.asString())
     is ConeUnresolvedNameError -> FirErrors.UNRESOLVED_REFERENCE.createOn(source, this.name.asString())
     is ConeUnresolvedQualifierError -> FirErrors.UNRESOLVED_REFERENCE.createOn(source, this.qualifier)
     is ConeFunctionCallExpectedError -> FirErrors.FUNCTION_CALL_EXPECTED.createOn(source, this.name.asString(), this.hasValueParameters)
     is ConeFunctionExpectedError -> FirErrors.FUNCTION_EXPECTED.createOn(source, this.expression, this.type)
     is ConeResolutionToClassifierError -> FirErrors.RESOLUTION_TO_CLASSIFIER.createOn(source, this.candidateSymbol)
-    is ConeHiddenCandidateError -> FirErrors.INVISIBLE_REFERENCE.createOn(source, this.candidateSymbol)
+    is ConeHiddenCandidateError -> {
+        // Usages of callables with @Deprecated(DeprecationLevel.HIDDEN) should look like unresolved references.
+        // See: https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-deprecated/
+        FirErrors.UNRESOLVED_REFERENCE.createOn(
+            source,
+            (this.candidateSymbol.safeAs<FirCallableSymbol<*>>()?.name ?: SpecialNames.NO_NAME_PROVIDED).asString()
+        )
+    }
     is ConeVisibilityError -> FirErrors.INVISIBLE_REFERENCE.createOn(source, this.candidateSymbol)
     is ConeInapplicableWrongReceiver -> FirErrors.UNRESOLVED_REFERENCE_WRONG_RECEIVER.createOn(source, this.candidateSymbols)
     is ConeNoCompanionObject -> FirErrors.NO_COMPANION_OBJECT.createOn(source, this.candidateSymbol)

compiler/testData/diagnostics/tests/deprecated/deprecatedInheritance_after.fir.kt

@@ -115,7 +115,7 @@ fun use(
 ) {
     wd.<!DEPRECATION!>f<!>()
     ed.<!DEPRECATION_ERROR!>f<!>()
-    hd.<!INVISIBLE_REFERENCE!>f<!>()
+    hd.<!UNRESOLVED_REFERENCE!>f<!>()
 
     we.f()
     wh.f()

compiler/testData/diagnostics/tests/deprecated/deprecatedInheritance_before.fir.kt

@@ -115,7 +115,7 @@ fun use(
 ) {
     wd.<!DEPRECATION!>f<!>()
     ed.<!DEPRECATION_ERROR!>f<!>()
-    hd.<!INVISIBLE_REFERENCE!>f<!>()
+    hd.<!UNRESOLVED_REFERENCE!>f<!>()
 
     we.f()
     wh.f()

compiler/testData/diagnostics/tests/deprecated/deprecatedPropertyInheritance_after.fir.kt

@@ -107,8 +107,8 @@ fun use(
     setterDeprecated.p
     setterDeprecated.p <!DEPRECATION!>=<!> 1
 
-    hiddenDeprecated.<!INVISIBLE_REFERENCE!>p<!>
+    hiddenDeprecated.<!UNRESOLVED_REFERENCE!>p<!>
-    hiddenDeprecated.<!INVISIBLE_REFERENCE!>p<!> = 1
+    hiddenDeprecated.<!UNRESOLVED_REFERENCE!>p<!> = 1
 
     wd.p
     wd.p = 1
@@ -132,5 +132,5 @@ fun use(
     ned.p = 1
 
     diff.<!DEPRECATION_ERROR!>p<!>
-    diff.<!INVISIBLE_REFERENCE!>p<!> = 1
+    diff.<!UNRESOLVED_REFERENCE!>p<!> = 1
 }

compiler/testData/diagnostics/tests/deprecated/deprecatedPropertyInheritance_before.fir.kt

@@ -107,8 +107,8 @@ fun use(
     setterDeprecated.p
     setterDeprecated.p <!DEPRECATION!>=<!> 1
 
-    hiddenDeprecated.<!INVISIBLE_REFERENCE!>p<!>
+    hiddenDeprecated.<!UNRESOLVED_REFERENCE!>p<!>
-    hiddenDeprecated.<!INVISIBLE_REFERENCE!>p<!> = 1
+    hiddenDeprecated.<!UNRESOLVED_REFERENCE!>p<!> = 1
 
     wd.p
     wd.p = 1
@@ -132,5 +132,5 @@ fun use(
     ned.p = 1
 
     diff.<!DEPRECATION_ERROR!>p<!>
-    diff.<!INVISIBLE_REFERENCE!>p<!> = 1
+    diff.<!UNRESOLVED_REFERENCE!>p<!> = 1
 }

compiler/testData/diagnostics/tests/deprecated/deprecatedSinceKotlin/hidden.fir.kt

@@ -1,37 +0,0 @@
-// !API_VERSION: 1.4
-
-package kotlin
-
-@Deprecated("")
-@DeprecatedSinceKotlin(hiddenSince = "1.4")
-class ClassCur
-
-@Deprecated("")
-@DeprecatedSinceKotlin(hiddenSince = "1.4")
-fun funCur() {}
-
-@Deprecated("")
-@DeprecatedSinceKotlin(hiddenSince = "1.4")
-val valCur = Unit
-
-@Deprecated("")
-@DeprecatedSinceKotlin(hiddenSince = "1.5")
-class ClassNext
-
-@Deprecated("")
-@DeprecatedSinceKotlin(hiddenSince = "1.5")
-fun funNext() {}
-
-@Deprecated("")
-@DeprecatedSinceKotlin(hiddenSince = "1.5")
-val valNext = Unit
-
-fun usage() {
-    <!DEPRECATION_ERROR!>ClassCur<!>()
-    <!INVISIBLE_REFERENCE!>funCur<!>()
-    <!INVISIBLE_REFERENCE!>valCur<!>
-
-    ClassNext()
-    funNext()
-    valNext
-}

compiler/testData/diagnostics/tests/deprecated/deprecatedSinceKotlin/hidden.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 // !API_VERSION: 1.4
 
 package kotlin

compiler/testData/diagnostics/tests/deprecated/hiddenPropertyAccessors.fir.kt

@@ -27,14 +27,14 @@ var v6: String
     set(value) {}
 
 fun test() {
-    <!INVISIBLE_REFERENCE!>v1<!>
+    <!UNRESOLVED_REFERENCE!>v1<!>
-    <!INVISIBLE_REFERENCE!>v2<!>
+    <!UNRESOLVED_REFERENCE!>v2<!>
-    <!INVISIBLE_REFERENCE!>v3<!>
+    <!UNRESOLVED_REFERENCE!>v3<!>
     v3 = ""
     v4
-    <!INVISIBLE_REFERENCE!>v4<!> = ""
+    <!UNRESOLVED_REFERENCE!>v4<!> = ""
-    <!INVISIBLE_REFERENCE!>v5<!>
+    <!UNRESOLVED_REFERENCE!>v5<!>
-    <!INVISIBLE_REFERENCE!>v5<!> = ""
+    <!UNRESOLVED_REFERENCE!>v5<!> = ""
-    <!INVISIBLE_REFERENCE!>v6<!>
+    <!UNRESOLVED_REFERENCE!>v6<!>
-    <!INVISIBLE_REFERENCE!>v6<!> = ""
+    <!UNRESOLVED_REFERENCE!>v6<!> = ""
 }

compiler/testData/diagnostics/tests/operatorRem/resolveModIfRemIsHidden.fir.kt

@@ -9,7 +9,7 @@ object A {
 }
 
 fun test() {
-    takeString(<!ARGUMENT_TYPE_MISMATCH!>A <!INVISIBLE_REFERENCE!>%<!> 123<!>)
+    takeString(<!ARGUMENT_TYPE_MISMATCH!>A <!UNRESOLVED_REFERENCE!>%<!> 123<!>)
 }
 
-fun takeString(s: String) {}
+fun takeString(s: String) {}

compiler/testData/diagnostics/tests/resolve/HiddenDeclarations.fir.kt

@@ -38,23 +38,23 @@ open class A {
     val String.memberExtensionProperty: Int get() = 1
 
     fun foo() {
-        <!INVISIBLE_REFERENCE!>topLevelFun<!>()
+        <!UNRESOLVED_REFERENCE!>topLevelFun<!>()
-        <!INVISIBLE_REFERENCE!>topLevelFun<!>(1)
+        <!UNRESOLVED_REFERENCE!>topLevelFun<!>(1)
-        <!INVISIBLE_REFERENCE, INVISIBLE_REFERENCE!>topLevelProperty<!>++
+        <!UNRESOLVED_REFERENCE, UNRESOLVED_REFERENCE!>topLevelProperty<!>++
-        "".<!INVISIBLE_REFERENCE!>topLevelExtensionFun<!>()
+        "".<!UNRESOLVED_REFERENCE!>topLevelExtensionFun<!>()
-        1.<!INVISIBLE_REFERENCE!>topLevelExtensionFun<!>()
+        1.<!UNRESOLVED_REFERENCE!>topLevelExtensionFun<!>()
-        "".<!INVISIBLE_REFERENCE!>topLevelExtensionProperty<!>
+        "".<!UNRESOLVED_REFERENCE!>topLevelExtensionProperty<!>
-        1.<!INVISIBLE_REFERENCE!>topLevelExtensionProperty<!>
+        1.<!UNRESOLVED_REFERENCE!>topLevelExtensionProperty<!>
 
-        <!INVISIBLE_REFERENCE!>memberFun<!>()
+        <!UNRESOLVED_REFERENCE!>memberFun<!>()
-        <!INVISIBLE_REFERENCE!>memberFun<!>(1)
+        <!UNRESOLVED_REFERENCE!>memberFun<!>(1)
-        <!INVISIBLE_REFERENCE!>privateFun<!>()
+        <!UNRESOLVED_REFERENCE!>privateFun<!>()
-        <!INVISIBLE_REFERENCE!>privateFun<!>(1)
+        <!UNRESOLVED_REFERENCE!>privateFun<!>(1)
-        <!INVISIBLE_REFERENCE!>memberProperty<!>
+        <!UNRESOLVED_REFERENCE!>memberProperty<!>
-        "".<!INVISIBLE_REFERENCE!>memberExtensionFun<!>()
+        "".<!UNRESOLVED_REFERENCE!>memberExtensionFun<!>()
-        1.<!INVISIBLE_REFERENCE!>memberExtensionFun<!>()
+        1.<!UNRESOLVED_REFERENCE!>memberExtensionFun<!>()
-        "".<!INVISIBLE_REFERENCE!>memberExtensionProperty<!>
+        "".<!UNRESOLVED_REFERENCE!>memberExtensionProperty<!>
-        1.<!INVISIBLE_REFERENCE!>memberExtensionProperty<!>
+        1.<!UNRESOLVED_REFERENCE!>memberExtensionProperty<!>
 
         A(<!ARGUMENT_TYPE_MISMATCH!>""<!>)
     }
@@ -76,9 +76,9 @@ interface I {
 class B : A(<!ARGUMENT_TYPE_MISMATCH!>""<!>) {
     // still can override it
     override fun <!OVERRIDE_DEPRECATION!>memberFun<!>() {
-        super.<!INVISIBLE_REFERENCE!>memberFun<!>() // but cannot call super :)
+        super.<!UNRESOLVED_REFERENCE!>memberFun<!>() // but cannot call super :)
-        <!INVISIBLE_REFERENCE!>privateFun<!>()
+        <!UNRESOLVED_REFERENCE!>privateFun<!>()
-        <!INVISIBLE_REFERENCE!>privateFun<!>(1)
+        <!UNRESOLVED_REFERENCE!>privateFun<!>(1)
     }
 }