New J2K: do not find import usages in AST building phase

It is a rather heavy operation and it increases conversion time
Related to #KT-31848

nj2k/nj2k-services/src/org/jetbrains/kotlin/nj2k/postProcessing/J2kPostProcessor.kt

@@ -279,5 +279,6 @@ private val processings: List<GeneralPostProcessing> = listOf(
         RemoveForExpressionLoopParameterTypeProcessing()
     ),
     formatCodeProcessing,
-    optimizeImportsProcessing
+    optimizeImportsProcessing,
+    shortenReferencesProcessing
 )

nj2k/src/org/jetbrains/kotlin/nj2k/JavaToJKTreeBuilder.kt

@@ -30,10 +30,10 @@ import com.intellij.psi.impl.source.tree.java.PsiLiteralExpressionImpl
 import com.intellij.psi.impl.source.tree.java.PsiNewExpressionImpl
 import com.intellij.psi.infos.MethodCandidateInfo
 import com.intellij.psi.javadoc.PsiDocComment
-import com.intellij.psi.search.searches.ReferencesSearch
 import com.intellij.psi.tree.IElementType
-import com.intellij.psi.util.PsiTreeUtil
+import org.jetbrains.kotlin.asJava.classes.KtLightClass
 import org.jetbrains.kotlin.asJava.classes.KtLightClassForFacade
+import org.jetbrains.kotlin.asJava.elements.KtLightElement
 import org.jetbrains.kotlin.asJava.elements.KtLightField
 import org.jetbrains.kotlin.asJava.elements.KtLightMethod
 import org.jetbrains.kotlin.idea.caches.lightClasses.KtLightClassForDecompiledDeclaration
@@ -68,32 +68,12 @@ class JavaToJKTreeBuilder constructor(
     private fun PsiJavaFile.toJK(): JKFile =
         JKFileImpl(
             packageStatement?.toJK() ?: JKPackageDeclarationImpl(JKNameIdentifierImpl("")),
-            importList.toJK(filterOutUsedImports = true),
+            importList.toJK(),
             with(declarationMapper) { classes.map { it.toJK() } }
         )
 
-    private fun PsiImportList?.toJK(filterOutUsedImports: Boolean): JKImportList =
-        JKImportListImpl(
-            this?.allImportStatements?.let { imports ->
-                if (filterOutUsedImports) {
-                    imports.filter { import ->
-                        when {
-                            import.isSingleUnusedImport() -> true
-                            import.isOnDemand -> true
-                            else -> false
-                        }
-                    }
-                } else imports.toList()
-            }?.mapNotNull { it.toJK() }.orEmpty()
-        )
-
-
-    private fun PsiImportStatementBase.isSingleUnusedImport(): Boolean {
-        if (isOnDemand) return false
-        val target = resolve() ?: return true
-        val usages = ReferencesSearch.search(target).toList()
-        return usages.size == 1 && PsiTreeUtil.isAncestor(this, usages.iterator().next().element, true)
-    }
+    private fun PsiImportList?.toJK(): JKImportList =
+        JKImportListImpl(this?.allImportStatements?.mapNotNull { it.toJK() }.orEmpty())
 
     private fun PsiPackageStatement.toJK(): JKPackageDeclaration =
         JKPackageDeclarationImpl(JKNameIdentifierImpl(packageName))
@@ -106,8 +86,12 @@ class JavaToJKTreeBuilder constructor(
         val target = resolve()
         val rawName = (importReference?.canonicalText ?: return null) + if (isOnDemand) ".*" else ""
         val name =
-            if (target is KtLightClassForFacade) target.fqName.parent().asString() + ".*"
-            else rawName
+            target.safeAs<KtLightElement<*, *>>()?.kotlinOrigin?.getKotlinFqName()?.asString()
+                ?: target.safeAs<KtLightClass>()?.containingFile?.safeAs<KtFile>()?.packageFqName?.asString()?.let { "$it.*" }
+                ?: target.safeAs<KtLightClassForFacade>()?.fqName?.parent()?.asString()?.let { "$it.*" }
+                ?: target.safeAs<KtLightClassForDecompiledDeclaration>()?.fqName?.parent()?.asString()?.let { "$it.*" }
+                ?: rawName
+
         return JKImportStatementImpl(JKNameIdentifierImpl(name))
             .also {
                 it.assignNonCodeElements(this)
@@ -929,7 +913,7 @@ class JavaToJKTreeBuilder constructor(
             is PsiField -> with(declarationMapper) { psi.toJK() }
             is PsiMethod -> with(declarationMapper) { psi.toJK() }
             is PsiAnnotation -> with(declarationMapper) { psi.toJK() }
-            is PsiImportList -> psi.toJK(filterOutUsedImports = false)
+            is PsiImportList -> psi.toJK()
             is PsiImportStatement -> psi.toJK()
             is PsiJavaCodeReferenceElement ->
                 if (psi.parent is PsiReferenceList) {

nj2k/testData/newJ2k/assignmentExpression/nullability-settings.kt

@@ -1,6 +1,8 @@
 // !forceNotNullTypes: false
 // !specifyLocalVariableTypeByDefault: true
 
+import java.util.HashSet
+
 internal class Foo {
     fun foo(o: HashSet<*>) {
         val o2: HashSet<*> = o

nj2k/testData/newJ2k/assignmentExpression/nullability.kt

@@ -1,3 +1,5 @@
+import java.util.HashSet
+
 internal class Foo {
     fun foo(o: HashSet<*>) {
         var foo = 0

nj2k/testData/newJ2k/class/kt-639.kt

@@ -2,6 +2,8 @@
 // ERROR: Type inference failed: Not enough information to infer parameter K in constructor HashMap<K : Any!, V : Any!>(initialCapacity: Int) Please specify it explicitly.
 package demo
 
+import java.util.HashMap
+
 internal class Test {
     constructor() {}
     constructor(s: String?) {}

nj2k/testData/newJ2k/constructors/nestedClassNameInParameterDefaults2.kt

@@ -1,3 +1,5 @@
+import A.Nested
+
 internal class A @JvmOverloads constructor(nested: Nested = Nested(Nested.FIELD)) {
     internal class Nested(p: Int) {
         companion object {
@@ -7,5 +9,5 @@ internal class A @JvmOverloads constructor(nested: Nested = Nested(Nested.FIELD)
 }
 
 internal class B {
-    var nested: A.Nested? = null
+    var nested: Nested? = null
 }

nj2k/testData/newJ2k/constructors/nestedClassNameInParameterDefaults3.kt

@@ -1,5 +1,7 @@
 package pack
 
+import pack.A.Nested
+
 internal class A @JvmOverloads constructor(nested: Nested = Nested(Nested.FIELD)) {
     internal class Nested(p: Int) {
         companion object {
@@ -9,5 +11,5 @@ internal class A @JvmOverloads constructor(nested: Nested = Nested(Nested.FIELD)
 }
 
 internal class B {
-    var nested: A.Nested? = null
+    var nested: Nested? = null
 }

nj2k/testData/newJ2k/detectProperties/PropertyType.kt

@@ -1,3 +1,5 @@
+import java.util.ArrayList
+
 internal class A {
     private val list1: ArrayList<String> = ArrayList()
     private val list2: MutableList<String> = ArrayList()

nj2k/testData/newJ2k/for/forThroughListIndices.kt

@@ -1,3 +1,5 @@
+import java.util.ArrayList
+
 internal class C {
     fun foo1(list: MutableList<String>) {
         for (i in list.indices) {

nj2k/testData/newJ2k/for/overMapEntries.kt

@@ -1,3 +1,5 @@
+import java.util.HashMap
+
 internal object Test {
     @JvmStatic
     fun main(args: Array<String>) {

nj2k/testData/newJ2k/function/java8MRKFunctionExpectedType.kt

@@ -77,7 +77,7 @@ internal class Java8Class {
     }
 
     fun testGenericFunctions() {
-        val emptyList: Function0<kotlin.collections.List<String>> = { emptyList() }
+        val emptyList: Function0<List<String>> = { emptyList() }
         val list = emptyList.invoke()
         list[0]
     }

nj2k/testData/newJ2k/function/java8MRSamConstructor.kt

@@ -122,10 +122,10 @@ internal class Java8Class {
     }
 
     fun testGenericFunctions() {
-        val emptyList: JFunction1<kotlin.collections.List<String>> = JFunction1 { emptyList() }
+        val emptyList: JFunction1<List<String>> = JFunction1 { emptyList() }
         emptyList.foo()
-        MethodReferenceHelperClass.staticFun1(JFunction1<kotlin.collections.List<String>> { emptyList() })
-        h.memberFun1(JFunction1<kotlin.collections.List<String>> { emptyList() })
+        MethodReferenceHelperClass.staticFun1(JFunction1<List<String>> { emptyList() })
+        h.memberFun1(JFunction1<List<String>> { emptyList() })
     }
 
     fun memberFun(): Int {

nj2k/testData/newJ2k/issues/kt-1048.kt

@@ -1,6 +1,8 @@
 // ERROR: The integer literal does not conform to the expected type CapturedType(*)
 // ERROR: The integer literal does not conform to the expected type CapturedType(*)
 // ERROR: Type argument is not within its bounds: should be subtype of 'String?'
+import java.util.HashMap
+
 internal class G<T : String?>(t: T?)
 class Java {
     internal fun test() {

nj2k/testData/newJ2k/issues/kt-6790.kt

@@ -1,5 +1,3 @@
-import kotlin.collections.Map.Entry
-
 class A {
-    internal fun foo(o: Entry<Any?, Any?>?) {}
+    internal fun foo(o: Map.Entry<Any?, Any?>?) {}
 }

nj2k/testData/newJ2k/kotlinApiAccess/StaticImportFromCompanionObject.kt

@@ -1,7 +1,7 @@
-import kotlinApi.KotlinClass
+import kotlinApi.KotlinClass.Companion.CONST
 
 class C {
     internal fun bar() {
-        println(KotlinClass.CONST)
+        println(CONST)
     }
 }

nj2k/testData/newJ2k/mutableCollections/Iterator2.kt

@@ -1,3 +1,5 @@
+import java.util.ArrayList
+
 class TestMutableCollection {
     val list: MutableList<String> = ArrayList()
 

nj2k/testData/newJ2k/newClassExpression/genericClassInvocation.kt

@@ -1,3 +1,5 @@
+import java.util.ArrayList
+
 internal class User {
     fun main() {
         val list: List<String> = ArrayList()

nj2k/testData/newJ2k/newClassExpression/newListAndNewMember.kt

@@ -1,5 +1,7 @@
 package org.test
 
+import java.util.ArrayList
+
 internal class Member
 internal class User {
     fun main() {

nj2k/testData/newJ2k/nullability/nullableField.kt

@@ -1,5 +1,7 @@
 package test
 
+import java.util.ArrayList
+
 class Test {
     private var myProp: String? = null
     private var myIntProp: Int? = null

nj2k/testData/newJ2k/postProcessing/GetOperator.kt

@@ -1,5 +1,6 @@
 import javaApi.JavaClass
 import kotlinApi.KotlinClass
+import java.util.HashMap
 
 internal class X {
     operator fun get(index: Int): Int {

nj2k/testData/newJ2k/postProcessing/java8MapForEachWithFullJdk.kt

@@ -1,3 +1,5 @@
+import java.util.HashMap
+
 internal class Test {
     fun test(map: HashMap<String, String>) {
         map.forEach { (key: String, value: String) -> foo(key, value) }

nj2k/testData/newJ2k/projections/projections.kt

@@ -1,3 +1,5 @@
+import java.util.ArrayList
+
 internal class C<T> {
     fun foo1(src: Collection<T>) {
         val t = src.iterator().next()

nj2k/testData/newJ2k/rawGenerics/kt-540-map.kt

@@ -1,5 +1,7 @@
 package demo
 
+import java.util.HashMap
+
 internal class Test {
     fun main() {
         val commonMap: HashMap<String, Int> = HashMap()

nj2k/testData/newJ2k/rawGenerics/kt-540.kt

@@ -1,5 +1,7 @@
 package demo
 
+import java.util.ArrayList
+
 internal class Test {
     fun main() {
         val common: List<String> = ArrayList()

nj2k/testData/newJ2k/toKotlinClasses/LibraryFunctions.kt

@@ -1,5 +1,7 @@
 package demo
 
+import java.util.ArrayList
+
 class TestJava {
     fun f(result: Function1<String, Unit?>) {
         result.invoke("a")

nj2k/testData/newJ2k/typeParameters/needTypeArgs.kt

@@ -1,3 +1,5 @@
+import java.util.HashMap
+
 internal class A {
     fun foo() {
         val map1: Map<String, Int> = getMap1()