[KLIB tool] "dump-metadata-signatures" command: use stable sorted order

Print the signatures computed by the metadata always in stable sorted
order.

^KT-62340

kotlin-native/klib/src/main/kotlin/org/jetbrains/kotlin/cli/klib/SignaturePrinter.kt

@@ -2,23 +2,24 @@ package org.jetbrains.kotlin.cli.klib
 
 import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.descriptors.impl.DeclarationDescriptorVisitorEmptyBodies
-import org.jetbrains.kotlin.utils.Printer
+import org.jetbrains.kotlin.utils.addIfNotNull
 
 internal class SignaturePrinter(
-        out: Appendable,
+        private val output: Appendable,
         private val signatureRenderer: KlibSignatureRenderer
 ) {
-    private val printer = Printer(out)
-
     fun print(module: ModuleDescriptor) {
-        module.accept(PrinterVisitor(), Unit)
+        val collector = SignatureCollector()
+        module.accept(collector, Unit)
+
+        for (signature in collector.signatures.sorted()) {
+            output.appendLine(signature)
+        }
     }
 
-    private fun Printer.printlnIfNotNull(line: String?) {
+    private inner class SignatureCollector : DeclarationDescriptorVisitorEmptyBodies<Unit, Unit>() {
-        if (line != null) println(line)
+        val signatures: MutableSet<String> = hashSetOf()
-    }
 
-    private inner class PrinterVisitor : DeclarationDescriptorVisitorEmptyBodies<Unit, Unit>() {
         override fun visitModuleDeclaration(descriptor: ModuleDescriptor, data: Unit) {
             descriptor.getPackageFragments().forEach { it.accept(this, data) }
         }
@@ -28,27 +29,34 @@ internal class SignaturePrinter(
         }
 
         override fun visitClassDescriptor(descriptor: ClassDescriptor, data: Unit) {
-            printer.printlnIfNotNull(signatureRenderer.render(descriptor))
+            extractSignatureFromDeclaration(descriptor) {
-            descriptor.constructors.forEach { it.accept(this, data) }
+                descriptor.constructors.forEach { it.accept(this, data) }
-            descriptor.unsubstitutedMemberScope.getContributedDescriptors().forEach { it.accept(this, data) }
+                descriptor.unsubstitutedMemberScope.getContributedDescriptors().forEach { it.accept(this, data) }
+            }
         }
 
         override fun visitFunctionDescriptor(descriptor: FunctionDescriptor, data: Unit) {
-            printer.printlnIfNotNull(signatureRenderer.render(descriptor))
+            extractSignatureFromDeclaration(descriptor)
         }
 
         override fun visitPropertyDescriptor(descriptor: PropertyDescriptor, data: Unit) {
-            printer.printlnIfNotNull(signatureRenderer.render(descriptor))
+            extractSignatureFromDeclaration(descriptor) {
-            descriptor.getter?.let { printer.printlnIfNotNull(signatureRenderer.render(it)) }
+                descriptor.getter?.let(::extractSignatureFromDeclaration)
-            descriptor.setter?.let { printer.printlnIfNotNull(signatureRenderer.render(it)) }
+                descriptor.setter?.let(::extractSignatureFromDeclaration)
+            }
         }
 
         override fun visitConstructorDescriptor(descriptor: ConstructorDescriptor, data: Unit) {
-            printer.printlnIfNotNull(signatureRenderer.render(descriptor))
+            extractSignatureFromDeclaration(descriptor)
         }
 
         override fun visitTypeAliasDescriptor(descriptor: TypeAliasDescriptor, data: Unit) {
-            printer.printlnIfNotNull(signatureRenderer.render(descriptor))
+            extractSignatureFromDeclaration(descriptor)
+        }
+
+        private inline fun extractSignatureFromDeclaration(descriptor: DeclarationDescriptorWithVisibility, continuation: () -> Unit = {}) {
+            signatures.addIfNotNull(signatureRenderer.render(descriptor))
+            continuation()
         }
     }
 }