Extract private members of specialised generic classes on demand

Author: smowton

java/kotlin-extractor/src/main/kotlin/KotlinFileExtractor.kt

@@ -120,11 +120,7 @@ open class KotlinFileExtractor(
     }
 
     private fun shouldExtractDecl(declaration: IrDeclaration, extractPrivateMembers: Boolean) =
-        extractPrivateMembers ||
-        when(declaration) {
-            is IrDeclarationWithVisibility -> declaration.visibility.let { it != DescriptorVisibilities.PRIVATE && it != DescriptorVisibilities.PRIVATE_TO_THIS }
-            else -> true
-        }
+        extractPrivateMembers || !isPrivate(declaration)
 
     fun extractDeclaration(declaration: IrDeclaration, extractPrivateMembers: Boolean, extractFunctionBodies: Boolean) {
         with("declaration", declaration) {
@@ -357,23 +353,37 @@ open class KotlinFileExtractor(
         }
     }
 
+    private fun makeTypeParamSubstitution(c: IrClass, argsIncludingOuterClasses: List<IrTypeArgument>?) =
+        when (argsIncludingOuterClasses) {
+            null -> { x: IrType, _: TypeContext, _: IrPluginContext -> x.toRawType() }
+            else -> makeGenericSubstitutionFunction(c, argsIncludingOuterClasses)
+        }
+
+    fun extractDeclarationPrototype(d: IrDeclaration, parentId: Label<out DbReftype>, argsIncludingOuterClasses: List<IrTypeArgument>?, typeParamSubstitutionQ: TypeSubstitution? = null) {
+        val typeParamSubstitution = typeParamSubstitutionQ ?:
+            when(val parent = d.parent) {
+                is IrClass -> makeTypeParamSubstitution(parent, argsIncludingOuterClasses)
+                else -> {
+                    logger.warnElement("Unable to extract prototype of local declaration", d)
+                    return
+                }
+            }
+        when (d) {
+            is IrFunction -> extractFunction(d, parentId, extractBody = false, extractMethodAndParameterTypeAccesses = false, typeParamSubstitution, argsIncludingOuterClasses)
+            is IrProperty -> extractProperty(d, parentId, extractBackingField = false, extractFunctionBodies = false, extractPrivateMembers = false, typeParamSubstitution, argsIncludingOuterClasses)
+            else -> {}
+        }
+    }
+
     // `argsIncludingOuterClasses` can be null to describe a raw generic type.
     // For non-generic types it will be zero-length list.
     private fun extractNonPrivateMemberPrototypes(c: IrClass, argsIncludingOuterClasses: List<IrTypeArgument>?, id: Label<out DbClassorinterface>) {
         with("member prototypes", c) {
-            val typeParamSubstitution =
-                when (argsIncludingOuterClasses) {
-                    null -> { x: IrType, _: TypeContext, _: IrPluginContext -> x.toRawType() }
-                    else -> makeGenericSubstitutionFunction(c, argsIncludingOuterClasses)
-                }
+            val typeParamSubstitution = makeTypeParamSubstitution(c, argsIncludingOuterClasses)
 
             c.declarations.map {
                 if (shouldExtractDecl(it, false)) {
-                    when(it) {
-                        is IrFunction -> extractFunction(it, id, extractBody = false, extractMethodAndParameterTypeAccesses = false, typeParamSubstitution, argsIncludingOuterClasses)
-                        is IrProperty -> extractProperty(it, id, extractBackingField = false, extractFunctionBodies = false, extractPrivateMembers = false, typeParamSubstitution, argsIncludingOuterClasses)
-                        else -> {}
-                    }
+                    extractDeclarationPrototype(it, id, argsIncludingOuterClasses, typeParamSubstitution)
                 }
             }
         }

java/kotlin-extractor/src/main/kotlin/KotlinUsesExtractor.kt

@@ -1319,6 +1319,12 @@ open class KotlinUsesExtractor(
                 }
             } ?: f
 
+    fun isPrivate(d: IrDeclaration) =
+        when(d) {
+            is IrDeclarationWithVisibility -> d.visibility.let { it == DescriptorVisibilities.PRIVATE || it == DescriptorVisibilities.PRIVATE_TO_THIS }
+            else -> false
+        }
+
     fun <T: DbCallable> useFunction(f: IrFunction, classTypeArgsIncludingOuterClasses: List<IrTypeArgument>? = null, noReplace: Boolean = false): Label<out T> {
         return useFunction(f, null, classTypeArgsIncludingOuterClasses, noReplace)
     }
@@ -1330,10 +1336,22 @@ open class KotlinUsesExtractor(
         }
         val javaFun = kotlinFunctionToJavaEquivalent(f, noReplace)
         val label = getFunctionLabel(javaFun, parentId, classTypeArgsIncludingOuterClasses)
-        val id: Label<T> = tw.getLabelFor(label)
+        var labelSeenBefore = true
+        val id: Label<T> = tw.getLabelFor(label) {
+            labelSeenBefore = false
+        }
         if (isExternalDeclaration(javaFun)) {
             extractFunctionLaterIfExternalFileMember(javaFun)
             extractExternalEnclosingClassLater(javaFun)
+        } else if (!labelSeenBefore && classTypeArgsIncludingOuterClasses?.size != 0 && isPrivate(f)) {
+            // Private function call against a raw or instantiated generic class -- extract the prototype here, since the on-demand route via
+            // the class label only extracts the public interface. Note guarding this by `labelSeenBefore` is vital because `extractDeclarationPrototype`
+            // will call this function.
+            if (this is KotlinFileExtractor) {
+                useDeclarationParent(f.parent, false, classTypeArgsIncludingOuterClasses, inReceiverContext = true)?.let {
+                    this.extractDeclarationPrototype(f, it.cast(), classTypeArgsIncludingOuterClasses)
+                }
+            }
         }
         return id
     }
@@ -1687,7 +1705,18 @@ open class KotlinUsesExtractor(
     }
 
     fun useProperty(p: IrProperty, parentId: Label<out DbElement>, classTypeArgsIncludingOuterClasses: List<IrTypeArgument>?): Label<out DbKt_property> =
-        tw.getLabelFor<DbKt_property>(getPropertyLabel(p, parentId, classTypeArgsIncludingOuterClasses)).also { extractPropertyLaterIfExternalFileMember(p) }
+        tw.getLabelFor<DbKt_property>(getPropertyLabel(p, parentId, classTypeArgsIncludingOuterClasses)).also {
+            extractPropertyLaterIfExternalFileMember(p)
+            if (classTypeArgsIncludingOuterClasses?.size != 0 && isPrivate(p)) {
+                // Raw or constructed private property usage -- extract the prototype here, since the on-demand route via
+                // the class label only extracts the public interface.
+                if (this is KotlinFileExtractor) {
+                    useDeclarationParent(p.parent, false, classTypeArgsIncludingOuterClasses, inReceiverContext = true)?.let {
+                        this.extractDeclarationPrototype(p, it.cast(), classTypeArgsIncludingOuterClasses)
+                    }
+                }
+            }
+        }
 
     fun getEnumEntryLabel(ee: IrEnumEntry): String {
         val parentId = useDeclarationParent(ee.parent, false)