From b84084d54e1cfa7df250f9c85af6ad46d4d0019c Mon Sep 17 00:00:00 2001
From: Roman Artemev <roman.artemev@jetbrains.com>
Date: Wed, 9 Sep 2020 16:41:15 +0300
Subject: [PATCH] [IR] Support hidden parameters in IrMangler

 - make them be skipped in signature
---
 .../serialization/mangle/ir/IrMangleComputer.kt | 17 ++++++++++-------
 .../common/serialization/mangle/mangleUtils.kt  | 13 ++++++++++++-
 2 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/mangle/ir/IrMangleComputer.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/mangle/ir/IrMangleComputer.kt
index 94dfc3aed27..d6f505833c8 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/mangle/ir/IrMangleComputer.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/mangle/ir/IrMangleComputer.kt
@@ -5,9 +5,7 @@
 
 package org.jetbrains.kotlin.backend.common.serialization.mangle.ir
 
-import org.jetbrains.kotlin.backend.common.serialization.mangle.KotlinMangleComputer
-import org.jetbrains.kotlin.backend.common.serialization.mangle.MangleConstant
-import org.jetbrains.kotlin.backend.common.serialization.mangle.MangleMode
+import org.jetbrains.kotlin.backend.common.serialization.mangle.*
 import org.jetbrains.kotlin.backend.common.serialization.mangle.collectForMangler
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.*
@@ -106,14 +104,19 @@ abstract class IrMangleComputer(protected val builder: StringBuilder, private va
         }
 
         extensionReceiverParameter?.let {
-            builder.appendSignature(MangleConstant.EXTENSION_RECEIVER_PREFIX)
-            mangleValueParameter(builder, it)
+            if (!it.isHidden) {
+                builder.appendSignature(MangleConstant.EXTENSION_RECEIVER_PREFIX)
+                mangleValueParameter(builder, it)
+            }
         }
 
         valueParameters.collectForMangler(builder, MangleConstant.VALUE_PARAMETERS) {
-            appendSignature(specialValueParamPrefix(it))
-            mangleValueParameter(this, it)
+            if (!it.isHidden) {
+                appendSignature(specialValueParamPrefix(it))
+                mangleValueParameter(this, it)
+            }
         }
+
         typeParameters.collectForMangler(builder, MangleConstant.TYPE_PARAMETERS) { mangleTypeParameter(this, it) }
 
         if (!isCtor && !returnType.isUnit() && addReturnType()) {
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/mangle/mangleUtils.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/mangle/mangleUtils.kt
index 2ec132b7ebb..784eab43f55 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/mangle/mangleUtils.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/mangle/mangleUtils.kt
@@ -12,14 +12,25 @@ fun <T> Collection<T>.collectForMangler(builder: StringBuilder, params: MangleCo
 
     builder.append(params.prefix)
 
+    var addSeparator = true
+
     for (e in this) {
         if (first) {
             first = false
-        } else {
+        } else if (addSeparator) {
             builder.append(params.separator)
         }
 
+        val l = builder.length
         builder.collect(e)
+        addSeparator = l < builder.length
+    }
+
+    if (!addSeparator) {
+        if (builder.last() == params.separator) {
+            // avoid signatures like foo(Int;)
+            builder.deleteCharAt(builder.lastIndex)
+        }
     }
 
     builder.append(params.suffix)