From 9dd6efeb46ee7a004716f5c89501d11bda9861bb Mon Sep 17 00:00:00 2001
From: Yan Zhulanow <yan.zhulanow@jetbrains.com>
Date: Fri, 19 Oct 2018 20:48:42 +0300
Subject: [PATCH] Fix sporadic false-positive "Receiver parameter is never
 used" for local functions (KT-26481)

---
 .../UnusedReceiverParameterInspection.kt      |  2 +-
 .../unusedReceiverParameter/kt26481.kt        | 20 +++++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)
 create mode 100644 idea/testData/inspections/unusedReceiverParameter/kt26481.kt

diff --git a/idea/src/org/jetbrains/kotlin/idea/inspections/UnusedReceiverParameterInspection.kt b/idea/src/org/jetbrains/kotlin/idea/inspections/UnusedReceiverParameterInspection.kt
index 184e9d16d30..0024951fd32 100644
--- a/idea/src/org/jetbrains/kotlin/idea/inspections/UnusedReceiverParameterInspection.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/inspections/UnusedReceiverParameterInspection.kt
@@ -76,7 +76,7 @@ class UnusedReceiverParameterInspection : AbstractKotlinInspection() {
                 val receiverTypeDeclaration = receiverType.constructor.declarationDescriptor
                 if (DescriptorUtils.isCompanionObject(receiverTypeDeclaration)) return
 
-                val callable = callableDeclaration.descriptor ?: return
+                val callable = context[BindingContext.DECLARATION_TO_DESCRIPTOR, callableDeclaration] ?: return
 
                 if (callableDeclaration.isMainFunction(callable)) return
 
diff --git a/idea/testData/inspections/unusedReceiverParameter/kt26481.kt b/idea/testData/inspections/unusedReceiverParameter/kt26481.kt
new file mode 100644
index 00000000000..d85ca779d92
--- /dev/null
+++ b/idea/testData/inspections/unusedReceiverParameter/kt26481.kt
@@ -0,0 +1,20 @@
+class My(val x: Int)
+class Your(val x: Int)
+
+fun Your.foo(): Int {
+    println(x)
+    fun My.bar(): Int {
+        return x
+    }
+    return My(0).bar() + x
+}
+
+fun bar() {
+    fun String.foo() = this.length
+    "".foo()
+}
+
+fun baz() {
+    fun String.foo() = length
+    "".foo()
+}
\ No newline at end of file