From 8c4fdd1edd3cdcfc47c549611f113246fbc7ab7f Mon Sep 17 00:00:00 2001
From: Toshiaki Kameyama <kmymtsak@gmail.com>
Date: Tue, 8 Oct 2019 23:43:53 +0900
Subject: [PATCH] Unused import: do not report for 'invoke' function import
 that is used from same file

#KT-24281 Fixed
---
 .../KotlinUnusedImportInspection.kt            | 13 ++++++++++---
 .../quickfix/optimizeImports/invoke.kt         | 18 ++++++++++++++++++
 .../quickfix/optimizeImports/invoke2.kt        | 17 +++++++++++++++++
 .../quickfix/optimizeImports/invoke2.kt.after  | 15 +++++++++++++++
 .../idea/quickfix/QuickFixTestGenerated.java   | 10 ++++++++++
 5 files changed, 70 insertions(+), 3 deletions(-)
 create mode 100644 idea/testData/quickfix/optimizeImports/invoke.kt
 create mode 100644 idea/testData/quickfix/optimizeImports/invoke2.kt
 create mode 100644 idea/testData/quickfix/optimizeImports/invoke2.kt.after

diff --git a/idea/src/org/jetbrains/kotlin/idea/inspections/KotlinUnusedImportInspection.kt b/idea/src/org/jetbrains/kotlin/idea/inspections/KotlinUnusedImportInspection.kt
index 68619699b79..c96e2b76b45 100644
--- a/idea/src/org/jetbrains/kotlin/idea/inspections/KotlinUnusedImportInspection.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/inspections/KotlinUnusedImportInspection.kt
@@ -47,11 +47,12 @@ import org.jetbrains.kotlin.idea.core.targetDescriptors
 import org.jetbrains.kotlin.idea.imports.KotlinImportOptimizer
 import org.jetbrains.kotlin.idea.imports.OptimizedImportsBuilder
 import org.jetbrains.kotlin.idea.imports.importableFqName
+import org.jetbrains.kotlin.idea.references.KtInvokeFunctionReference
+import org.jetbrains.kotlin.idea.references.mainReference
+import org.jetbrains.kotlin.idea.search.usagesSearch.descriptor
 import org.jetbrains.kotlin.idea.util.ProjectRootsUtil
 import org.jetbrains.kotlin.name.FqName
-import org.jetbrains.kotlin.psi.KtCodeFragment
-import org.jetbrains.kotlin.psi.KtFile
-import org.jetbrains.kotlin.psi.KtImportDirective
+import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.siblings
 import org.jetbrains.kotlin.resolve.ImportPath
 
@@ -86,6 +87,11 @@ class KotlinUnusedImportInspection : AbstractKotlinInspection() {
                 }
             }
 
+            val invokeFunctionCallFqNames = optimizerData.references.mapNotNull {
+                val reference = (it.element as? KtCallExpression)?.mainReference as? KtInvokeFunctionReference ?: return@mapNotNull null
+                (reference.resolve() as? KtNamedFunction)?.descriptor?.importableFqName
+            }
+
             val importPaths = HashSet<ImportPath>(directives.size)
             val unusedImports = ArrayList<KtImportDirective>()
 
@@ -97,6 +103,7 @@ class KotlinUnusedImportInspection : AbstractKotlinInspection() {
                     !importPaths.add(importPath) -> false
                     importPath.isAllUnder -> importPath.fqName in parentFqNames
                     importPath.fqName in fqNames -> importPath.importedName?.let { it in fqNames.getValue(importPath.fqName) } ?: false
+                    importPath.fqName in invokeFunctionCallFqNames -> true
                     // case for type alias
                     else -> directive.targetDescriptors(resolutionFacade).firstOrNull()?.let { it.importableFqName in fqNames } ?: false
                 }
diff --git a/idea/testData/quickfix/optimizeImports/invoke.kt b/idea/testData/quickfix/optimizeImports/invoke.kt
new file mode 100644
index 00000000000..786590f5c81
--- /dev/null
+++ b/idea/testData/quickfix/optimizeImports/invoke.kt
@@ -0,0 +1,18 @@
+// "Optimize imports" "false"
+// WITH_RUNTIME
+// ACTION: Introduce import alias
+package ppp
+
+import ppp.invoke<caret>
+
+object Bar
+object Foo {
+    val bar = Bar
+}
+
+fun Foo.bar() = 1
+operator fun Bar.invoke() = 2
+
+fun main() {
+    println(Foo.bar())
+}
\ No newline at end of file
diff --git a/idea/testData/quickfix/optimizeImports/invoke2.kt b/idea/testData/quickfix/optimizeImports/invoke2.kt
new file mode 100644
index 00000000000..de4537dc859
--- /dev/null
+++ b/idea/testData/quickfix/optimizeImports/invoke2.kt
@@ -0,0 +1,17 @@
+// "Optimize imports" "true"
+// WITH_RUNTIME
+package ppp
+
+import ppp.invoke<caret>
+
+object Bar
+object Foo {
+    // val bar = Bar
+}
+
+fun Foo.bar() = 1
+operator fun Bar.invoke() = 2
+
+fun main() {
+    println(Foo.bar())
+}
\ No newline at end of file
diff --git a/idea/testData/quickfix/optimizeImports/invoke2.kt.after b/idea/testData/quickfix/optimizeImports/invoke2.kt.after
new file mode 100644
index 00000000000..7f83ce424ad
--- /dev/null
+++ b/idea/testData/quickfix/optimizeImports/invoke2.kt.after
@@ -0,0 +1,15 @@
+// "Optimize imports" "true"
+// WITH_RUNTIME
+package ppp
+
+object Bar
+object Foo {
+    // val bar = Bar
+}
+
+fun Foo.bar() = 1
+operator fun Bar.invoke() = 2
+
+fun main() {
+    println(Foo.bar())
+}
\ No newline at end of file
diff --git a/idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java b/idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java
index 675afddc91f..c89dcc9f2f5 100644
--- a/idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java
+++ b/idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java
@@ -9726,6 +9726,16 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
         public void testImportAlias() throws Exception {
             runTest("idea/testData/quickfix/optimizeImports/importAlias.kt");
         }
+
+        @TestMetadata("invoke.kt")
+        public void testInvoke() throws Exception {
+            runTest("idea/testData/quickfix/optimizeImports/invoke.kt");
+        }
+
+        @TestMetadata("invoke2.kt")
+        public void testInvoke2() throws Exception {
+            runTest("idea/testData/quickfix/optimizeImports/invoke2.kt");
+        }
     }
 
     @TestMetadata("idea/testData/quickfix/override")