"Remove redundant let": fix destructuring declaration false positive

#KT-26042 Fixed

idea/src/org/jetbrains/kotlin/idea/intentions/ReplaceSingleLineLetIntention.kt

@@ -17,6 +17,7 @@
 package org.jetbrains.kotlin.idea.intentions
 
 import com.intellij.openapi.editor.Editor
+import org.jetbrains.kotlin.descriptors.impl.ValueParameterDescriptorImpl
 import org.jetbrains.kotlin.idea.caches.resolve.analyze
 import org.jetbrains.kotlin.idea.core.replaced
 import org.jetbrains.kotlin.idea.inspections.IntentionBasedInspection
@@ -105,11 +106,20 @@ class ReplaceSingleLineLetIntention : SelfTargetingOffsetIndependentIntention<Kt
         val bodyExpression = lambdaExpression.bodyExpression?.children?.singleOrNull() ?: return false
 
         return when (bodyExpression) {
-            is KtBinaryExpression -> element.parent !is KtSafeQualifiedExpression && bodyExpression.isApplicable(parameterName)
-            is KtDotQualifiedExpression -> bodyExpression.isApplicable(parameterName)
-            is KtCallExpression -> element.parent !is KtSafeQualifiedExpression
-                    && lambdaExpression.functionLiteral.valueParameterReferences(bodyExpression).count() <= 1
-            else -> false
+            is KtBinaryExpression ->
+                element.parent !is KtSafeQualifiedExpression && bodyExpression.isApplicable(parameterName)
+            is KtDotQualifiedExpression ->
+                bodyExpression.isApplicable(parameterName)
+            is KtCallExpression ->
+                if (element.parent is KtSafeQualifiedExpression) {
+                    false
+                } else {
+                    val count = lambdaExpression.functionLiteral.valueParameterReferences(bodyExpression).count()
+                    val destructuringDeclaration = lambdaExpression.functionLiteral.valueParameters.firstOrNull()?.destructuringDeclaration
+                    count == 0 || (count == 1 && destructuringDeclaration == null)
+                }
+            else ->
+                false
         }
     }
 
@@ -163,13 +173,17 @@ class ReplaceSingleLineLetIntention : SelfTargetingOffsetIndependentIntention<Kt
     private fun KtExpression.nameUsed(name: String, except: KtNameReferenceExpression? = null): Boolean =
         anyDescendantOfType<KtNameReferenceExpression> { it != except && it.getReferencedName() == name }
 
-    private fun KtFunctionLiteral.valueParameterReferences(callExpression: KtCallExpression): List<KtReferenceExpression> {
+    private fun KtFunctionLiteral.valueParameterReferences(callExpression: KtCallExpression): List<KtNameReferenceExpression> {
         val context = analyze(BodyResolveMode.PARTIAL)
-        val descriptor = context[BindingContext.FUNCTION, this]?.valueParameters?.singleOrNull() ?: return emptyList()
-        val name = descriptor.name.asString()
+        val parameterDescriptor = context[BindingContext.FUNCTION, this]?.valueParameters?.singleOrNull() ?: return emptyList()
+        val variableDescriptorByName = if (parameterDescriptor is ValueParameterDescriptorImpl.WithDestructuringDeclaration)
+            parameterDescriptor.destructuringVariables.associate { it.name to it }
+        else
+            mapOf(parameterDescriptor.name to parameterDescriptor)
         return callExpression.valueArguments.flatMap { arg ->
-            arg.collectDescendantsOfType<KtReferenceExpression>().filter {
-                it.text == name && it.getResolvedCall(context)?.resultingDescriptor == descriptor
+            arg.collectDescendantsOfType<KtNameReferenceExpression>().filter {
+                val descriptor = variableDescriptorByName[it.getReferencedNameAsName()]
+                descriptor != null && it.getResolvedCall(context)?.resultingDescriptor == descriptor
             }
         }
     }

idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration.kt

@@ -0,0 +1,7 @@
+// WITH_RUNTIME
+
+fun test() {
+    (1 to 2).let<caret> { (i, j) -> foo() }
+}
+
+fun foo() = 0

idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration.kt.after

@@ -0,0 +1,7 @@
+// WITH_RUNTIME
+
+fun test() {
+    foo()
+}
+
+fun foo() = 0

idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration2.kt

@@ -0,0 +1,7 @@
+// WITH_RUNTIME
+
+fun test() {
+    (1 to 2).let<caret> { (i, j) -> foo(1, 2) }
+}
+
+fun foo(i: Int, j: Int) = i + j

idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration2.kt.after

@@ -0,0 +1,7 @@
+// WITH_RUNTIME
+
+fun test() {
+    foo(1, 2)
+}
+
+fun foo(i: Int, j: Int) = i + j

idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration3.kt

@@ -0,0 +1,8 @@
+// WITH_RUNTIME
+// IS_APPLICABLE: false
+
+fun test() {
+    (1 to 2).let<caret> { (i, j) -> foo(i, 3) }
+}
+
+fun foo(i: Int, j: Int) = i + j

idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration4.kt

@@ -0,0 +1,6 @@
+// WITH_RUNTIME
+// IS_APPLICABLE: false
+
+fun test(k: Int) {
+    (1 to 2).let<caret> { (i, j) -> i + k }
+}

idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration5.kt

@@ -0,0 +1,6 @@
+// WITH_RUNTIME
+// IS_APPLICABLE: false
+
+fun test() {
+    (1 to 2).let<caret> { (i, j) -> i.toLong() }
+}

idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTestGenerated.java

@@ -13912,6 +13912,31 @@ public class IntentionTestGenerated extends AbstractIntentionTest {
             runTest("idea/testData/intentions/replaceSingleLineLetIntention/comparisons.kt");
         }
 
+        @TestMetadata("destructuringDeclaration.kt")
+        public void testDestructuringDeclaration() throws Exception {
+            runTest("idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration.kt");
+        }
+
+        @TestMetadata("destructuringDeclaration2.kt")
+        public void testDestructuringDeclaration2() throws Exception {
+            runTest("idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration2.kt");
+        }
+
+        @TestMetadata("destructuringDeclaration3.kt")
+        public void testDestructuringDeclaration3() throws Exception {
+            runTest("idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration3.kt");
+        }
+
+        @TestMetadata("destructuringDeclaration4.kt")
+        public void testDestructuringDeclaration4() throws Exception {
+            runTest("idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration4.kt");
+        }
+
+        @TestMetadata("destructuringDeclaration5.kt")
+        public void testDestructuringDeclaration5() throws Exception {
+            runTest("idea/testData/intentions/replaceSingleLineLetIntention/destructuringDeclaration5.kt");
+        }
+
         @TestMetadata("dotWithComparison.kt")
         public void testDotWithComparison() throws Exception {
             runTest("idea/testData/intentions/replaceSingleLineLetIntention/dotWithComparison.kt");