Add "unused equals" for direct calls without receiver

Related to KT-21192

idea/src/org/jetbrains/kotlin/idea/inspections/UnusedEqualsInspection.kt

@@ -23,6 +23,7 @@ import org.jetbrains.kotlin.idea.caches.resolve.analyze
 import org.jetbrains.kotlin.idea.intentions.conventionNameCalls.isAnyEquals
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
+import org.jetbrains.kotlin.psi.psiUtil.getQualifiedExpressionForSelectorOrThis
 import org.jetbrains.kotlin.resolve.bindingContextUtil.isUsedAsExpression
 import org.jetbrains.kotlin.util.OperatorNameConventions
 
@@ -48,15 +49,14 @@ class UnusedEqualsInspection : AbstractKotlinInspection() {
                 }
             }
 
-            override fun visitDotQualifiedExpression(expression: KtDotQualifiedExpression) {
-                super.visitDotQualifiedExpression(expression)
+            override fun visitCallExpression(expression: KtCallExpression) {
+                super.visitCallExpression(expression)
 
-                val callExpression = expression.selectorExpression as? KtCallExpression ?: return
-                val calleeExpression = callExpression.calleeExpression as? KtSimpleNameExpression ?: return
+                val calleeExpression = expression.calleeExpression as? KtSimpleNameExpression ?: return
                 if (calleeExpression.getReferencedNameAsName() != OperatorNameConventions.EQUALS) return
 
                 if (!expression.isAnyEquals()) return
-                reportIfNotUsedAsExpression(expression, calleeExpression)
+                reportIfNotUsedAsExpression(expression.getQualifiedExpressionForSelectorOrThis(), calleeExpression)
             }
         }
     }

idea/src/org/jetbrains/kotlin/idea/intentions/conventionNameCalls/ConventionUtils.kt

@@ -16,14 +16,21 @@
 
 package org.jetbrains.kotlin.idea.intentions.conventionNameCalls
 
-import org.jetbrains.kotlin.idea.intentions.toResolvedCall
-import org.jetbrains.kotlin.psi.KtDotQualifiedExpression
+import org.jetbrains.kotlin.descriptors.FunctionDescriptor
+import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.psi.KtExpression
+import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
 import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameUnsafe
 import org.jetbrains.kotlin.resolve.findOriginalTopMostOverriddenDescriptors
 import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
 
-fun KtDotQualifiedExpression.isAnyEquals(): Boolean {
-    val resolvedCall = toResolvedCall(BodyResolveMode.PARTIAL) ?: return false
-    val overriddenDescriptors = resolvedCall.resultingDescriptor.findOriginalTopMostOverriddenDescriptors()
+fun KtExpression.isAnyEquals(): Boolean {
+    val context = analyze(BodyResolveMode.PARTIAL)
+    val resolvedCall = getResolvedCall(context) ?: return false
+    return (resolvedCall.resultingDescriptor as? FunctionDescriptor)?.isAnyEquals() == true
+}
+
+fun FunctionDescriptor.isAnyEquals(): Boolean {
+    val overriddenDescriptors = findOriginalTopMostOverriddenDescriptors()
     return overriddenDescriptors.any { it.fqNameUnsafe.asString() == "kotlin.Any.equals" }
 }

idea/testData/inspections/unusedEquals/inspectionData/expected.xml

@@ -97,4 +97,13 @@
         <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused equals expression</problem_class>
         <description>Unused equals expression</description>
     </problem>
+
+    <problem>
+        <file>test.kt</file>
+        <line>81</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="temp:///src/test.kt" />
+        <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused equals expression</problem_class>
+        <description>Unused equals expression</description>
+    </problem>
 </problems>

idea/testData/inspections/unusedEquals/test.kt

@@ -75,6 +75,12 @@ fun foo9b() {
     consumer.ConsumerVoid<Any?> { it.equals(null) } // not used
 }
 
+fun myWith(it: Any?, f: Any?.() -> Unit) = it.f()
+
+fun foo9c() {
+    consumer.ConsumerVoid<Any?> { myWith (it) { equals(null) }} // not used
+}
+
 class Test(val successCondition: (Int) -> Boolean) {
     fun pass(num: Int): Boolean = successCondition(num)
 }