Fixed infinite recursion

idea/idea-analysis/src/org/jetbrains/kotlin/idea/search/usagesSearch/destructuringDeclarationUsages.kt

@@ -66,6 +66,10 @@ enum class DestructuringDeclarationUsageSearch {
 var destructuringDeclarationUsageSearchMode = if (ApplicationManager.getApplication().isUnitTestMode) ALWAYS_SMART else PLAIN_WHEN_NEEDED
 var destructuringDeclarationUsageSearchLog: MutableList<String>? = null
 
+private object DestructuringDeclarationSearchesInProgress : ThreadLocal<HashSet<KtDeclaration>>() {
+    override fun initialValue() = HashSet<KtDeclaration>()
+}
+
 //TODO: check if it's too expensive
 
 fun findDestructuringDeclarationUsages(
@@ -85,35 +89,43 @@ fun findDestructuringDeclarationUsages(
         consumer: Processor<PsiReference>,
         optimizer: SearchRequestCollector
 ) {
-    val usePlainSearch = when (destructuringDeclarationUsageSearchMode) {
+    val inProgress = DestructuringDeclarationSearchesInProgress.get()
-        ALWAYS_SMART -> false
+    try {
-        ALWAYS_PLAIN -> true
+        if (!inProgress.add(ktDeclaration)) return
-        PLAIN_WHEN_NEEDED -> scope is LocalSearchScope // for local scope it's faster to use plain search
-    }
-    if (usePlainSearch) {
-        doPlainSearch(ktDeclaration, scope, optimizer)
-        return
-    }
 
-    val descriptor = ktDeclaration.resolveToDescriptor() as? CallableDescriptor ?: return
+        val usePlainSearch = when (destructuringDeclarationUsageSearchMode) {
+            ALWAYS_SMART -> false
+            ALWAYS_PLAIN -> true
+            PLAIN_WHEN_NEEDED -> scope is LocalSearchScope // for local scope it's faster to use plain search
+        }
+        if (usePlainSearch) {
+            doPlainSearch(ktDeclaration, scope, optimizer)
+            return
+        }
 
-    if (descriptor is FunctionDescriptor && !descriptor.isValidOperator()) return
+        val descriptor = ktDeclaration.resolveToDescriptor() as? CallableDescriptor ?: return
 
-    val dataType = if (descriptor.isExtension) {
+        if (descriptor is FunctionDescriptor && !descriptor.isValidOperator()) return
-        descriptor.fuzzyExtensionReceiverType()!!
+
+        val dataType = if (descriptor.isExtension) {
+            descriptor.fuzzyExtensionReceiverType()!!
+        }
+        else {
+            val classDescriptor = descriptor.containingDeclaration as? ClassDescriptor ?: return
+            classDescriptor.defaultType.toFuzzyType(classDescriptor.typeConstructor.parameters)
+        }
+
+        Processor(dataType,
+                  ktDeclaration,
+                  scope,
+                  consumer,
+                  plainSearchHandler = { searchScope -> doPlainSearch(ktDeclaration, searchScope, optimizer) },
+                  testLog = destructuringDeclarationUsageSearchLog
+        ).run()
     }
-    else {
+    finally {
-        val classDescriptor = descriptor.containingDeclaration as? ClassDescriptor ?: return
+        inProgress.remove(ktDeclaration)
-        classDescriptor.defaultType.toFuzzyType(classDescriptor.typeConstructor.parameters)
     }
-
-    Processor(dataType,
-              ktDeclaration,
-              scope,
-              consumer,
-              plainSearchHandler = { searchScope -> doPlainSearch(ktDeclaration, searchScope, optimizer) },
-              testLog = destructuringDeclarationUsageSearchLog
-    ).run()
 }
 
 private fun doPlainSearch(ktDeclaration: KtDeclaration, scope: SearchScope, optimizer: SearchRequestCollector) {

idea/testData/findUsages/kotlin/conventions/components/recursiveDataClass1.0.kt

@@ -0,0 +1,10 @@
+// PSI_ELEMENT: org.jetbrains.kotlin.psi.KtParameter
+// OPTIONS: usages
+
+data class A(val <caret>a: A?, val n: Int)
+
+fun f(a: A) {
+    val (a1, n1) = a
+    val (a2, n2) =
+            a?.a ?: return
+}

idea/testData/findUsages/kotlin/conventions/components/recursiveDataClass1.log

@@ -0,0 +1,9 @@
+Checked type of (a1, n1)
+Checked type of (a2, n2)
+Checked type of (a2, n2)
+Searched inheritors of A
+Searched references to A
+Searched references to parameter a in A() in Kotlin files
+Searched references to parameter a in f() in Kotlin files
+Used plain search in LocalSearchScope:
+    CLASS:A

idea/testData/findUsages/kotlin/conventions/components/recursiveDataClass1.results.txt

@@ -0,0 +1,3 @@
+Value read 7 val (a1, n1) = a
+Value read 8 val (a2, n2) =
+Value read 9 a?.a ?: return

idea/testData/findUsages/kotlin/conventions/components/recursiveDataClass2.0.kt

@@ -0,0 +1,10 @@
+// PSI_ELEMENT: org.jetbrains.kotlin.psi.KtParameter
+// OPTIONS: usages
+
+data class A(val <caret>b: B, val n: Int)
+data class B(val a: A?, val s: String)
+
+fun f(a: A) {
+    val (b, n) = a
+    val (a1, s) = b
+}

idea/testData/findUsages/kotlin/conventions/components/recursiveDataClass2.log

@@ -0,0 +1,15 @@
+Checked type of (a1, s)
+Checked type of (b, n)
+Searched inheritors of A
+Searched inheritors of B
+Searched references to A
+Searched references to B
+Searched references to a1 in Kotlin files
+Searched references to b in Kotlin files
+Searched references to parameter a in B() in Kotlin files
+Searched references to parameter a in f() in Kotlin files
+Searched references to parameter b in A() in Kotlin files
+Used plain search in LocalSearchScope:
+    CLASS:A
+Used plain search in LocalSearchScope:
+    CLASS:B

idea/testData/findUsages/kotlin/conventions/components/recursiveDataClass2.results.txt

@@ -0,0 +1 @@
+Value read 8 val (b, n) = a

idea/tests/org/jetbrains/kotlin/findUsages/FindUsagesTestGenerated.java

@@ -254,6 +254,18 @@ public class FindUsagesTestGenerated extends AbstractFindUsagesTest {
                     doTest(fileName);
                 }
 
+                @TestMetadata("recursiveDataClass1.0.kt")
+                public void testRecursiveDataClass1() throws Exception {
+                    String fileName = KotlinTestUtils.navigationMetadata("idea/testData/findUsages/kotlin/conventions/components/recursiveDataClass1.0.kt");
+                    doTest(fileName);
+                }
+
+                @TestMetadata("recursiveDataClass2.0.kt")
+                public void testRecursiveDataClass2() throws Exception {
+                    String fileName = KotlinTestUtils.navigationMetadata("idea/testData/findUsages/kotlin/conventions/components/recursiveDataClass2.0.kt");
+                    doTest(fileName);
+                }
+
                 @TestMetadata("SAM.0.kt")
                 public void testSAM() throws Exception {
                     String fileName = KotlinTestUtils.navigationMetadata("idea/testData/findUsages/kotlin/conventions/components/SAM.0.kt");