From 81774926fa4a9f9ba7f8c961be6f50a855832092 Mon Sep 17 00:00:00 2001
From: Alexander Udalov <Alexander.Udalov@jetbrains.com>
Date: Mon, 20 Mar 2017 14:41:23 +0300
Subject: [PATCH] Discriminate header class in resolution from sources in
 AbstractLazyMemberScope

Similarly to getFirstClassifierDiscriminateHeaders, we select the first
non-header class if possible, otherwise we select just the first class.
This makes sure that a reference will never be resolved to a header
class if the corresponding impl class is present.

Note that overall the issue may not be fixed yet, because there are
other scopes where header classes are not yet discriminated
(LazyImportScope, DeserializedMemberScope). However, at this point I
cannot reproduce this problem with these other scopes

 #KT-15521 Fixed
---
 .../lazy/descriptors/AbstractLazyMemberScope.kt      | 12 +++++++++---
 .../createImplClassInPlatformModule/common.kt        |  1 +
 .../createImplClassInPlatformModule/jvm.kt           |  7 +++++++
 .../createImplClassInPlatformModule/output.txt       |  7 +++++++
 .../MultiPlatformIntegrationTestGenerated.java       |  6 ++++++
 5 files changed, 30 insertions(+), 3 deletions(-)
 create mode 100644 compiler/testData/multiplatform/createImplClassInPlatformModule/common.kt
 create mode 100644 compiler/testData/multiplatform/createImplClassInPlatformModule/jvm.kt
 create mode 100644 compiler/testData/multiplatform/createImplClassInPlatformModule/output.txt

diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/AbstractLazyMemberScope.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/AbstractLazyMemberScope.kt
index 10650f3da99..fcf786e8137 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/AbstractLazyMemberScope.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/AbstractLazyMemberScope.kt
@@ -66,9 +66,15 @@ protected constructor(
     override fun getContributedClassifier(name: Name, location: LookupLocation): ClassifierDescriptor? {
         recordLookup(name, location)
         // NB we should resolve type alias descriptors even if a class descriptor with corresponding name is present
-        val firstClassDescriptor = classDescriptors(name).firstOrNull()
-        val firstTypeAliasDescriptor = typeAliasDescriptors(name).firstOrNull()
-        return firstClassDescriptor ?: firstTypeAliasDescriptor
+        val classes = classDescriptors(name)
+        val typeAliases = typeAliasDescriptors(name)
+        var resultingClass: ClassDescriptor? = null
+        for (klass in classes) {
+            // See getFirstClassifierDiscriminateHeaders()
+            if (!klass.isHeader) return klass
+            if (resultingClass == null) resultingClass = klass
+        }
+        return resultingClass ?: typeAliases.firstOrNull()
     }
 
     override fun getContributedFunctions(name: Name, location: LookupLocation): Collection<SimpleFunctionDescriptor> {
diff --git a/compiler/testData/multiplatform/createImplClassInPlatformModule/common.kt b/compiler/testData/multiplatform/createImplClassInPlatformModule/common.kt
new file mode 100644
index 00000000000..b7b0f1b26c6
--- /dev/null
+++ b/compiler/testData/multiplatform/createImplClassInPlatformModule/common.kt
@@ -0,0 +1 @@
+header class Foo
diff --git a/compiler/testData/multiplatform/createImplClassInPlatformModule/jvm.kt b/compiler/testData/multiplatform/createImplClassInPlatformModule/jvm.kt
new file mode 100644
index 00000000000..5abb848dd57
--- /dev/null
+++ b/compiler/testData/multiplatform/createImplClassInPlatformModule/jvm.kt
@@ -0,0 +1,7 @@
+impl class Foo(x: Int) {
+    impl constructor() : this(0)
+
+    val x: Int = x
+}
+
+val y = Foo(42).x
diff --git a/compiler/testData/multiplatform/createImplClassInPlatformModule/output.txt b/compiler/testData/multiplatform/createImplClassInPlatformModule/output.txt
new file mode 100644
index 00000000000..b08950d503d
--- /dev/null
+++ b/compiler/testData/multiplatform/createImplClassInPlatformModule/output.txt
@@ -0,0 +1,7 @@
+-- Common --
+Exit code: OK
+Output:
+
+-- JVM --
+Exit code: OK
+Output:
diff --git a/compiler/tests/org/jetbrains/kotlin/multiplatform/MultiPlatformIntegrationTestGenerated.java b/compiler/tests/org/jetbrains/kotlin/multiplatform/MultiPlatformIntegrationTestGenerated.java
index c79106a88c0..1884cdd59bc 100644
--- a/compiler/tests/org/jetbrains/kotlin/multiplatform/MultiPlatformIntegrationTestGenerated.java
+++ b/compiler/tests/org/jetbrains/kotlin/multiplatform/MultiPlatformIntegrationTestGenerated.java
@@ -42,6 +42,12 @@ public class MultiPlatformIntegrationTestGenerated extends AbstractMultiPlatform
         doTest(fileName);
     }
 
+    @TestMetadata("createImplClassInPlatformModule")
+    public void testCreateImplClassInPlatformModule() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/multiplatform/createImplClassInPlatformModule/");
+        doTest(fileName);
+    }
+
     @TestMetadata("genericDeclarations")
     public void testGenericDeclarations() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/multiplatform/genericDeclarations/");