Ordering items in smart completion for function type

idea/src/org/jetbrains/jet/plugin/completion/smart/LambdaItems.kt

@@ -37,6 +37,7 @@ object LambdaItems {
             val lookupElement = LookupElementBuilder.create("{...}")
                     .withInsertHandler(ArtificialElementInsertHandler("{ ", " }", false))
                     .suppressAutoInsertion()
+                    .assignSmartCompletionPriority(SmartCompletionItemPriority.LAMBDA_NO_PARAMS)
                     .addTailAndNameSimilarity(functionExpectedInfos)
             lookupElement.putUserData(KotlinCompletionCharFilter.ACCEPT_OPENING_BRACE, true)
             collection.add(lookupElement)
@@ -53,6 +54,7 @@ object LambdaItems {
                                                insertLambdaTemplate(context, TextRange(offset, offset + placeholder.length), functionType)
                                            })
                         .suppressAutoInsertion()
+                        .assignSmartCompletionPriority(SmartCompletionItemPriority.LAMBDA)
                         .addTailAndNameSimilarity(functionExpectedInfos.filter { it.type == functionType })
                 lookupElement.putUserData(KotlinCompletionCharFilter.ACCEPT_OPENING_BRACE, true)
                 collection.add(lookupElement)

idea/src/org/jetbrains/jet/plugin/completion/smart/SmartCompletion.kt

@@ -251,7 +251,9 @@ class SmartCompletion(val expression: JetSimpleNameExpression,
                 }
             }
 
-            return lookupElement.addTailAndNameSimilarity(matchedExpectedInfos)
+            return lookupElement
+                    .assignSmartCompletionPriority(SmartCompletionItemPriority.FUNCTION_REFERENCE)
+                    .addTailAndNameSimilarity(matchedExpectedInfos)
         }
 
         if (descriptor is SimpleFunctionDescriptor) {

idea/src/org/jetbrains/jet/plugin/completion/smart/Utils.kt

@@ -204,6 +204,9 @@ enum class SmartCompletionItemPriority {
     STATIC_MEMBER
     INSTANTIATION
     ANONYMOUS_OBJECT
+    LAMBDA_NO_PARAMS
+    LAMBDA
+    FUNCTION_REFERENCE
 }
 
 val SMART_COMPLETION_ITEM_PRIORITY_KEY = Key<SmartCompletionItemPriority>("SMART_COMPLETION_ITEM_PRIORITY_KEY")

idea/testData/completion/weighers/smart/FunctionExpected.kt

@@ -0,0 +1,15 @@
+fun foo(filter: (String) -> Boolean) {}
+
+fun doFilter(s: String): Boolean = true
+fun x(s: String): Boolean = true
+
+fun bar(p: (String) -> Boolean) {
+    foo(<caret>)
+}
+
+// ORDER: ::doFilter
+// ORDER: p
+// ORDER: {...}
+// ORDER: { String -> ... }
+// ORDER: ::error
+// ORDER: ::x

idea/tests/org/jetbrains/jet/completion/weighers/SmartCompletionWeigherTestGenerated.java

@@ -36,6 +36,12 @@ public class SmartCompletionWeigherTestGenerated extends AbstractSmartCompletion
         JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/completion/weighers/smart"), Pattern.compile("^([^\\.]+)\\.kt$"), true);
     }
 
+    @TestMetadata("FunctionExpected.kt")
+    public void testFunctionExpected() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/weighers/smart/FunctionExpected.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("MultipleArgsItem.kt")
     public void testMultipleArgsItem() throws Exception {
         String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/weighers/smart/MultipleArgsItem.kt");