[CodeCompletion] Bump the priority on keywords in the

experimental code-completion path. Move them right before "other module"
results. This is a bit of a hack. Ideally, we would have a much better
idea which keywords are actually legal/likely in a given context and
could prioritize them even more.  Since today we basically splat in all
the keywords, keep them below the current module results so they don't
overwhelm us.

rdar://problem/25119529

Author: benlangmuir

test/SourceKit/CodeComplete/complete_hide_low_priority.swift

@@ -26,9 +26,9 @@ func test(y: Int) {
 // NOHIDE: y
 // NOHIDE: z
 // NOHIDE: x
+// NOHIDE: import
 // NOHIDE: ModuleColor
 // NOHIDE: Int
-// NOHIDE: import
 
 func testType() {
   let x: #^TOP_LEVEL_TYPE_0^#

test/SourceKit/CodeComplete/complete_sort_order.swift

@@ -40,8 +40,8 @@ func test() {
 // CONTEXT: key.name: "foo(b:)"
 // CONTEXT-NOT: key.name:
 // CONTEXT: key.name: "test()"
-// CONTEXT: key.name: "AbsoluteValuable"
 // CONTEXT: key.name: "#column"
+// CONTEXT: key.name: "AbsoluteValuable"
 
 // RUN: %complete-test -tok=STMT_0 %s | FileCheck %s -check-prefix=STMT
 func test1() {
@@ -55,6 +55,29 @@ func test1() {
 // STMT: func
 // STMT: foo(a: Int)
 
+// RUN: %complete-test -tok=STMT_1 %s | FileCheck %s -check-prefix=STMT_1
+func test5() {
+  var retLocal: Int
+  #^STMT_1,r,ret,retur,return^#
+}
+// STMT_1-LABEL: Results for filterText: r [
+// STMT_1-NEXT:    retLocal
+// STMT_1-NEXT:    repeat
+// STMT_1-NEXT:    return
+// STMT_1-NEXT:    required
+// STMT_1: ]
+// STMT_1-LABEL: Results for filterText: ret [
+// STMT_1-NEXT:    retLocal
+// STMT_1-NEXT:    return
+// STMT_1-NEXT:    repeat
+// STMT_1: ]
+// STMT_1-LABEL: Results for filterText: retur [
+// STMT_1-NEXT:    return
+// STMT_1: ]
+// STMT_1-LABEL: Results for filterText: return [
+// STMT_1-NEXT:    return
+// STMT_1: ]
+
 // RUN: %complete-test -top=0 -tok=EXPR_0 %s | FileCheck %s -check-prefix=EXPR
 func test2() {
   (#^EXPR_0^#)

tools/SourceKit/lib/SwiftLang/CodeCompletionOrganizer.cpp

@@ -602,13 +602,17 @@ static double getSemanticContextScore(bool useImportDepth,
     if (useImportDepth && completion->getModuleImportDepth())
       depth = *completion->getModuleImportDepth();
     // We treat depth == 0 the same as CurrentModule.
+    // Note: there is a gap in between that we use for keywords.
     order = (depth == 0) ? 5.0 : 6.0; // Base value.
     order += double(depth) / (Completion::maxModuleImportDepth + 1);
     assert((depth == 0 && order == 5.0) ||
            (depth && 6.0 <= order && order <= 7.0));
     break;
   }
-  case SemanticContextKind::None: order = 8.0; break;
+  case SemanticContextKind::None: {
+    order = completion->getKind() == Completion::Keyword ? 5.5 : 8.0;
+    break;
+  }
   }
   assert(0.0 <= order && order <= 8.0);
   return (8.0 - order) / 8.0;