From efc831e0ba66fb2c44acfc150d359a9a8cf56cab Mon Sep 17 00:00:00 2001
From: Andy <anhans@microsoft.com>
Date: Thu, 25 Oct 2018 12:25:33 -0700
Subject: [PATCH] At '.' in array literal, don't close the array (#28120)

---
 src/compiler/parser.ts                                |  6 ++++--
 .../completionsDotInArrayLiteralInObjectLiteral.ts    | 11 +++++++++++
 2 files changed, 15 insertions(+), 2 deletions(-)
 create mode 100644 tests/cases/fourslash/completionsDotInArrayLiteralInObjectLiteral.ts

diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index c88aebe799f..edb4835ae5f 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -1518,8 +1518,10 @@ namespace ts {
                 case ParsingContext.TypeParameters:
                     return isIdentifier();
                 case ParsingContext.ArrayLiteralMembers:
-                    if (token() === SyntaxKind.CommaToken) {
-                        return true;
+                    switch (token()) {
+                        case SyntaxKind.CommaToken:
+                        case SyntaxKind.DotToken: // Not an array literal member, but don't want to close the array (see `tests/cases/fourslash/completionsDotInArrayLiteralInObjectLiteral.ts`)
+                            return true;
                     }
                     // falls through
                 case ParsingContext.ArgumentExpressions:
diff --git a/tests/cases/fourslash/completionsDotInArrayLiteralInObjectLiteral.ts b/tests/cases/fourslash/completionsDotInArrayLiteralInObjectLiteral.ts
new file mode 100644
index 00000000000..8d679b36168
--- /dev/null
+++ b/tests/cases/fourslash/completionsDotInArrayLiteralInObjectLiteral.ts
@@ -0,0 +1,11 @@
+/// <reference path="fourslash.ts" />
+
+////const o = { x: [[|.|][||]/**/
+
+const [r0, r1] = test.ranges();
+verify.getSyntacticDiagnostics([
+    { code: 1109, message: "Expression expected.", range: r0 },
+    { code: 1003, message: "Identifier expected.", range: r1 },
+]);
+
+verify.completions({ marker: "", exact: undefined });