From 484758a3d3a252bd0c117b91aad37c94c851fea3 Mon Sep 17 00:00:00 2001
From: Andy <anhans@microsoft.com>
Date: Mon, 11 Dec 2017 09:45:36 -0800
Subject: [PATCH] Handle `!` following a keyword in isClassMemberStart (#20617)

* Handle `!` following a keyword in isClassMemberStart

* Fix test
---
 src/compiler/parser.ts                               |  1 +
 .../baselines/reference/parserIsClassMemberStart.js  | 12 ++++++++++++
 .../reference/parserIsClassMemberStart.symbols       |  8 ++++++++
 .../reference/parserIsClassMemberStart.types         |  8 ++++++++
 tests/cases/compiler/parserIsClassMemberStart.ts     |  3 +++
 5 files changed, 32 insertions(+)
 create mode 100644 tests/baselines/reference/parserIsClassMemberStart.js
 create mode 100644 tests/baselines/reference/parserIsClassMemberStart.symbols
 create mode 100644 tests/baselines/reference/parserIsClassMemberStart.types
 create mode 100644 tests/cases/compiler/parserIsClassMemberStart.ts

diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index cb28be4677a..52776f8e6a2 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -5462,6 +5462,7 @@ namespace ts {
                 switch (token()) {
                     case SyntaxKind.OpenParenToken:     // Method declaration
                     case SyntaxKind.LessThanToken:      // Generic Method declaration
+                    case SyntaxKind.ExclamationToken:   // Non-null assertion on property name
                     case SyntaxKind.ColonToken:         // Type Annotation for declaration
                     case SyntaxKind.EqualsToken:        // Initializer for declaration
                     case SyntaxKind.QuestionToken:      // Not valid, but permitted so that it gets caught later on.
diff --git a/tests/baselines/reference/parserIsClassMemberStart.js b/tests/baselines/reference/parserIsClassMemberStart.js
new file mode 100644
index 00000000000..7d57132aee9
--- /dev/null
+++ b/tests/baselines/reference/parserIsClassMemberStart.js
@@ -0,0 +1,12 @@
+//// [parserIsClassMemberStart.ts]
+class C {
+    type!: number;
+}
+
+
+//// [parserIsClassMemberStart.js]
+var C = /** @class */ (function () {
+    function C() {
+    }
+    return C;
+}());
diff --git a/tests/baselines/reference/parserIsClassMemberStart.symbols b/tests/baselines/reference/parserIsClassMemberStart.symbols
new file mode 100644
index 00000000000..72f73375921
--- /dev/null
+++ b/tests/baselines/reference/parserIsClassMemberStart.symbols
@@ -0,0 +1,8 @@
+=== tests/cases/compiler/parserIsClassMemberStart.ts ===
+class C {
+>C : Symbol(C, Decl(parserIsClassMemberStart.ts, 0, 0))
+
+    type!: number;
+>type : Symbol(C.type, Decl(parserIsClassMemberStart.ts, 0, 9))
+}
+
diff --git a/tests/baselines/reference/parserIsClassMemberStart.types b/tests/baselines/reference/parserIsClassMemberStart.types
new file mode 100644
index 00000000000..b6ad5974274
--- /dev/null
+++ b/tests/baselines/reference/parserIsClassMemberStart.types
@@ -0,0 +1,8 @@
+=== tests/cases/compiler/parserIsClassMemberStart.ts ===
+class C {
+>C : C
+
+    type!: number;
+>type : number
+}
+
diff --git a/tests/cases/compiler/parserIsClassMemberStart.ts b/tests/cases/compiler/parserIsClassMemberStart.ts
new file mode 100644
index 00000000000..b277451b345
--- /dev/null
+++ b/tests/cases/compiler/parserIsClassMemberStart.ts
@@ -0,0 +1,3 @@
+class C {
+    type!: number;
+}