From 27075555c84b6878ccc1cfa6b206426ee40b5a8c Mon Sep 17 00:00:00 2001
From: Wenlu Wang <kingwenlu@gmail.com>
Date: Tue, 23 Apr 2019 16:20:53 -0500
Subject: [PATCH] fix generate typenode from negative numerical literal
 (#30610)

---
 src/compiler/checker.ts                                  | 5 +++--
 .../codeFixClassImplementInterfaceWithNegativeNumber.ts  | 9 +++++++++
 tests/cases/fourslash/codeFixInferFromFunctionUsage.ts   | 9 +++++++++
 3 files changed, 21 insertions(+), 2 deletions(-)
 create mode 100644 tests/cases/fourslash/codeFixClassImplementInterfaceWithNegativeNumber.ts
 create mode 100644 tests/cases/fourslash/codeFixInferFromFunctionUsage.ts

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 9127a470325..22a658a0f7a 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -3484,8 +3484,9 @@ namespace ts {
                     return createLiteralTypeNode(setEmitFlags(createLiteral((<StringLiteralType>type).value), EmitFlags.NoAsciiEscaping));
                 }
                 if (type.flags & TypeFlags.NumberLiteral) {
-                    context.approximateLength += (("" + (<NumberLiteralType>type).value).length);
-                    return createLiteralTypeNode((createLiteral((<NumberLiteralType>type).value)));
+                    const value = (<NumberLiteralType>type).value;
+                    context.approximateLength += ("" + value).length;
+                    return createLiteralTypeNode(value < 0 ? createPrefix(SyntaxKind.MinusToken, createLiteral(-value)) : createLiteral(value));
                 }
                 if (type.flags & TypeFlags.BigIntLiteral) {
                     context.approximateLength += (pseudoBigIntToString((<BigIntLiteralType>type).value).length) + 1;
diff --git a/tests/cases/fourslash/codeFixClassImplementInterfaceWithNegativeNumber.ts b/tests/cases/fourslash/codeFixClassImplementInterfaceWithNegativeNumber.ts
new file mode 100644
index 00000000000..0fbce596d87
--- /dev/null
+++ b/tests/cases/fourslash/codeFixClassImplementInterfaceWithNegativeNumber.ts
@@ -0,0 +1,9 @@
+
+
+/// <reference path='fourslash.ts' />
+
+//// interface X { value: -1 | 0 | 1; }
+//// class Y implements X { }
+
+// https://github.com/Microsoft/TypeScript/issues/30431
+verify.codeFixAvailable([{ description: "Implement interface 'X'" }]);
diff --git a/tests/cases/fourslash/codeFixInferFromFunctionUsage.ts b/tests/cases/fourslash/codeFixInferFromFunctionUsage.ts
new file mode 100644
index 00000000000..27a039878ba
--- /dev/null
+++ b/tests/cases/fourslash/codeFixInferFromFunctionUsage.ts
@@ -0,0 +1,9 @@
+/// <reference path='fourslash.ts' />
+
+// @noImplicitAny: true
+////function wrap( [| arr |] ) {
+////     arr.sort(function (a: number, b: number) { return a < b ? -1 : 1 })
+//// }
+
+// https://github.com/Microsoft/TypeScript/issues/29330
+verify.rangeAfterCodeFix("arr: { sort: (arg0: (a: number, b: number) => 1 | -1) => void; }");