fix unnecessary Reference Check with property signature

Author: Kingwl

src/compiler/checker.ts

@@ -1175,6 +1175,10 @@ namespace ts {
                         return true;
                     }
 
+                    if (isComputedPropertyName(current) && isPropertySignature(current.parent) && current.parent.name === current) {
+                        return true;
+                    }
+
                     const initializerOfProperty = current.parent &&
                         current.parent.kind === SyntaxKind.PropertyDeclaration &&
                         (<PropertyDeclaration>current.parent).initializer === current;

tests/baselines/reference/unnecessaryReferenceChecksWithPropertySignature.js

@@ -0,0 +1,16 @@
+//// [unnecessaryReferenceChecksWithPropertySignature.ts]
+interface C {
+  [C.a](): void;
+  [C.b]: void;
+}
+class C {
+  static readonly a = Symbol();
+  static readonly b = Symbol();
+}
+
+
+//// [unnecessaryReferenceChecksWithPropertySignature.js]
+class C {
+}
+C.a = Symbol();
+C.b = Symbol();

tests/baselines/reference/unnecessaryReferenceChecksWithPropertySignature.symbols

@@ -0,0 +1,28 @@
+=== tests/cases/compiler/unnecessaryReferenceChecksWithPropertySignature.ts ===
+interface C {
+>C : Symbol(C, Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 0, 0), Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 3, 1))
+
+  [C.a](): void;
+>[C.a] : Symbol(C[C.a], Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 0, 13))
+>C.a : Symbol(C.a, Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 4, 9))
+>C : Symbol(C, Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 0, 0), Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 3, 1))
+>a : Symbol(C.a, Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 4, 9))
+
+  [C.b]: void;
+>[C.b] : Symbol(C[C.b], Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 1, 16))
+>C.b : Symbol(C.b, Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 5, 31))
+>C : Symbol(C, Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 0, 0), Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 3, 1))
+>b : Symbol(C.b, Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 5, 31))
+}
+class C {
+>C : Symbol(C, Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 0, 0), Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 3, 1))
+
+  static readonly a = Symbol();
+>a : Symbol(C.a, Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 4, 9))
+>Symbol : Symbol(Symbol, Decl(lib.es6.d.ts, --, --), Decl(lib.es6.d.ts, --, --), Decl(lib.es6.d.ts, --, --))
+
+  static readonly b = Symbol();
+>b : Symbol(C.b, Decl(unnecessaryReferenceChecksWithPropertySignature.ts, 5, 31))
+>Symbol : Symbol(Symbol, Decl(lib.es6.d.ts, --, --), Decl(lib.es6.d.ts, --, --), Decl(lib.es6.d.ts, --, --))
+}
+

tests/baselines/reference/unnecessaryReferenceChecksWithPropertySignature.types

@@ -0,0 +1,30 @@
+=== tests/cases/compiler/unnecessaryReferenceChecksWithPropertySignature.ts ===
+interface C {
+>C : C
+
+  [C.a](): void;
+>[C.a] : () => void
+>C.a : unique symbol
+>C : typeof C
+>a : unique symbol
+
+  [C.b]: void;
+>[C.b] : void
+>C.b : unique symbol
+>C : typeof C
+>b : unique symbol
+}
+class C {
+>C : C
+
+  static readonly a = Symbol();
+>a : unique symbol
+>Symbol() : unique symbol
+>Symbol : SymbolConstructor
+
+  static readonly b = Symbol();
+>b : unique symbol
+>Symbol() : unique symbol
+>Symbol : SymbolConstructor
+}
+

tests/cases/compiler/unnecessaryReferenceChecksWithPropertySignature.ts

@@ -0,0 +1,10 @@
+// @target: es6
+
+interface C {
+  [C.a](): void;
+  [C.b]: void;
+}
+class C {
+  static readonly a = Symbol();
+  static readonly b = Symbol();
+}