Remove excess comment ranges from initialized and property parameter emit

src/compiler/transformers/es2015.ts

@@ -1311,24 +1311,27 @@ namespace ts {
                     setTextRange(
                         createBlock([
                             createStatement(
-                                setTextRange(
-                                    createAssignment(
-                                        setEmitFlags(getMutableClone(name), EmitFlags.NoSourceMap),
-                                        setEmitFlags(initializer, EmitFlags.NoSourceMap | getEmitFlags(initializer))
+                                setEmitFlags(
+                                    setTextRange(
+                                        createAssignment(
+                                            setEmitFlags(getMutableClone(name), EmitFlags.NoSourceMap),
+                                            setEmitFlags(initializer, EmitFlags.NoSourceMap | getEmitFlags(initializer) | EmitFlags.NoComments)
+                                        ),
+                                        parameter
                                     ),
-                                    parameter
+                                    EmitFlags.NoComments
                                 )
                             )
                         ]),
                         parameter
                     ),
-                    EmitFlags.SingleLine | EmitFlags.NoTrailingSourceMap | EmitFlags.NoTokenSourceMaps
+                    EmitFlags.SingleLine | EmitFlags.NoTrailingSourceMap | EmitFlags.NoTokenSourceMaps | EmitFlags.NoComments
                 )
             );
 
             startOnNewLine(statement);
             setTextRange(statement, parameter);
-            setEmitFlags(statement, EmitFlags.NoTokenSourceMaps | EmitFlags.NoTrailingSourceMap | EmitFlags.CustomPrologue);
+            setEmitFlags(statement, EmitFlags.NoTokenSourceMaps | EmitFlags.NoTrailingSourceMap | EmitFlags.CustomPrologue | EmitFlags.NoComments);
             statements.push(statement);
         }
 

src/compiler/transformers/ts.ts

@@ -1147,20 +1147,23 @@ namespace ts {
             setEmitFlags(localName, EmitFlags.NoComments);
 
             return startOnNewLine(
-                setTextRange(
-                    createStatement(
-                        createAssignment(
-                            setTextRange(
-                                createPropertyAccess(
-                                    createThis(),
-                                    propertyName
+                setEmitFlags(
+                    setTextRange(
+                        createStatement(
+                            createAssignment(
+                                setTextRange(
+                                    createPropertyAccess(
+                                        createThis(),
+                                        propertyName
+                                    ),
+                                    node.name
                                 ),
-                                node.name
-                            ),
-                            localName
-                        )
+                                localName
+                            )
+                        ),
+                        moveRangePos(node, -1)
                     ),
-                    moveRangePos(node, -1)
+                    EmitFlags.NoComments
                 )
             );
         }

tests/baselines/reference/defaultParameterTrailingComments.js

@@ -0,0 +1,17 @@
+//// [defaultParameterTrailingComments.ts]
+class C {
+    constructor(defaultParam: boolean = false /* Emit only once*/) {}
+}
+
+function foo(defaultParam = 10 /*emit only once*/) {}
+
+//// [defaultParameterTrailingComments.js]
+var C = /** @class */ (function () {
+    function C(defaultParam /* Emit only once*/) {
+        if (defaultParam === void 0) { defaultParam = false; }
+    }
+    return C;
+}());
+function foo(defaultParam /*emit only once*/) {
+    if (defaultParam === void 0) { defaultParam = 10; }
+}

tests/baselines/reference/defaultParameterTrailingComments.symbols

@@ -0,0 +1,12 @@
+=== tests/cases/compiler/defaultParameterTrailingComments.ts ===
+class C {
+>C : Symbol(C, Decl(defaultParameterTrailingComments.ts, 0, 0))
+
+    constructor(defaultParam: boolean = false /* Emit only once*/) {}
+>defaultParam : Symbol(defaultParam, Decl(defaultParameterTrailingComments.ts, 1, 16))
+}
+
+function foo(defaultParam = 10 /*emit only once*/) {}
+>foo : Symbol(foo, Decl(defaultParameterTrailingComments.ts, 2, 1))
+>defaultParam : Symbol(defaultParam, Decl(defaultParameterTrailingComments.ts, 4, 13))
+

tests/baselines/reference/defaultParameterTrailingComments.types

@@ -0,0 +1,14 @@
+=== tests/cases/compiler/defaultParameterTrailingComments.ts ===
+class C {
+>C : C
+
+    constructor(defaultParam: boolean = false /* Emit only once*/) {}
+>defaultParam : boolean
+>false : false
+}
+
+function foo(defaultParam = 10 /*emit only once*/) {}
+>foo : (defaultParam?: number) => void
+>defaultParam : number
+>10 : 10
+

tests/baselines/reference/parameterReferenceInInitializer1.js

@@ -19,8 +19,8 @@ function fn(y, set) {
 var C = /** @class */ (function () {
     function C(y, x // expected to work, but actually doesn't
     ) {
-        if (x === void 0) { x = fn(y, function (y, x) { return y.x = x; }); } // expected to work, but actually doesn't
-        this.x = x; // expected to work, but actually doesn't
+        if (x === void 0) { x = fn(y, function (y, x) { return y.x = x; }); }
+        this.x = x;
     }
     return C;
 }());

tests/cases/compiler/defaultParameterTrailingComments.ts

@@ -0,0 +1,5 @@
+class C {
+    constructor(defaultParam: boolean = false /* Emit only once*/) {}
+}
+
+function foo(defaultParam = 10 /*emit only once*/) {}