Merge pull request #14508 from Busyrev/fix-function-parameter-default-value

FIX: #14507 Function parameter default value wrongly emmited by Printer

Author: mhegazy

src/compiler/emitter.ts

@@ -819,8 +819,8 @@ namespace ts {
             writeIfPresent(node.dotDotDotToken, "...");
             emit(node.name);
             writeIfPresent(node.questionToken, "?");
-            emitExpressionWithPrefix(" = ", node.initializer);
             emitWithPrefix(": ", node.type);
+            emitExpressionWithPrefix(" = ", node.initializer);
         }
 
         function emitDecorator(decorator: Decorator) {

src/harness/unittests/printer.ts

@@ -45,6 +45,9 @@ namespace ts {
 
                 // comment9
                 console.log(1 + 2);
+
+                // comment10
+                function functionWithDefaultArgValue(argument: string = "defaultValue"): void { }
             `, ScriptTarget.ES2015);
 
             printsCorrectly("default", {}, printer => printer.printFile(sourceFile));

tests/baselines/reference/printerApi/printsFileCorrectly.default.js

@@ -23,3 +23,5 @@ const enum E2 {
 }
 // comment9
 console.log(1 + 2);
+// comment10
+function functionWithDefaultArgValue(argument: string = "defaultValue"): void { }

tests/baselines/reference/printerApi/printsFileCorrectly.removeComments.js

@@ -15,3 +15,4 @@ const enum E2 {
     second
 }
 console.log(1 + 2);
+function functionWithDefaultArgValue(argument: string = "defaultValue"): void { }