Handle unnamed default exports like anonymous functions (fixes #3040) (…

…#3053)

src/rules/spaceBeforeFunctionParenRule.ts

@@ -116,8 +116,8 @@ function getOption(node: ts.Node, options: Options): Option | undefined {
             return options.constructor;
 
         case ts.SyntaxKind.FunctionDeclaration:
-            return options.named;
-
+            // name is optional for function declaration which is default export (TS will emit error in other cases).
+            // Can be handled in the same way as function expression.
         case ts.SyntaxKind.FunctionExpression:
             return (node as ts.FunctionExpression).name !== undefined ? options.named : options.anonymous;
 

test/rules/space-before-function-paren/always/test.ts.fix

@@ -22,6 +22,9 @@ var f = function foobar (): void{
 var f = function foobar (a: string, cb: ()=>{}): void{};
 
 
+// Default export (name ommited)
+export default function () {}
+
 // Async Arrow
 // ignore
 () => {};

test/rules/space-before-function-paren/always/test.ts.lint

@@ -34,6 +34,10 @@ var f = function foobar(a: string, cb: ()=>{}): void{};
                        ~  [space-before-function-paren]
 
 
+// Default export (name ommited)
+export default function() {}
+                       ~  [space-before-function-paren]
+
 // Async Arrow
 // ignore
 () => {};

test/rules/space-before-function-paren/mixed/test.ts.fix

@@ -16,6 +16,8 @@ var f = function foobar(): void{
 };
 var f = function foobar(a: string, cb: ()=>{}): void{};
 
+// Default export (name ommited)
+export default function () {}
 
 // Async Arrow
 // ignore

test/rules/space-before-function-paren/mixed/test.ts.lint

@@ -25,6 +25,9 @@ var f = function foobar (): void{
 var f = function foobar (a: string, cb: ()=>{}): void{};
                        ~  [invalid-space]
 
+// Default export (name ommited)
+export default function() {}
+                       ~  [missing-space]
 
 // Async Arrow
 // ignore

test/rules/space-before-function-paren/never/test.ts.fix

@@ -21,6 +21,8 @@ var f = function foobar(): void{
 };
 var f = function foobar(a: string, cb: ()=>{}): void{};
 
+// Default export (name ommited)
+export default function() {}
 
 // Async Arrow
 // ignore

test/rules/space-before-function-paren/never/test.ts.lint

@@ -33,6 +33,9 @@ var f = function foobar (): void{
 var f = function foobar (a: string, cb: ()=>{}): void{};
                        ~ [0]
 
+// Default export (name ommited)
+export default function () {}
+                       ~ [0]
 
 // Async Arrow
 // ignore