Changed adding invalid as arg to empty callfunc invocations by default

bsconfig.schema.json

@@ -281,6 +281,11 @@
             "description": "Allow brighterscript features (classes, interfaces, etc...) to be included in BrightScript (`.brs`) files, and force those files to be transpiled.",
             "type": "boolean",
             "default": false
+        },
+        "legacyCallfuncHandling": {
+            "description": "Legacy RokuOS versions required at least a single argument in callfunc() invocations. Previous brighterscript versions handled this by inserting invalid as an argument when no other args are present. This is not necessary in modern RokuOS versions.",
+            "type": "boolean",
+            "default": false
         }
     }
 }

src/BsConfig.ts

@@ -195,6 +195,12 @@ export interface BsConfig {
      * scripts inside `source` that depend on bslib.brs.  Defaults to `source`.
      */
     bslibDestinationDir?: string;
+
+    /* Legacy RokuOS versions required at least a single argument in callfunc() invocations.
+     * Previous brighterscript versions handled this by inserting invalid as an argument when no other args are present.
+     * This is not necessary in modern RokuOS versions.
+     */
+    legacyCallfuncHandling?: boolean;
 }
 
 type OptionalBsConfigFields =

src/files/BrsFile.spec.ts

@@ -2613,7 +2613,8 @@ describe('BrsFile', () => {
                 expectZeroDiagnostics(program);
             });
 
-            it('sets invalid on empty callfunc', async () => {
+            it('sets invalid on empty callfunc with legacyCallfuncHandling=true', async () => {
+                program.options.legacyCallfuncHandling = true;
                 await testTranspile(`
                     sub main()
                         node = invalid
@@ -2631,6 +2632,24 @@ describe('BrsFile', () => {
                 `);
             });
 
+            it('empty callfunc allowed by default', async () => {
+                await testTranspile(`
+                    sub main()
+                        node = invalid
+                        node@.doSomething()
+                        m.top.node@.doSomething()
+                        m.top.node@.doSomething(1)
+                    end sub
+                `, `
+                    sub main()
+                        node = invalid
+                        node.callfunc("doSomething")
+                        m.top.node.callfunc("doSomething")
+                        m.top.node.callfunc("doSomething", 1)
+                    end sub
+                `);
+            });
+
             it('includes original arguments', async () => {
                 await testTranspile(`
                     sub main()

src/parser/Expression.ts

@@ -1140,14 +1140,11 @@ export class CallfuncExpression extends Expression {
             state.sourceNode(this.operator, '.callfunc'),
             state.transpileToken(this.openingParen),
             //the name of the function
-            state.sourceNode(this.methodName, ['"', this.methodName.text, '"']),
-            ', '
+            state.sourceNode(this.methodName, ['"', this.methodName.text, '"'])
         );
-        //transpile args
-        //callfunc with zero args never gets called, so pass invalid as the first parameter if there are no args
-        if (this.args.length === 0) {
-            result.push('invalid');
-        } else {
+        if (this.args?.length > 0) {
+            result.push(', ');
+            //transpile args
             for (let i = 0; i < this.args.length; i++) {
                 //add comma between args
                 if (i > 0) {
@@ -1156,7 +1153,10 @@ export class CallfuncExpression extends Expression {
                 let arg = this.args[i];
                 result.push(...arg.transpile(state));
             }
+        } else if (state.options.legacyCallfuncHandling) {
+            result.push(', ', 'invalid');
         }
+
         result.push(
             state.transpileToken(this.closingParen)
         );

src/util.ts

@@ -375,7 +375,8 @@ export class Util {
             emitDefinitions: config.emitDefinitions === true ? true : false,
             removeParameterTypes: config.removeParameterTypes === true ? true : false,
             logLevel: logLevel,
-            bslibDestinationDir: bslibDestinationDir
+            bslibDestinationDir: bslibDestinationDir,
+            legacyCallfuncHandling: config.legacyCallfuncHandling === true ? true : false
         };
 
         //mutate `config` in case anyone is holding a reference to the incomplete one