Handle promise passed where one is not expected

Author: davepagurek

src/core/friendly_errors/param_validator.js

@@ -352,7 +352,7 @@ function validateParams(p5, fn, lifecycles) {
    * @param {String} func - Name of the function. Expect global functions like `sin` and class methods like `p5.Vector.add`
    * @returns {String} The friendly error message.
    */
-  fn.friendlyParamError = function (zodErrorObj, func) {
+  fn.friendlyParamError = function (zodErrorObj, func, args) {
     let message = '🌸 p5.js says: ';
     // The `zodErrorObj` might contain multiple errors of equal importance
     // (after scoring the schema closeness in `findClosestSchema`). Here, we
@@ -398,6 +398,11 @@ function validateParams(p5, fn, lifecycles) {
       });
 
       if (expectedTypes.size > 0) {
+        if (error.path?.length > 0 && args[error.path[0]] instanceof Promise)  {
+          message += 'Did you mean to put `await` before a loading function? ' +
+            'An unexpected Promise was found. ';
+        }
+
         const expectedTypesStr = Array.from(expectedTypes).join(' or ');
         const position = error.path.join('.');
 
@@ -502,7 +507,7 @@ function validateParams(p5, fn, lifecycles) {
     } catch (error) {
       const closestSchema = fn.findClosestSchema(funcSchemas, args);
       const zodError = closestSchema.safeParse(args).error;
-      const errorMessage = fn.friendlyParamError(zodError, func);
+      const errorMessage = fn.friendlyParamError(zodError, func, args);
 
       return {
         success: false,

test/unit/core/param_errors.js

@@ -7,6 +7,21 @@ suite('Validate Params', function () {
     Color: function () {
       return 'mock p5.Color';
     },
+    Image: function() {
+      return 'mock p5.Image';
+    },
+    Element: function() {
+      return 'mock p5.Element';
+    },
+    Texture: function() {
+      return 'mock p5.Texture';
+    },
+    Framebuffer: function() {
+      return 'mock p5.Framebuffer';
+    },
+    FramebufferTexture: function() {
+      return 'mock p5.FramebufferTexture';
+    },
   };
   const mockP5Prototype = {};
 
@@ -102,6 +117,17 @@ suite('Validate Params', function () {
     });
   });
 
+  suite('validateParams: promise where no promise is expected', function () {
+    test('image(): promise for first argument', function () {
+      const result = mockP5Prototype.validate('p5.image', [Promise.resolve(), 0, 0]);
+      console.log(result);
+      assert.equal(
+        result.error,
+        '🌸 p5.js says: Did you mean to put `await` before a loading function? An unexpected Promise was found. Expected Image or Element or Texture or Framebuffer or FramebufferTexture at the first parameter in p5.image().'
+      );
+    });
+  });
+
   suite('validateParams: class, multi-types + optional numbers', function () {
     test('ambientLight(): no firendly-err-msg', function () {
       const result = mockP5Prototype.validate('p5.ambientLight', [new mockP5.Color()]);