feat: disallow arrays as the object type

Author: kudashevs

src/ValidationError.js

@@ -234,7 +234,11 @@ function canApplyNot(schema) {
  * @returns {boolean}
  */
 function isObject(maybeObj) {
-  return typeof maybeObj === "object" && maybeObj !== null;
+  return (
+    typeof maybeObj === "object" &&
+    !Array.isArray(maybeObj) &&
+    maybeObj !== null
+  );
 }
 
 /**

test/__snapshots__/index.test.js.snap

@@ -1524,6 +1524,13 @@ exports[`Validation should fail validation for object in object with anyOf 1`] =
       [object { alias?, name?, onlyModule? }, ...]"
 `;
 
+exports[`Validation should fail validation for object type 1`] = `
+"Invalid configuration object. Object has been initialized using a configuration object that does not match the API schema.
+ - configuration.devServer should be an object:
+   object { … }
+   -> Options for the webpack-dev-server"
+`;
+
 exports[`Validation should fail validation for object with dependencies #2 1`] = `
 "Invalid configuration object. Object has been initialized using a configuration object that does not match the API schema.
  - configuration.objectWithPropertyDependency2 should be an object:

test/index.test.js

@@ -771,6 +771,14 @@ describe("Validation", () => {
     (msg) => expect(msg).toMatchSnapshot()
   );
 
+  createFailedTestCase(
+    "object type",
+    {
+      devServer: [],
+    },
+    (msg) => expect(msg).toMatchSnapshot()
+  );
+
   createFailedTestCase(
     "array type",
     {