fix: fix a bug when configurating the same extension multiple times

packages/core/src/Extension.ts

@@ -256,7 +256,9 @@ export class Extension<Options = any> {
   configure(options: Partial<Options> = {}) {
     this.options = mergeDeep(this.options, options) as Options
 
-    return this
+    // return a new instance so we can use the same extension
+    // with different calls of `configure`
+    return this.extend()
   }
 
   extend<ExtendedOptions = Options>(extendedConfig: Partial<ExtensionConfig<ExtendedOptions>> = {}) {

packages/core/src/Mark.ts

@@ -353,7 +353,9 @@ export class Mark<Options = any> {
   configure(options: Partial<Options> = {}) {
     this.options = mergeDeep(this.options, options) as Options
 
-    return this
+    // return a new instance so we can use the same extension
+    // with different calls of `configure`
+    return this.extend()
   }
 
   extend<ExtendedOptions = Options>(extendedConfig: Partial<MarkConfig<ExtendedOptions>> = {}) {

packages/core/src/Node.ts

@@ -434,7 +434,9 @@ export class Node<Options = any> {
   configure(options: Partial<Options> = {}) {
     this.options = mergeDeep(this.options, options) as Options
 
-    return this
+    // return a new instance so we can use the same extension
+    // with different calls of `configure`
+    return this.extend()
   }
 
   extend<ExtendedOptions = Options>(extendedConfig: Partial<NodeConfig<ExtendedOptions>> = {}) {

tests/cypress/integration/core/extensionOptions.spec.ts

@@ -121,4 +121,29 @@ describe('extension options', () => {
       },
     })
   })
+
+  it('should create its own instance on configure', () => {
+    const extension = Extension
+      .create({
+        defaultOptions: {
+          foo: 1,
+        },
+      })
+
+    const extension1 = extension.configure({
+      foo: 2,
+    })
+
+    const extension2 = extension.configure({
+      foo: 3,
+    })
+
+    expect(extension1.options).to.deep.eq({
+      foo: 2,
+    })
+
+    expect(extension2.options).to.deep.eq({
+      foo: 3,
+    })
+  })
 })