feat: extend subscriber handling to publish on all changes (including undo & redo)

Author: stee-re

XMLEditor.spec.ts

@@ -233,16 +233,6 @@ describe('XMLEditor', () => {
     expect(called).to.equal(1);
     expect(editor.past).to.have.lengthOf(1);
 
-    editor.undo();
-    expect(called).to.equal(1);
-    expect(editor.past).to.have.lengthOf(0);
-    expect(editor.future).to.have.lengthOf(1);
-
-    editor.redo();
-    expect(called).to.equal(1);
-    expect(editor.past).to.have.lengthOf(1);
-    expect(editor.future).to.have.lengthOf(0);
-
     const unsubscribed = unsubscribe();
     expect(unsubscribed).to.equal(callback);
 
@@ -252,6 +242,52 @@ describe('XMLEditor', () => {
     expect(editor.past).to.have.lengthOf(2);
   });
 
+  it('notifies subscribers on undo with the previous commit', () => {
+    const node = sclDoc.querySelector('Substation')!;
+    const edit = { node };
+
+    const subscriber = sinon.spy();
+
+    editor.subscribe(subscriber);
+
+    const firstCommit = editor.commit(edit, { title: 'first' });
+    sinon.assert.calledOnce(subscriber);
+    sinon.assert.calledWithExactly(subscriber, firstCommit);
+
+    const secondCommit = editor.commit(edit, { title: 'second' });
+    sinon.assert.calledTwice(subscriber);
+    sinon.assert.calledWithExactly(subscriber, secondCommit);
+
+    editor.undo();
+    sinon.assert.calledThrice(subscriber);
+    sinon.assert.calledWithExactly(subscriber, firstCommit);
+  });
+
+  it('notifies subscribers on redo with the redone commit', () => {
+    const node = sclDoc.querySelector('Substation')!;
+    const edit = { node };
+
+    const subscriber = sinon.spy();
+
+    editor.subscribe(subscriber);
+
+    const firstCommit = editor.commit(edit, { title: 'first' });
+    sinon.assert.calledOnce(subscriber);
+    sinon.assert.calledWithExactly(subscriber, firstCommit);
+
+    const secondCommit = editor.commit(edit, { title: 'second' });
+    sinon.assert.calledTwice(subscriber);
+    sinon.assert.calledWithExactly(subscriber, secondCommit);
+
+    editor.undo();
+    sinon.assert.calledThrice(subscriber);
+    sinon.assert.calledWithExactly(subscriber, firstCommit);
+
+    editor.redo();
+    sinon.assert.callCount(subscriber, 4);
+    sinon.assert.calledWithExactly(subscriber, secondCommit);
+  });
+
   it('unsubscribes the correct subscriber among many', () => {
     const node = sclDoc.querySelector('Substation')!;
     const edit = { node };

XMLEditor.ts

@@ -7,6 +7,8 @@ import {
   Transactor,
 } from '@omicronenergy/oscd-api';
 
+const EMPTY_COMMIT: Commit<EditV2> = { undo: [], redo: [] };
+
 export class XMLEditor implements Transactor<EditV2> {
   past: Commit<EditV2>[] = [];
   future: Commit<EditV2>[] = [];
@@ -36,6 +38,8 @@ export class XMLEditor implements Transactor<EditV2> {
     if (!commit) return;
     handleEdit(commit.undo);
     this.future.unshift(commit);
+    const previousCommit = this.past[this.past.length - 1] || EMPTY_COMMIT;
+    this.#subscribers.forEach(subscriber => subscriber(previousCommit));
     return commit;
   }
 
@@ -44,6 +48,7 @@ export class XMLEditor implements Transactor<EditV2> {
     if (!commit) return;
     handleEdit(commit.redo);
     this.past.push(commit);
+    this.#subscribers.forEach(subscriber => subscriber(commit));
     return commit;
   }