openAgent

1diff --git a/dist/model/FileTreeController.js b/dist/model/FileTreeController.js
2index 37c5d1ffedd5aff0258dec41b1b5cedb240aa3a6..365c42ef4c824bfd13d14f0d09226929af625c73 100644
3--- a/dist/model/FileTreeController.js
4+++ b/dist/model/FileTreeController.js
5@@ -1052,8 +1052,8 @@ var FileTreeController = class {
6 		this.#setExpandedPaths(expandedPaths);
7 		return focusCandidate ?? this.#focusedPath;
8 	}
9-	#emit() {
10-		for (const listener of this.#listeners) listener();
11+	#emit(event) {
12+		for (const listener of this.#listeners) listener(event);
13 	}
14 	#emitMutation(event) {
15 		this.#mutationListeners.get(event.operation)?.forEach((listener) => {
16@@ -1149,7 +1149,7 @@ var FileTreeController = class {
17 			const searchFocusCandidate = this.#searchValue != null && this.#searchValue.length > 0 ? this.#refreshActiveSearchState() : this.#searchValue === "" ? this.#focusedPath : focusPathCandidate;
18 			const shouldBuildFullProjection = this.#searchValue != null || event.operation !== "expand" && event.operation !== "collapse";
19 			this.#rebuildVisibleProjection(searchFocusCandidate, shouldBuildFullProjection);
20-			this.#emit();
21+			this.#emit(event);
22 			const mutationEvent = toTreesMutationEvent(event);
23 			if (mutationEvent != null) this.#emitMutation(mutationEvent);
24 		});
25diff --git a/dist/model/internalTypes.d.ts b/dist/model/internalTypes.d.ts
26index 5b0fdd5a3b483439ae256795f3dad5a32182ab78..073c6f21edc20ce5bd44b122fe02b83de802b887 100644
27--- a/dist/model/internalTypes.d.ts
28+++ b/dist/model/internalTypes.d.ts
29@@ -4,7 +4,10 @@ import { FileTreeCompositionOptions, FileTreePublicId, FileTreeRenderOptions, Fi
30 import { FileTreeController } from "./FileTreeController.js";
31 
32 //#region src/model/internalTypes.d.ts
33-type FileTreeControllerListener = () => void;
34+type FileTreeControllerListener = (event?: {
35+  operation: 'expand' | 'collapse';
36+  path: string;
37+}) => void;
38 interface FileTreeStickyRowCandidate {
39   row: FileTreeVisibleRow;
40   subtreeEndIndex: number;
41diff --git a/dist/model/publicTypes.d.ts b/dist/model/publicTypes.d.ts
42index 84a7e2d14f67c1aad8230f19a3426ab7403f378e..752e262e6d2d8a836931b7b83a93d89a75e6209c 100644
43--- a/dist/model/publicTypes.d.ts
44+++ b/dist/model/publicTypes.d.ts
45@@ -167,6 +167,10 @@ type FileTreeOptionSurface = FileTreeRenderOptions & {
46   gitStatus?: readonly GitStatusEntry[];
47   id?: string;
48   icons?: FileTreeIcons;
49+  onExpansionChange?: (change: {
50+    expanded: boolean;
51+    path: FileTreePublicId;
52+  }) => void;
53   onSelectionChange?: FileTreeSelectionChangeListener;
54   renderRowDecoration?: FileTreeRowDecorationRenderer;
55   search?: boolean;
56diff --git a/dist/render/FileTree.js b/dist/render/FileTree.js
57index 6db15e51b833192f79b71a15febe1612a4c185d0..36a4e6ac527595849c1db0e6bbebb475b6030b7b 100644
58--- a/dist/render/FileTree.js
59+++ b/dist/render/FileTree.js
60@@ -63,6 +63,7 @@ var FileTree = class {
61 	#composition;
62 	#controller;
63 	#id;
64+	#onExpansionChange;
65 	#onSelectionChange;
66 	#renderRowDecoration;
67 	#renamingEnabled;
68@@ -80,16 +81,18 @@ var FileTree = class {
69 	#appliedUnsafeCSS;
70 	#selectionVersion;
71 	#selectionSubscription = null;
72+	#expansionSubscription = null;
73 	#wrapper;
74 	#wroteHostItemHeight = false;
75 	#wroteHostDensityFactor = false;
76 	constructor(options) {
77-		const { composition, density, fileTreeSearchMode, gitStatus, id, initialSearchQuery, icons, itemHeight, onSearchChange, onSelectionChange, overscan, renderRowDecoration, renaming, search, searchBlurBehavior, searchFakeFocus, stickyFolders, unsafeCSS, initialVisibleRowCount,...controllerOptions } = options;
78+		const { composition, density, fileTreeSearchMode, gitStatus, id, initialSearchQuery, icons, itemHeight, onExpansionChange, onSearchChange, onSelectionChange, overscan, renderRowDecoration, renaming, search, searchBlurBehavior, searchFakeFocus, stickyFolders, unsafeCSS, initialVisibleRowCount,...controllerOptions } = options;
79 		this.#composition = composition;
80 		this.#id = createClientId(id);
81 		this.#gitStatusState = resolveFileTreeGitStatusState(gitStatus);
82 		this.#icons = icons;
83 		this.#unsafeCSS = unsafeCSS;
84+		this.#onExpansionChange = onExpansionChange;
85 		this.#onSelectionChange = onSelectionChange;
86 		this.#renderRowDecoration = renderRowDecoration;
87 		this.#renamingEnabled = renaming != null && renaming !== false;
88@@ -114,6 +117,10 @@ var FileTree = class {
89 		this.#selectionSubscription = this.#onSelectionChange == null ? null : this.subscribe(() => {
90 			this.#emitSelectionChange();
91 		});
92+		this.#expansionSubscription = this.#onExpansionChange == null ? null : this.#controller.subscribe((event) => {
93+			if (event?.operation !== "expand" && event?.operation !== "collapse") return;
94+			this.#onExpansionChange?.({ path: event.path, expanded: event.operation === "expand" });
95+		});
96 	}
97 	unmount() {
98 		if (this.#wrapper != null) {
99@@ -133,6 +140,8 @@ var FileTree = class {
100 		this.unmount();
101 		this.#selectionSubscription?.();
102 		this.#selectionSubscription = null;
103+		this.#expansionSubscription?.();
104+		this.#expansionSubscription = null;
105 		this.#controller.destroy();
106 	}
107 	getFileTreeContainer() {
108