From df988e83f60a886b623202505c9a02e907851a84 Mon Sep 17 00:00:00 2001
From: Ryan Di <ryan.weihao.di@gmail.com>
Date: Thu, 20 Mar 2025 20:30:33 +1100
Subject: [PATCH] keep lasso if selected from toolbar

---
 packages/excalidraw/actions/actionCanvas.tsx |  1 +
 packages/excalidraw/appState.ts              |  1 +
 packages/excalidraw/components/App.tsx       | 12 +++++++++---
 packages/excalidraw/types.ts                 |  2 ++
 packages/excalidraw/utils.ts                 |  3 ++-
 5 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/packages/excalidraw/actions/actionCanvas.tsx b/packages/excalidraw/actions/actionCanvas.tsx
index f261ab947..642c58b1f 100644
--- a/packages/excalidraw/actions/actionCanvas.tsx
+++ b/packages/excalidraw/actions/actionCanvas.tsx
@@ -532,6 +532,7 @@ export const actionToggleLassoTool = register({
     if (appState.activeTool.type !== "lasso") {
       activeTool = updateActiveTool(appState, {
         type: "lasso",
+        fromSelection: false,
       });
       setCursor(app.interactiveCanvas, CURSOR_TYPE.CROSSHAIR);
     } else {
diff --git a/packages/excalidraw/appState.ts b/packages/excalidraw/appState.ts
index c56ba9acb..2cb4eadb1 100644
--- a/packages/excalidraw/appState.ts
+++ b/packages/excalidraw/appState.ts
@@ -52,6 +52,7 @@ export const getDefaultAppState = (): Omit<
       type: "selection",
       customType: null,
       locked: DEFAULT_ELEMENT_PROPS.locked,
+      fromSelection: false,
       lastActiveTool: null,
     },
     penMode: false,
diff --git a/packages/excalidraw/components/App.tsx b/packages/excalidraw/components/App.tsx
index 01af409c5..d79f3de45 100644
--- a/packages/excalidraw/components/App.tsx
+++ b/packages/excalidraw/components/App.tsx
@@ -4696,7 +4696,7 @@ class App extends React.Component<AppProps, AppState> {
             }
         )
       | { type: "custom"; customType: string }
-    ) & { locked?: boolean },
+    ) & { locked?: boolean; fromSelection?: boolean },
   ) => {
     if (!this.isToolSupported(tool.type)) {
       console.warn(
@@ -8592,7 +8592,7 @@ class App extends React.Component<AppProps, AppState> {
         pointerDownState.lastCoords.x = pointerCoords.x;
         pointerDownState.lastCoords.y = pointerCoords.y;
         if (event.altKey) {
-          this.setActiveTool({ type: "lasso" });
+          this.setActiveTool({ type: "lasso", fromSelection: true });
           this.lassoTrail.startPath(pointerCoords.x, pointerCoords.y);
           this.setAppState({
             selectionElement: null,
@@ -9684,7 +9684,13 @@ class App extends React.Component<AppProps, AppState> {
         return;
       }
 
-      if (!activeTool.locked && activeTool.type !== "freedraw") {
+      if (
+        !activeTool.locked &&
+        activeTool.type !== "freedraw" &&
+        // if lasso is turned on but from selection => reset to selection
+        activeTool.type === "lasso" &&
+        activeTool.fromSelection
+      ) {
         resetCursor(this.interactiveCanvas);
         this.setState({
           newElement: null,
diff --git a/packages/excalidraw/types.ts b/packages/excalidraw/types.ts
index 0462658c9..91ab5c636 100644
--- a/packages/excalidraw/types.ts
+++ b/packages/excalidraw/types.ts
@@ -300,6 +300,8 @@ export interface AppState {
      */
     lastActiveTool: ActiveTool | null;
     locked: boolean;
+    // indicates if the current tool is temporarily switched on from the selection tool
+    fromSelection: boolean;
   } & ActiveTool;
   penMode: boolean;
   penDetected: boolean;
diff --git a/packages/excalidraw/utils.ts b/packages/excalidraw/utils.ts
index 84f6637f1..76029c260 100644
--- a/packages/excalidraw/utils.ts
+++ b/packages/excalidraw/utils.ts
@@ -382,7 +382,7 @@ export const updateActiveTool = (
         type: ToolType;
       }
     | { type: "custom"; customType: string }
-  ) & { locked?: boolean }) & {
+  ) & { locked?: boolean; fromSelection?: boolean }) & {
     lastActiveToolBeforeEraser?: ActiveTool | null;
   },
 ): AppState["activeTool"] => {
@@ -404,6 +404,7 @@ export const updateActiveTool = (
     type: data.type,
     customType: null,
     locked: data.locked ?? appState.activeTool.locked,
+    fromSelection: data.fromSelection ?? false,
   };
 };