From 76307c0d024e754ead9cea4b957e57823b955f09 Mon Sep 17 00:00:00 2001
From: Jake Wang <jakezwang@users.noreply.github.com>
Date: Sat, 26 Sep 2026 18:38:59 -0400
Subject: [PATCH] fix(types): allow scriptable and indexed grid tick widths

Signed-off-by: Jake Wang <jakezwang@users.noreply.github.com>
---
 src/types/index.d.ts      |  2 +-
 test/types/scales/grid.ts | 25 +++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)
 create mode 100644 test/types/scales/grid.ts

diff --git a/src/types/index.d.ts b/src/types/index.d.ts
index 32831adc88c..9427f601d53 100644
--- a/src/types/index.d.ts
+++ b/src/types/index.d.ts
@@ -3101,7 +3101,7 @@ export interface GridLineOptions {
   /**
    * @default 1
    */
-  tickWidth: number;
+  tickWidth: ScriptableAndArray<number, ScriptableScaleContext>;
   /**
    * @default false
    */
diff --git a/test/types/scales/grid.ts b/test/types/scales/grid.ts
new file mode 100644
index 00000000000..e2f5e1e1949
--- /dev/null
+++ b/test/types/scales/grid.ts
@@ -0,0 +1,25 @@
+import { Chart, GridLineOptions, ScriptableScaleContext } from '../../../src/types.js';
+
+const grid: Partial<GridLineOptions> = {
+  tickWidth: (context: ScriptableScaleContext) => context.tick.value === 0 ? 2 : 1
+};
+
+const chart = new Chart('test', {
+  type: 'line',
+  data: { datasets: [] },
+  options: {
+    scales: {
+      x: { grid },
+      y: {
+        grid: {
+          tickWidth: (context) => {
+            const scaleContext: ScriptableScaleContext = context;
+            return scaleContext.tick.value === 0 ? 2 : 1;
+          }
+        }
+      },
+      y1: { grid: { tickWidth: [1, 2] } },
+      y2: { grid: { tickWidth: 2 } }
+    }
+  }
+});