From 4acd6cf90d1e2bf9848bebe8b062e2672db74689 Mon Sep 17 00:00:00 2001
From: dotCooCoo <RobertLeeLW@gmail.com>
Date: Fri, 13 Nov 2026 08:43:23 -0800
Subject: [PATCH] Batch: a step with null params gets the artboards a step
 without params gets

A `command.batch` step with `"params": null` now reads as a step without
params. Before, it got neither the Artboard tool's selected artboards nor
the batch's `artboard`, so a Fit to Artwork Bounds step fitted the first
artboard and its journal entry recorded `null`.
---
 crates/engine/src/cmd/fileio/batch.rs |  3 ++-
 crates/engine/src/tests/journal.rs    | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/crates/engine/src/cmd/fileio/batch.rs b/crates/engine/src/cmd/fileio/batch.rs
index 42512f18df..7b41894772 100644
--- a/crates/engine/src/cmd/fileio/batch.rs
+++ b/crates/engine/src/cmd/fileio/batch.rs
@@ -105,7 +105,8 @@ fn run_steps(
         if s.active().is_some() {
             s.begin_interaction(label)?;
         }
-        let mut params = c.get("params").cloned().unwrap_or(json!({}));
+        // `"params": null` reads as no params, so the artboards below can still be added.
+        let mut params = c.get("params").filter(|v| !v.is_null()).cloned().unwrap_or(json!({}));
         let key = if crate::ON_ACTIVE_ARTBOARD.contains(&id.as_str()) {
             Some("artboard")
         } else {
diff --git a/crates/engine/src/tests/journal.rs b/crates/engine/src/tests/journal.rs
index 2e31c24721..5b7c3b2322 100644
--- a/crates/engine/src/tests/journal.rs
+++ b/crates/engine/src/tests/journal.rs
@@ -299,6 +299,27 @@ fn a_batch_fit_step_records_the_batchs_artboard() {
     assert_eq!(s.journal_for_action(start), [("command.batch".to_string(), json!({"commands": steps}))]);
 }
 
+/// A batch step with `"params": null` gets the Artboard tool's selected artboards, or else the
+/// batch's `artboard`, as a step without params does.
+#[test]
+fn a_batch_fit_step_with_null_params_gets_the_artboards() {
+    let fitted = three_fitted_artboards();
+    let boards = |s: &Session| s.doc().unwrap().doc.artboards.iter().map(|a| a.rect).collect::<Vec<_>>();
+    let steps = json!([{"command": "artboard.fitToArt", "params": null}]);
+    let mut s = Session::new();
+    let was = three_artboards_with_art(&mut s);
+    s.select_tool("artboard", crate::tooling::ViewInfo::default()).unwrap();
+    s.set_tool_option("selected", &json!([2, 0]));
+    s.execute("command.batch", &json!({"artboard": 1, "commands": steps})).unwrap();
+    assert_eq!(boards(&s), [fitted[0], was[1], fitted[2]], "the selected artboards");
+    let (_, p) = s.journal.last().unwrap().clone();
+    assert_eq!(p["commands"][0]["params"], json!({"indices": [0, 2]}));
+    let mut s = Session::new();
+    three_artboards_with_art(&mut s);
+    s.execute("command.batch", &json!({"artboard": 1, "commands": steps})).unwrap();
+    assert_eq!(boards(&s), [was[0], fitted[1], was[2]], "the batch's artboard");
+}
+
 #[test]
 fn a_save_records_its_date_and_replays_it() {
     let path = vectorcraft_testkit::temp_dir("journal-save").join("a.vectorcraft").to_string_lossy().into_owned();