Reject invalid row/col index in table row and column commands

Found while testing crates/engine/src/cmd/table.rs:234-238 (at), via crates/engine/src/cmd/mod.rs:318 (usize_param)

Co-Authored-By: Claude Haiku 5.5 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

crates/engine/src/cmd/table.rs

@@ -231,10 +231,11 @@ fn cell_param(p: &Value, key: &str) -> Option<(usize, usize)> {
 }
 
 /// The table's row/col to act on: params, the edited cell, or the selected cells.
-fn at(s: &Session, p: &Value) -> (usize, usize) {
+/// A present but invalid `row`/`col` is an error; only an absent one falls back.
+fn at(s: &Session, p: &Value, cmd: &str) -> Result<(usize, usize)> {
     let st = s.active();
     let cell = st.and_then(|d| d.selection.text.as_ref().and_then(|t| t.cell)).or_else(|| st.and_then(|d| d.selection.cells.map(|c| c.1)));
-    (usize_param(p, "row").or(cell.map(|c| c.0)).unwrap_or(0), usize_param(p, "col").or(cell.map(|c| c.1)).unwrap_or(0))
+    Ok((opt_usize_param(p, "row", cmd)?.or(cell.map(|c| c.0)).unwrap_or(0), opt_usize_param(p, "col", cmd)?.or(cell.map(|c| c.1)).unwrap_or(0)))
 }
 
 fn with_table(s: &mut Session, p: &Value, cmd: &str, f: impl Fn(&mut Table) -> Result<()>) -> Result<Value> {
@@ -283,7 +284,7 @@ fn with_table(s: &mut Session, p: &Value, cmd: &str, f: impl Fn(&mut Table) -> R
 }
 
 fn rows_cols(s: &mut Session, p: &Value, op: &str) -> Result<Value> {
-    let (r, c) = at(s, p);
+    let (r, c) = at(s, p, &format!("table.{op}"))?;
     let op = op.to_string();
     with_table(s, p, "table", move |t| {
         match op.as_str() {
@@ -319,7 +320,10 @@ fn merge(s: &mut Session, p: &Value) -> Result<Value> {
 }
 
 fn split(s: &mut Session, p: &Value) -> Result<Value> {
-    let cell = cell_param(p, "cell").unwrap_or_else(|| at(s, p));
+    let cell = match cell_param(p, "cell") {
+        Some(c) => c,
+        None => at(s, p, "table.split")?,
+    };
     with_table(s, p, "table.split", move |t| if t.split(cell.0, cell.1) { Ok(()) } else { Err(bad("table.split", "that cell isn't merged")) })
 }
 
@@ -531,7 +535,7 @@ fn distribute(s: &mut Session, p: &Value, rows: bool) -> Result<Value> {
 }
 
 fn column_width(s: &mut Session, p: &Value) -> Result<Value> {
-    let (_, c) = at(s, p);
+    let (_, c) = at(s, p, "table.columnWidth")?;
     let w = f64_param(p, "width").ok_or_else(|| bad("table.columnWidth", "missing `width`"))?.clamp(4.0, 4000.0);
     let keep_total = bool_or(p, "keepTotal", false);
     with_table(s, p, "table.columnWidth", move |t| {
@@ -560,7 +564,7 @@ fn column_width(s: &mut Session, p: &Value) -> Result<Value> {
 }
 
 fn row_height(s: &mut Session, p: &Value) -> Result<Value> {
-    let (r, _) = at(s, p);
+    let (r, _) = at(s, p, "table.rowHeight")?;
     let h = f64_param(p, "height").ok_or_else(|| bad("table.rowHeight", "missing `height`"))?.clamp(4.0, 4000.0);
     with_table(s, p, "table.rowHeight", move |t| {
         if let Some(x) = t.rows.get_mut(r) {

crates/engine/src/tests.rs

@@ -3672,6 +3672,26 @@ fn table_insert_below_or_right_of_a_huge_index_appends_at_the_end() {
     assert_eq!(t.cell(0, 1).unwrap().text.text(), "b", "the original columns keep their place");
 }
 
+#[test]
+fn table_row_col_commands_reject_an_invalid_index() {
+    let mut s = session();
+    let id = table_at(&mut s, &[100.0, 100.0], json!([["a", "b"], ["c", "d"], ["e", "f"]]));
+    for (cmd, key) in [
+        ("table.deleteRow", "row"),
+        ("table.deleteColumn", "col"),
+        ("table.insertRowAbove", "row"),
+        ("table.insertColumnLeft", "col"),
+        ("table.split", "row"),
+    ] {
+        for bad in [json!(-1), json!(1.5), json!("1")] {
+            let r = s.execute(cmd, &json!({"id": id.0, key: bad}));
+            assert!(r.is_err(), "{cmd} {key}={bad} should be rejected, got {r:?}");
+            let t = table_of(&s, id);
+            assert_eq!((t.n_rows(), t.n_cols()), (3, 2), "{cmd} {key}={bad} must leave the table unchanged");
+        }
+    }
+}
+
 #[test]
 fn table_column_width_of_a_huge_column_is_ignored() {
     let mut s = session();