Formatting problem in VSCode

[spike7638]

Please include steps needed to reproduce the bug, along any relevant sections of the log file, located at node_modules/.lsp/debug.log

The following code (written by a student solving an exam problem) shows up with peculiar formatting at line 14:

type cbst = Leaf | Node((value, count), cbst, cbst);

let rec largestCount: cbst => int =
inTree =>
switch (inTree) {
| Leaf => failwith("largestCount does not take empty CBST")
| Node((_val1, c1), Leaf, Leaf) => c1
| Node((_val1, c1), leftSide, Leaf) =>
if (c1 >= largestCount(leftSide)) {
c1;
} else {
largestCount(leftSide);
}
| Node((_val1, c1), Leaf, rightSide) => // PECULIAR FORMATTING
if (c1 >= largestCount(rightSide)) {
c1;
} else {
largestCount(rightSide);
}
| Node((_val1, c1), leftSide, rightSide) =>
if (c1 >= largestCount(leftSide) && c1 >= largestCount(rightSide)) {
c1;
} else if (largestCount(leftSide) >= c1
&& largestCount(leftSide) >= largestCount(rightSide)) {
largestCount(leftSide);
} else {
largestCount(rightSide);
}
};

The word "_val1" at lines 7 and 8 is highlighted in green, with the following c1 in each case highlighted in red. But at line 15, only the "1" in "_val1" is highlighted green, and the c1 is just in black like most other text in the program.
If we place lines 9-13 in a block, though, like this

type cbst = Leaf | Node((value, count), cbst, cbst);

let rec largestCount: cbst => int =
inTree =>
switch (inTree) {
| Leaf => failwith("largestCount does not take empty CBST")
| Node((_val1, c1), Leaf, Leaf) => c1
| Node((_val1, c1), leftSide, Leaf) =>
{ //ADDED
if (c1 >= largestCount(leftSide)) {
c1;
} else {
largestCount(leftSide);
}
} //ADDED
| Node((_val1, c1), Leaf, rightSide) =>
if (c1 >= largestCount(rightSide)) {
c1;
} else {
largestCount(rightSide);
}
| Node((_val1, c1), leftSide, rightSide) =>
if (c1 >= largestCount(leftSide) && c1 >= largestCount(rightSide)) {
c1;
} else if (largestCount(leftSide) >= c1
&& largestCount(leftSide) >= largestCount(rightSide)) {
largestCount(leftSide);
} else {
debug.log

    largestCount(rightSide);
  }
};

then the highlighting looks right again. On the other hand, reformatting the document (select-all, right-click, Format Document) leads to those new braces getting removed, and the coloring problem renews itself.