# Description
Previously, only direcly-recursive calls were checked for recursion
depth. But most recursive calls in nushell are mutually recursive since
expressions like `for`, `where`, `try` and `do` all execute a separte
block.
```nushell
def f [] {
do { f }
}
```
Calling `f` would crash nushell with a stack overflow.
I think the only general way to prevent such a stack overflow is to
enforce a maximum call stack depth instead of only disallowing directly
recursive calls.
This commit also moves that logic into `eval_call()` instead of
`eval_block()` because the recursion limit is tracked in the `Stack`,
but not all blocks are evaluated in a new stack. Incrementing the
recursion depth of the caller's stack would permanently increment that
for all future calls.
Fixes#11667
# User-Facing Changes
Any function call can now fail with `recursion_limit_reached` instead of
just directly recursive calls. Mutually-recursive calls no longer crash
nushell.
# After Submitting
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