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f67b915855
I found a bug in queries using a like function in the where clause, ex:
`SELECT first_name, last_name FROM users WHERE like('Jas%', first_name)
= 1`. That panicked with the message:
```
thread 'main' panicked at core/vdbe/mod.rs:1226:33:
internal error: entered unreachable code: Like on non-text registers
```
This was caused by an off-by-one error in the vdbe code for executing a
`ScalarFunc::Like`. However, this only happened in where-like-fn
queries. Queries using the like operator (ex: `SELECT first_name,
last_name FROM users WHERE first_name LIKE 'Jas%'`) did not have this
problem.
I did some digging around, looked at the explains for these queries from
both limbo and sqlite, and it turns out, for binary expressions, limbo
positions the arguments in the register differently, which is the
ultimate root cause of this problem.
For the where-like-fn query, before execution limbo's registers look
like this:
```
[Null, Null, Integer(1), Text("Jas%"), Text("Jason"), Null, Null]
^the rhs 1 ^pattern ^haystack str
```
Sqlite's look look something like this:
```
[Null, Null, Text("Jas%"), Text("Jason"), Integer(1), Null, Null]
^pattern ^haystack str ^the rhs 1
```
Ultimately limbo's execution of scalar like function was looking in
positions 2 and 3 always, but because we stored the right-hand-side
before the like-fn arguments, there was an off-by-one error, and the
non-text register it was finding was the `Integer(1)`.
This PR changes the binary expression translation to allocate the right-
hand-side register *after* translating the left-hand-side, fixing the
off-by-one and matching sqlite's register layout.
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes #321