There are two bugs in #1085.
1. `find_free_cell` accesses non-existent free blocks and returns their
size to `allocate_space`. This is out of range access error. The fix is
to add a loop termination condition that stops it when we hit the end of
the blocks
2. This bug is caused by `find_free_cell` some how swallowing the blocks
with size `4 bytes`. So `compute_free_space` consistently undercounts by
`4 bytes`. I've refactored that part of the code to make sure 4 sized
block are not deleted.
I've also added a unit test which proves these fixes work and also added
a function called `debug_print_freelist` which prints all free blocks of
a page.
For now I've silenced the `overflow_page` tests.
Fixes#1085Closes#1111
You might have guessed the `DumbLruCache` was dumb, but no, it was a
reference to myself. This PR fixes some dumb mistakes of detaching nodes
which failed to update `tail` and `head` properly.
Edit: This PR now fixes `Connection::execute` which funnily enough we
didn't notice it was returning successfully but in reality
`program.step` returned `IO` which made us think it was finished but not
really.
Edit 2: This PR fixes yet another thing! Pages read from WAL where being
initialized as if they were `id > 1`. By making it not this dumb thing
we can read `page 1` from `WAL` without failing catastrophically
Closes#1115
When I added frame reading support I thought, okay, who cares about the page id of this page it we read it from a frame because we don't need it to compute the offset to read from the file in this case. Fuck me, because it was needed in case we read `page 1` from WAL because it has a differnt `offset`.
Previously any block that has a size 4 is deleted resulting in the issue of computed free space
is less than 4 bytes when compared to expected free space.
This PR introduces test for SQLite3 API implementation, adding both unit
tests in Rust and maintaining existing C compatibility tests.
## Changes
- Added unit tests for core SQLite3 operations in `lib.rs`:
- Database initialization and shutdown
- Memory database operations
- Error code handling and messages
- Statement preparation and execution
- Version information verification
Closes#1108
