path: root/tests/common/mod.rs

#[cfg(test)]
#[allow(dead_code)]

extern crate growthring;
use growthring::wal::{WALFile, WALStore, WALPos, WALBytes};
use indexmap::{IndexMap, map::Entry};
use rand::Rng;
use std::collections::{HashMap, hash_map};
use std::cell::RefCell;
use std::rc::Rc;
use std::convert::TryInto;
use std::collections::VecDeque;

thread_local! {
    //pub static RNG: RefCell<rand::rngs::StdRng> = RefCell::new(<rand::rngs::StdRng as rand::SeedableRng>::from_seed([0; 32]));
    pub static RNG: RefCell<rand::rngs::ThreadRng> = RefCell::new(rand::thread_rng());
}

pub fn gen_rand_letters(i: usize) -> String {
    //let mut rng = rand::thread_rng();
    RNG.with(|rng| {
        (0..i).map(|_| (rng.borrow_mut().gen_range(0, 26) + 'a' as u8) as char).collect()
    })
}

struct FileContentEmul(RefCell<Vec<u8>>);

impl FileContentEmul {
    pub fn new() -> Self { FileContentEmul(RefCell::new(Vec::new())) }
}

impl std::ops::Deref for FileContentEmul {
    type Target = RefCell<Vec<u8>>;
    fn deref(&self) -> &Self::Target {&self.0}
}

pub trait FailGen {
    fn next_fail(&self) -> bool;
}

/// Emulate the a virtual file handle.
pub struct WALFileEmul<G: FailGen> {
    file: Rc<FileContentEmul>,
    fgen: Rc<G>
}

impl<G: FailGen> WALFile for WALFileEmul<G> {
    fn allocate(&self, offset: WALPos, length: usize) -> Result<(), ()> {
        if self.fgen.next_fail() { return Err(()) }
        let offset = offset as usize;
        if offset + length > self.file.borrow().len() {
            self.file.borrow_mut().resize(offset + length, 0)
        }
        for v in &mut self.file.borrow_mut()[offset..offset + length] { *v = 0 }
        Ok(())
    }

    fn truncate(&self, length: usize) -> Result<(), ()> {
        if self.fgen.next_fail() { return Err(()) }
        self.file.borrow_mut().resize(length, 0);
        Ok(())
    }

    fn write(&self, offset: WALPos, data: WALBytes) -> Result<(), ()> {
        if self.fgen.next_fail() { return Err(()) }
        let offset = offset as usize;
        &self.file.borrow_mut()[offset..offset + data.len()].copy_from_slice(&data);
        Ok(())
    }

    fn read(&self, offset: WALPos, length: usize) -> Result<Option<WALBytes>, ()> {
        if