Add proper tests for CI

[Manishearth]

It should cd to a test crate directory, that contains a single function which panics on an input of size 6 or something, then fuzz init, edit the fuzz target to call this function, run the fuzz target, and ensure a crashfile is produced of the correct length.

[Manishearth]

@ner0x652 want to work on this?

[0xcpu]

@Manishearth If it doesn't need beyond intermediate level of Rust knowledge, then YES! (tomorrow after work)

[Manishearth]

It would mostly be a shell script that does the steps above. We'd probably check in the test crate to be fuzzed.

[Manishearth]

Willing to help if you need any.

[0xcpu]

Good! 👍

[0xcpu]

@Manishearth left 2 links on IRC, in case you didn't see them here is what I wrote:
This is deploy.sh in scripts folder:

# This script leaves in /scripts, go to parent, this should be needed only locally
cd ..
mkdir etc && cd etc 
cargo new testcrate
cd testcrate

testcrate_lib_source="
pub fn test_func(slice: &[u8]) {
    if slice.len() == 7 {
        panic!(\"I'm afraid of number 7\");
    }
}
"
echo "$testcrate_lib_source" > src/lib.rs

cargo build
cargo-fuzz init

fuzzer_script_source="
#![no_main]
extern crate libfuzzer_sys;
extern crate testcrate;

use testcrate::test_func;

#[export_name=\"rust_fuzzer_test_input\"]
pub extern fn go(data: &[u8]) {
    test_func(data);
}
"
echo "$fuzzer_script_source" > fuzz/fuzzers/fuzzer_script_1.rs

cargo-fuzz run fuzzer_script_1

And this is the new travis.yml

language: rust

rust:
  - stable
  - beta
  - nightly

os:
  - linux

matrix:
  fast_finish: true

notifications:
  email: false

deploy:
  provider: script
  script: scripts/deploy.sh
  on:
    branch: master

Is this (close to) what you were thinking of?

[Manishearth]

Just check in the testcrate into etc/. Then, in the script, cd to the crate and fuzz it.

Also, use sed to replace the body of go() in the fuzz script instead of overwriting it wholesale. We need to be sure that changes to the template still work.

[Manishearth]

Fixed in #92 . Thanks, @ner0x652 !

[0xcpu]

Thank you @Manishearth , too!