- Instead of changing the current directory with `env::set_current_dir`
to be implicitly inherited by subprocesses, we now use
`Command::current_dir` to set it explicitly. This feels much better,
since we aren't dependent on the implicit state of the process's
current directory.
- Subcommand execution is much improved.
- Added a ton of tests for config parsing, config execution, working
dir, and search dir.
- Error messages are improved. Many more will be colored.
- The Config is now onwed, instead of borrowing from the arguments and
the `clap::ArgMatches` object. This is a huge ergonomic improvement,
especially in tests, and I don't think anyone will notice.
- `--edit` now uses `$VISUAL`, `$EDITOR`, or `vim`, in that order,
matching git, which I think is what most people will expect.
- Added a cute `tmptree!{}` macro, for creating temporary directories
populated with directories and files for tests.
- Admitted that grammer is LL(k) and I don't know what `k` is.
- Refactor the lexer tests to be more readable, abandoning the
previous string-based summary DSL in favor of a more obvious
sequence of `TokenKinds` with optional lexemes. The new tests
also test that token lexemes are correct.
- Move duplicated `unindent` function into a shared crate,
`test-utilities`. This new versionless dev-dependency will
prevent publishing to crates.io, at least until rust-lang/cargo/pull/7333
makes it into stable. If we publish a new version before then,
test-utilities will need to be published to crates.io, so we can depend
on it by version.
