## Summary
It's confusing that we use `constraints` here because constraints mean
something else for us (e.g., `--constraint constraints.txt`). These are
really the dependencies of a given `PubGrubPackage` -- the type is even
called `PubGrubDependencies`.
## Summary
I think this is overall good change because it explicitly encodes (in
the type system) something that was previously implicit. I'm not a huge
fan of the names here, open to input.
It covers some of https://github.com/astral-sh/uv/issues/3506 but I
don't think it _closes_ it.
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## Summary
Just fix typos.
While `alpha-numeric` is not really a misspelling:
- it is missing from mainstream curated dictionaries, all of them
suggest `alphanumeric`;
- it is less used than `alphanumeric` (more than ⨉10 less) according to
the Google [Ngram
Viewer](https://books.google.com/ngrams/graph?content=alpha-numeric%2Calphanumeric&year_start=1900&year_end=2019&corpus=en-2019);
- it is [missing from
SCOWL](http://app.aspell.net/lookup?dict=en_US-large;words=alpha-numeric).
## Test Plan
CI jobs.
## Summary
This PR consolidates the concurrency limits used throughout `uv` and
exposes two limits, `UV_CONCURRENT_DOWNLOADS` and
`UV_CONCURRENT_BUILDS`, as environment variables.
Currently, `uv` has a number of concurrent streams that it buffers using
relatively arbitrary limits for backpressure. However, many of these
limits are conflated. We run a relatively small number of tasks overall
and should start most things as soon as possible. What we really want to
limit are three separate operations:
- File I/O. This is managed by tokio's blocking pool and we should not
really have to worry about it.
- Network I/O.
- Python build processes.
Because the current limits span a broad range of tasks, it's possible
that a limit meant for network I/O is occupied by tasks performing
builds, reading from the file system, or even waiting on a `OnceMap`. We
also don't limit build processes that end up being required to perform a
download. While this may not pose a performance problem because our
limits are relatively high, it does mean that the limits do not do what
we want, making it tricky to expose them to users
(https://github.com/astral-sh/uv/issues/1205,
https://github.com/astral-sh/uv/issues/3311).
After this change, the limits on network I/O and build processes are
centralized and managed by semaphores. All other tasks are unbuffered
(note that these tasks are still bounded, so backpressure should not be
a problem).
This only makes hashes optional for wheels/sdists that come from
registires or direct URLs. For wheels/sdists that come from other
sources, a hash should not be present.
For path dependencies, a hash should not be present because the state of
the path dependency is not intended to be tracked in the lock file. This
is consistent with how other tools deal with path dependencies, and if
it were otherwise, the hash would I believe need to be updated for every
change to the path dependency.
For git dependencies (source dists only), a hash should not be present
because the lock will contain the specific commit revision hash. This is
functionally equivalent to a hash, and so a hash is redundant.
As part of this change, we validate the presence or absence of a hash
based on the dependency source. We also add our first regression tests.
This still keeps the resolver state on the stack, but it organizes it
into a more structured representation. This is a precursor to
implementing resolver forking, where we will ultimately put this state
on the heap. The idea is that this will let us maintain multiple
independent resolver states that will all produce their own resolution
(and potentially other forked states).
Closes#3354
We now use the getters and setters everywhere.
There were some places where we wanted to build a `MarkerEnvironment`
out of whole cloth, usually in tests. To facilitate those use cases, we
add a `MarkerEnvironmentBuilder` that provides a convenient constructor.
It's basically like a `MarkerEnvironment::new`, but with named
parameters. That's useful here because there are so many fields (and
they many have the same type).
This commit touches a lot of code, but the conceptual change here is
pretty simple: make it so we can run the resolver without providing a
`MarkerEnvironment`. This also indicates that the resolver should run in
universal mode. That is, the effect of a missing marker environment is
that all marker expressions that reference the marker environment are
evaluated to `true`. That is, they are ignored. (The only markers we
evaluate in that context are extras, which are the only markers that
aren't dependent on the environment.)
One interesting change here is that a `Resolver` no longer needs an
`Interpreter`. Previously, it had only been using it to construct a
`PythonRequirement`, by filling in the installed version from the
`Interpreter` state. But we now construct a `PythonRequirement`
explicitly since its `target` Python version should no longer be tied to
the `MarkerEnvironment`. (Currently, the marker environment is mutated
such that its `python_full_version` is derived from multiple sources,
including the CLI, which I found a touch confusing.)
The change in behavior can now be observed through the
`--unstable-uv-lock-file` flag. First, without it:
```
$ cat requirements.in
anyio>=4.3.0 ; sys_platform == "linux"
anyio<4 ; sys_platform == "darwin"
$ cargo run -qp uv -- pip compile -p3.10 requirements.in
anyio==4.3.0
exceptiongroup==1.2.1
# via anyio
idna==3.7
# via anyio
sniffio==1.3.1
# via anyio
typing-extensions==4.11.0
# via anyio
```
And now with it:
```
$ cargo run -qp uv -- pip compile -p3.10 requirements.in --unstable-uv-lock-file
x No solution found when resolving dependencies:
`-> Because you require anyio>=4.3.0 and anyio<4, we can conclude that the requirements are unsatisfiable.
```
This is expected at this point because the marker expressions are being
explicitly ignored, *and* there is no forking done yet to account for
the conflict.
## Summary
Fixes https://github.com/astral-sh/uv/issues/1343. This is kinda a first
draft at the moment, but does at least mostly work locally (barring some
bits of the test suite that seem to not work for me in general).
## Test Plan
Mostly running the existing tests and checking the revised output is
sane
## Outstanding issues
Most of these come down to "AFAIK, the existing tools don't support
these patterns, but `uv` does" and so I'm not sure there's an existing
good answer here! Most of the answers so far are "whatever was easiest
to build"
- [x] ~~Is "-r pyproject.toml" correct? Should it show something else or
get skipped entirely~~ No it wasn't. Fixed in
3044fa8b86
- [ ] If the requirements file is stdin, that just gets skipped. Should
it be recorded?
- [ ] Overrides get shown as "--override<override.txt>". Correct?
- [x] ~~Some of the tests (e.g.
`dependency_excludes_non_contiguous_range_of_compatible_versions`) make
assumptions about the order of package versions being outputted, which
this PR breaks. I'm not sure if the text is fairly arbitrary and can be
replaced or whether the behaviour needs fixing?~~ - fixed by removing
the custom pubgrub PartialEq/Hash
- [ ] Are all the `TrackedFromStr` et al changes needed, or is there an
easier way? I don't think so, I think it's necessary to track these sort
of things fairly comprehensively to make this feature work, and this
sort of invasive change feels necessary, but happy to be proved wrong
there :)
- [x] ~~If you have a requirement coming in from two or more different
requirements files only one turns up. I've got a closed-source example
for this (can go into more detail if needed), mostly consisting of a
complicated set of common deps creating a larger set. It's a rarer case,
but worth considering.~~ 042432b200
- [ ] Doesn't add annotations for `setup.py` yet
- This is pretty hard, as the correct location to insert the path is
`crates/pypi-types/src/metadata.rs`'s `parse_pkg_info`, which as it's
based off a source distribution has entirely thrown away such matters as
"where did this package requirement get built from". Could add "`built
package name`" as a dep, but that's a little odd.
Pubgrub got a new feature where all unavailability is a custom, instead
of the reasonless `UnavailableDependencies` and our custom `String` type
previously (https://github.com/pubgrub-rs/pubgrub/pull/208). This PR
introduces a `UnavailableReason` that tracks either an entire version
being unusable, or a specific version. The error messages now also track
this difference properly.
The pubgrub commit is our main rebased onto the merged
https://github.com/pubgrub-rs/pubgrub/pull/208, i'll push
`konsti/main-rebase-generic-reason` to `main` after checking for rebase
problems.
## Summary
All of the resolver code is run on the main thread, so a lot of the
`Send` bounds and uses of `DashMap` and `Arc` are unnecessary. We could
also switch to using single-threaded versions of `Mutex` and `Notify` in
some places, but there isn't really a crate that provides those I would
be comfortable with using.
The `Arc` in `OnceMap` can't easily be removed because of the uv-auth
code which uses the
[reqwest-middleware](https://docs.rs/reqwest-middleware/latest/reqwest_middleware/trait.Middleware.html)
crate, that seems to adds unnecessary `Send` bounds because of
`async-trait`. We could duplicate the code and create a `OnceMapLocal`
variant, but I don't feel that's worth it.
## Introduction
PEP 621 is limited. Specifically, it lacks
* Relative path support
* Editable support
* Workspace support
* Index pinning or any sort of index specification
The semantics of urls are a custom extension, PEP 440 does not specify
how to use git references or subdirectories, instead pip has a custom
stringly format. We need to somehow support these while still stying
compatible with PEP 621.
## `tool.uv.source`
Drawing inspiration from cargo, poetry and rye, we add `tool.uv.sources`
or (for now stub only) `tool.uv.workspace`:
```toml
[project]
name = "albatross"
version = "0.1.0"
dependencies = [
"tqdm >=4.66.2,<5",
"torch ==2.2.2",
"transformers[torch] >=4.39.3,<5",
"importlib_metadata >=7.1.0,<8; python_version < '3.10'",
"mollymawk ==0.1.0"
]
[tool.uv.sources]
tqdm = { git = "https://github.com/tqdm/tqdm", rev = "cc372d09dcd5a5eabdc6ed4cf365bdb0be004d44" }
importlib_metadata = { url = "https://github.com/python/importlib_metadata/archive/refs/tags/v7.1.0.zip" }
torch = { index = "torch-cu118" }
mollymawk = { workspace = true }
[tool.uv.workspace]
include = [
"packages/mollymawk"
]
[tool.uv.indexes]
torch-cu118 = "https://download.pytorch.org/whl/cu118"
```
See `docs/specifying_dependencies.md` for a detailed explanation of the
format. The basic gist is that `project.dependencies` is what ends up on
pypi, while `tool.uv.sources` are your non-published additions. We do
support the full range or PEP 508, we just hide it in the docs and
prefer the exploded table for easier readability and less confusing with
actual url parts.
This format should eventually be able to subsume requirements.txt's
current use cases. While we will continue to support the legacy `uv pip`
interface, this is a piece of the uv's own top level interface. Together
with `uv run` and a lockfile format, you should only need to write
`pyproject.toml` and do `uv run`, which generates/uses/updates your
lockfile behind the scenes, no more pip-style requirements involved. It
also lays the groundwork for implementing index pinning.
## Changes
This PR implements:
* Reading and lowering `project.dependencies`,
`project.optional-dependencies` and `tool.uv.sources` into a new
requirements format, including:
* Git dependencies
* Url dependencies
* Path dependencies, including relative and editable
* `pip install` integration
* Error reporting for invalid `tool.uv.sources`
* Json schema integration (works in pycharm, see below)
* Draft user-level docs (see `docs/specifying_dependencies.md`)
It does not implement:
* No `pip compile` testing, deprioritizing towards our own lockfile
* Index pinning (stub definitions only)
* Development dependencies
* Workspace support (stub definitions only)
* Overrides in pyproject.toml
* Patching/replacing dependencies
One technically breaking change is that we now require user provided
pyproject.toml to be valid wrt to PEP 621. Included files still fall
back to PEP 517. That means `pip install -r requirements.txt` requires
it to be valid while `pip install -r requirements.txt` with `-e .` as
content falls back to PEP 517 as before.
## Implementation
The `pep508` requirement is replaced by a new `UvRequirement` (name up
for bikeshedding, not particularly attached to the uv prefix). The still
existing `pep508_rs::Requirement` type is a url format copied from pip's
requirements.txt and doesn't appropriately capture all features we
want/need to support. The bulk of the diff is changing the requirement
type throughout the codebase.
We still use `VerbatimUrl` in many places, where we would expect a
parsed/decomposed url type, specifically:
* Reading core metadata except top level pyproject.toml files, we fail a
step later instead if the url isn't supported.
* Allowed `Urls`.
* `PackageId` with a custom `CanonicalUrl` comparison, instead of
canonicalizing urls eagerly.
* `PubGrubPackage`: We eventually convert the `VerbatimUrl` back to a
`Dist` (`Dist::from_url`), instead of remembering the url.
* Source dist types: We use verbatim url even though we know and require
that these are supported urls we can and have parsed.
I tried to make improve the situation be replacing `VerbatimUrl`, but
these changes would require massive invasive changes (see e.g.
https://github.com/astral-sh/uv/pull/3253). A main problem is the ref
`VersionOrUrl` and applying overrides, which assume the same
requirement/url type everywhere. In its current form, this PR increases
this tech debt.
I've tried to split off PRs and commits, but the main refactoring is
still a single monolith commit to make it compile and the tests pass.
## Demo
Adding
d1ae3b85d5/pyproject.json
as json schema (v7) to pycharm for `pyproject.toml`, you can try the IDE
support already:
[dove.webm](c293c272-c80b-459d-8c95-8c46a8d198a1)
In *some* places in our crates, `serde` (and `rkyv`) are optional
dependencies. I believe this was done out of reasons of "good sense,"
that is, it follows a Rust ecosystem pattern where serde integration
tends to be an opt-in crate feature. (And similarly for `rkyv`.)
However, ultimately, `uv` itself requires `serde` and `rkyv` to
function. Since our crates are strictly internal, there are limited
consumers for our crates without `serde` (and `rkyv`) enabled. I think
one possibility is that optional `serde` (and `rkyv`) integration means
that someone can do this:
cargo test -p pep440_rs
And this will run tests _without_ `serde` or `rkyv` enabled. That in
turn could lead to faster iteration time by reducing compile times. But,
I'm not sure this is worth supporting. The iterative compilation times
of
individual crates are probably fast enough in debug mode, even with
`serde` and `rkyv` enabled. Namely, `serde` and `rkyv` themselves
shouldn't need to be re-compiled in most cases. On `main`:
```
from-scratch: `cargo test -p pep440_rs --lib` 0.685
incremental: `cargo test -p pep440_rs --lib` 0.278s
from-scratch: `cargo test -p pep440_rs --features serde,rkyv --lib` 3.948s
incremental: `cargo test -p pep440_rs --features serde,rkyv --lib` 0.321s
```
So while a from-scratch build does take significantly longer, an
incremental build is about the same.
The benefit of doing this change is two-fold:
1. It brings out crates into alignment with "reality." In particular,
some crates were _implicitly_ relying on `serde` being enabled
without explicitly declaring it. This technically means that our
`Cargo.toml`s were wrong in some cases, but it is hard to observe it
because of feature unification in a Cargo workspace.
2. We no longer need to deal with the cognitive burden of writing
`#[cfg_attr(feature = "serde", ...)]` everywhere.
This PR principally adds a routine for converting a `Lock` to a
`Resolution`, where a `Resolution` is a map of package names pinned to
a specific version.
I'm not sure that a `Resolution` is ultimately what we want here (we
might need more stuff), but this was the quickest route I could find to
plug a `Lock` into our existing `uv pip install` infrastructure.
This commit also does a little refactoring of the `Lock` types. The
main thing is to permit extra state on some of the types (like a
`by_id` map on `Lock` for quick lookups of distributions) that aren't
included in the serialization format of a `Lock`. We achieve this
by defining separate `Wire` types that are automatically converted
to-and-from via `serde`.
Note that like with the lock file format types themselves, we leave a
few `todo!()` expressions around. The main idea is to get something
minimally working without spending too much effort here. (A fair bit
of refactoring will be required to generate a lock file, and it's
not clear how much this code will wind up needing to change anyway.)
In particular, we only handle the case of installing wheels from a
registry.
A demonstration of the full flow:
```
$ requirements.in
anyio
$ cargo run -p uv -- pip compile -p3.10 requirements.in --unstable-uv-lock-file
$ uv venv
$ cargo run -p uv -- pip install --unstable-uv-lock-file anyio -r requirements.in
Installed 5 packages in 7ms
+ anyio==4.3.0
+ exceptiongroup==1.2.1
+ idna==3.7
+ sniffio==1.3.1
+ typing-extensions==4.11.0
```
In order to install from a lock file, we start from the root and do a
breadth first traversal over its dependencies. We aren't yet filtering
on marker expressions (since they aren't in the lock file yet), but we
should be able to add that in the future. In so doing, the traversal
should select only the subset of distributions relevant for the current
platform.
This is meant to be a base on which to build. There are some parts
which are implicitly incomplete and others which are explicitly
incomplete. The latter are indicated by TODO comments.
Here is a non-exhaustive list of incomplete things. In many cases, these
are incomplete simply because the data isn't present in a
`ResolutionGraph`. Future work will need to refactor our resolver so
that this data is correctly passed down.
* Not all wheels are included. Only the "selected" wheel for the current
distribution is included.
* Marker expressions are always absent.
* We don't emit hashes for certainly kinds of distributions (direct
URLs, git, and path).
* We don't capture git information from a dependency specification.
Right now, we just always emit "default branch."
There are perhaps also other changes we might want to make to the format
of a more cosmetic nature. Right now, all arrays are encoded using
whatever the `toml` crate decides to do. But we might want to exert more
control over this. For example, by using inline tables or squashing more
things into strings (like I did for `Source` and `Hash`). I think the
main trade-off here is that table arrays are somewhat difficult to read
(especially without indentation), where as squashing things down into a
more condensed format potentially makes future compatible additions
harder.
I also went pretty light on the documentation here than what I would
normally do. That's primarily because I think this code is going to
go through some evolution and I didn't want to spend too much time
documenting something that is likely to change.
Finally, here's an example of the lock file format in TOML for the
`anyio` dependency. I generated it with the following command:
```
cargo run -p uv -- pip compile -p3.10 ~/astral/tmp/reqs/anyio.in --unstable-uv-lock-file
```
And that writes out a `uv.lock` file:
```toml
version = 1
[[distribution]]
name = "anyio"
version = "4.3.0"
source = "registry+https://pypi.org/simple"
[[distribution.wheel]]
url = "2f20c40b45/anyio-4.3.0-py3-none-any.whl"
hash = "sha256:048e05d0f6caeed70d731f3db756d35dcc1f35747c8c403364a8332c630441b8"
[[distribution.dependencies]]
name = "exceptiongroup"
version = "1.2.1"
source = "registry+https://pypi.org/simple"
[[distribution.dependencies]]
name = "idna"
version = "3.7"
source = "registry+https://pypi.org/simple"
[[distribution.dependencies]]
name = "sniffio"
version = "1.3.1"
source = "registry+https://pypi.org/simple"
[[distribution.dependencies]]
name = "typing-extensions"
version = "4.11.0"
source = "registry+https://pypi.org/simple"
[[distribution]]
name = "exceptiongroup"
version = "1.2.1"
source = "registry+https://pypi.org/simple"
[[distribution.wheel]]
url = "79fe92dd41/exceptiongroup-1.2.1-py3-none-any.whl"
hash = "sha256:5258b9ed329c5bbdd31a309f53cbfb0b155341807f6ff7606a1e801a891b29ad"
[[distribution]]
name = "idna"
version = "3.7"
source = "registry+https://pypi.org/simple"
[[distribution.wheel]]
url = "741d8c8280/idna-3.7-py3-none-any.whl"
hash = "sha256:82fee1fc78add43492d3a1898bfa6d8a904cc97d8427f683ed8e798d07761aa0"
[[distribution]]
name = "sniffio"
version = "1.3.1"
source = "registry+https://pypi.org/simple"
[[distribution.wheel]]
url = "75a9c94214/sniffio-1.3.1-py3-none-any.whl"
hash = "sha256:2f6da418d1f1e0fddd844478f41680e794e6051915791a034ff65e5f100525a2"
[[distribution]]
name = "typing-extensions"
version = "4.11.0"
source = "registry+https://pypi.org/simple"
[[distribution.wheel]]
url = "936e209267/typing_extensions-4.11.0-py3-none-any.whl"
hash = "sha256:c1f94d72897edaf4ce775bb7558d5b79d8126906a14ea5ed1635921406c0387a"
```
## Summary
This index strategy resolves every package to the latest possible
version across indexes. If a version is in multiple indexes, the first
available index is selected.
Implements #3137
This closely matches pip.
## Test Plan
Good question. I'm hesitant to use my certifi example here, since that
would inevitably break when torch removes this package. Please comment!
## Summary
Simplifies dependency errors of the form `you require package-a and you
require package-b` to `you require package-a and package-b`. Resolves
https://github.com/astral-sh/uv/issues/1009.
The only thing a `OnceMap` really needs to be able to do with the value
is to clone it. All extant uses benefited from having this done for them
by automatically wrapping values in an `Arc`. But this isn't necessarily
true for all things. For example, a value might have an `Arc` internally
to making cloning cheap in other contexts, and it doesn't make sense to
re-wrap it in an `Arc` just to use it with a `OnceMap`. Or
alternatively, cloning might just be cheap enough on its own that an
`Arc` isn't worth it.
## Summary
We now recursively expand any self-dependencies via extras, which lets
us detect conflicts sooner and avoid building unnecessary versions of
packages that are excluded via the extra.
Closes https://github.com/astral-sh/uv/issues/3135.
Previously, uv-auth would fail to compile due to a missing process
feature. I chose to make all tokio features we use top level features,
so we can share the tokio cache between all test invocations.
## Summary
See the diff in the tests. If you have a constraint with an extra, we
should respect it, but we shouldn't _add_ the extra to the requirements.
## Summary
I found some of these too bare (e.g., when they _just_ show a package
name with no other information). For me, this makes it easier to
differentiate error message copy from data. But open to other opinions.
Take a look at the fixture changes and LMK!
## Summary
This PR avoids: (1) using the lookahead resolver when `--no-deps` is
specified (we'll never use those requirements), and (2) including any
transitive requirements when searching for allowed URLs, etc., when
`--no-deps` is specified.
Closes https://github.com/astral-sh/uv/issues/3183.
## Summary
pip prefers somewhat-constrained over unconstrained packages... but only
if they're at equal depths in the tree. We don't have a way to track the
latter property yet (I've added a TODO), so for now, we should remove
this constraint -- it seems to be counter-productive.
I've filed https://github.com/astral-sh/uv/issues/3149 as a follow-up.
Closes https://github.com/astral-sh/uv/issues/3143
## Test Plan
- `git clone https://github.com/drivendataorg/zamba.git`
- `cat "-e .[tests]" > req.in`
- `cargo run venv && cargo run pip compile req.in --refresh -n
--python-platform linux --python-version 3.8`
## Summary
We weren't setting a priority for editables, so they were being visited
last.
I think there's still a problem whereby we're not aggressive enough in
visiting recursive extras (and, in fact, that's making it really hard to
write a test -- I wrote a test, but the most-reduced case still fails,
and I'd need to add a layer of indirection to make it
fail-on-main-but-pass-on-this-branch), but that problem likely already
existed on main prior to #3087, so I just want to get this quick fix out
now.
Closes https://github.com/astral-sh/uv/issues/3127.
## Test Plan
- `git clone https://github.com/cda-tum/mqt-core.git`
- `cargo run venv`
- `cargo run pip install 'scikit-build-core[pyproject]>=0.8.1'
'setuptools_scm>=7' 'pybind11>=2.12' --resolution=lowest-direct`
- `cargo run pip install --no-build-isolation
'-ve.[test,qiskit,evaluation,coverage]' --resolution=lowest-direct`
Given requirements like:
```
black==23.1.0
black[colorama]
```
The resolver will (on `main`) add a dependency on Black, and then try to
use the most recent version of Black to satisfy `black[colorama]`. For
sake of example, assume `black==24.0.0` is the most recent version. Once
the selects this most recent version, it'll fetch the metadata, then
return the dependencies for `black==24.0.0` with the `colorama` extra
enabled. Finally, it will tack on `black==24.0.0` (a dependency on the
base package). The resolver will then detect a conflict between
`black==23.1.0` and `black==24.0.0`, and throw out
`black[colorama]==24.0.0`, trying to next most-recent version.
This is both wasteful and can cause problems, since we're fetching
metadata for versions that will _never_ satisfy the resolver. In the
`apache-airflow[all]` case, I also ran into an issue whereby we were
attempting to build very old versions of `apache-airflow` due to
`apache-airflow[pandas]`, which in turn led to resolution failures.
The solution proposed here is that we create a new proxy package with
exactly two dependencies: one on `black` and one of `black[colorama]`.
Both of these packages must be at the same version as the proxy package,
so the resolver knows much _earlier_ that (in the above example) the
extra variant _must_ match `23.1.0`.
## Summary
resolves https://github.com/astral-sh/uv/issues/3106
## Test Plan
added a simple test where the password provided in `UV_INDEX_URL` is
hidden in the output as expected.
## Summary
This PR adds basic struct definitions along with a "workspace" concept
for discovering settings. (The "workspace" terminology is used to match
Ruff; I did not invent it.)
A few notes:
- We discover any `pyproject.toml` or `uv.toml` file in any parent
directory of the current working directory. (We could adjust this to
look at the directories of the input files.)
- We don't actually do anything with the configuration yet; but those
PRs are large and I want this to be reviewed in isolation.
