This PR contains the scaffolding for a new control flow graph
implementation, along with its application to the `unreachable` rule. At
the moment, the implementation is a maximal over-approximation: no
control flow is modeled and all statements are counted as reachable.
With each additional statement type we support, this approximation will
improve.
So this PR just contains:
- A `ControlFlowGraph` struct and builder
- Support for printing the flow graph as a Mermaid graph
- Snapshot tests for the actual graphs
- (a very bad!) reimplementation of `unreachable` using the new structs
- Snapshot tests for `unreachable`
# Instructions for Viewing Mermaid snapshots
Unfortunately I don't know how to convince GitHub to render the Mermaid
graphs in the snapshots. However, you can view these locally in VSCode
if you install an extension that supports Mermaid graphs in Markdown,
and then add this to your `settings.json`:
```json
"files.associations": {
"*.md.snap": "markdown",
}
```
## Summary
This PR makes the `ruff_db` a required crate for `ruff_python_semantic`.
Refer
2623330715
## Test Plan
1. `maturin sdist --out dist`
2. `tar -xf dist/ruff-0.4.8.tar.gz --directory=dist/ruff-0.4.8`
3. `pip install dist/ruff-0.4.8.tar.gz` works
## Summary
When you try to remove an internal representation leaking into another
type and end up rewriting a simple version of `smallvec`.
The goal of this PR is to replace the `Box<[&'a str]>` with
`Box<QualifiedName>` to avoid that the internal `QualifiedName`
representation leaks (and it gives us a nicer API too). However, doing
this when `QualifiedName` uses `SmallVec` internally gives us all sort
of funny lifetime errors. I was lost but @BurntSushi came to rescue me.
He figured out that `smallvec` has a variance problem which is already
tracked in https://github.com/servo/rust-smallvec/issues/146
To fix the variants problem, I could use the smallvec-2-alpha-4 or
implement our own smallvec. I went with implementing our own small vec
for this specific problem. It obviously isn't as sophisticated as
smallvec (only uses safe code), e.g. it doesn't perform any size
optimizations, but it does its job.
Other changes:
* Removed `Imported::qualified_name` (the version that returns a
`String`). This can be replaced by calling `ToString` on the qualified
name.
* Renamed `Imported::call_path` to `qualified_name` and changed its
return type to `&QualifiedName`.
* Renamed `QualifiedName::imported` to `user_defined` which is the more
common term when talking about builtins vs the rest/user defined
functions.
## Test plan
`cargo test`
Update to [Rust
1.74](https://blog.rust-lang.org/2023/11/16/Rust-1.74.0.html) and use
the new clippy lints table.
The update itself introduced a new clippy lint about superfluous hashes
in raw strings, which got removed.
I moved our lint config from `rustflags` to the newly stabilized
[workspace.lints](https://doc.rust-lang.org/stable/cargo/reference/workspaces.html#the-lints-table).
One consequence is that we have to `unsafe_code = "warn"` instead of
"forbid" because the latter now actually bans unsafe code:
```
error[E0453]: allow(unsafe_code) incompatible with previous forbid
--> crates/ruff_source_file/src/newlines.rs:62:17
|
62 | #[allow(unsafe_code)]
| ^^^^^^^^^^^ overruled by previous forbid
|
= note: `forbid` lint level was set on command line
```
---------
Co-authored-by: Charlie Marsh <charlie.r.marsh@gmail.com>
## Summary
This is a follow-up to #7469 that attempts to achieve similar gains, but
without introducing malachite. Instead, this PR removes the `BigInt`
type altogether, instead opting for a simple enum that allows us to
store small integers directly and only allocate for values greater than
`i64`:
```rust
/// A Python integer literal. Represents both small (fits in an `i64`) and large integers.
#[derive(Clone, PartialEq, Eq, Hash)]
pub struct Int(Number);
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub enum Number {
/// A "small" number that can be represented as an `i64`.
Small(i64),
/// A "large" number that cannot be represented as an `i64`.
Big(Box<str>),
}
impl std::fmt::Display for Number {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self {
Number::Small(value) => write!(f, "{value}"),
Number::Big(value) => write!(f, "{value}"),
}
}
}
```
We typically don't care about numbers greater than `isize` -- our only
uses are comparisons against small constants (like `1`, `2`, `3`, etc.),
so there's no real loss of information, except in one or two rules where
we're now a little more conservative (with the worst-case being that we
don't flag, e.g., an `itertools.pairwise` that uses an extremely large
value for the slice start constant). For simplicity, a few diagnostics
now show a dedicated message when they see integers that are out of the
supported range (e.g., `outdated-version-block`).
An additional benefit here is that we get to remove a few dependencies,
especially `num-bigint`.
## Test Plan
`cargo test`
## Summary
Fixes some TODOs introduced in
https://github.com/astral-sh/ruff/pull/6538. In short, given an
expression like `1 if x > 0 else "Hello, world!"`, we now return a union
type that says the expression can resolve to either an `int` or a `str`.
The system remains very limited, it only works for obvious primitive
types, and there's no attempt to do inference on any more complex
variables. (If any expression yields `Unknown` or `TypeError`, we
propagate that result throughout and abort on the client's end.)
