liar
Finds Python code that says one thing and does another.
'save_user' is never awaited. this line does nothing.
An async function called without await builds a coroutine and throws it
away. The body never runs, nothing raises, and the endpoint cheerfully returns
success. liar underlines it the moment you save, and offers to add the await.
What it finds
|
|
| C1 |
An async function called without await |
| C2 |
A blocking call inside async code, directly or through a sync helper |
| C3a |
A name that asks a question whose answer is not a boolean |
| C3b |
A name that promises a number and holds something else |
| C3e |
A name that says nothing, over a scope long enough to matter |
| C3f |
One name meaning several unrelated things |
| C4 |
A resource not released on every path out, including when something raises |
| C5 |
A docstring the code disagrees with |
It is built to stay quiet when it is unsure. An unresolvable name, an
unrecognised decorator, or a value whose type cannot be known all produce
nothing. It will miss some real bugs as a result, and it will rarely waste your
time.
Requirements
The extension starts the liar-lsp language server, which does the analysis.
Install it with a recent stable Rust:
cargo install --git https://github.com/Momo4811/liar liar-lsp
If it is not on your PATH, point liar.path at it.
Features
Findings on save, for the whole project, so changing helpers.py updates
the findings in the files that import it.
Add await, a quick fix for C1, offered only inside async def. Adding
await inside a plain def would be a syntax error.
Three tones for the same finding:
professional coroutine 'save_user' is called but never awaited
dry 'save_user' is never awaited. this line does nothing.
brutal you wrote 'save_user()' and then threw it away.
Settings
| Setting |
Default |
|
liar.enable |
true |
Run liar on Python files |
liar.tone |
dry |
professional, dry or brutal |
liar.path |
|
Path to liar-lsp. Empty means look on PATH |
Project configuration
A liar.toml at the workspace root is read by both the editor and the
liar command line, so the two always agree:
ignore = ["C3e"] # turn a check off
exclude = ["generated/**"] # skip files
scope-threshold = 60 # C3e: lines of scope before a name must say something
Changes apply as soon as the file is saved. Virtual environments,
node_modules and __pycache__ are never analysed.
More
The checks, how they were tested against 1,305 files of real code, and every
false positive found along the way are in the
repository.
