optics-framework-lsp
A language server and linter for optics-framework test suites.
An optics suite is CSV files referring to each other by name, and nothing checks that those names line up. This does, across the whole project, over LSP while you type or as one command. Its rules come from optics-framework's own readers, so it agrees with the runtime.
Install
uv tool install optics-framework-lsp
Or from a checkout, for development:
uv sync
In an editor
Two packaged clients bundle the server's dependencies, so neither needs the steps above:
- VS Code —
editors/code - IntelliJ, PyCharm and other JetBrains IDEs —
editors/intellij
Both need a Python 3.12+ interpreter and attach to every *.csv in the project without claiming
the .csv extension, so whatever CSV editor you already use is untouched.
The linter
optics-lsp lint reports every problem in a suite in one shot. Point it at a project:
$ optics-lsp lint ~/projects/my_project
Line numbers are 1-based, matching your editor's status bar. A whole project takes about 60 ms including process start, because nothing on this path imports any LSP machinery.
The exit code is 0 whenever validation ran, findings or not. Non-zero means the input could
not be read at all. Which severities should block a pipeline is your policy, so read status
if you want that decision made for you.
JSON, for another program
Add --json for the machine-readable form. A caller holding uploaded files in memory, with
nothing on disk, can pipe them in instead and skip the filesystem entirely:
$ echo '{"files": [{"name": "modules.csv", "content": "module_name,module_step\nM,Sleep\n"}]}' \
| optics-lsp lint
Reading on stdin always answers JSON:
{
"status": "FAIL",
"analyzed": { "modules.csv": "modules" },
"skipped": [],
"diagnostics": [
{
"uri": "modules.csv",
"severity": "error",
"code": "keyword-arity",
"message": "'Sleep' takes 1-1 params, got 0",
"row": 2,
"range": { "startLine": 1, "startColumn": 0, "endLine": 2, "endColumn": 0 },
"source": "optics"
}
]
}
row is 1-based for a person, range is 0-based for an editor. Diagnostics arrive sorted by
file then row, so a caller need not re-sort.
Shelling out from Node: pass the arguments as an array with the payload on stdin rather than
interpolating either into a shell string, and raise maxBuffer past its 1 MB default.
analyzed and skipped: which files were even looked at
File kind comes from the header row, not the filename. analyzed says what each file became
(test_cases, modules, elements, error_definitions); skipped lists the CSVs whose
header matched none of those.
optics ignores those files too, so a skipped file is usually a dataset and fine. But a
test_cases file with a typo in its header lands there as well, and would otherwise be
indistinguishable from a clean one.
What it reports
Two severities, and the line between them is one question: does optics fail, or does it run and do something you probably didn't mean?
Errors are a name that resolves to nothing, or a call the keyword rejects:
| code | meaning |
|---|---|
module-not-found |
a test step names a module no file defines |
keyword-not-found |
a module step is neither a keyword nor another module |
keyword-arity |
a keyword got too few or too many params |
element-not-found |
a ${ref} has no element and nothing binds it |
Warnings mean it loads, but a row you wrote isn't doing what it looks like:
| code | meaning |
|---|---|
duplicate-module, duplicate-test-case |
the later definition wins, wherever the files sit |
duplicate-element |
a file repeats an entire element row |
duplicate-error-code, duplicate-match-string |
error definitions merge across files, so these clash |
error-definition-incomplete |
a row missing a column, so it never matches |
csv-too-few-columns |
the reader skips the row |
csv-too-many-columns |
the extra cells are dropped |
csv-whitespace-line |
a row of nothing but separators |
The language server
Run with no arguments and it speaks LSP over stdio. Unknown flags are ignored rather than
rejected, so a client that insists on passing --stdio needs no special handling.
One workspace folder is one project. Cross-file rules mean a single edit can change
diagnostics anywhere in the suite, so the whole folder is revalidated on every change, and the
server asks the client to watch **/*.csv so a git checkout is picked up too. Open buffers
override what is on disk. Dot folders are never descended into, because a project's .venv holds
optics-framework's own sample CSVs and images, which would invent element and module names the
project does not have.
Features
Diagnostics
Everything from the linter section above, live, across the whole project. Because resolution
is a project-wide question, defining an element in one file clears the element-not-found in
another without touching it.
Completion
Aware of which column you are in, because in a CSV the column is the context.
| where the cursor is | what is offered |
|---|---|
| an empty file | the four header rows, since the header decides the file's kind |
module_step |
every keyword and every module in the project, since a step can be either |
| a param cell | what that particular keyword accepts at that position |
test_step, module_name |
modules that already exist, since both columns continue a block |
element_name |
names used somewhere but never defined |
any element_id* |
template image filenames found anywhere in the project |
test_case |
existing test cases, plus the lifecycle names (Suite Setup, …) not yet used |
Param completion is specific rather than generic. Read Data's second param offers the
project's data files; Invoke API's first offers collection.api identifiers parsed out of
the project's YAML; Run Loop and Execute Module offer modules, written bare. Params with a
documented set of values offer exactly those. direction gives up, down, left, right;
rule gives any, all; element_state gives visible, invisible, enabled, disabled.
Condition alternates condition and target, so it offers modules in the target slots and
modules-or-variables in the others, with ! inversion preserved.
Accepting a param the header does not yet cover widens the header in the same edit, because
csv.DictReader drops cells the header does not name and the param would otherwise silently
vanish.
Hover
A keyword's real signature and the framework's own docstring, which is where the accepted values are actually written:
Press Element(element, repeat='1', offset_x='0', offset_y='0', index='0',
aoi_x='0', aoi_y='0', aoi_width='100', aoi_height='100', event_name=None)
Press a specified element.
:param element: The element to be pressed (text, xpath or image).
:param repeat: Number of times to repeat the press.
:param index: Index of the element if multiple matches are found.
:param aoi_width: Width percentage of Area of Interest (0-100). Default: 100.
Defaults are rendered as name='value', so what an omitted cell falls back to is visible
without reading the source.
Signature help
The keyword's params with the column you are in marked active, retriggering on every comma, which is how you tell param 4 from param 5 in a row of commas.
Goto definition
From a step to the module it runs, or from a ${ref} to the elements it reads. Every ${name}
in the cell is offered, not just one: a fallback element is several rows, and so is
${a} == ${b}.
Two details it gets right. A module_step naming something that is also a keyword resolves
to the keyword, so a same-named module is not offered, mirroring what the runner does. And
Condition's !Name inversion is stripped the same way the runner strips it.
Find references
Every place a name is used across the project, optionally including where it is bound. Works on test cases, modules, elements and error codes, the things the project owns. A keyword belongs to the framework, and an image, data file or API identifier names something outside the CSVs, so neither comes back from here.
Rename
Renames across every file that writes the name, with prepare-rename so the client can reject an invalid position before you start typing. This is the feature that most needs to be project-wide: the runner keys everything by name, so a rename that misses one cell quietly changes what runs instead of failing loudly.
Document symbols
One file's outline: what it defines, and the rows making each one up:
Open App [Function] 2 steps
Launch App [Method]
Sleep [Method] 2
Login [Function] 1 step
Press Element [Method] ${btn}
Workspace symbols
Every name the project declares, searchable from anywhere — "Go to Symbol in Workspace" in
VS Code, workspace/symbol on the wire. Declarations only: a module's steps and an element's
locators belong to the file outline, and repeating them here would bury the handful of names
being searched for under every row that mentions them.
| kind | what it is |
|---|---|
Class |
a test case |
Function |
a module |
Variable |
an element, once, however many locator rows it has |
Constant |
an error code |
The match is a case-insensitive substring, and each result carries the kind its file's header
row made it (modules, test_cases, …) as the container, since that is the only thing telling
a module from a test case of the same name.
Semantic tokens
Highlighting a CSV grammar cannot express, because the meaning of a cell depends on the column above it and on the rest of the project:
| token | what it marks |
|---|---|
keyword |
the header row, the names that decide what the file is |
class |
a test case |
function |
a module, wherever it is named |
method |
a step that resolves to a framework keyword |
variable |
${name}, and an element_name that defines one |
string |
a locator, a data file, an API identifier |
enumMember |
an error code, and a param with a documented set of values |
operator |
the ! that inverts a Condition |
A framework keyword also carries the defaultLibrary modifier, so themes colour it apart from
a module of the same shape, which they would otherwise draw identically.
The keyword catalog
src/optics_framework_lsp/keywords.py is generated and holds 49 keywords from
optics-framework 1.9.3: each one's params, which are required, the defaults, and the
framework's own docstring, which is where hover text and the param values come from.
It is compiled in rather than read from your environment. Importing optics_framework.api.*
pulls numpy, cv2, pandas and skimage through common.optics_builder, needing a 342 MB install
and failing outright if any one of those is broken, leaving a project with no keyword
diagnostics at all and no explanation why.
To refresh it for a new optics release:
python scripts/update_catalog.py ~/src/optics-framework
python scripts/update_catalog.py --check # exits 1 if the committed table is stale
Signatures are read with ast, never imported, which is what lets the script run against a
bare checkout or a --no-deps install and makes it usable for diffing two releases. It refuses
to run if one of the four API classes gains a base class, since that would mean keywords it
cannot see. A test runs --check, so a stale table fails the suite.
Development
uv run pytest tests/ -q
One test needs optics-framework itself and skips without it; point OPTICS_PROBE_VENV at a
virtualenv that has it to run that one.
The engine is deliberately protocol-free. validate() returns plain Finding objects and each
transport converts at its own boundary: server.py to lsprotocol diagnostics, lint.py to
JSON. import lsprotocol.types alone costs ~290 ms, which a long-lived server pays once and a
per-call command would pay every time. tests/test_lint.py asserts the lint path imports
neither pygls nor lsprotocol, so it stays that way.
License
Apache 2.0.
Release files for optics-framework-lsp 1.1.0
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| optics_framework_lsp-1.1.0.tar.gz | 40.5 kB | Details |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| optics_framework_lsp-1.1.0-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 88.6 kB
Release files / optics_framework_lsp-1.1.0.tar.gz
| Download URL | optics_framework_lsp-1.1.0.tar.gz |
|---|---|
| Size | 40.5 kB |
| Tags | Source |
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| Uploaded via |
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