Add tests for the lsp integration

Ensure that autocompletion works fine for simple things

Author: Théophane Hufschmitt

Diff for: project.ncl

@@ -70,6 +70,27 @@ organist.OrganistExpression
           touch $out
         "%,
           },
+
+          lsp = {
+            name = "organist-lsp-integration",
+            version = "0.0",
+            env.buildInputs = {
+              nls = import_nix "nixpkgs#nls",
+              python3 = import_nix "nixpkgs#python3",
+              pygls = import_nix "nixpkgs#python3Packages.pygls",
+              pytest = import_nix "nixpkgs#python3Packages.pytest",
+              pytest-asyncio = import_nix "nixpkgs#python3Packages.pytest-asyncio",
+            },
+            env = {
+              src = import_nix "self",
+              phases = ["unpackPhase", "testPhase", "installPhase"],
+              testPhase = nix-s%"
+                  cd tests/lsp
+                  pytest | tee $out
+                "%,
+              installPhase = "touch $out",
+            },
+          },
         },
 
       flake.checks = import "tests/main.ncl",

Diff for: tests/lsp/.gitignore

@@ -0,0 +1 @@
+__pycache__

Diff for: tests/lsp/conftest.py

@@ -0,0 +1,21 @@
+import testlib
+import asyncio
+import pytest
+import pytest_asyncio
+from lsprotocol import types as lsp
+
+@pytest_asyncio.fixture
+async def client():
+    # Setup
+    client = testlib.LanguageClient("organist-test-suite", "v1")
+    await client.start_io("nls")
+    response = await client.initialize_async(
+            lsp.InitializeParams(
+                capabilities=lsp.ClientCapabilities(),
+                root_uri="."
+            )
+        )
+    assert response is not None
+    client.initialized(lsp.InitializedParams())
+    return client
+

Diff for: tests/lsp/template/nickel.lock.ncl

@@ -0,0 +1 @@
+{ organist = import "../../../lib/organist.ncl" }

Diff for: tests/lsp/test_completion.py

@@ -0,0 +1,109 @@
+import pytest
+import pytest_asyncio
+from lsprotocol import types as lsp
+from testlib import LanguageClient, open_file
+
+async def complete(client: LanguageClient, file_uri: str, pos: lsp.Position):
+    """
+    Trigger an autocompletion in the given file at the given position
+    """
+    results = await client.text_document_completion_async(
+        params=lsp.CompletionParams(
+            text_document=lsp.TextDocumentIdentifier(file_uri),
+            position=pos,
+        )
+    )
+    assert results is not None
+
+    if isinstance(results, lsp.CompletionList):
+        items = results.items
+    else:
+        items = results
+    return items
+
+@pytest.mark.asyncio
+async def test_completion_at_toplevel(client):
+    """
+    Test that getting an autocompletion at toplevel shows the available fields
+    """
+
+    test_file = 'template/project.ncl'
+    with open('../../templates/default/project.ncl') as template_file:
+        test_file_content = template_file.read()
+
+    test_uri = open_file(client, test_file, test_file_content)
+
+    completion_items = await complete(
+        client,
+        test_uri,
+        lsp.Position(line=12, character=0) # Empty line in the `config` record
+    )
+
+    labels = [item.label for item in completion_items]
+    assert "files" in labels
+    files_item = [item for item in completion_items if item.label == "files"][0]
+    assert files_item.documentation.value != ""
+
+@pytest.mark.asyncio
+async def test_completion_sub_field(client: LanguageClient):
+    """
+    Test that completing on an option shows the available sub-options
+    """
+    test_file = 'template/projectxx.ncl'
+    test_file_content = """
+let inputs = import "./nickel.lock.ncl" in
+let organist = inputs.organist in
+
+organist.OrganistExpression
+& {
+    Schema,
+    config | Schema = {
+      files.foo.c
+    },
+}
+| organist.modules.T
+    """
+    test_uri = open_file(client, test_file, test_file_content)
+    completion_items = await complete(
+        client,
+        test_uri,
+        lsp.Position(line=8, character=17) # The `c` in `files.foo.c`
+    )
+
+    labels = [item.label for item in completion_items]
+    assert "content" in labels
+    content_item = [item for item in completion_items if item.label == "content"][0]
+    assert content_item.documentation.value != ""
+
+@pytest.mark.asyncio
+async def test_completion_with_custom_module(client: LanguageClient):
+    """
+    Test that completing takes into account extra modules
+    """
+    test_file = 'template/projectxx.ncl'
+    test_file_content = """
+let inputs = import "./nickel.lock.ncl" in
+let organist = inputs.organist in
+
+organist.OrganistExpression & organist.tools.direnv
+& {
+    Schema,
+    config | Schema = {
+
+    },
+}
+| organist.modules.T
+    """
+    test_uri = open_file(client, test_file, test_file_content)
+    completion_items = await complete(
+        client,
+        test_uri,
+        lsp.Position(line=8, character=0) # Empty line in the `config` record
+    )
+
+    labels = [item.label for item in completion_items]
+    assert "direnv" in labels
+
+    ## No documentation for direnv yet
+    # content_item = [item for item in completion_items if item.label == "direnv"][0]
+    # assert content_item.documentation.value != ""

Diff for: tests/lsp/test_hover.py

@@ -0,0 +1,90 @@
+import pytest
+import pytest_asyncio
+from lsprotocol import types as lsp
+from testlib import LanguageClient, open_file
+from dataclasses import dataclass
+from typing import Callable, List
+
+async def hover(client: LanguageClient, file_uri: str, pos: lsp.Position):
+    """
+    Trigger a hover in the given file at the given position
+    """
+    results = await client.text_document_hover_async(
+        params=lsp.HoverParams(
+            text_document=lsp.TextDocumentIdentifier(file_uri),
+            position=pos,
+        )
+    )
+    return results
+
+@dataclass
+class HoverTest:
+    file: str
+    position: lsp.Position
+    checks: Callable[[lsp.Hover], List[bool]]
+
+
+@pytest.mark.asyncio
+async def test_hover_on_option(client: LanguageClient):
+    """
+    Test that hovering over an option shows the right thing™
+    """
+    test_file = 'template/projectxx.ncl'
+    test_file_content = """
+let inputs = import "./nickel.lock.ncl" in
+let organist = inputs.organist in
+
+organist.OrganistExpression & organist.tools.direnv
+& {
+    Schema,
+    config | Schema = {
+        files."foo.ncl".content = "1",
+
+        shells = organist.shells.Bash,
+    },
+}
+| organist.modules.T
+    """
+    test_uri = open_file(client, test_file, test_file_content)
+
+    tests = [
+        HoverTest(
+            file=test_uri,
+            position=lsp.Position(line=8, character=11), # `files`
+            checks= lambda hover_info: [
+                lsp.MarkedString_Type1(language='nickel', value='Files') in hover_info.contents,
+                # Test that the contents contain a plain string (the documentation), and that it's non empty
+                next(content for content in hover_info.contents if type(content) == type("")) != "",
+            ]
+        ),
+        HoverTest(
+            file=test_uri,
+            position=lsp.Position(line=8, character=28), # `content`
+            checks= lambda hover_info: [
+                lsp.MarkedString_Type1(language='nickel', value='nix.derivation.NullOr nix.derivation.NixString') in hover_info.contents,
+                # Test that the contents contain a plain string (the documentation), and that it's non empty
+                next(content for content in hover_info.contents if type(content) == type("")) != "",
+            ]
+        ),
+        HoverTest(
+            file=test_uri,
+            position=lsp.Position(line=10, character=11), # `shells( =)`
+            checks= lambda hover_info: [
+                lsp.MarkedString_Type1(language='nickel', value='OrganistShells') in hover_info.contents,
+                # Test that the contents contain a plain string (the documentation), and that it's non empty
+                next(content for content in hover_info.contents if type(content) == type("")) != "",
+            ]
+        ),
+    ]
+
+    for test in tests:
+        hover_info = await hover(
+            client,
+            test.file,
+            test.position,
+        )
+        print(hover_info.contents)
+        for check in test.checks(hover_info):
+            assert check
+
+

Diff for: tests/lsp/testlib.py

@@ -0,0 +1,33 @@
+from pygls.lsp.client import BaseLanguageClient
+from typing import Optional
+import os
+from lsprotocol import types as lsp
+
+class LanguageClient(BaseLanguageClient):
+    pass
+
+def open_file(client: LanguageClient, file_path: str, file_content: Optional[str] = None):
+    """
+    Open the given file in the LSP.
+
+    If `file_content` is non `None`, then it will be used as the content sent to the LSP.
+    Otherwise, the actual file content will be read from disk.
+    """
+    file_uri = f"file://{os.path.abspath(file_path)}"
+    actual_file_content = file_content
+    if file_content is None:
+        with open(file_path) as content:
+            actual_file_content = content.read()
+
+    client.text_document_did_open(
+        lsp.DidOpenTextDocumentParams(
+            text_document=lsp.TextDocumentItem(
+                uri=file_uri,
+                language_id="nickel",
+                version=1,
+                text=actual_file_content
+            )
+        )
+    )
+    return file_uri
+