Initial Black format check feature

bundled/tool/lsp_server.py

@@ -255,6 +255,56 @@ def _get_args_by_file_extension(document: workspace.Document) -> List[str]:
 # **********************************************************
 
 
+# **********************************************************
+# Check file features ends here
+# **********************************************************
+
+
+@LSP_SERVER.feature(
+    lsp.TEXT_DOCUMENT_DIAGNOSTIC,
+    lsp.DiagnosticRegistrationOptions(
+        inter_file_dependencies=False,
+        workspace_diagnostics=False,
+    ),
+)
+def diagnostics(params: lsp.DocumentDiagnosticParams) -> lsp.DocumentDiagnosticReport:
+    """LSP handler for textDocument/diagnostic request."""
+    document = LSP_SERVER.workspace.get_text_document(params.text_document.uri)
+    settings = _get_settings_by_document(document)
+    diagnostics = []
+    if settings.get("check", False):
+        diagnostics = _check_document(document)
+    return lsp.RelatedFullDocumentDiagnosticReport(items=diagnostics)
+
+
+def _check_document(document: workspace.Document) -> lsp.DocumentDiagnosticReport:
+    """Runs black in check mode to get diagnostics."""
+    extra_args = ["--check"] + _get_args_by_file_extension(document)
+    extra_args += [ "--stdin-filename", _get_filename_for_black(document)]
+    result = _run_tool_on_document(document, use_stdin=True, extra_args=extra_args)
+    diagnostics = []
+    if result and result.stderr and "would reformat" in result.stderr:
+        log_to_output(result.stderr)
+        diagnostics = [
+            lsp.Diagnostic(
+                range=lsp.Range(
+                    start=lsp.Position(line=0, character=0),
+                    end=lsp.Position(line=0, character=0),
+                ),
+                message=f"Black would reformat this file.",
+                severity=lsp.DiagnosticSeverity.Warning,
+                source=TOOL_DISPLAY,
+                code="black",
+            )
+        ]
+    return diagnostics
+
+
+# **********************************************************
+# Check file features ends here
+# **********************************************************
+
+
 # **********************************************************
 # Required Language Server Initialization and Exit handlers.
 # **********************************************************
@@ -350,6 +400,7 @@ def _update_workspace_settings_with_version_info(
 # *****************************************************
 def _get_global_defaults():
     return {
+        "check": False,
         "path": GLOBAL_SETTINGS.get("path", []),
         "interpreter": GLOBAL_SETTINGS.get("interpreter", [sys.executable]),
         "args": GLOBAL_SETTINGS.get("args", []),

package.json

@@ -87,6 +87,15 @@
                     "scope": "resource",
                     "type": "array"
                 },
+                "black-formatter.check": {
+                    "default": false,
+                    "markdownDescription": "%settings.check.description%",
+                    "scope": "resource",
+                    "type": "boolean",
+                    "tags": [
+                        "experimental"
+                    ]
+                },
                 "black-formatter.cwd": {
                     "default": "${workspaceFolder}",
                     "markdownDescription": "%settings.cwd.description%",

package.nls.json

@@ -2,6 +2,7 @@
     "extension.description": "Formatting support for Python files using the Black formatter.",
     "command.restartServer": "Restart Server",
     "settings.args.description": "Arguments passed to Black to format Python files. Each argument should be provided as a separate string in the array. \n Example: \n `\"black-formatter.args\" = [\"--config\", \"<file>\"]`",
+    "settings.check.description": "When enabled, the extension will run `black` with `--check` on open, save or changes.",
     "settings.cwd.description": "Sets the current working directory used to format Python files with Black. By default, it uses the root directory of the workspace `${workspaceFolder}`. You can set it to `${fileDirname}` to use the parent folder of the file being formatted as the working directory for Black.",
     "settings.path.description": "Path or command to be used by the extension to format Python files with Black. Accepts an array of a single or multiple strings. If passing a command, each argument should be provided as a separate string in the array. If set to `[\"black\"]`, it will use the version of Black available in the `PATH` environment variable. Note: Using this option may slowdown formatting. \n  Examples: \n  - `[\"~/global_env/black\"]` \n  - `[\"conda\", \"run\", \"-n\", \"lint_env\", \"python\", \"-m\", \"black\"]`",
     "settings.importStrategy.description": "Defines which Black formatter binary to be used to format Python files. When set to `useBundled`, the extension will use the Black formatter binary that is shipped with the extension. When set to `fromEnvironment`, the extension will attempt to use the Black formatter binary and all dependencies that are available in the currently selected environment. **Note**: If the extension can't find a valid Black formatter binary in the selected environment, it will fallback to using the binary that is shipped with the extension. The `black-formatter.path` setting takes precedence and overrides the behavior of `black-formatter.importStrategy`.",

src/common/settings.ts

@@ -11,6 +11,7 @@ import { trace } from 'console';
 
 export interface ISettings {
     cwd: string;
+    check: boolean;
     workspace: string;
     args: string[];
     path: string[];
@@ -128,6 +129,7 @@ export async function getWorkspaceSettings(
 
     const workspaceSetting = {
         cwd: getCwd(config, workspace),
+        check: config.get<boolean>('check', false),
         workspace: workspace.uri.toString(),
         args: resolveVariables(config.get<string[]>('args', []), 'args', workspace),
         path: resolveVariables(config.get<string[]>('path', []), 'path', workspace, interpreter),
@@ -159,6 +161,7 @@ export async function getGlobalSettings(namespace: string, includeInterpreter?:
 
     const setting = {
         cwd: process.cwd(),
+        check: config.get<boolean>('check', false),
         workspace: process.cwd(),
         args: getGlobalValue<string[]>(config, 'args') ?? [],
         path: getGlobalValue<string[]>(config, 'path') ?? [],