error on unknown config options

packages/pyright-internal/src/common/configOptions.ts

@@ -1222,6 +1222,20 @@ export class ConfigOptions {
         const console = serviceProvider.tryGet(ServiceKeys.console) ?? new NullConsole();
         const errors = [];
 
+        // keep track of which options have been parsed so we can raise an error on unknown options later
+        // this is pretty cringe and we should just replace all this with some sort of schema validator thingy
+        // https://github.com/DetachHead/basedpyright/issues/64
+        const readOptions: (string | symbol)[] = [];
+        configObj = new Proxy(configObj, {
+            get: (target, name) => {
+                const result = target[name];
+                if (!readOptions.includes(name)) {
+                    readOptions.push(name);
+                }
+                return result;
+            },
+        });
+
         // Read the entries that should be an array of relative file paths
         for (const key of ['include', 'exclude', 'ignore', 'strict'] as const) {
             const configValue = configObj[key];
@@ -1479,6 +1493,11 @@ export class ConfigOptions {
                 }
             }
         }
+        for (const key of Object.keys(configObj)) {
+            if (!readOptions.includes(key)) {
+                errors.push(`unknown config option: ${key}`);
+            }
+        }
         return errors;
     }
 

packages/pyright-internal/src/tests/config.test.ts

@@ -24,6 +24,7 @@ import { TestFileSystem } from './harness/vfs/filesystem';
 import { cloneDeep } from 'lodash';
 import { deserialize, serialize } from '../backgroundThreadBase';
 import { AnalysisResults } from '../analyzer/analysis';
+import { existsSync } from 'fs';
 
 function createAnalyzer(console?: ConsoleInterface) {
     const cons = console ?? new NullConsole();
@@ -305,6 +306,7 @@ const setupPyprojectToml = (
     projectPath: string
 ): { configOptions: ConfigOptions; analysisResult: AnalysisResults | undefined } => {
     const cwd = normalizePath(combinePaths(process.cwd(), projectPath));
+    assert(existsSync(cwd));
     const service = createAnalyzer();
     let analysisResult = undefined as AnalysisResults | undefined;
     service.setCompletionCallback((result) => (analysisResult = result));
@@ -343,15 +345,24 @@ test('both pyright and basedpyright in pyproject.toml', () => {
     assert(!analysisResult.fatalErrorOccurred);
 });
 
-test('invalid setting in pyproject.toml', () => {
+test('invalid option value in pyproject.toml', () => {
     const { configOptions, analysisResult } = setupPyprojectToml(
-        'src/tests/samples/project_with_invalid_setting_in_pyproject_toml'
+        'src/tests/samples/project_with_invalid_option_value_in_pyproject_toml'
     );
     assert.strictEqual(configOptions.typeCheckingMode, undefined);
     assert(analysisResult?.configParseErrorOccurred);
     assert(!analysisResult.fatalErrorOccurred);
 });
 
+test('unknown option name in pyproject.toml', () => {
+    const { configOptions, analysisResult } = setupPyprojectToml(
+        'src/tests/samples/project_with_invalid_option_name_in_pyproject_toml'
+    );
+    assert(!('asdf' in configOptions));
+    assert(analysisResult?.configParseErrorOccurred);
+    assert(!analysisResult.fatalErrorOccurred);
+});
+
 test('FindFilesInMemoryOnly', () => {
     const cwd = normalizePath(process.cwd());
     const service = createAnalyzer();

packages/pyright-internal/src/tests/samples/project_with_invalid_option_name_in_pyproject_toml/pyproject.toml

@@ -0,0 +1,3 @@
+[tool.basedpyright]
+typeCheckingMode = "strict"
+asdf = "asdf"