Fix custom configuration provider regression

.github/workflows/job-compile-and-test.yml

@@ -97,6 +97,11 @@ jobs:
         run: yarn test --scenario=SingleRootProject
         working-directory: Extension
 
+      - name: Run SimpleCppProject tests (Windows)
+        if: ${{ inputs.platform == 'windows' }}
+        run: yarn test --scenario=SimpleCppProject
+        working-directory: Extension
+
       - name: Run E2E IntelliSense features tests (Windows)
         if: ${{ inputs.platform == 'windows' }}
         run: yarn test --scenario=MultirootDeadlockTest
@@ -117,6 +122,13 @@ jobs:
           run: yarn test --scenario=SingleRootProject
           working-directory: Extension
 
+      - name: Run SimpleCppProject tests (linux/macOS)
+        if: ${{ inputs.platform == 'mac' || inputs.platform == 'linux' }}
+        uses: coactions/setup-xvfb@b6b4fcfb9f5a895edadc3bc76318fae0ac17c8b3 # v1.0.1
+        with:
+          run: yarn test --scenario=SimpleCppProject
+          working-directory: Extension
+
       - name: Run E2E IntelliSense features tests (linux/macOS)
         if: ${{ inputs.platform == 'mac' || inputs.platform == 'linux' }}
         uses: coactions/setup-xvfb@b6b4fcfb9f5a895edadc3bc76318fae0ac17c8b3 # v1.0.1

Extension/src/LanguageServer/client.ts

@@ -2304,9 +2304,24 @@ export class DefaultClient implements Client {
 
         // Wrap the provider lookup in a single task, so we can apply a timeout to the entire duration.
         const provideConfigurationAsync: () => Thenable<SourceFileConfigurationItem[] | undefined> = async () => {
+            const supportedUris: vscode.Uri[] = [];
+            for (const uri of docUris) {
+                try {
+                    if (!await provider.canProvideConfiguration(uri, tokenSource.token)) {
+                        continue;
+                    }
+                } catch {
+                    console.warn("Caught exception from canProvideConfiguration");
+                }
+                supportedUris.push(uri);
+            }
+            if (supportedUris.length === 0) {
+                return [];
+            }
+
             let configs: util.Mutable<SourceFileConfigurationItem>[] = [];
             try {
-                configs = await provider.provideConfigurations(docUris, tokenSource.token);
+                configs = await provider.provideConfigurations(supportedUris, tokenSource.token);
             } catch {
                 console.warn("Caught exception from provideConfigurations");
             }

Extension/test/scenarios/SimpleCppProject/tests/languageServer.integration.test.ts

@@ -133,6 +133,8 @@ async function changeCppProperties(cppProperties: config.ConfigurationJson, _dis
 suite("extensibility tests v3", function(): void {
     let cpptools: apit.CppToolsTestApi;
     let lastResult: api.SourceFileConfigurationItem[];
+    let configurationProvidedBeforeCanProvide: boolean = false;
+    const supportedUris: Set<string> = new Set<string>();
     const defaultConfig: api.SourceFileConfiguration = {
         includePath: [ "${workspaceFolder}", "/v3/folder" ],
         defines: [ "${workspaceFolder}" ],
@@ -156,14 +158,19 @@ suite("extensibility tests v3", function(): void {
     const provider: api.CustomConfigurationProvider = {
         name: "cpptoolsTest-v3",
         extensionId: "ms-vscode.cpptools-test3",
-        canProvideConfiguration(_document: vscode.Uri): Thenable<boolean> {
+        canProvideConfiguration(document: vscode.Uri): Thenable<boolean> {
+            supportedUris.add(document.toString());
             return Promise.resolve(true);
         },
         provideConfigurations(uris: vscode.Uri[]): Thenable<api.SourceFileConfigurationItem[]> {
             const result: api.SourceFileConfigurationItem[] = [];
             uris.forEach(uri => {
+                const uriString: string = uri.toString();
+                if (!supportedUris.has(uriString)) {
+                    configurationProvidedBeforeCanProvide = true;
+                }
                 result.push({
-                    uri: uri.toString(),
+                    uri: uriString,
                     configuration: defaultConfig
                 });
             });
@@ -220,10 +227,15 @@ suite("extensibility tests v3", function(): void {
             disposables.push(testHook.IntelliSenseStatusChanged(result => {
                 result = result as apit.IntelliSenseStatus;
                 if (result.filename === "main3.cpp" && result.status === apit.Status.IntelliSenseReady) {
-                    const expected: api.SourceFileConfigurationItem[] = [ {uri: uri.toString(), configuration: defaultConfig} ];
-                    assert.deepEqual(lastResult, expected);
-                    assert.deepEqual(lastBrowseResult, defaultFolderBrowseConfig);
-                    resolve();
+                    try {
+                        const expected: api.SourceFileConfigurationItem[] = [ {uri: uri.toString(), configuration: defaultConfig} ];
+                        assert.strictEqual(configurationProvidedBeforeCanProvide, false);
+                        assert.deepEqual(lastResult, expected);
+                        assert.deepEqual(lastBrowseResult, defaultFolderBrowseConfig);
+                        resolve();
+                    } catch (error) {
+                        reject(error);
+                    }
                 }
             }));
             setTimeout(() => { reject(new Error("timeout")); }, testHelpers.defaultTimeout);