fix: duplicate project roots in multi-root workspaces

.github/workflows/e2eUI.yml

@@ -162,16 +162,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Setup Build Environment (Xvfb)
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y libxkbfile-dev pkg-config libsecret-1-dev libxss1 dbus xvfb libgtk-3-0 libgbm1
-          # Use 1920x1080 so the Java Projects view (rendered inside the Explorer
-          # sidebar) gets enough vertical space. With 1024x768 the sticky
-          # pane-header overlapped tree rows and intercepted click events.
-          sudo /usr/bin/Xvfb :99 -screen 0 1920x1080x24 > /dev/null 2>&1 &
-          sleep 3
-
       - name: Set up JDK 21
         uses: actions/setup-java@v4
         with:
@@ -181,7 +171,7 @@ jobs:
       - name: Setup Node.js environment
         uses: actions/setup-node@v4
         with:
-          node-version: 20
+          node-version: 22
 
       - name: Setup autotest
         run: npm install -g @vscjava/vscode-autotest
@@ -199,7 +189,9 @@ jobs:
           AZURE_OPENAI_API_KEY: ${{ secrets.AZURE_OPENAI_API_KEY }}
           AZURE_OPENAI_DEPLOYMENT: ${{ secrets.AZURE_OPENAI_DEPLOYMENT }}
         run: |
-          DISPLAY=:99 autotest run "test/e2e-plans/${{ matrix.plan }}.yaml" \
+          # Use 1920x1080 so the Java Projects view gets enough vertical space.
+          xvfb-run -a -s "-screen 0 1920x1080x24" \
+            autotest run "test/e2e-plans/${{ matrix.plan }}.yaml" \
             --vsix "$(pwd)/vscode-java-dependency.vsix" \
             --output "test-results/${{ matrix.plan }}"
 
@@ -234,7 +226,7 @@ jobs:
       - name: Setup Node.js environment
         uses: actions/setup-node@v4
         with:
-          node-version: 20
+          node-version: 22
 
       - name: Setup autotest
         run: npm install -g @vscjava/vscode-autotest
@@ -272,7 +264,7 @@ jobs:
       - name: Setup Node.js environment
         uses: actions/setup-node@v4
         with:
-          node-version: 20
+          node-version: 22
 
       - name: Setup autotest
         run: npm install -g @vscjava/vscode-autotest

src/languageServerApi/languageServerApiManager.ts

@@ -116,12 +116,16 @@ class LanguageServerApiManager {
                     // Server is sending project data, so it's definitely running.
                     // Mark as running so ready() returns immediately on subsequent calls.
                     this.isServerRunning = true;
-                    // During import, the JDTLS server is blocked by Eclipse workspace
-                    // operations and cannot respond to queries. Instead of triggering
-                    // a refresh (which queries the server), directly add projects to
-                    // the tree view from the notification data.
-                    const projectUris = uris.map(u => u.toString());
-                    commands.executeCommand(Commands.VIEW_PACKAGE_INTERNAL_ADD_PROJECTS, projectUris);
+                    if (this.isServerReady) {
+                        commands.executeCommand(Commands.VIEW_PACKAGE_INTERNAL_REFRESH, /* debounce = */true);
+                    } else {
+                        // During import, the JDTLS server is blocked by Eclipse workspace
+                        // operations and cannot respond to queries. Instead of triggering
+                        // a refresh (which queries the server), directly add projects to
+                        // the tree view from the notification data.
+                        const projectUris = uris.map(u => u.toString());
+                        commands.executeCommand(Commands.VIEW_PACKAGE_INTERNAL_ADD_PROJECTS, projectUris);
+                    }
                     syncHandler.updateFileWatcher(Settings.autoRefresh());
                 }));
             }

src/views/dependencyDataProvider.ts

@@ -2,6 +2,7 @@
 // Licensed under the MIT license.
 
 import * as _ from "lodash";
+import * as path from "path";
 import {
     commands, Event, EventEmitter, ExtensionContext, ProviderResult,
     RelativePattern, TreeDataProvider, TreeItem, Uri, window, workspace,
@@ -226,7 +227,10 @@ export class DependencyDataProvider implements TreeDataProvider<ExplorerNode> {
      */
     public addProgressiveProjects(projectUris: string[]): void {
         const folders = workspace.workspaceFolders;
-        if (!folders || !folders.length) {
+        // Multi-root workspaces use WorkspaceNode roots. Those roots can remain
+        // cached briefly after switching to a single folder, so wait for the
+        // full refresh rather than creating a mixed root structure.
+        if (!folders || folders.length !== 1 || this._rootItems?.some(root => root instanceof WorkspaceNode)) {
             return;
         }
 
@@ -238,11 +242,14 @@ export class DependencyDataProvider implements TreeDataProvider<ExplorerNode> {
             this._rootItems
                 .filter((n): n is ProjectNode => n instanceof ProjectNode)
                 .map((n) => n.uri)
+                .filter((uri): uri is string => Boolean(uri))
+                .map(getProjectUriKey)
         );
 
         let added = false;
         for (const uriStr of projectUris) {
-            if (existingUris.has(uriStr)) {
+            const uriKey = getProjectUriKey(uriStr);
+            if (existingUris.has(uriKey)) {
                 continue;
             }
             // Extract project name from URI (last non-empty path segment)
@@ -253,7 +260,7 @@ export class DependencyDataProvider implements TreeDataProvider<ExplorerNode> {
                 kind: NodeKind.Project,
             };
             this._rootItems.push(new ProjectNode(nodeData, undefined));
-            existingUris.add(uriStr);
+            existingUris.add(uriKey);
             added = true;
         }
 
@@ -308,3 +315,16 @@ export class DependencyDataProvider implements TreeDataProvider<ExplorerNode> {
         }
     }
 }
+
+function getProjectUriKey(uriString: string): string {
+    const uri = Uri.parse(uriString);
+    if (uri.scheme !== "file") {
+        return uri.toString();
+    }
+
+    let fsPath = path.normalize(uri.fsPath);
+    if (fsPath !== path.parse(fsPath).root) {
+        fsPath = fsPath.replace(/[\\\/]+$/, "");
+    }
+    return process.platform === "win32" ? fsPath.toLowerCase() : fsPath;
+}

test/e2e-plans/java-dep-project-explorer.yaml

@@ -152,3 +152,79 @@ steps:
       name: "App"
       exact: true
     timeout: 15
+
+  # ── Test 5: mixed multi-root project attribution (#1060) ──
+  # First establish a mixed workspace and refresh it into WorkspaceNode roots.
+  # The smoke-test driver renders folder pickers as an internal quick input:
+  # entering an absolute folder path opens it, then the Add button confirms it.
+  - id: "invoke-add-non-java-root"
+    action: "executeVSCodeCommand workbench.action.addRootFolder"
+
+  - id: "type-non-java-root"
+    action: "fillQuickInput ${workspaceParent}/non-java"
+
+  - id: "confirm-non-java-root"
+    action: "tryClickButton Add"
+
+  - id: "wait-non-java-root-ready"
+    action: "waitForLanguageServer"
+    timeout: 120
+    skipLlmVerify: true
+
+  - id: "refresh-mixed-workspace"
+    action: "executeVSCodeCommand java.view.package.refresh"
+    waitBefore: 2
+
+  - id: "collapse-multi-root-explorer"
+    action: "collapseSidebarSection UNTITLED (WORKSPACE)"
+
+  - id: "focus-mixed-workspace"
+    action: "executeVSCodeCommand javaProjectExplorer.focus"
+    waitBefore: 2
+
+  - id: "verify-non-java-workspace-root"
+    action: "wait 1 seconds"
+    verifyTreeItem:
+      name: "non-java"
+    timeout: 15
+
+  # Add a Java folder after the mixed multi-root structure already exists and
+  # refresh it into the expected WorkspaceNode -> ProjectNode hierarchy.
+  - id: "invoke-add-java-root"
+    action: "executeVSCodeCommand workbench.action.addRootFolder"
+
+  - id: "type-java-root"
+    action: "fillQuickInput ${workspaceParent}/simple"
+
+  - id: "confirm-java-root"
+    action: "tryClickButton Add"
+
+  - id: "wait-java-root-ready"
+    action: "waitForLanguageServer"
+    timeout: 120
+    skipLlmVerify: true
+
+  - id: "refresh-added-java-root"
+    action: "executeVSCodeCommand java.view.package.refresh"
+
+  - id: "verify-java-workspace-root"
+    action: "executeVSCodeCommand javaProjectExplorer.focus"
+    verifyTreeItem:
+      name: "simple"
+      exact: true
+      count: 1
+      level: 1
+    timeout: 15
+
+  # Deterministically simulate the onDidProjectsImport path. Before #1060 this
+  # command appended a second top-level ProjectNode named "simple" beside the
+  # existing WorkspaceNode. The fixed provider ignores progressive insertion
+  # in multi-root workspaces, so exactly one level-1 row remains.
+  - id: "simulate-progressive-project-import"
+    action: 'executeVSCodeCommand _java.view.package.internal.addProjects ["${workspaceParentUri}/simple"]'
+    verifyTreeItem:
+      name: "simple"
+      exact: true
+      count: 1
+      level: 1
+    timeout: 15

test/index.ts

@@ -98,6 +98,17 @@ async function main(): Promise<void> {
             ],
         });
 
+        // Run multi-root workspace test
+        await runTests({
+            vscodeExecutablePath,
+            extensionDevelopmentPath,
+            extensionTestsPath: path.resolve(__dirname, "./multiple-suite"),
+            launchArgs: [
+                path.join(__dirname, "..", "..", "test", "multiple", "multiple-project.code-workspace"),
+                `--user-data-dir=${userDir}`,
+            ],
+        });
+
         // Run test for non-Java Gradle project (regression test for #921)
         await runTests({
             vscodeExecutablePath,

test/maven-suite/projectView.test.ts

@@ -277,6 +277,24 @@ suite("Maven Project View Tests", () => {
         assert.equal(mavenChildren[1].getDisplayName(), "junit:junit:4.13.1");
     });
 
+    test("Does not add duplicate progressive projects for equivalent URIs", async function() {
+        const explorer = DependencyExplorer.getInstance(contextManager.context);
+        await vscode.commands.executeCommand(Commands.VIEW_PACKAGE_REFRESH);
+
+        const roots = await explorer.dataProvider.getChildren();
+        assert.equal(roots?.length, 1, "Number of root nodes should be 1");
+        const projectNode = roots![0] as ProjectNode;
+        assert.ok(projectNode.uri, "Project node should have a URI");
+
+        const equivalentUri = projectNode.uri!.endsWith("/")
+            ? projectNode.uri!.replace(/\/+$/, "")
+            : `${projectNode.uri}/`;
+        explorer.dataProvider.addProgressiveProjects([equivalentUri]);
+
+        const updatedRoots = await explorer.dataProvider.getChildren();
+        assert.equal(updatedRoots?.length, 1, "Equivalent project URIs should be deduplicated");
+    });
+
     teardown(async () => {
         // Restore default settings. Some tests might alter them and others depend on a specific setting.
         // Not resetting to the default settings will also show the file as changed in the source control view.

test/multiple-suite/index.ts

@@ -0,0 +1,38 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT license.
+
+import * as glob from "glob";
+import * as Mocha from "mocha";
+import * as path from "path";
+
+export function run(): Promise<void> {
+    const mocha = new Mocha({
+        ui: "tdd",
+        color: true,
+        timeout: 1 * 60 * 1000,
+    });
+
+    const testsRoot = __dirname;
+
+    return new Promise((c, e) => {
+        glob("**/**.test.js", { cwd: testsRoot }, (err, files) => {
+            if (err) {
+                return e(err);
+            }
+
+            files.forEach((f) => mocha.addFile(path.resolve(testsRoot, f)));
+
+            try {
+                mocha.run((failures) => {
+                    if (failures > 0) {
+                        e(new Error(`${failures} tests failed.`));
+                    } else {
+                        c();
+                    }
+                });
+            } catch (err) {
+                e(err);
+            }
+        });
+    });
+}