Merge 2026.1

android-customization/resources/event-log-metadata/FUS/dictionaries/composer_packages.ndjson.meta

@@ -0,0 +1 @@
+1773941860000

android-customization/resources/event-log-metadata/FUS/dictionaries/dictionaries.json

@@ -1,3 +1,3 @@
 {
-  "dictionaries" : [ "crate_names.ndjson", "dotnet_technologies.ndjson", "grazie_rule_ids.ndjson", "grazie_rule_long_ids.ndjson", "ktor_feature_ids.ndjson", "look_and_feel.ndjson", "python_packages.ndjson" ]
+  "dictionaries" : [ "composer_packages.ndjson", "crate_names.ndjson", "dotnet_technologies.ndjson", "grazie_rule_ids.ndjson", "grazie_rule_long_ids.ndjson", "ktor_feature_ids.ndjson", "look_and_feel.ndjson", "python_packages.ndjson" ]
 }

android-customization/resources/event-log-metadata/FUS/dictionaries/dictionaries.json.meta

@@ -1 +1 @@
-1765643657
+1773937163000

android-customization/resources/event-log-metadata/FUS/dictionaries/python_packages.ndjson.meta

@@ -1 +1 @@
-1770308440
+1773937163000

android-customization/resources/event-log-metadata/FUS/events-scheme.json.meta

@@ -1 +1 @@
-1772487304
+1774352396000

android-customization/resources/event-log-metadata/JFUS/events-scheme.json.meta

@@ -1 +1 @@
-1768954085
+1773937163000

community-resources/resources/event-log-metadata/FUS/dictionaries/composer_packages.ndjson.meta

@@ -0,0 +1 @@
+1773941860000

community-resources/resources/event-log-metadata/FUS/dictionaries/dictionaries.json

@@ -1,3 +1,3 @@
 {
-  "dictionaries" : [ "crate_names.ndjson", "dotnet_technologies.ndjson", "grazie_rule_ids.ndjson", "grazie_rule_long_ids.ndjson", "ktor_feature_ids.ndjson", "look_and_feel.ndjson", "python_packages.ndjson" ]
+  "dictionaries" : [ "composer_packages.ndjson", "crate_names.ndjson", "dotnet_technologies.ndjson", "grazie_rule_ids.ndjson", "grazie_rule_long_ids.ndjson", "ktor_feature_ids.ndjson", "look_and_feel.ndjson", "python_packages.ndjson" ]
 }

community-resources/resources/event-log-metadata/FUS/dictionaries/dictionaries.json.meta

@@ -1 +1 @@
-1765562765
+1773937163000

community-resources/resources/event-log-metadata/FUS/dictionaries/python_packages.ndjson.meta

@@ -1 +1 @@
-1770308440
+1773937163000

community-resources/resources/event-log-metadata/FUS/events-scheme.json.meta

@@ -1 +1 @@
-1772487304
+1774352396000

community-resources/resources/event-log-metadata/LLMC/events-scheme.json.meta

@@ -1 +1 @@
-1772231476
+1774355576000

community-resources/resources/event-log-metadata/ML/events-scheme.json.meta

@@ -1 +1 @@
-1772457456
+1774355576000

community-resources/resources/event-log-metadata/MLSE/events-scheme.json.meta

@@ -1 +1 @@
-1768926036
+1773937163000

community-resources/resources/event-log-metadata/MTHC/events-scheme.json.meta

@@ -1 +1 @@
-1772119944
+1773937163000

community-resources/resources/event-log-metadata/TRACE/events-scheme.json.meta

@@ -1 +1 @@
-1772229793
+1774355576000

community-resources/resources/idea/IdeaApplicationInfo.xml

@@ -1,7 +1,7 @@
 <component xmlns="http://jetbrains.org/intellij/schema/application-info">
-  <version major="2026" minor="1" suffix="RC"/>
+  <version major="2026" minor="1"/>
   <company name="JetBrains s.r.o." url="https://www.jetbrains.com"/>
-  <build number="IC-__BUILD__" date="__BUILD_DATE__" majorReleaseDate="20260324" />
+  <build number="IC-__BUILD__" date="__BUILD_DATE__" majorReleaseDate="20260325" />
   <logo url="/idea_community_logo.png"/>
   <icon svg="/idea-ce.svg" svg-small="/idea-ce_16.svg"/>
   <icon-eap svg="/idea-ce-eap.svg" svg-small="/idea-ce-eap_16.svg"/>

java/java-impl/resources/com/intellij/internal/statistic/libraryUsage/library-usage-statistics.xml

@@ -228,8 +228,15 @@
   <technology name="kotlinx-datetime" root="kotlinx.datetime"/>
   <technology name="kotlinx-html" root="kotlinx.html"/>
   <technology name="kotlinx-io" root="kotlinx.io"/>
-  <technology name="kotlinx-jupyter-ktor-client" root="org.jetbrains.kotlinx.jupyter.ktor.client"/>
+  <technology name="kotlinx-jupyter-database" root="org.jetbrains.kotlinx.jupyter.database"/>
+  <technology name="kotlinx-jupyter-intellij-platform" root="org.jetbrains.kotlinx.jupyter.intellij"/>
   <technology name="kotlinx-jupyter-json-generation" root="org.jetbrains.kotlinx.jupyter.json"/>
+  <technology name="kotlinx-jupyter-json2kt" root="org.jetbrains.kotlinx.jupyter.json2kt"/>
+  <technology name="kotlinx-jupyter-ktor-client" root="org.jetbrains.kotlinx.jupyter.ktor.client"/>
+  <technology name="kotlinx-jupyter-notebook-parser" root="org.jetbrains.jupyter.parser"/>
+  <technology name="kotlinx-jupyter-notekit" root="org.jetbrains.kotlinx.jupyter.notebook"/>
+  <technology name="kotlinx-jupyter-serialization" root="org.jetbrains.kotlinx.jupyter.serialization"/>
+  <technology name="kotlinx-jupyter-widgets" root="org.jetbrains.kotlinx.jupyter.widget"/>
   <technology name="kotlin-logging" root="io.github.oshai.kotlinlogging"/>
   <technology name="kotlinx-serialization" root="kotlinx.serialization"/>
   <technology name="ktlint" root="com.pinterest.ktlint"/>

platform/lang-impl/src/com/intellij/codeInsight/lookup/impl/LookupUsageTracker.java

@@ -57,7 +57,7 @@
 public final class LookupUsageTracker extends CounterUsagesCollector {
   public static final String FINISHED_EVENT_ID = "finished";
   public static final String GROUP_ID = "completion";
-  public static final EventLogGroup GROUP = new EventLogGroup(GROUP_ID, 40);
+  public static final EventLogGroup GROUP = new EventLogGroup(GROUP_ID, 41);
   private static final EventField<String> SCHEMA = EventFields.StringValidatedByCustomRule("schema", FileTypeSchemaValidator.class);
   private static final BooleanEventField ALPHABETICALLY = EventFields.Boolean("alphabetically");
   private static final EnumEventField<EditorKind> EDITOR_KIND = EventFields.Enum("editor_kind", EditorKind.class);

platform/lang-impl/src/com/intellij/ide/projectView/impl/FileNestingBuilder.java

@@ -9,6 +9,7 @@
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.util.containers.MultiMap;
+import com.intellij.util.containers.OrderedSet;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -43,7 +44,7 @@ public static FileNestingBuilder getInstance() {
     final long modCount = fileNestingService.getModificationCount();
 
     if (myNestingRules == null || myBaseListModCount != modCount) {
-      myNestingRules = new HashSet<>();
+      myNestingRules = new OrderedSet<>();
       myBaseListModCount = modCount;
 
       final MultiMap<String, String> childToParentSuffix = new MultiMap<>();

platform/platform-impl/initial-config-import/src/com/intellij/openapi/application/ConfigImportHelper.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2025 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+// Copyright 2000-2026 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.openapi.application;
 
 import com.intellij.configurationStore.StoreUtilKt;
@@ -36,6 +36,7 @@
 import com.intellij.openapi.application.migrations.Localization242;
 import com.intellij.openapi.application.migrations.NotebooksMigration242;
 import com.intellij.openapi.application.migrations.SpaceMigration252;
+import com.intellij.openapi.application.migrations.VcsPluginsMigration261;
 import com.intellij.openapi.components.StoragePathMacros;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.extensions.PluginId;
@@ -144,6 +145,8 @@ public final class ConfigImportHelper {
   private static final long PLUGIN_UPDATES_TIMEOUT_MS = 7000L;
   private static final long BROKEN_PLUGINS_TIMEOUT_MS = 3000L;
 
+  private static boolean isUnitTestMode = false;
+
   private ConfigImportHelper() { }
 
   public static void importConfigsTo(
@@ -155,6 +158,9 @@ public static void importConfigsTo(
     log.info("Importing configs to '" + newConfigDir + "'; veryFirstStart=" + veryFirstStartOnThisComputer);
     System.setProperty(InitialConfigImportState.FIRST_SESSION_KEY, Boolean.TRUE.toString());
 
+    var app = ApplicationManager.getApplication();
+    isUnitTestMode = app != null && app.isUnitTestMode();
+
     var migrationOption = CustomConfigMigrationOption.readCustomConfigMigrationOptionAndRemoveMarkerFile(newConfigDir);
     log.info("Custom migration option: " + migrationOption);
     var importSettings = findCustomConfigImportSettings();
@@ -1021,7 +1027,9 @@ public static void migratePlugins(
       }
     }
 
-    migrateGlobalPlugins(newConfigDir, oldConfigDir, pluginsToMigrate, pluginsToDownload, options.log);
+    if (!isUnitTestMode) {
+      migrateGlobalPlugins(newConfigDir, oldConfigDir, pluginsToMigrate, pluginsToDownload, options.log);
+    }
 
     pluginsToMigrate.removeIf(hasPendingUpdate);
     if (!pluginsToMigrate.isEmpty()) {
@@ -1123,6 +1131,7 @@ private static void performMigrations(PluginMigrationOptions options) {
     new NotebooksMigration242().migratePlugins(options);
     new SpaceMigration252().migratePlugins(options);
     new BigDataToolsMigration253().migratePlugins(options);
+    new VcsPluginsMigration261().migratePlugins(options);
     new CwmMigration261().migratePlugins(options);
   }
 
@@ -1143,7 +1152,7 @@ private static void migrateGlobalPlugins(
       Files.writeString(resultFile, downloadIds);
     }
     catch (IOException e) {
-      options.getLog().error("Unable to write auto install result", e);
+      log.error("Unable to write auto install result", e);
     }
   }
 

platform/platform-impl/src/com/intellij/openapi/application/migrations/VcsPluginsMigration261.kt

@@ -0,0 +1,16 @@
+// Copyright 2000-2026 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.openapi.application.migrations
+
+private const val PERFORCE_PLUGIN_ID = "PerforceDirectPlugin"
+private const val MERCURIAL_PLUGIN_ID = "hg4idea"
+private const val SUBVERSION_PLUGIN_ID = "Subversion"
+
+private val UNBUNDLED_VCS_PLUGINS = listOf(PERFORCE_PLUGIN_ID, MERCURIAL_PLUGIN_ID, SUBVERSION_PLUGIN_ID)
+
+internal class VcsPluginsMigration261 : PluginMigration() {
+  override fun migratePlugins(descriptor: PluginMigrationDescriptor) {
+    for (pluginId in UNBUNDLED_VCS_PLUGINS) {
+      descriptor.addPluginIfNeeded(pluginId)
+    }
+  }
+}

platform/platform-impl/src/com/intellij/openapi/editor/impl/InlineInlayImpl.java

@@ -76,8 +76,11 @@ public void dispose() {
   void doUpdate() {
     myWidthInPixels = myRenderer.calcWidthInPixels(this);
     if (myWidthInPixels <= 0) {
-      throw PluginException.createByClass("Positive width should be defined for an inline element by " + myRenderer, null,
-                                          myRenderer.getClass());
+      throw PluginException.createByClass(
+        "Positive width should be defined for an inline element by " + myRenderer +
+        " (class=" + myRenderer.getClass().getName() + ", valid=" + isValid() + ", myWidthInPixels=" + myWidthInPixels + ")",
+        null, myRenderer.getClass()
+      );
     }
   }
 

platform/testFramework/junit5/src/fixture/fixtures.kt

@@ -199,12 +199,13 @@ fun TestFixture<Project>.moduleFixture(
 fun TestFixture<Project>.moduleFixture(
   pathFixture: TestFixture<Path>,
   addPathToSourceRoot: Boolean = false,
+  moduleTypeId: String = ""
 ): TestFixture<Module> = testFixture { _ ->
   val project = this@moduleFixture.init()
   val path = pathFixture.init()
   val manager = ModuleManager.getInstance(project)
   val module = edtWriteAction {
-    manager.newModule(path, "")
+    manager.newModule(path, moduleTypeId)
   }
   if (addPathToSourceRoot) {
     val pathVfs = withContext(Dispatchers.IO) {

platform/vcs-impl/src/com/intellij/ide/actions/StartUseVcsDialog.java

@@ -16,6 +16,7 @@
 import com.intellij.util.ui.JBInsets;
 import com.intellij.util.ui.JBUI;
 import com.intellij.util.ui.dialog.VcsDialogUtils;
+import kotlin.Unit;
 import org.jetbrains.annotations.NotNull;
 
 import javax.swing.JComponent;
@@ -67,7 +68,10 @@ protected JComponent createCenterPanel() {
 
     ++gb.gridx;
 
-    mainPanel.add(VcsDialogUtils.getMorePluginsLink(mainPanel), gb);
+    mainPanel.add(VcsDialogUtils.getMorePluginsLink(mainPanel, () -> {
+      close(CANCEL_EXIT_CODE);
+      return Unit.INSTANCE;
+    }), gb);
 
     JPanel wrapper = new JPanel(new GridBagLayout());
     GridBagConstraints gbc = new GridBagConstraints(0, 0, 1, 1, 1, 1, GridBagConstraints.NORTHWEST, GridBagConstraints.NONE,

platform/xdebugger-api/api-dump.txt

@@ -105,6 +105,7 @@ com.intellij.xdebugger.XDebugSession
 - a:reportMessage(java.lang.String,com.intellij.openapi.ui.MessageType,javax.swing.event.HyperlinkListener):V
 - a:resume():V
 - a:runToPosition(com.intellij.xdebugger.XSourcePosition,Z):V
+- runWhenUiReady(java.util.function.Consumer):V
 - a:sessionResumed():V
 - a:setBreakpointInvalid(com.intellij.xdebugger.breakpoints.XLineBreakpoint,java.lang.String):V
 - a:setBreakpointMuted(Z):V

platform/xdebugger-api/src/com/intellij/xdebugger/XDebugSession.java

@@ -11,6 +11,7 @@
 import com.intellij.execution.ui.RunnerLayoutUi;
 import com.intellij.openapi.Disposable;
 import com.intellij.openapi.actionSystem.DataKey;
+import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.ui.MessageType;
 import com.intellij.openapi.util.NlsContexts;
@@ -27,6 +28,7 @@
 
 import javax.swing.Icon;
 import javax.swing.event.HyperlinkListener;
+import java.util.function.Consumer;
 
 /**
  * Instances of this class are created by the debugging subsystem
@@ -209,13 +211,26 @@ default void reportMessage(@NotNull @NlsContexts.NotificationContent String mess
    * To migrate, please use one of the following approaches:
    * <ul>
    *   <li>Use {@link XDebugProcess#createTabLayouter()} to create static tabs. Note that this option still uses LUX.</li>
-   *   <li>Use {@link com.intellij.xdebugger.impl.XDebugSessionImpl#runWhenUiReady} as a temporary workaround to avoid races.</li>
-   *   <li>Use {@link com.intellij.platform.debugger.impl.shared.proxy.XDebugSessionProxy#getSessionTab()} to add a tab on the frontend.</li>
+   *   <li>Use {@link #runWhenUiReady} as a temporary workaround to avoid races.</li>
+   *   <li>(internal) Use {@link com.intellij.platform.debugger.impl.shared.proxy.XDebugSessionProxy#getSessionTab()} to add a tab on the frontend.</li>
    * </ul>
    */
   @ApiStatus.Obsolete
   @Nullable RunnerLayoutUi getUI();
 
+  /**
+   * Calls <code>block</code> in EDT when the tab UI is ready.
+   * <p>
+   * See {@link #getUI()} doc for proper migration steps.
+   */
+  @ApiStatus.Obsolete
+  default void runWhenUiReady(@NotNull Consumer<@NotNull RunnerLayoutUi> block) {
+    var ui = getUI();
+    if (ui != null) {
+      ApplicationManager.getApplication().invokeLater(() -> block.accept(ui));
+    }
+  }
+
   @ApiStatus.Internal
   boolean isMixedMode();
 

platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.kt

@@ -510,6 +510,7 @@ class XDebugSessionImpl @JvmOverloads constructor(
    * Use [runWhenTabReady] to avoid races.
    */
   val sessionTab: XDebugSessionTab?
+    @ApiStatus.Obsolete
     get() {
       if (SplitDebuggerMode.showSplitWarnings()) {
         // See "TODO [Debugger.sessionTab]" to see usages which are not yet properly migrated.
@@ -559,13 +560,7 @@ class XDebugSessionImpl @JvmOverloads constructor(
     }
   }
 
-  /**
-   * Calls [block] in EDT when the tab UI is ready.
-   *
-   * See [XDebugSession.getUI] doc for proper migration steps.
-   */
-  @ApiStatus.Obsolete
-  fun runWhenUiReady(block: (RunnerLayoutUi) -> Unit) {
+  override fun runWhenUiReady(block: Consumer<RunnerLayoutUi>) {
     tabCoroutineScope.launch(Dispatchers.EDT) {
       assertSessionTabInitialized()
       val ui = if (SplitDebuggerMode.isSplitDebugger() && AppMode.isRemoteDevHost()) {
@@ -575,7 +570,7 @@ class XDebugSessionImpl @JvmOverloads constructor(
         mySessionTab.await()?.ui
       }
       if (ui != null) {
-        block(ui)
+        block.accept(ui)
       }
     }
   }

plugins/maven/src/main/java/org/jetbrains/idea/maven/execution/build/DelegateBuildRunner.kt

@@ -44,8 +44,12 @@ internal class DelegateBuildRunner : DefaultJavaProgramRunner() {
     return result.get()
   }
 
+  /**
+   * The runner serves only "Delegate IDE Build/Run Actions to Maven", the platform should not choose this runner when filtering.
+   * It must be obtained directly by ID or via [Util.getDelegateRunner]
+   */
   override fun canRun(executorId: String, profile: RunProfile): Boolean {
-    return executorId == DefaultRunExecutor.EXECUTOR_ID && profile is MavenRunConfiguration
+    return false
   }
 
   override fun doExecuteAsync(state: TargetEnvironmentAwareRunProfileState, env: ExecutionEnvironment): Promise<RunContentDescriptor?> {

plugins/maven/src/test/java/org/jetbrains/idea/maven/execution/DelegateBuildRunnerCanRunTest.kt

@@ -11,12 +11,12 @@ import org.junit.Test
 class DelegateBuildRunnerCanRunTest : MavenExecutionTestCase() {
 
   @Test
-  fun testAcceptsMavenRunConfiguration() {
+  fun testDoesNotMavenRunConfiguration() {
     val runner = ProgramRunner.findRunnerById(DELEGATE_RUNNER_ID)?: throw AssertionError("[$DELEGATE_RUNNER_ID] build runner should be registered")
     val mavenFactory = MavenRunConfigurationType.getInstance().configurationFactories[0]
     val mavenConfiguration = mavenFactory.createTemplateConfiguration(project)
 
-    assertTrue(
+    assertFalse(
       "Delegate build runner must accept Maven run configuration with DefaultRunExecutor",
       runner.canRun(DefaultRunExecutor.EXECUTOR_ID, mavenConfiguration)
     )

plugins/terminal/frontend/src/com/intellij/terminal/frontend/toolwindow/impl/TerminalDirectoryDnD.kt

@@ -13,13 +13,16 @@ import com.intellij.psi.PsiElement
 import com.intellij.psi.PsiFile
 import com.intellij.ui.content.ContentManager
 import com.intellij.util.ui.UIUtil
+import org.jetbrains.plugins.terminal.fus.TerminalOpeningWay
+import org.jetbrains.plugins.terminal.fus.TerminalStartupFusInfo
 
 /**
  * Creates the new terminal tab on dropping the directory node inside the terminal tool window.
  * For example, from Project View.
  */
 internal fun installDirectoryDnD(window: ToolWindowEx, parentDisposable: Disposable) {
   val handler = DnDDropHandler { event ->
+    val fusInfo = TerminalStartupFusInfo(TerminalOpeningWay.DND_FILE_TO_TOOLWINDOW)
     val tw = event.getAttachedObject() as? TransferableWrapper ?: return@DnDDropHandler
     val dir = getDirectory(tw.getPsiElements()?.singleOrNull()) ?: return@DnDDropHandler
     // Find the right split to create the new tab in
@@ -28,6 +31,7 @@ internal fun installDirectoryDnD(window: ToolWindowEx, parentDisposable: Disposa
       window.project,
       workingDirectory = dir.getVirtualFile().getPath(),
       contentManager = nearestManager,
+      startupFusInfo = fusInfo
     )
   }
   DnDSupport.createBuilder(window.decorator)