Option to auto-reload changed plugins without IDE restart (for plugin developers)

GitOrigin-RevId: f15ccc3dc194fb76d966706abeef3fc0202a7e6d

platform/platform-impl/src/com/intellij/ide/plugins/DynamicPluginVfsListener.kt

@@ -0,0 +1,85 @@
+// Copyright 2000-2020 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.ide.plugins
+
+import com.intellij.ide.FrameStateListener
+import com.intellij.notification.NotificationType
+import com.intellij.openapi.application.ApplicationManager
+import com.intellij.openapi.application.PathManager
+import com.intellij.openapi.extensions.PluginDescriptor
+import com.intellij.openapi.util.io.FileUtil
+import com.intellij.openapi.vfs.AsyncFileListener
+import com.intellij.openapi.vfs.LocalFileSystem
+import com.intellij.openapi.vfs.VfsUtilCore
+import com.intellij.openapi.vfs.newvfs.events.VFileContentChangeEvent
+import com.intellij.openapi.vfs.newvfs.events.VFileEvent
+
+/**
+ * @author yole
+ */
+private const val AUTO_RELOAD_PLUGINS_SYSTEM_PROPERTY = "idea.auto.reload.plugins"
+
+class DynamicPluginVfsListener : AsyncFileListener {
+  init {
+    if (System.getProperty(AUTO_RELOAD_PLUGINS_SYSTEM_PROPERTY) != null) {
+      val pluginsPath = PathManager.getPluginsPath()
+      LocalFileSystem.getInstance().addRootToWatch(pluginsPath, true)
+      val pluginsRoot = LocalFileSystem.getInstance().findFileByPath(pluginsPath)
+      if (pluginsRoot != null) {
+        // ensure all plugins are in VFS
+        VfsUtilCore.processFilesRecursively(pluginsRoot) { true }
+      }
+    }
+  }
+
+  override fun prepareChange(events: MutableList<out VFileEvent>): AsyncFileListener.ChangeApplier? {
+    if (System.getProperty(AUTO_RELOAD_PLUGINS_SYSTEM_PROPERTY) == null) return null
+
+    val pluginsToReload = hashSetOf<PluginDescriptor>()
+    for (event in events) {
+      if (!event.isFromRefresh) continue
+      if (event is VFileContentChangeEvent) {
+        findPluginByPath(event.path)?.let { pluginsToReload.add(it) }
+      }
+    }
+    val descriptorsToReload = pluginsToReload
+      .filter { it.isEnabled }
+      .map { PluginEnabler.loadFullDescriptor(it) }
+      .filter { DynamicPlugins.allowLoadUnloadWithoutRestart(it) }
+
+    if (descriptorsToReload.isEmpty()) return null
+
+    return object : AsyncFileListener.ChangeApplier {
+      override fun afterVfsChange() {
+        ApplicationManager.getApplication().invokeLater {
+          val reloaded = mutableListOf<String>()
+          for (pluginDescriptor in descriptorsToReload) {
+            if (!DynamicPlugins.unloadPlugin(pluginDescriptor, isUpdate = true)) {
+              continue
+            }
+            reloaded.add(pluginDescriptor.name)
+            DynamicPlugins.loadPlugin(pluginDescriptor, false)
+          }
+          if (reloaded.isNotEmpty()) {
+            DynamicPlugins.notify("${reloaded.joinToString()} reloaded successfully", NotificationType.INFORMATION)
+          }
+        }
+      }
+    }
+  }
+
+  private fun findPluginByPath(path: String): PluginDescriptor? {
+    if (!FileUtil.isAncestor(PathManager.getPluginsPath(), path, false)) return null
+    return PluginManager.getPlugins().firstOrNull {
+      FileUtil.isAncestor(it.path.absolutePath, path, false)
+    }
+  }
+}
+
+class DynamicPluginsFrameStateListener : FrameStateListener {
+  override fun onFrameActivated() {
+    if (System.getProperty(AUTO_RELOAD_PLUGINS_SYSTEM_PROPERTY) == null) return
+
+    val pluginsRoot = LocalFileSystem.getInstance().findFileByPath(PathManager.getPluginsPath())
+    pluginsRoot?.refresh(true, true)
+  }
+}

platform/platform-impl/src/com/intellij/ide/plugins/DynamicPlugins.kt

@@ -357,8 +357,7 @@ object DynamicPlugins {
           val snapshotDate = SimpleDateFormat("dd.MM.yyyy_HH.mm.ss").format(Date())
           val snapshotPath = "$snapshotFolder/unload-${pluginDescriptor.pluginId}-$snapshotDate.hprof"
           MemoryDumpHelper.captureMemoryDump(snapshotPath)
-          GROUP.createNotification("Captured memory snapshot on plugin unload fail: $snapshotPath",
-                                   NotificationType.WARNING).notify(null)
+          notify("Captured memory snapshot on plugin unload fail: $snapshotPath", NotificationType.WARNING)
         }
         LOG.info("Plugin ${pluginDescriptor.pluginId} is not unload-safe because class loader cannot be unloaded")
       }
@@ -367,6 +366,10 @@ object DynamicPlugins {
     }
   }
 
+  internal fun notify(text: String, notificationType: NotificationType) {
+    GROUP.createNotification(text, notificationType).notify(null)
+  }
+
   private fun unloadPluginDescriptor(pluginDescriptor: IdeaPluginDescriptorImpl,
                                      loadedPluginDescriptor: IdeaPluginDescriptorImpl) {
     val application = ApplicationManager.getApplication() as ApplicationImpl

platform/platform-resources/src/META-INF/PlatformExtensions.xml

@@ -901,5 +901,9 @@
     <titleInfoProvider implementation="com.intellij.openapi.wm.impl.simpleTitleParts.ProductVersionTitleInfoProvider"/>
     <titleInfoProvider implementation="com.intellij.openapi.wm.impl.simpleTitleParts.SuperUserSuffixTitleInfoProvider"/>
 
+    <vfs.asyncListener implementation="com.intellij.ide.plugins.DynamicPluginVfsListener"/>
   </extensions>
+  <applicationListeners>
+    <listener class="com.intellij.ide.plugins.DynamicPluginsFrameStateListener" topic="com.intellij.ide.FrameStateListener"/>
+  </applicationListeners>
 </idea-plugin>