IJPL-207762 support command completion completion items on frontend

GitOrigin-RevId: 7efdfb02dad77e0ee9ca276e14b2b6de89f53120

platform/analysis-api/src/com/intellij/codeInsight/completion/NewRdCompletionSupport.kt

@@ -19,6 +19,8 @@ interface NewRdCompletionSupport {
    */
   fun scheduleAutopopup(project: Project, editor: Editor, completionType: CompletionType)
 
+  fun isFrontendForIntelliJBackendImpl(): Boolean
+
   companion object {
     @JvmStatic
     fun isFrontendRdCompletionOn(): Boolean = service<NewRdCompletionSupport>().isFrontendRdCompletionOnImpl()
@@ -32,6 +34,9 @@ interface NewRdCompletionSupport {
 
     @JvmStatic
     fun getInstance(): NewRdCompletionSupport = service<NewRdCompletionSupport>()
+
+    fun isFrontendForIntelliJBackend(): Boolean =
+      getInstance().isFrontendForIntelliJBackendImpl()
   }
 }
 
@@ -40,4 +45,6 @@ internal class NoOpNewCompletionSupport : NewRdCompletionSupport {
 
   override fun scheduleAutopopup(project: Project, editor: Editor, completionType: CompletionType) =
     throw UnsupportedOperationException("Is not expected to be called, use AutopopupController directly instead")
+
+  override fun isFrontendForIntelliJBackendImpl(): Boolean = false
 }

platform/completion/common/src/protocol/RpcCompletionItem.kt

@@ -3,6 +3,7 @@ package com.intellij.platform.completion.common.protocol
 
 import com.intellij.codeInsight.completion.CodeCompletionHandlerBase
 import com.intellij.codeInsight.completion.CompletionResult
+import com.intellij.codeInsight.completion.command.RemDevCommandCompletionHelpers
 import com.intellij.codeInsight.lookup.AutoCompletionPolicy
 import com.intellij.codeInsight.lookup.LookupElement
 import com.intellij.codeInsight.lookup.LookupElementInsertStopper
@@ -24,6 +25,7 @@ data class RpcCompletionItem(
   val shouldStopLookupInsertion: Boolean = false,
   val isDirectInsertion: Boolean = false,
   val isWorthShowingInAutoPopup: Boolean = false,
+  val commandState: RemDevCommandCompletionHelpers.CommandState? = null
 ) {
   override fun toString(): String = buildToString("RpcCompletionItem") {
     field("id", id)
@@ -61,6 +63,7 @@ fun CompletionResult.toRpc(): RpcCompletionItem {
     isDirectInsertion = element.getUserData(CodeCompletionHandlerBase.DIRECT_INSERTION) != null,
     prefixMatcher = prefixMatcher.toRpc(id),
     isWorthShowingInAutoPopup = element.isWorthShowingInAutoPopup(),
+    commandState = RemDevCommandCompletionHelpers.getCommandState(element)
   )
 }
 

platform/lang-impl/src/com/intellij/codeInsight/completion/command/CommandCompletionService.kt

@@ -2,6 +2,8 @@
 package com.intellij.codeInsight.completion.command
 
 import com.intellij.codeInsight.CodeInsightBundle
+import com.intellij.codeInsight.completion.command.RemDevCommandCompletionHelpers.isCommand
+import com.intellij.codeInsight.completion.command.RemDevCommandCompletionHelpers.isPostfix
 import com.intellij.codeInsight.completion.command.configuration.ApplicationCommandCompletionService
 import com.intellij.codeInsight.daemon.impl.HintRenderer
 import com.intellij.codeInsight.editorLineStripeHint.EditorLineStripeTextRenderer
@@ -16,7 +18,6 @@ import com.intellij.codeInsight.lookup.LookupManagerListener
 import com.intellij.codeInsight.lookup.impl.LookupCustomizer
 import com.intellij.codeInsight.lookup.impl.LookupImpl
 import com.intellij.codeInsight.template.impl.TemplateColors
-import com.intellij.codeInsight.template.postfix.completion.PostfixTemplateLookupElement
 import com.intellij.codeInsight.template.postfix.settings.PostfixTemplatesSettings
 import com.intellij.lang.Language
 import com.intellij.lang.LanguageExtension
@@ -136,7 +137,7 @@ internal class CommandCompletionService(
     if (showIfMeaningless) {
       lookup.showIfMeaningless() // stop hiding
     }
-    lookup.arranger.additionalMatcher = CommandCompletionLookupItemMatcher(PostfixTemplatesSettings.getInstance().isShowAsSeparateGroup)
+    lookup.arranger.additionalMatcher = CommandCompletionLookupItemMatcher(PostfixTemplatesSettings.getInstance().isShowAsSeparateGroup) // todo settings move frontend
     lookup.arranger.prefixChanged(lookup)
     lookup.requestResize()
     lookup.refreshUi(false, true)
@@ -186,15 +187,14 @@ internal class CommandCompletionService(
   }
 
   private class CommandCompletionLookupItemMatcher(private val showPostfixAsSeparateGroup: Boolean) : Condition<LookupElement> {
-    override fun value(e: LookupElement): Boolean =
-      e.`as`(CommandCompletionLookupElement::class.java) != null ||
-      (showPostfixAsSeparateGroup && e.`as`(PostfixTemplateLookupElement::class.java) != null)
+    override fun value(element: LookupElement): Boolean =
+      isCommand(element) ||
+      (showPostfixAsSeparateGroup && isPostfix(element))
   }
 
   private object NotPostfixCompletionLookupItemMatcher : Condition<LookupElement> {
-    override fun value(e: LookupElement?): Boolean {
-      return e != null && e.`as`(PostfixTemplateLookupElement::class.java) == null
-    }
+    override fun value(element: LookupElement): Boolean =
+      !isPostfix(element)
   }
 }
 

platform/lang-impl/src/com/intellij/codeInsight/completion/command/RemDevCommandCompletionHelpers.kt

@@ -0,0 +1,39 @@
+// 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.codeInsight.completion.command
+
+import com.intellij.codeInsight.lookup.LookupElement
+import com.intellij.codeInsight.template.postfix.completion.PostfixTemplateLookupElement
+import com.intellij.openapi.util.Key
+import org.jetbrains.annotations.ApiStatus
+
+@ApiStatus.Internal
+object RemDevCommandCompletionHelpers {
+  enum class CommandState {
+    Postfix,
+    Command,
+  }
+
+  private val COMMAND_FLAG: Key<CommandState> = Key("COMMAND_FLAG")
+
+  fun isPostfix(element: LookupElement): Boolean =
+    element.`as`(PostfixTemplateLookupElement::class.java) != null ||
+    element.getUserData(COMMAND_FLAG) == CommandState.Postfix
+
+  fun isCommand(element: LookupElement): Boolean =
+    element.`as`(CommandCompletionLookupElement::class.java) != null ||
+    element.getUserData(COMMAND_FLAG) == CommandState.Command
+
+  fun getCommandState(element: LookupElement): CommandState? {
+    val flag = element.getUserData(COMMAND_FLAG)
+    return when {
+        flag != null -> flag
+        isCommand(element) -> CommandState.Command
+        isPostfix(element) -> CommandState.Postfix
+        else -> null
+    }
+  }
+
+  fun installCommandState(element: LookupElement, commandState: CommandState?) {
+    element.putUserData(COMMAND_FLAG, commandState)
+  }
+}

platform/lang-impl/src/com/intellij/codeInsight/completion/command/configuration/ApplicationCommandCompletionService.kt

@@ -1,6 +1,7 @@
 // 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.codeInsight.completion.command.configuration
 
+import com.intellij.codeInsight.completion.NewRdCompletionSupport
 import com.intellij.openapi.application.ApplicationManager
 import com.intellij.openapi.components.PersistentStateComponent
 import com.intellij.openapi.components.RoamingType
@@ -118,12 +119,27 @@ internal class AppCommandCompletionSettings(
   }
 
   private fun calculateFromRegistry(): Boolean {
+    // unit tests
     if (ApplicationManager.getApplication().isUnitTestMode() &&
-        Registry.`is`("ide.completion.command.force.enabled")) return true
-    if (!PlatformUtils.isIntelliJ()) return false
-    return Registry.`is`("ide.completion.command.force.enabled") ||
-           (!ApplicationManager.getApplication().isUnitTestMode() &&
-            Registry.`is`("ide.completion.command.enabled"))
+        Registry.`is`("ide.completion.command.force.enabled")) {
+      return true
+    }
+
+    // production
+    if (
+      PlatformUtils.isIntelliJ() ||
+      NewRdCompletionSupport.isFrontendRdCompletionOn() && NewRdCompletionSupport.isFrontendForIntelliJBackend()
+    ) {
+      if (Registry.`is`("ide.completion.command.force.enabled")) {
+        return true
+      }
+
+      if (Registry.`is`("ide.completion.command.enabled")) {
+        return !ApplicationManager.getApplication().isUnitTestMode()
+      }
+    }
+
+    return false
   }
 }