Add support for hlsearch variable

src/main/java/com/maddyhome/idea/vim/newapi/IjVimSearchGroup.kt

@@ -110,6 +110,19 @@ open class IjVimSearchGroup : VimSearchGroupBase(), PersistentStateComponent<Ele
     showSearchHighlight = injector.globalOptions().hlsearch
   }
 
+  override fun isSomeTextHighlighted(): Boolean {
+    val vimEditors = injector.editorGroup.getEditors().filter {
+      (injector.application.isUnitTest() || it.ij.component.isShowing)
+    }
+    for (vimEditor in vimEditors) {
+      val editor = vimEditor.ij
+      if (editor.vimLastHighlighters != null) {
+        return true
+      }
+    }
+    return false
+  }
+
   override fun setShouldShowSearchHighlights() {
     showSearchHighlight = injector.globalOptions().hlsearch
   }

src/test/java/org/jetbrains/plugins/ideavim/ex/implementation/variables/HighLightVariableTest.kt

@@ -0,0 +1,94 @@
+/*
+ * Copyright 2003-2024 The IdeaVim authors
+ *
+ * Use of this source code is governed by an MIT-style
+ * license that can be found in the LICENSE.txt file or at
+ * https://opensource.org/licenses/MIT.
+ */
+
+package org.jetbrains.plugins.ideavim.ex.implementation.variables
+
+import org.jetbrains.plugins.ideavim.VimTestCase
+import org.junit.jupiter.api.Test
+
+class HighLightVariableTest : VimTestCase() {
+
+  @Test
+  fun `test v hlsearch is initially false`() {
+    configureByText(
+      """
+    |one two one
+    |${c}three four three
+    |five six five
+    """.trimMargin()
+    )
+    enterCommand("set hlsearch")
+    enterCommand("echo v:hlsearch")
+    assertExOutput("0")
+  }
+
+  @Test
+  fun `test v hlsearch is true after successful search`() {
+    configureByText(
+      """
+    |one two one
+    |${c}three four three
+    |five six five
+    """.trimMargin()
+    )
+    enterCommand("set hlsearch")
+    enterSearch("one")
+    enterCommand("echo v:hlsearch")
+    assertExOutput("1")
+  }
+
+  @Test
+  fun `test v hlsearch is false after search with no matches`() {
+    configureByText(
+      """
+    |one two one
+    |${c}three four three
+    |five six five
+    """.trimMargin()
+    )
+    enterCommand("set hlsearch")
+    enterSearch("xyz")
+    enterCommand("echo v:hlsearch")
+    assertExOutput("0")
+  }
+
+  @Test
+  fun `test v hlsearch is false after nohlsearch command`() {
+    configureByText(
+      """
+    |one two one
+    |${c}three four three
+    |five six five
+    """.trimMargin()
+    )
+    enterCommand("set hlsearch")
+    enterSearch("one")
+    enterCommand("nohlsearch")
+    enterCommand("echo v:hlsearch")
+    assertExOutput("0")
+  }
+
+  @Test
+  fun `test v hlsearch is true after n command reuses previous search`() {
+    configureByText(
+      """
+    |one two one
+    |${c}three four three
+    |five six five
+    """.trimMargin()
+    )
+    enterCommand("set hlsearch")
+    enterSearch("one")
+    enterCommand("nohlsearch")
+    typeText("n")
+    enterCommand("echo v:hlsearch")
+    assertExOutput("1")
+  }
+
+
+}

vim-engine/src/main/kotlin/com/maddyhome/idea/vim/api/VimSearchGroup.kt

@@ -195,4 +195,9 @@ interface VimSearchGroup {
    * Gets the direction lastly used in a search.
    */
   fun getLastSearchDirection(): Direction
+
+  /**
+   * Returns true if any text is selected in the visible editors, false otherwise.
+   */
+  fun isSomeTextHighlighted(): Boolean
 }

vim-engine/src/main/kotlin/com/maddyhome/idea/vim/vimscript/model/variables/HighLightVariable.kt

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2003-2024 The IdeaVim authors
+ *
+ * Use of this source code is governed by an MIT-style
+ * license that can be found in the LICENSE.txt file or at
+ * https://opensource.org/licenses/MIT.
+ */
+
+package com.maddyhome.idea.vim.vimscript.model.variables
+
+import com.maddyhome.idea.vim.api.ExecutionContext
+import com.maddyhome.idea.vim.api.VimEditor
+import com.maddyhome.idea.vim.api.injector
+import com.maddyhome.idea.vim.vimscript.model.VimLContext
+import com.maddyhome.idea.vim.vimscript.model.datatypes.VimDataType
+import com.maddyhome.idea.vim.vimscript.model.datatypes.asVimInt
+
+class HighLightVariable : Variable {
+
+  override fun evaluate(
+    name: String,
+    editor: VimEditor,
+    context: ExecutionContext,
+    vimContext: VimLContext,
+  ): VimDataType {
+    return injector.searchGroup.isSomeTextHighlighted().asVimInt()
+  }
+
+}

vim-engine/src/main/kotlin/com/maddyhome/idea/vim/vimscript/services/VimVariableServiceBase.kt

@@ -22,11 +22,11 @@ import com.maddyhome.idea.vim.vimscript.model.ExecutableContext
 import com.maddyhome.idea.vim.vimscript.model.VimLContext
 import com.maddyhome.idea.vim.vimscript.model.datatypes.VimDataType
 import com.maddyhome.idea.vim.vimscript.model.datatypes.VimInt
-import com.maddyhome.idea.vim.vimscript.model.datatypes.VimString
 import com.maddyhome.idea.vim.vimscript.model.expressions.Scope
 import com.maddyhome.idea.vim.vimscript.model.expressions.Variable
 import com.maddyhome.idea.vim.vimscript.model.statements.FunctionDeclaration
 import com.maddyhome.idea.vim.vimscript.model.statements.FunctionFlag
+import com.maddyhome.idea.vim.vimscript.model.variables.HighLightVariable
 import com.maddyhome.idea.vim.vimscript.model.variables.RegisterVariable
 
 abstract class VimVariableServiceBase : VariableService {
@@ -181,6 +181,9 @@ abstract class VimVariableServiceBase : VariableService {
       "count" -> VimInt(KeyHandler.getInstance().keyHandlerState.commandBuilder.calculateCount0Snapshot())
       "count1" -> VimInt(KeyHandler.getInstance().keyHandlerState.commandBuilder.calculateCount0Snapshot().coerceAtLeast(1))
       "searchforward" -> VimInt(if (injector.searchGroup.getLastSearchDirection() == Direction.FORWARDS) 1 else 0)
+      "hlsearch" -> {
+        HighLightVariable().evaluate(name, editor, context, vimContext)
+      }
       "register" -> {
          RegisterVariable().evaluate(name, editor, context, vimContext)
       }