From 7628850800b3fbaf36255ee1eb991adcd74b94a8 Mon Sep 17 00:00:00 2001
From: Julia Silge <julia.silge@gmail.com>
Date: Thu, 25 Jun 2026 15:18:17 -0600
Subject: [PATCH] Hide the editor Preview button when Positron provides a
 native preview split button

---
 apps/vscode/package.json                  |  2 +-
 apps/vscode/src/providers/context-keys.ts | 26 +++++++++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/apps/vscode/package.json b/apps/vscode/package.json
index ac38b029..aedc831b 100644
--- a/apps/vscode/package.json
+++ b/apps/vscode/package.json
@@ -728,7 +728,7 @@
       "editor/title/run": [
         {
           "command": "quarto.preview",
-          "when": "editorLangId == quarto || editorLangId == markdown || activeCustomEditorId == 'quarto.visualEditor'"
+          "when": "(editorLangId == quarto || editorLangId == markdown || activeCustomEditorId == 'quarto.visualEditor') && !quartoCanUsePositronPreviewSplitButton"
         },
         {
           "command": "quarto.previewScript",
diff --git a/apps/vscode/src/providers/context-keys.ts b/apps/vscode/src/providers/context-keys.ts
index 665c5544..cdb27b11 100644
--- a/apps/vscode/src/providers/context-keys.ts
+++ b/apps/vscode/src/providers/context-keys.ts
@@ -15,6 +15,7 @@
 
 import * as vscode from "vscode";
 import debounce from "lodash.debounce";
+import { tryAcquirePositronApi } from "@posit-dev/positron";
 
 import { isQuartoDoc } from "../core/doc";
 import { MarkdownEngine } from "../markdown/engine";
@@ -44,6 +45,9 @@ export function activateContextKeySetter(
   setEditorContextKeys(vscode.window.activeTextEditor, engine);
   setLanguageContextKeys(vscode.window.activeTextEditor, engine);
 
+  // set the Positron preview split-button context key (static for the session)
+  setPositronPreviewSplitButtonContextKey();
+
   // register for quarto.render.renderOnSave or quarto.render.renderOnSaveShiny configuration change notification
   context.subscriptions.push(vscode.workspace.onDidChangeConfiguration(event => {
     // if the change affects quarto.render.renderOnSave or quarto.render.renderOnSaveShiny, set the editor context keys.
@@ -118,6 +122,28 @@ export function toggleRenderOnSaveOverride() {
   }
 }
 
+// Positron 2026.07.0+ provides a native Preview split button on the editor
+// action bar, with per-format preview in its dropdown. When running in such a
+// Positron, this context key lets us hide the extension's own `editor/title/run`
+// Preview button so there is a single button. Gating on the version (rather than
+// a Positron-set feature flag) keeps this temporal logic in the extension; the
+// check and key can be deleted once the supported Positron floor reaches that
+// version.
+//
+// String comparison, not `semver`: calendar versions like "2026.07.0" aren't
+// valid semver (leading zero in the month), but the zero-padded year/month sort
+// correctly lexicographically. This mirrors src/host/positron.ts.
+function setPositronPreviewSplitButtonContextKey() {
+  const positronVersion = tryAcquirePositronApi()?.version;
+  const canUsePositronPreviewSplitButton =
+    positronVersion !== undefined && positronVersion >= "2026.07.0";
+  vscode.commands.executeCommand(
+    "setContext",
+    "quartoCanUsePositronPreviewSplitButton",
+    canUsePositronPreviewSplitButton
+  );
+}
+
 // sets editor context keys
 function setEditorContextKeys(activeTextEditor: vscode.TextEditor | undefined, engine: MarkdownEngine) {
   // if a Quarto doc is active, set the editor context keys