Extract and use FrameElement.getElementById

Unify the query selector construction and retrieval logic to:

* find elements matching `turbo-frame`
* find elements with a matching `[id]` attribute that are not `_top`
* omit elements that declare `[disabled]`

src/core/frames/frame_controller.ts

@@ -213,7 +213,7 @@ export class FrameController implements AppearanceObserverDelegate, FetchRequest
 
   private findFrameElement(element: Element) {
     const id = element.getAttribute("data-turbo-frame") || this.element.getAttribute("target")
-    return getFrameElementById(id) ?? this.element
+    return FrameElement.getElementById(document, id) ?? this.element
   }
 
   async extractForeignFrameElement(container: ParentNode): Promise<FrameElement> {
@@ -238,16 +238,11 @@ export class FrameController implements AppearanceObserverDelegate, FetchRequest
 
     if (!this.enabled || id == "_top") {
       return false
+    } else if (id) {
+      return !!FrameElement.getElementById(document, id)
+    } else {
+      return true
     }
-
-    if (id) {
-      const frameElement = getFrameElementById(id)
-      if (frameElement) {
-        return !frameElement.disabled
-      }
-    }
-
-    return true
   }
 
   // Computed properties
@@ -277,15 +272,6 @@ export class FrameController implements AppearanceObserverDelegate, FetchRequest
   }
 }
 
-function getFrameElementById(id: string | null) {
-  if (id != null) {
-    const element = document.getElementById(id)
-    if (element instanceof FrameElement) {
-      return element
-    }
-  }
-}
-
 function activateElement(element: Node | null) {
   if (element && element.ownerDocument !== document) {
     element = document.importNode(element, true)

src/core/frames/frame_redirector.ts

@@ -51,12 +51,6 @@ export class FrameRedirector implements LinkInterceptorDelegate, FormInterceptor
   }
 
   private findFrameElement(element: Element) {
-    const id = element.getAttribute("data-turbo-frame")
-    if (id && id != "_top") {
-      const frame = this.element.querySelector(`#${id}:not([disabled])`)
-      if (frame instanceof FrameElement) {
-        return frame
-      }
-    }
+    return FrameElement.getElementById(this.element, element.getAttribute("data-turbo-frame"))
   }
 }

src/elements/frame_element.ts

@@ -23,6 +23,15 @@ export class FrameElement extends HTMLElement {
     return ["loading", "src"]
   }
 
+  static getElementById(container: Element | Document, id: string | null): FrameElement | undefined {
+    if (id && id != "_top") {
+      const frame = container.querySelector(`#${id}:not([disabled])`)
+      if (frame instanceof FrameElement) {
+        return frame
+      }
+    }
+  }
+
   constructor() {
     super()
     this.delegate = new FrameElement.delegateConstructor(this)