From 9e4552d7920fcba13b3d74e1e180fc49180f4436 Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Thu, 3 Oct 2019 12:03:45 +0200
Subject: [PATCH] [PDFSidebarResizer] Refactor the clamping in `_updateWidth`

Rather than manually clamping the `width` here, we can just `export` an already existing helper function from `ui_utils.js` instead.

(Hopefully it will eventually be possible to replace this helper function with a native `Math.clamp` function, given that there exists a "Stage 1 Proposal" for adding such a thing to the ECMAScript specification.)
---
 web/pdf_sidebar_resizer.js | 17 ++++++-----------
 web/ui_utils.js            |  1 +
 2 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/web/pdf_sidebar_resizer.js b/web/pdf_sidebar_resizer.js
index 388331054..f975c0587 100644
--- a/web/pdf_sidebar_resizer.js
+++ b/web/pdf_sidebar_resizer.js
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-import { NullL10n } from './ui_utils';
+import { clamp, NullL10n } from './ui_utils';
 
 const SIDEBAR_WIDTH_VAR = '--sidebar-width';
 const SIDEBAR_MIN_WIDTH = 200; // pixels
@@ -84,19 +84,14 @@ class PDFSidebarResizer {
     }
     // Prevent the sidebar from becoming too narrow, or from occupying more
     // than half of the available viewer width.
-    const maxWidth = Math.floor(this.outerContainerWidth / 2);
-    if (width > maxWidth) {
-      width = maxWidth;
-    }
-    if (width < SIDEBAR_MIN_WIDTH) {
-      width = SIDEBAR_MIN_WIDTH;
-    }
+    const newWidth = clamp(width, SIDEBAR_MIN_WIDTH,
+                           Math.floor(this.outerContainerWidth / 2));
     // Only update the UI when the sidebar width did in fact change.
-    if (width === this._width) {
+    if (newWidth === this._width) {
       return false;
     }
-    this._width = width;
-    this.doc.style.setProperty(SIDEBAR_WIDTH_VAR, `${width}px`);
+    this._width = newWidth;
+    this.doc.style.setProperty(SIDEBAR_WIDTH_VAR, `${newWidth}px`);
     return true;
   }
 
diff --git a/web/ui_utils.js b/web/ui_utils.js
index e1235759a..cb7108a75 100644
--- a/web/ui_utils.js
+++ b/web/ui_utils.js
@@ -898,6 +898,7 @@ export {
   NullL10n,
   EventBus,
   getGlobalEventBus,
+  clamp,
   ProgressBar,
   getPDFFileNameFromURL,
   noContextMenuHandler,