From fce6da505bc57ab6a842f737753633673808d4db Mon Sep 17 00:00:00 2001
From: Juanjo Diaz <juanjo.diazmo@gmail.com>
Date: Sun, 16 Oct 2022 12:10:44 +0200
Subject: [PATCH] Add check for clipboard permissions

---
 core/clipboard.js       | 43 ++++++++++++++++++++++++++++++++++-------
 tests/test.clipboard.js |  8 ++++----
 2 files changed, 40 insertions(+), 11 deletions(-)

diff --git a/core/clipboard.js b/core/clipboard.js
index a4a68132..29b2a356 100644
--- a/core/clipboard.js
+++ b/core/clipboard.js
@@ -14,18 +14,47 @@ export default class Clipboard {
 
     // ===== PRIVATE METHODS =====
 
-    _handleCopy(e) {
+    async _handleCopy(e) {
+        try {
+            if (navigator.permissions && navigator.permissions.query) {
+                const permission = await navigator.permissions.query({ name: "clipboard-write", allowWithoutGesture: false });
+                if (permission.state === 'denied') return;
+            }
+        } catch (err) {
+            // Some browsers might error due to lack of support, e.g. Firefox.
+        }
+
         if (navigator.clipboard.writeText) {
-            navigator.clipboard.writeText(e.clipboardData.getData('text/plain')).catch(() => {/* Do nothing */});
+            try {
+                await navigator.clipboard.writeText(e.clipboardData.getData('text/plain'));
+            } catch (e) {
+                /* Do nothing */
+            }
         }
     }
 
-    _handlePaste(e) {
-        if (navigator.clipboard.readText) {
-            navigator.clipboard.readText().then(this.onpaste).catch(() => {/* Do nothing */});
-        } else if (e.clipboardData) {
-            this.onpaste(e.clipboardData.getData('text/plain'));
+    async _handlePaste(e) {
+        try {
+            if (navigator.permissions && navigator.permissions.query) {
+                const permission = await navigator.permissions.query({ name: "clipboard-read", allowWithoutGesture: false });
+                if (permission.state === 'denied') return;
+            }
+        } catch (err) {
+            // Some browsers might error due to lack of support, e.g. Firefox.
         }
+
+        let data;
+        if (navigator.clipboard.readText) {
+            try {
+                data = await navigator.clipboard.readText();
+            } catch (e) {
+                /* Do nothing */
+                return;
+            }
+        } else if (e.clipboardData) {
+            data = e.clipboardData.getData('text/plain');
+        }
+        this.onpaste(data);
     }
 
     // ===== PUBLIC METHODS =====
diff --git a/tests/test.clipboard.js b/tests/test.clipboard.js
index 2ef00574..7b400e60 100644
--- a/tests/test.clipboard.js
+++ b/tests/test.clipboard.js
@@ -25,7 +25,7 @@ describe('Automatic Clipboard Sync', function () {
         });
     }
 
-    it('incoming clipboard data from the server is copied to the local clipboard', function () {
+    it('incoming clipboard data from the server is copied to the local clipboard', async function () {
         const text = 'Random string for testing';
         const clipboard = new Clipboard();
         if (Clipboard.isSupported) {
@@ -36,14 +36,14 @@ describe('Automatic Clipboard Sync', function () {
             if (!clipboardEvent.clipboardData.items.length) {
                 clipboardEvent.clipboardData.items.add(text, "text/plain");
             }
-            clipboard._handleCopy(clipboardEvent);
+            await clipboard._handleCopy(clipboardEvent);
             if (navigator.clipboard.writeText) {
                 expect(navigator.clipboard.writeText).to.have.been.calledWith(text);
             }
         }
     });
 
-    it('should copy local pasted data to the server clipboard', function () {
+    it('should copy local pasted data to the server clipboard', async function () {
         const text = 'Another random string for testing';
         const clipboard = new Clipboard();
         clipboard.onpaste = pasterText => expect(pasterText).to.equal(text);
@@ -55,7 +55,7 @@ describe('Automatic Clipboard Sync', function () {
             if (!clipboardEvent.clipboardData.items.length) {
                 clipboardEvent.clipboardData.items.add(text, "text/plain");
             }
-            clipboard._handlePaste(clipboardEvent);
+            await clipboard._handlePaste(clipboardEvent);
             if (navigator.clipboard.readText) {
                 expect(navigator.clipboard.readText).to.have.been.called;
             }