Revisit element picker arguments code

No need to store mouse coordinates in background
page, thus no need to post mouse coordinates
information for every click.

Rename/group element picker arguments and popup
arguments separately.

src/js/background.js

@@ -174,16 +174,17 @@ const µBlock = (function() { // jshint ignore:line
 
         apiErrorCount: 0,
 
-        mouseEventRegister: {
-            tabId: '',
-            x: -1,
-            y: -1,
-            url: ''
+        maybeGoodPopup: {
+            tabId: 0,
+            url: '',
         },
 
-        epickerTarget: '',
-        epickerZap: false,
-        epickerEprom: null,
+        epickerArgs: {
+            eprom: null,
+            mouse: false,
+            target: '',
+            zap: false,
+        },
 
         scriptlets: {},
 

src/js/commands.js

@@ -136,7 +136,7 @@ vAPI.commands.onCommand.addListener(async command => {
     case 'launch-element-zapper': {
         const tab = await vAPI.tabs.getCurrent();
         if ( tab instanceof Object === false ) { return; }
-        µb.mouseEventRegister.x = µb.mouseEventRegister.y = -1;
+        µb.epickerArgs.mouse = false;
         µb.elementPickerExec(
             tab.id,
             undefined,

src/js/contentscript.js

@@ -1417,23 +1417,25 @@ vAPI.bootstrap = (function() {
             return;
         }
 
-        // To send mouse coordinates to main process, as the chrome API fails
-        // to provide the mouse position to context menu listeners.
-        // https://github.com/chrisaljoudi/uBlock/issues/1143
-        // Also, find a link under the mouse, to try to avoid confusing new tabs
-        // as nuisance popups.
-        // Ref.: https://developer.mozilla.org/en-US/docs/Web/Events/contextmenu
+        // To be used by element picker/zapper.
+        vAPI.mouseClick = { x: -1, y: -1 };
 
         const onMouseClick = function(ev) {
+            if ( ev.isTrusted === false ) { return; }
+            vAPI.mouseClick.x = ev.clientX;
+            vAPI.mouseClick.y = ev.clientY;
+
+            // https://github.com/chrisaljoudi/uBlock/issues/1143
+            //   Find a link under the mouse, to try to avoid confusing new tabs
+            //   as nuisance popups.
             let elem = ev.target;
             while ( elem !== null && elem.localName !== 'a' ) {
                 elem = elem.parentElement;
             }
+            if ( elem === null ) { return; }
             vAPI.messaging.send('contentscript', {
-                what: 'mouseClick',
-                x: ev.clientX,
-                y: ev.clientY,
-                url: elem !== null && ev.isTrusted !== false ? elem.href : '',
+                what: 'maybeGoodPopup',
+                url: elem.href || '',
             });
         };
 

src/js/contextmenu.js

@@ -57,6 +57,7 @@ const onBlockElement = function(details, tab) {
         }
     }
 
+    µBlock.epickerArgs.mouse = true;
     µBlock.elementPickerExec(tab.id, tagName + '\t' + src);
 };
 

src/js/messaging.js

@@ -129,7 +129,7 @@ const onMessage = function(request, sender, callback) {
 
     case 'launchElementPicker':
         // Launched from some auxiliary pages, clear context menu coords.
-        µb.mouseEventRegister.x = µb.mouseEventRegister.y = -1;
+        µb.epickerArgs.mouse = false;
         µb.elementPickerExec(request.tabId, request.targetURL, request.zap);
         break;
 
@@ -539,11 +539,9 @@ const onMessage = function(request, sender, callback) {
         }
         break;
 
-    case 'mouseClick':
-        µb.mouseEventRegister.tabId = tabId;
-        µb.mouseEventRegister.x = request.x;
-        µb.mouseEventRegister.y = request.y;
-        µb.mouseEventRegister.url = request.url;
+    case 'maybeGoodPopup':
+        µb.maybeGoodPopup.tabId = tabId;
+        µb.maybeGoodPopup.url = request.url;
         break;
 
     case 'shouldRenderNoscriptTags':
@@ -669,15 +667,13 @@ const onMessage = function(request, sender, callback) {
 
             callback({
                 frameContent: this.responseText.replace(reStrings, replacer),
-                target: µb.epickerTarget,
-                clientX: µb.mouseEventRegister.x,
-                clientY: µb.mouseEventRegister.y,
-                zap: µb.epickerZap,
-                eprom: µb.epickerEprom
+                target: µb.epickerArgs.target,
+                mouse: µb.epickerArgs.mouse,
+                zap: µb.epickerArgs.zap,
+                eprom: µb.epickerArgs.eprom,
             });
 
-            µb.epickerTarget = '';
-            µb.mouseEventRegister.x = µb.mouseEventRegister.y = -1;
+            µb.epickerArgs.target = '';
         };
         xhr.send();
         return;
@@ -703,7 +699,7 @@ const onMessage = function(request, sender, callback) {
         break;
 
     case 'elementPickerEprom':
-        µb.epickerEprom = request;
+        µb.epickerArgs.eprom = request;
         break;
 
     default:

src/js/scriptlets/element-picker.js

@@ -1636,8 +1636,12 @@ const startPicker = function(details) {
     highlightElements([], true);
 
     // Try using mouse position
-    if ( details.clientX !== -1 ) {
-        if ( filtersFrom(details.clientX, details.clientY) !== 0 ) {
+    if (
+        details.mouse &&
+        typeof vAPI.mouseClick.x === 'number' &&
+        vAPI.mouseClick.x > 0
+    ) {
+        if ( filtersFrom(vAPI.mouseClick.x, vAPI.mouseClick.y) !== 0 ) {
             showDialog();
             return;
         }

src/js/tab.js

@@ -437,8 +437,8 @@ housekeep itself.
             this.opener = {
                 tabId: openerTabId,
                 popunder: false,
-                trustedURL: openerTabId === µb.mouseEventRegister.tabId
-                    ? µb.mouseEventRegister.url
+                trustedURL: openerTabId === µb.maybeGoodPopup.tabId
+                    ? µb.maybeGoodPopup.url
                     : ''
             };
             this.selfDestructionTimer = null;

src/js/ublock.js

@@ -414,22 +414,22 @@ const matchBucket = function(url, hostname, bucket, start) {
 
 /******************************************************************************/
 
-µBlock.elementPickerExec = async function(tabId, targetElement, zap) {
+µBlock.elementPickerExec = async function(tabId, targetElement, zap = false) {
     if ( vAPI.isBehindTheSceneTabId(tabId) ) { return; }
 
-    this.epickerTarget = targetElement || '';
-    this.epickerZap = zap || false;
+    this.epickerArgs.target = targetElement || '';
+    this.epickerArgs.zap = zap;
 
     // https://github.com/uBlockOrigin/uBlock-issues/issues/40
     //   The element picker needs this library
     vAPI.tabs.executeScript(tabId, {
         file: '/lib/diff/swatinem_diff.js',
-        runAt: 'document_end'
+        runAt: 'document_end',
     });
 
     await vAPI.tabs.executeScript(tabId, {
         file: '/js/scriptlets/element-picker.js',
-        runAt: 'document_end'
+        runAt: 'document_end',
     });
 
     // https://github.com/uBlockOrigin/uBlock-issues/issues/168