Bug 1913600 - Adjust drag'n'drop handling of compose window after bug 1851536. r=mkmelin

Since https://phabricator.services.mozilla.com/D193762 has landed, multiple selected contacts with display names that are dragged into the compose window are treated as attachments. This patch excludes dragged items containing the "text/x-moz-address" flavor from being checked for valid attachments and handles them directly.

Differential Revision: https://phabricator.services.mozilla.com/D222539

--HG--
extra : moz-landing-system : lando

mail/components/addrbook/test/browser/browser_drag_drop.js

@@ -84,6 +84,7 @@ async function doDragToComposeWindow(sourceIndices, expectedPills) {
   );
 
   cardsList.selectedIndices = sourceIndices;
+  const transitionPromise = BrowserTestUtils.waitForTransition(composeDocument);
   const [result, dataTransfer] = EventUtils.synthesizeDragOver(
     cardsList.getRowAtIndex(sourceIndices[0]),
     toAddrInput,
@@ -92,6 +93,13 @@ async function doDragToComposeWindow(sourceIndices, expectedPills) {
     abWindow,
     composeWindow
   );
+  await transitionPromise;
+  // Test that dragged contacts are not incorrectly recognized as attachments.
+  Assert.ok(
+    !composeDocument
+      .getElementById("dropAttachmentOverlay")
+      .classList.contains("show")
+  );
   EventUtils.synthesizeDropAfterDragOver(
     result,
     dataTransfer,

mail/components/compose/content/MsgComposeCommands.js

@@ -9895,12 +9895,10 @@ var envelopeDragObserver = {
    * attachments to handle the various drag&drop actions.
    *
    * @param {Event} event - The drag-and-drop event being performed.
-   * @param {boolean} isDropping - If the action was performed from the onDrop
-   *   method and it needs to handle pills creation.
    *
    * @returns {nsIMsgAttachment[]} - The array of valid attachments.
    */
-  getValidAttachments(event, isDropping) {
+  getValidAttachments(event) {
     const attachments = [];
     const dt = event.dataTransfer;
     const dataList = [];
@@ -10005,18 +10003,6 @@ var envelopeDragObserver = {
           );
           break;
         }
-        // Process address: Drop it into recipient field.
-        case "text/x-moz-address": {
-          // Process the drop only if the message body wasn't the target and we
-          // called this method from the onDrop() method.
-          if (event.target.baseURI != "about:blank?compose" && isDropping) {
-            DropRecipient(event.target, data);
-            // Prevent the default behaviour which drops the address text into
-            // the widget.
-            event.preventDefault();
-          }
-          break;
-        }
       }
 
       // Create the attachment and add it to attachments array.
@@ -10130,7 +10116,7 @@ var envelopeDragObserver = {
     // outcome of this drop action, but users can still copy and paste the image
     // in the editor to cirumvent this potential issue.
     const editor = GetCurrentEditor();
-    const attachments = this.getValidAttachments(event, true);
+    const attachments = this.getValidAttachments(event);
 
     for (const attachment of attachments) {
       if (!attachment?.url) {
@@ -10189,7 +10175,23 @@ var envelopeDragObserver = {
       return;
     }
 
-    const attachments = this.getValidAttachments(event, true);
+    // Handle address book entries directly, as they may also contain flavors
+    // that qualify as attachments.
+    if (event.dataTransfer.mozTypesAt(0).contains("text/x-moz-address")) {
+      if (event.target.baseURI != "about:blank?compose") {
+        // Process address: Drop it into recipient field.
+        DropRecipient(
+          event.target,
+          event.dataTransfer.mozGetDataAt("text/x-moz-address", 0)
+        );
+        // Prevent the default behaviour which drops the address text into
+        // the widget.
+        event.preventDefault();
+      }
+      return;
+    }
+
+    const attachments = this.getValidAttachments(event);
 
     // Interrupt if we don't have anything to attach.
     if (!attachments.length) {
@@ -10267,8 +10269,11 @@ var envelopeDragObserver = {
       this.detectHoveredOverlay(event.target.id);
       return;
     }
-
-    if (DROP_FLAVORS.some(f => event.dataTransfer.types.includes(f))) {
+    // Excluding dragged address book entries, check for valid attachments.
+    if (
+      !event.dataTransfer.mozTypesAt(0).contains("text/x-moz-address") &&
+      DROP_FLAVORS.some(f => event.dataTransfer.types.includes(f))
+    ) {
       // Show the drop overlay only if we dragged files or supported types.
       const attachments = this.getValidAttachments(event);
       if (attachments.length) {
@@ -10315,8 +10320,6 @@ var envelopeDragObserver = {
                 this.isNotDraggingOnlyImages(event.dataTransfer) ||
                 !gMsgCompose.composeHTML)
           );
-      } else {
-        DragAddressOverTargetControl(event);
       }
     }
 

mailnews/addrbook/content/abDragDrop.js

@@ -91,34 +91,3 @@ const abResultsPaneObserver = {
     event.stopPropagation();
   },
 };
-
-function DragAddressOverTargetControl() {
-  var dragSession = Cc["@mozilla.org/widget/dragservice;1"]
-    .getService(Ci.nsIDragService)
-    .getCurrentSession();
-
-  if (!dragSession.isDataFlavorSupported("text/x-moz-address")) {
-    return;
-  }
-
-  var trans = Cc["@mozilla.org/widget/transferable;1"].createInstance(
-    Ci.nsITransferable
-  );
-  trans.init(getLoadContext());
-  trans.addDataFlavor("text/x-moz-address");
-
-  var canDrop = true;
-
-  for (var i = 0; i < dragSession.numDropItems; ++i) {
-    dragSession.getData(trans, i);
-    var dataObj = {};
-    var bestFlavor = {};
-    try {
-      trans.getAnyTransferData(bestFlavor, dataObj);
-    } catch (ex) {
-      canDrop = false;
-      break;
-    }
-  }
-  dragSession.canDrop = canDrop;
-}