(core) Include linking rowIds into remembered cursor position and anchor links.

Summary:
When linking using a Reference List column, there may be multiple source
records that show the same target record. With this change, we remember those
(rather than just pick one that shows the target record).

Test Plan: Added a browser test.

Reviewers: jarek

Reviewed By: jarek

Differential Revision: https://phab.getgrist.com/D4140

app/client/components/BaseView.js

@@ -395,7 +395,8 @@ BaseView.prototype.getAnchorLinkForSection = function(sectionId) {
   const fieldIndex = this.cursor.fieldIndex.peek();
   const field = fieldIndex !== null ? this.viewSection.viewFields().peek()[fieldIndex] : null;
   const colRef = field?.colRef.peek();
-  return {hash: {sectionId, rowId, colRef}};
+  const linkingRowIds = sectionId ? this.gristDoc.getLinkingRowIds(sectionId) : undefined;
+  return {hash: {sectionId, rowId, colRef, linkingRowIds}};
 }
 
 // Copy an anchor link for the current row to the clipboard.

app/client/components/CursorMonitor.ts

@@ -59,7 +59,12 @@ export class CursorMonitor extends Disposable {
       if (!this._restored) { return; }
       // store position only when we have valid rowId
       // for some views (like CustomView) cursor position might not reflect actual row
-      if (pos && pos.rowId !== undefined) { this._storePosition(pos); }
+      if (pos && pos.rowId !== undefined) {
+        if (pos.sectionId) {
+          pos = {...pos, linkingRowIds: doc.getLinkingRowIds(pos.sectionId)};
+        }
+        this._storePosition(pos);
+      }
     }));
   }
 

app/client/components/GristDoc.ts

@@ -72,7 +72,7 @@ import {TableData} from 'app/common/TableData';
 import {getGristConfig} from 'app/common/urlUtils';
 import {DocStateComparison} from 'app/common/UserAPI';
 import {AttachedCustomWidgets, IAttachedCustomWidget, IWidgetType} from 'app/common/widgetTypes';
-import {CursorPos} from 'app/plugin/GristAPI';
+import {CursorPos, UIRowId} from 'app/plugin/GristAPI';
 import {
   bundleChanges,
   Computed,
@@ -1181,6 +1181,29 @@ export class GristDoc extends DisposableWithEvents {
     return rulesTable.numRecords() > rulesTable.filterRowIds({permissionsText: '', permissions: 63}).length;
   }
 
+  /**
+   * If the given section is the target of linking, collect and return the active rowIDs up the
+   * chain of links, returning the list of rowIds starting with the current section's parent. This
+   * method is intended for when there is ambiguity such as when RefList linking is involved.
+   * In other cases, returns undefined.
+   */
+  public getLinkingRowIds(sectionId: number): UIRowId[]|undefined {
+    const linkingRowIds: UIRowId[] = [];
+    let anyAmbiguity = false;
+    let section = this.docModel.viewSections.getRowModel(sectionId);
+    const seen = new Set<number>();
+    while (section?.id.peek() && !seen.has(section.id.peek())) {
+      seen.add(section.id.peek());
+      const rowId = section.activeRowId.peek() || 'new';
+      if (isRefListType(section.linkTargetCol.peek().type.peek()) || rowId === 'new') {
+        anyAmbiguity = true;
+      }
+      linkingRowIds.push(rowId);
+      section = section.linkSrcSection.peek();
+    }
+    return anyAmbiguity ? linkingRowIds.slice(1) : undefined;
+  }
+
   /**
    * Move to the desired cursor position.  If colRef is supplied, the cursor will be
    * moved to a field with that colRef.  Any linked sections that need their cursors
@@ -1211,6 +1234,8 @@ export class GristDoc extends DisposableWithEvents {
       }
 
       const srcSection = section.linkSrcSection.peek();
+      const linkingRowId = cursorPos.linkingRowIds?.[0];
+      const linkingRowIds = cursorPos.linkingRowIds?.slice(1);
       if (srcSection.id.peek()) {
         // We're in a linked section, so we need to recurse to make sure the row we want
         // will be visible.
@@ -1218,7 +1243,11 @@ export class GristDoc extends DisposableWithEvents {
         let controller: any;
         if (linkTargetCol.colId.peek()) {
           const destTable = await this._getTableData(section);
-          controller = destTable.getValue(cursorPos.rowId, linkTargetCol.colId.peek());
+          if (cursorPos.rowId === 'new') {
+            controller = 'new';
+          } else {
+            controller = destTable.getValue(cursorPos.rowId, linkTargetCol.colId.peek());
+          }
         } else {
           controller = cursorPos.rowId;
         }
@@ -1228,8 +1257,15 @@ export class GristDoc extends DisposableWithEvents {
         if (!colId && !isSrcSummary) {
           // Simple case - source linked by rowId, not a summary.
           if (isList(controller)) {
-            // Should be a reference list. Pick the first reference.
-            controller = controller[1];  // [0] is the L type code, [1] is the first value
+            // Should be a reference list. Use linkingRowId if available and present in the list,
+            if (linkingRowId && controller.indexOf(linkingRowId) > 0) {
+              controller = linkingRowId;
+            } else {
+              // Otherwise, pick the first reference.
+              controller = controller[1];  // [0] is the L type code, [1] is the first value
+            }
+          } else if (controller === 'new' && linkingRowId) {
+            controller = linkingRowId;
           }
           srcRowId = controller;
         } else {
@@ -1253,12 +1289,13 @@ export class GristDoc extends DisposableWithEvents {
           }
           srcRowId = srcTable.getRowIds().find(getFilterFunc(this.docData, query));
         }
-        if (!srcRowId || typeof srcRowId !== 'number') {
+        if (!srcRowId || (typeof srcRowId !== 'number' && srcRowId !== 'new')) {
           throw new Error('cannot trace rowId');
         }
         await this.recursiveMoveToCursorPos({
           rowId: srcRowId,
           sectionId: srcSection.id.peek(),
+          linkingRowIds,
         }, false, silent, visitedSections.concat([section.id.peek()]));
       }
       const view: ViewRec = section.view.peek();
@@ -1694,6 +1731,7 @@ export class GristDoc extends DisposableWithEvents {
       if (fieldIndex >= 0) {
         cursorPos.fieldIndex = fieldIndex;
       }
+      cursorPos.linkingRowIds = hash.linkingRowIds;
     }
     return cursorPos;
   }