fix(Unidirectional|Merge): Use lower similarity threshold for folder similarity

fixes #2230

Signed-off-by: Marcel Klehr <mklehr@gmx.net>

Author: marcelklehr

src/lib/Scanner.ts

@@ -182,7 +182,7 @@ export default class Scanner<L1 extends TItemLocation, L2 extends TItemLocation>
             this.mergeable(removedItem, createdItem) &&
             (removedItem.type !== 'folder' ||
               (!this.hasCache &&
-                removedItem.childrenSimilarity(createdItem) > 0.8))
+                removedItem.childrenSimilarity(createdItem) >= 0.5))
           ) {
             this.result.CREATE.retract(createAction)
             this.result.REMOVE.retract(removeAction)

src/test/test.js

@@ -2103,6 +2103,143 @@ describe('Floccus', function() {
               false
             )
           })
+          it('should move items without confusing folders (2)', async function() {
+            const localRoot = account.getData().localRoot
+
+            const folder1 = await browser.bookmarks.create({
+              title: 'a',
+              parentId: localRoot
+            })
+            const folder2 = await browser.bookmarks.create({
+              title: 'b',
+              parentId: folder1.id
+            })
+            const folder3 = await browser.bookmarks.create({
+              title: 'c',
+              parentId: folder2.id
+            })
+            const folder4 = await browser.bookmarks.create({
+              title: 'd',
+              parentId: localRoot
+            })
+            const folder5 = await browser.bookmarks.create({
+              title: 'e',
+              parentId: folder4.id,
+            })
+            const folder6 = await browser.bookmarks.create({
+              title: 'f',
+              parentId: folder5.id,
+            })
+            const folderX = await browser.bookmarks.create({
+              title: 'X',
+              parentId: folder3.id,
+            })
+            await browser.bookmarks.create({
+              title: 'url',
+              url: 'http://ur.l/',
+              parentId: folderX.id
+            })
+            const folderX2 = await browser.bookmarks.create({
+              title: 'X',
+              parentId: folder6.id,
+            })
+            await browser.bookmarks.create({
+              title: 'test',
+              url: 'http://urrr.l/',
+              parentId: folderX2.id
+            })
+            const test2Bm = await browser.bookmarks.create({
+              title: 'test2',
+              url: 'http://urrr2.l/',
+              parentId: folder1.id
+            })
+
+            await account.sync() // propagate to server
+            expect(account.getData().error).to.not.be.ok
+
+            await account.sync() // make sure order is propagated
+            expect(account.getData().error).to.not.be.ok
+
+            await account.init() // Remove the cache
+
+            await browser.bookmarks.move(folderX.id, { parentId: folder2.id })
+            await browser.bookmarks.move(folderX2.id, { parentId: folder5.id })
+            await browser.bookmarks.move(test2Bm.id, { parentId: folderX.id })
+
+            await account.sync() // propagate to server
+            expect(account.getData().error).to.not.be.ok
+
+            const tree = await getAllBookmarks(account)
+            expectTreeEqual(
+              tree,
+              new Folder({
+                title: tree.title,
+                children: [
+                  new Folder({
+                    title: 'a',
+                    children: [
+                      new Folder({
+                        title: 'b',
+                        children: [
+                          new Folder({
+                            title: 'c',
+                            children: [],
+                          }),
+                          new Folder({
+                            title: 'X',
+                            children: [
+                              new Bookmark({
+                                title: 'url',
+                                url: 'http://ur.l/',
+                              }),
+                              new Bookmark({
+                                title: 'test2',
+                                url: 'http://urrr2.l/',
+                              }),
+                            ],
+                          }),
+                        ],
+                      }),
+                    ],
+                  }),
+                  new Folder({
+                    title: 'd',
+                    children: [
+                      new Folder({
+                        title: 'e',
+                        children: [
+                          new Folder({
+                            title: 'f',
+                            children: [],
+                          }),
+                          new Folder({
+                            title: 'X',
+                            children: [
+                              new Bookmark({
+                                title: 'test',
+                                url: 'http://urrr.l/',
+                              }),
+                            ],
+                          }),
+                        ],
+                      }),
+                    ],
+                  }),
+                ],
+              }),
+              false,
+              false
+            )
+
+            const localTree = await account.localTree.getBookmarksTree(true)
+            localTree.title = tree.title
+            expectTreeEqual(
+              localTree,
+              tree,
+              false,
+              false
+            )
+          })
           it('should integrate existing items from both sides', async function() {
             const localRoot = account.getData().localRoot