From bc8739f017192a88156d2a7983c2b3d1632b23a6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tobias=20Ho=CC=88=C3=9Fl?= <tobias@hoessl.eu>
Date: Sat, 27 Apr 2019 17:49:21 +0200
Subject: [PATCH] Diff-Bugfix: Insertions/Deletions beyond paragraph boundaries

---
 .../app/core/ui-services/diff.service.spec.ts | 16 ++++++
 .../src/app/core/ui-services/diff.service.ts  | 56 ++++++++++++++++---
 2 files changed, 64 insertions(+), 8 deletions(-)

diff --git a/client/src/app/core/ui-services/diff.service.spec.ts b/client/src/app/core/ui-services/diff.service.spec.ts
index 48a0e4bcc..186f007d8 100644
--- a/client/src/app/core/ui-services/diff.service.spec.ts
+++ b/client/src/app/core/ui-services/diff.service.spec.ts
@@ -886,6 +886,22 @@ describe('DiffService', () => {
             }
         ));
 
+        it('detects inline insertions exceeding block paragraphs', inject([DiffService], (service: DiffService) => {
+            const before =
+                    '<P>Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua.</P>\n' +
+                    '<P>At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.</P>',
+                after =
+                    '<P>Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. Insertion 1</P>\n' +
+                    '<P>Insertion 2 At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.</P>';
+
+            const diff = service.diff(before, after);
+
+            expect(diff).toBe(
+                '<p>Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua.<ins> Insertion 1</ins></p>\n' +
+                    '<p><ins>Insertion 2 </ins>At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.</p>'
+            );
+        }));
+
         it('does not lose formattings when multiple lines are deleted', inject(
             [DiffService],
             (service: DiffService) => {
diff --git a/client/src/app/core/ui-services/diff.service.ts b/client/src/app/core/ui-services/diff.service.ts
index f565fd2f7..1cc637550 100644
--- a/client/src/app/core/ui-services/diff.service.ts
+++ b/client/src/app/core/ui-services/diff.service.ts
@@ -2001,14 +2001,6 @@ export class DiffService {
             }
         );
 
-        // <del>deleted text</P></del><ins>inserted.</P></ins> => <del>deleted tet</del><ins>inserted.</ins></P>
-        diffUnnormalized = diffUnnormalized.replace(
-            /<del>([^<]*)<\/(p|div|blockquote|li)><\/del><ins>([^<]*)<\/\2><\/ins>\s*$/gi,
-            (whole: string, deleted: string, tag: string, inserted: string): string => {
-                return '<del>' + deleted + '</del><ins>' + inserted + '</ins></' + tag + '>';
-            }
-        );
-
         // If larger inserted HTML text contains block elements, we separate the inserted text into
         // inline <ins> elements and "insert"-class-based block elements.
         // <ins>...<div>...</div>...</ins> => <ins>...</ins><div class="insert">...</div><ins>...</ins>
@@ -2026,6 +2018,54 @@ export class DiffService {
             }
         );
 
+        // <del>deleted text</P></del><ins>inserted.</P></ins> => <del>deleted tet</del><ins>inserted.</ins></P>
+        diffUnnormalized = diffUnnormalized.replace(
+            /<del>([^<]*)<\/(p|div|blockquote|li)><\/del><ins>([^<]*)<\/\2>(\s*)<\/ins>/gi,
+            (whole: string, deleted: string, tag: string, inserted: string, white: string): string => {
+                return '<del>' + deleted + '</del><ins>' + inserted + '</ins></' + tag + '>' + white;
+            }
+        );
+
+        // <ins>...</p><p>...</ins> => <ins>...</ins></p><p><ins>...</ins>
+        diffUnnormalized = diffUnnormalized.replace(
+            /<(ins|del)>([\s\S]*?)<\/(p|div|blockquote|li)>\s*<(p|div|blockquote|li)([^>]*)>([\s\S]*?)<\/\1>/gi,
+            (
+                whole: string,
+                insDel: string,
+                content1: string,
+                blockEnd: string,
+                blockStart: string,
+                blockAttrs: string,
+                content2: string
+            ): string => {
+                if (this.isValidInlineHtml(content1) && this.isValidInlineHtml(content2)) {
+                    return (
+                        '<' +
+                        insDel +
+                        '>' +
+                        content1 +
+                        '</' +
+                        insDel +
+                        '></' +
+                        blockEnd +
+                        '>' +
+                        '<' +
+                        blockStart +
+                        blockAttrs +
+                        '><' +
+                        insDel +
+                        '>' +
+                        content2 +
+                        '</' +
+                        insDel +
+                        '>'
+                    );
+                } else {
+                    return whole;
+                }
+            }
+        );
+
         // Cleanup leftovers from the operation above, when <ins></ins>-tags ore <ins> </ins>-tags are left
         // around block tags. It should be safe to remove them and just leave the whitespaces.
         diffUnnormalized = diffUnnormalized.replace(