4 files changed, 56 insertions, 5 deletions
diff --git a/app/views/projects/diffs/_email_line.html.haml b/app/views/projects/diffs/_email_line.html.haml
new file mode 100644
index 00000000000..dfff143196c
--- /dev/null
+++ b/app/views/projects/diffs/_email_line.html.haml
@@ -0,0 +1,21 @@
+-# This template is used when rendering diffs in email notifications
+-# Called inside: app/views/notify/repository_push_email.html.haml
+-#                app/views/notify/_note_email.html.haml
+
+%tr.line_holder{ class: line.type }
+  - case line.type
+  - when 'match'
+    = diff_match_line line.old_pos, line.new_pos, text: line.text
+  - when 'old-nonewline', 'new-nonewline'
+    %td.old_line.diff-line-num
+    %td.new_line.diff-line-num
+    %td.line_content.match= line.text
+  - else
+    %td.old_line.diff-line-num{ class: line.type, data: { linenumber: line.old_pos } }
+      = diff_link_number(line.type, "new", line.old_pos)
+
+    %td.new_line.diff-line-num{ class: line.type, data: { linenumber: line.new_pos } }
+      = diff_link_number(line.type, "old", line.new_pos)
+
+    %td.line_content{ class: line.type }<
+      %pre= line.rich_text
diff --git a/app/views/projects/diffs/_file_header.html.haml b/app/views/projects/diffs/_file_header.html.haml
index d1792826522..afca27c5430 100644
--- a/app/views/projects/diffs/_file_header.html.haml
+++ b/app/views/projects/diffs/_file_header.html.haml
@@ -36,5 +36,5 @@
       #{diff_file.a_mode} → #{diff_file.b_mode}
 
   - if diff_file.stored_externally? && diff_file.external_storage == :lfs
-    %span.badge.label-lfs.gl-mr-2 LFS
+    = gl_badge_tag(_('LFS'), variant: :neutral)
 
diff --git a/app/views/projects/diffs/_line.html.haml b/app/views/projects/diffs/_line.html.haml
index de7f9eba158..330e2f564c9 100644
--- a/app/views/projects/diffs/_line.html.haml
+++ b/app/views/projects/diffs/_line.html.haml
@@ -1,3 +1,5 @@
+-# This file is deprecated in favour of inline rendering:
+-# https://gitlab.com/gitlab-org/gitlab/-/merge_requests/57237
 - plain = local_assigns.fetch(:plain, false)
 - discussions = local_assigns.fetch(:discussions, nil)
 - line_code = diff_file.line_code(line)
diff --git a/app/views/projects/diffs/_text_file.html.haml b/app/views/projects/diffs/_text_file.html.haml
index bf946b0ce73..6e7e0244721 100644
--- a/app/views/projects/diffs/_text_file.html.haml
+++ b/app/views/projects/diffs/_text_file.html.haml
@@ -4,10 +4,38 @@
     %a.show-suppressed-diff.cursor-pointer.js-show-suppressed-diff= _("Changes suppressed. Click to show.")
 
 %table.text-file.diff-wrap-lines.code.code-commit.js-syntax-highlight.commit-diff{ data: diff_view_data, class: too_big ? 'hide' : '' }
-  = render partial: "projects/diffs/line",
-    collection: diff_file.highlighted_diff_lines,
-    as: :line,
-    locals: { diff_file: diff_file, discussions: @grouped_diff_discussions }
+  - if Feature.enabled?(:inline_haml_diff_line_rendering, @project, default_enabled: :yaml)
+    - diff_file.highlighted_diff_lines.each do |line|
+      - line_code = diff_file.line_code(line)
+
+      %tr.line_holder{ class: line.type, id: line_code }
+        - case line.type
+        - when 'match'
+          = diff_match_line line.old_pos, line.new_pos, text: line.text
+        - when 'old-nonewline', 'new-nonewline'
+          %td.old_line.diff-line-num
+          %td.new_line.diff-line-num
+          %td.line_content.match= line.text
+        - else
+          %td.old_line.diff-line-num{ class: "#{line.type} js-avatar-container", data: { linenumber: line.old_pos } }
+            = add_diff_note_button(line_code, diff_file.position(line), line.type)
+            %a{ href: "##{line_code}", data: { linenumber: diff_link_number(line.type, "new", line.old_pos) } }
+
+          %td.new_line.diff-line-num{ class: line.type, data: { linenumber: line.new_pos } }
+            %a{ href: "##{line_code}", data: { linenumber: diff_link_number(line.type, "old", line.new_pos) } }
+
+          %td.line_content{ class: line.type }<
+            = diff_line_content(line.rich_text)
+
+      - if line.discussable? && @grouped_diff_discussions.present? && @grouped_diff_discussions[line_code]
+        - line_discussions = @grouped_diff_discussions[line_code]
+        = render "discussions/diff_discussion", discussions: line_discussions, expanded: line_discussions.any?(&:expanded?)
+
+  - else
+    = render partial: "projects/diffs/line",
+      collection: diff_file.highlighted_diff_lines,
+      as: :line,
+      locals: { diff_file: diff_file, discussions: @grouped_diff_discussions }
 
   - if !diff_file.new_file? && !diff_file.deleted_file? && diff_file.highlighted_diff_lines.any?
     - last_line = diff_file.highlighted_diff_lines.last