1 files changed, 73 insertions, 0 deletions
diff --git a/app/components/diffs/overflow_warning_component.rb b/app/components/diffs/overflow_warning_component.rb
new file mode 100644
index 00000000000..0d0e225beb4
--- /dev/null
+++ b/app/components/diffs/overflow_warning_component.rb
@@ -0,0 +1,73 @@
+# frozen_string_literal: true
+
+module Diffs
+  class OverflowWarningComponent < BaseComponent
+    # Skipping coverage because of https://gitlab.com/gitlab-org/gitlab/-/issues/357381
+    #
+    # This is fully tested by the output in the view part of this component,
+    # but undercoverage doesn't understand the relationship between the two parts.
+    #
+    # :nocov:
+    def initialize(diffs:, diff_files:, project:, commit: nil, merge_request: nil)
+      @diffs = diffs
+      @diff_files = diff_files
+      @project = project
+      @commit = commit
+      @merge_request = merge_request
+    end
+
+    def message
+      html_escape(message_text) % {
+        display_size: @diff_files.size,
+        real_size: @diffs.real_size,
+        strong_open: '<strong>'.html_safe,
+        strong_close: '</strong>'.html_safe
+      }
+    end
+
+    def diff_link
+      text = _("Plain diff")
+
+      if commit?
+        link_to text, project_commit_path(@project, @commit, format: :diff), class: button_classes
+      elsif merge_request?
+        link_to text, merge_request_path(@merge_request, format: :diff), class: button_classes
+      end
+    end
+
+    def patch_link
+      text = _("Email patch")
+
+      if commit?
+        link_to text, project_commit_path(@project, @commit, format: :patch), class: button_classes
+      elsif merge_request?
+        link_to text, merge_request_path(@merge_request, format: :patch), class: button_classes
+      end
+    end
+
+    private
+
+    def commit?
+      current_controller?(:commit) &&
+        @commit.present?
+    end
+
+    def merge_request?
+      current_controller?("projects/merge_requests/diffs") &&
+        @merge_request.present? &&
+        @merge_request.persisted?
+    end
+
+    def message_text
+      _(
+        "To preserve performance only %{strong_open}%{display_size} " \
+        "of %{real_size}%{strong_close} files are displayed."
+      )
+    end
+
+    def button_classes
+      "btn gl-alert-action btn-default gl-button btn-default-secondary"
+    end
+    # :nocov:
+  end
+end