1 files changed, 68 insertions, 0 deletions
diff --git a/spec/lib/banzai/filter/inline_diff_filter_spec.rb b/spec/lib/banzai/filter/inline_diff_filter_spec.rb
new file mode 100644
index 00000000000..9e526371294
--- /dev/null
+++ b/spec/lib/banzai/filter/inline_diff_filter_spec.rb
@@ -0,0 +1,68 @@
+require 'spec_helper'
+
+describe Banzai::Filter::InlineDiffFilter, lib: true do
+  include FilterSpecHelper
+
+  it 'adds inline diff span tags for deletions when using square brackets' do
+    doc = "START [-something deleted-] END"
+    expect(filter(doc).to_html).to eq('START <span class="idiff left right deletion">something deleted</span> END')
+  end
+
+  it 'adds inline diff span tags for deletions when using curley braces' do
+    doc = "START {-something deleted-} END"
+    expect(filter(doc).to_html).to eq('START <span class="idiff left right deletion">something deleted</span> END')
+  end
+
+  it 'does not add inline diff span tags when a closing tag is not provided' do
+    doc = "START [- END"
+    expect(filter(doc).to_html).to eq(doc)
+  end
+
+  it 'adds inline span tags for additions when using square brackets' do
+    doc = "START [+something added+] END"
+    expect(filter(doc).to_html).to eq('START <span class="idiff left right addition">something added</span> END')
+  end
+
+  it 'adds inline span tags for additions  when using curley braces' do
+    doc = "START {+something added+} END"
+    expect(filter(doc).to_html).to eq('START <span class="idiff left right addition">something added</span> END')
+  end
+
+  it 'does not add inline diff span tags when a closing addition tag is not provided' do
+    doc = "START {+ END"
+    expect(filter(doc).to_html).to eq(doc)
+  end
+
+  it 'does not add inline diff span tags when the tags do not match' do
+    examples = [
+      "{+ additions +]",
+      "[+ additions +}",
+      "{- delletions -]",
+      "[- delletions -}"
+    ]
+
+    examples.each do |doc|
+      expect(filter(doc).to_html).to eq(doc)
+    end
+  end
+
+  it 'prevents user-land html being injected' do
+    doc = "START {+&lt;script&gt;alert('I steal cookies')&lt;/script&gt;+} END"
+    expect(filter(doc).to_html).to eq("START <span class=\"idiff left right addition\">&lt;script&gt;alert('I steal cookies')&lt;/script&gt;</span> END")
+  end
+
+  it 'preserves content inside pre tags' do
+    doc = "<pre>START {+something added+} END</pre>"
+    expect(filter(doc).to_html).to eq(doc)
+  end
+
+  it 'preserves content inside code tags' do
+    doc = "<code>START {+something added+} END</code>"
+    expect(filter(doc).to_html).to eq(doc)
+  end
+
+  it 'preserves content inside tt tags' do
+    doc = "<tt>START {+something added+} END</tt>"
+    expect(filter(doc).to_html).to eq(doc)
+  end
+end