Python difflib for string diffs

string_diff_using_difflib.py

# Using python difflib

from difflib import Differ, ndiff, SequenceMatcher, HtmlDiff
from pprint import pprint
from IPython.display import display_html, HTML, display

css_style = """
<style>
del {
    text-decoration: line-through;
    background-color: #fbb;
    color: #555;
}

ins {
    text-decoration: none;
    background-color: #d4fcbc;
}
</style>
"""

def show_diff(a, b):
  s = SequenceMatcher(None, a, b)
  unified_diff = ["<p>"]
  for tag, i1, i2, j1, j2 in s.get_opcodes():
    # print('{:7}   a[{}:{}] --> b[{}:{}] {!r:>8} --> {!r}'.format(tag, i1, i2, j1, j2, a[i1:i2], b[j1:j2]))
    if tag == "equal":
      unified_diff.append(a[i1:i2])
    else:
      unified_diff.append(f"<del>{a[i1:i2]}</del>")
      unified_diff.append(f"<ins>{b[j1:j2]}</ins>")
  unified_diff.append("</p>")
  unified_diff = "".join(unified_diff).replace("\n", "<br/>")
  return HTML(f"{css_style}\n{unified_diff}")
a, b, = 'one\ntwo\nthree\n', 'ore\ntree\nemu\n'
show_diff(a, b)

# HTML Table of Diff
d = HtmlDiff()
display(HTML(d.make_table('one\ntwo\nthree\n'.splitlines(keepends=True),
             'ore\ntree\nemu\n'.splitlines(keepends=True))))