def test_associativity():
""" Diffs should associate, (A+B)+C=A+(B+C) """
string = "It's not much of a cheese shop, is it?"
diff_a = Diff([("not", 1, False)])
diff_b = Diff([("good", 3, True)])
diff_c = Diff([("then", 4, True)])
diff_ab = diff_a.concat(diff_b)
diff_bc = diff_b.concat(diff_c)
assert diff_c.apply(diff_ab.apply(string)) == diff_bc.apply(diff_a.apply(string))
def test_multi_add():
""" Test that diff is able to add multiple words in a single change """
string0 = "The short brown fox jumped over the lazy dog. New York Sand"
string1 = "The quick brown fox jumped over the lazy dog. " +\
"Red leather yellow leather Unique New York"
diff = Diff([
["short", 1, False],
["quick", 1, True],
["Red leather yellow leather Unique", 9, True],
["Sand", 16, False]
])
assert diff.apply(string0) == string1
def test_contatenation():
""" Check that two diffs concatenate correctly """
string = "The plumage don't enter into it. It's stone dead."
diff_a = Diff([("spam", 3, True)])
diff_b = Diff([("plumage", 1, False)])
diff_cat = diff_a.concat(diff_b)
altstring = diff_a.apply(string)
altstring = diff_b.apply(altstring)
assert diff_cat.apply(string) == altstring
def test_leading_space():
""" Test that diff is able to handle multiple spaces """
string = " Hey, everybody! Somebody 'mattress' to Mr Lambert!"
diff = Diff([("said", 4, True)])
assert diff.apply(string) == " Hey, everybody! Somebody said 'mattress' to Mr Lambert!"
def test_serialization():
""" Test that diffs serialize as expect """
string = "I want to apologize, humbly, deeply, and sincerely about the fork."
diff = Diff([("really", 1, True), ("apologize", 4, False)])
diffdct = diff.to_dict()
assert Diff.from_dict(diffdct).apply(string) == diff.apply(string)
def test_identity():
""" Concatenating a diff with its inversion should be a no-op """
string = "I'm a lumberjack, and I'm okay. I sleep all night and I work all day."
diff = Diff([("lumberjack,", 2, False), ("parrot", 6, True), ("spam", 8, True)])
no_diff = diff.concat(diff.invert())
assert no_diff.apply(string) == string
def test_invert():
""" Test that an inverted diff undoes a change """
string = "No no no, my fish's name is Eric, Eric the fish. He's an halibut."
diff = Diff([("no", 1, False), ("salt", 8, True)])
altstring = diff.apply(string)
assert diff.invert().apply(altstring) == string
def test_removal():
""" Test that a diff can remove a word as well as insert one """
string = "The deceased, Mr Apricot, jam is now 'elpless."
diff = Diff([("jam", 4, False)])
assert diff.apply(string) == "The deceased, Mr Apricot, is now 'elpless."
def test_insertion():
""" Test the basic behavior of applying a diff to a string """
string = "Hey, everybody! Somebody 'mattress' to Mr Lambert - *twice*!"
diff = Diff([("said", 3, True)])
assert diff.apply(string) == "Hey, everybody! Somebody said 'mattress' to Mr Lambert - *twice*!"