Python: String to CamelCase

Question

This is a question from Codewars: Complete the method/function so that it converts dash/underscore delimited words into camel casing. The first word within the output should be capitalized only if the original word was capitalized (known as Upper Camel Case, also often referred to as Pascal case).

The input test cases are as follows:

test.describe("Testing function to_camel_case")
test.it("Basic tests")
test.assert_equals(to_camel_case(''), '', "An empty string was provided but not returned")
test.assert_equals(to_camel_case("the_stealth_warrior"), "theStealthWarrior", "to_camel_case('the_stealth_warrior') did not return correct value")
test.assert_equals(to_camel_case("The-Stealth-Warrior"), "TheStealthWarrior", "to_camel_case('The-Stealth-Warrior') did not return correct value")
test.assert_equals(to_camel_case("A-B-C"), "ABC", "to_camel_case('A-B-C') did not return correct value")

This is what I've tried so far:

def to_camel_case(text):
    str=text
    str=str.replace(' ','')
    for i in str:
        if ( str[i] == '-'):
            str[i]=str.replace('-','')
            str[i+1].toUpperCase()
        elif ( str[i] == '_'):
            str[i]=str.replace('-','')
            str[i+1].toUpperCase()
    return str

It passes the first two tests but not the main ones :

 test.assert_equals(to_camel_case("the_stealth_warrior"), "theStealthWarrior", "to_camel_case('the_stealth_warrior') did not return correct value")
    test.assert_equals(to_camel_case("The-Stealth-Warrior"), "TheStealthWarrior", "to_camel_case('The-Stealth-Warrior') did not return correct value")
    test.assert_equals(to_camel_case("A-B-C"), "ABC", "to_camel_case('A-B-C') did not return correct value")

What am I doing wrong?

Answer 1

You may have a working implementation with slight errors as mentioned in your comments, but I propose that you:

• split by the delimiters

• apply a capitalization for all but the first of the tokens

• rejoin the tokens

My implementation is:

def to_camel_case(text):
    s = text.replace("-", " ").replace("_", " ")
    s = s.split()
    if len(text) == 0:
        return text
    return s[0] + ''.join(i.capitalize() for i in s[1:])

IMO it makes a bit more sense. The output from running tests is:

>>> to_camel_case("the_stealth_warrior")
'theStealthWarrior'
>>> to_camel_case("The-Stealth-Warrior")
'TheStealthWarrior'
>>> to_camel_case("A-B-C")
'ABC'

Answer 2

from re import sub

def to_camelcase(s):
  s = sub(r"(_|-)+", " ", s).title().replace(" ", "").replace("*","")
  return ''.join([s[0].lower(), s[1:]])

print(to_camelcase('some_string_with_underscore'))
print(to_camelcase('Some string with Spaces'))
print(to_camelcase('some-string-with-dashes'))
print(to_camelcase('some string-with dashes_underscores and spaces'))
print(to_camelcase('some*string*with*asterisks'))