Code Review

Great effort on this PR!

The code tackles the deduplication task with a good regex-based approach and a class to manage name components. However, there are several areas to improve for requirements-compliance, robustness, readibility, maintainability. Sharing some feedback below:

Separation of concerns:

The code mixes name patterns, parsing logic, and I/O in one file.

• Suggestion: Split into modules
  • name_parser.py: Define regexes and handles name parsing
  • models.py: Define Name class
  • main.py: Handle input/output

This would allow for a better code-flow improving readibility and extensibility. Testing these components individually should become simpler too.

Regex implementation

• Using initial_regex % "first is clever but a bit obscure.
• For derived patetrns, using .join and simple concatenation is inconcistent.
• Bug: name_regex_five lacks a $ at the end
• Emails should also be validated with a regex. Use an off-the-shelf regex for the same. Good reference from regexlib: https://regexlib.com/search.aspx?k=email
• Case Sensitivity: Add re.IGNORECASE
• Something to check with product:
  • Can names have special characters, eg. O'Brian. Adjust regexes accordingly.

Could do something like this perhaps?

# Base components with clear naming
NAME_COMPONENT = r"[a-zA-Z\-']+"
INITIAL_COMPONENT = r"[a-zA-Z]\."

# Pattern definitions
FIRST_NAME_PATTERN = f"(?P<first_name>{NAME_COMPONENT})"
LAST_NAME_PATTERN = f"(?P<last_name>{NAME_COMPONENT})"
MIDDLE_NAME_PATTERN = f"(?P<middle_name>{NAME_COMPONENT})"
FIRST_INITIAL_PATTERN = f"(?P<first_initial>{INITIAL_COMPONENT})"
MIDDLE_INITIAL_PATTERN = f"(?P<middle_initial>{INITIAL_COMPONENT})"

NAME_PATTERNS = [
    # Pattern 1: First name only or First + Last name
    re.compile(f"^{FIRST_NAME_PATTERN}(?: {LAST_NAME_PATTERN})?$", re.IGNORECASE),
]

Logic and Error handling

• Name Updating Issue: The update method doesn’t replace initials with full names (e.g., "J." should become "John" if "John" is provided later). Something on these lines:

if k == "first_name" and hasattr(self, "first_initial"):
    delattr(self, "first_initial")  # Replace initial with full name
    elif k == "middle_name" and hasattr(self, "middle_initial"):
        delattr(self, "middle_initial")
    setattr(self, k, v)

Separately, a different way to tackle this is to define the attributes explicitly in the name class and set them during updates. Then, you only need to form the canonical output names based on what's avialable for a particular name. This is a bigger change from your code, so prefer only if time permits.

• Name Parsing: get_email_and_name assumes a regex will match.
  • Add error handling using try..except when line format or regex don't match
  • Add appropriate logging and continue
• Final Output
  • Bug: Current Output is name: email which doesn;t match the requirements.
  • Final output needs to be changed from colon-delimited string currently to json
  • Add error handling for File i/o
    • Throw "File Not found exception"
    • Handling empty lines, currently it breaks if any empty line found

Testing and other improvements if time

• Unit Tests: Add tests to verify behavior

def test_name_parsing():
    assert get_email_and_name("John:[email protected]")[0] == {"first_name": "John"}
    assert get_email_and_name("J. F. Kennedy:[email protected]")[0] == {
        "first_initial": "J.", "middle_initial": "F.", "last_name": "Kennedy"
    }

• Documentation Add Docstrings to improve readability

Final Thoughts

This is a promising first attempt! After addressing the bugs, enhancing the update logic, adding error handling, and fixing the output format, this will meet the requirements. Please update the PR with these changes and add some tests. Let me know if you need help implementing any of these suggestions!