enhance singular_noun

[BBC-Esq]

This fixes the issue with #222 and is an improvement. However, it is not a perfect solution for all other possible phrases.

Summary of Changes:

1. Added Handling for Irregular Plurals:

   • Introduced a new helper function, handle_irregular_plural(), which checks if a word is an irregular plural and replaces it with its singular form when necessary.
   • Uses pl_sb_irregular.values() to determine if the word is irregular and maps it back to its singular form.

2. Improved Inflection Handling:

   • The inflection process now includes logic to avoid unnecessary pluralization when count != 1 but the word already ends in 's'.
   • Ensures irregular plural forms are properly converted using handle_irregular_plural().

3. Refactored Inflection Logic:

   • The original inflection(cand, count) call is now stored in a for loop to ensure that it is only computed once and can be used in multiple checks.
   • Used a conditional expression to determine whether the candidate word (cand) should be replaced with the inflected version or left unchanged.

4. Removed Docstring Examples:

   • The revised version omits the docstring examples (doctests), which were present in the original method.

Possible Future Improvements

Here is a script that illustrates other scenarios that are related conceptually but that this PR decided to not address at this time, for your future improvements:

TEST SCRIPT

import inflect
from typing import Union, Dict, Tuple

GREEN = "\033[92m"
RED = "\033[91m"
RESET = "\033[0m"

p = inflect.engine()

expected_results = {
    # Your existing test cases
    "pair of scissors": ("pair of scissors", "pairs of scissors"),
    "pairs of scissors": ("pair of scissors", "pairs of scissors"),
    "mother in law": ("mother in law", "mothers in law"),
    "mothers in law": ("mother in law", "mothers in law"),
    "student of physics": ("student of physics", "students of physics"),
    "students of physics": ("student of physics", "students of physics"),
    "piece of cake": ("piece of cake", "pieces of cake"),
    "pieces of cake": ("piece of cake", "pieces of cake"),
    "man at arms": ("man at arms", "men at arms"),
    "men at arms": ("man at arms", "men at arms"),
    "right of way": ("right of way", "rights of way"),
    "rights of way": ("right of way", "rights of way"),
    "editor in chief": ("editor in chief", "editors in chief"),
    "editors in chief": ("editor in chief", "editors in chief"),
    "secretary of state": ("secretary of state", "secretaries of state"),
    "secretaries of state": ("secretary of state", "secretaries of state"),
    "court of law": ("court of law", "courts of law"),
    "courts of law": ("court of law", "courts of law"),
    "brother in arms": ("brother in arms", "brothers in arms"),
    "brothers in arms": ("brother in arms", "brothers in arms"),
    "head of household": ("head of household", "heads of household"),
    "heads of household": ("head of household", "heads of household"),
    
    # 1. Compound words with different plural forms
    "attorney general": ("attorney general", "attorneys general"),
    "attorney at law": ("attorney at law", "attorneys at law"),
    "commander in chief": ("commander in chief", "commanders in chief"),
    "passer by": ("passer by", "passers by"),
    "runner up": ("runner up", "runners up"),
    
    # 2. Words with irregular plurals
    "criterion": ("criterion", "criteria"),
    "phenomenon": ("phenomenon", "phenomena"),
    "thesis": ("thesis", "theses"),
    "analysis": ("analysis", "analyses"),
    "datum": ("datum", "data"),
    
    # 3. Compound phrases with possessives
    "child's play": ("child's play", "children's play"),
    "wolf's bane": ("wolf's bane", "wolves' bane"),
    
    # 4. Hyphenated compounds
    "father-in-law": ("father-in-law", "fathers-in-law"),
    "merry-go-round": ("merry-go-round", "merry-go-rounds"),
    
    # 5. Words that maintain the same form
    "species": ("species", "species"),
    "series": ("series", "series"),
    "means": ("means", "means"),
    
    # 6. Words with multiple accepted plurals
    "octopus": ("octopus", "octopi"),
    "formula": ("formula", "formulae"),
    "cactus": ("cactus", "cacti")
}

error_expected_results = {
    "": ("", ""),
    "of": (False, "ofs"),
    "pair scissors of": (False, "pair scissors ofs"),
    "student physics of": (False, "student physics ofs"),
    "pair_of_scissors": (False, "pair_of_scissorses"),
    "of of of": (False, "of of ofs"),
    "pair-of-scissors": ("pair-of-scissors", "pairs-of-scissors"),
    "   pair of scissors   ": ("   pair of scissors   ", "   pairs of scissors   "),
    "PaIr Of ScIsSoRs": ("PaIr Of ScIsSoRs", "PaIrS Of ScIsSoRs")
}

def check_result(actual: Union[str, bool], expected: Union[str, bool]) -> bool:
    if expected is False:
        return actual is False
    return actual == expected

def print_result(passed: bool, message: str = ""):
    if passed:
        print(f"{GREEN}✓ Correct{RESET} {message}")
    else:
        print(f"{RED}✗ Failed{RESET} {message}")

print("Testing Regular Cases")
print("-" * 75)

for phrase in expected_results:
    print(f"\nTesting: '{phrase}'")
    expected_sing, expected_plur = expected_results[phrase]
    
    singular_result = p.singular_noun(phrase)
    singular_display = singular_result if singular_result is not False else "[already singular]"
    print(f"Singular:  {singular_display}")
    print_result(check_result(singular_result, expected_sing), 
                f"(Expected: {expected_sing})")
    
    plural_result = p.plural_noun(phrase)
    print(f"Plural:    {plural_result}")
    print_result(plural_result == expected_plur, 
                f"(Expected: {expected_plur})")
    
    final_singular = p.singular_noun(plural_result)
    final_display = final_singular if final_singular is not False else "[already singular]"
    print(f"Back to singular: {final_display}")
    print_result(check_result(final_singular, expected_sing), 
                f"(Expected: {expected_sing})")

print("\nTesting Error Cases")
print("-" * 75)

for phrase in error_expected_results:
    print(f"\nTesting: '{phrase}'")
    expected_sing, expected_plur = error_expected_results[phrase]
    
    try:
        singular = p.singular_noun(phrase)
        print(f"Singular attempt: {singular}")
        print_result(check_result(singular, expected_sing), 
                    f"(Expected: {expected_sing})")
    except Exception as e:
        if isinstance(expected_sing, type) and isinstance(e, expected_sing):
            print_result(True, f"Got expected exception: {type(e).__name__}")
        else:
            print_result(False, f"Got unexpected exception: {type(e).__name__}")
    
    try:
        plural = p.plural_noun(phrase)
        print(f"Plural attempt: {plural}")
        print_result(plural == expected_plur, 
                    f"(Expected: {expected_plur})")
    except Exception as e:
        if isinstance(expected_plur, type) and isinstance(e, expected_plur):
            print_result(True, f"Got expected exception: {type(e).__name__}")
        else:
            print_result(False, f"Got unexpected exception: {type(e).__name__}")