process_sem_ver

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0

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Total Lines	227
Duplicated Lines	0 %

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0

#!/usr/bin/env python

# 'Assumptions': input string follows Sem Ver 2.0
# with 2 'Limitations' on pre-release metadata and build metadata:

# 1) if user wants to include pre-release info, they must
#     - separate with dash (-) from M.m.p (ie 1.0.0-dev)
#     - only include characters from [a-z]
# 2) no build metadata are supported and string MUST end with patch or pre-release metadata

import re
import sys

if len(sys.argv) != 2:
    print("Usage: process_sem_ver.py <version>")
    print("Example: process_sem_ver.py 1.0.0-dev")
    sys.exit(1)

semver: str = sys.argv[1]


VERSION_PATTERN = r"""
    v?
    (?:
        (?:(?P<epoch>[0-9]+)!)?                           # epoch
        (?P<release>[0-9]+(?:\.[0-9]+)*)                  # release segment
        (?P<pre>                                          # pre-release
            [-_\.]?
            (?P<pre_l>(a|b|c|rc|alpha|beta|pre|preview))
            [-_\.]?
            (?P<pre_n>[0-9]+)?
        )?
        (?P<post>                                         # post release
            (?:-(?P<post_n1>[0-9]+))
            |
            (?:
                [-_\.]?
                (?P<post_l>post|rev|r)
                [-_\.]?
                (?P<post_n2>[0-9]+)?
            )
        )?
        (?P<dev>                                          # dev release
            [-_\.]?
            (?P<dev_l>dev)
            [-_\.]?
            (?P<dev_n>[0-9]+)?
        )?
    )
    (?:\+(?P<local>[a-z0-9]+(?:[-_\.][a-z0-9]+)*))?       # local version
"""

_regex = re.compile(
    r"^\s*" + VERSION_PATTERN + r"\s*$",
    re.VERBOSE | re.IGNORECASE,
)


# Verify input string meets our 'Hard Requirements', otherwise show message:
# - indicating what happened and crashed the program
# - what caused the crash
# - how the user input is part of the cause
# -  what the user should try to do, to fix the issue

# 'Hard Requirements', based on 'Assumptions' and 'Limitations' (see above):
# - string must be at least 5 characters long
# - string mush have 2 dots
# - string must end with a patch or pre-release metadata
# - string must have a dash (-) if pre-release metadata is included
# - if prerelase metadata is included, it must be only characheters from [a-z]

# Verify string is at least 5 characters long
if len(semver) < 5:
    print("[ERROR]: Sem Ver Version string must be at least 5 characters long")
    print(f"Your input: {semver}")
    print(f"Your input is only {len(semver)} characters long")
    print("Please try again with a version string that is at least 5 characters long")
    sys.exit(1)

# Verify string has 2 dots
if semver.count(".") != 2:
    print("[ERROR]: Version string must have 2 dots")
    print(f"Your input: {semver}")
    print(f"Your input has {semver.count('.')} dots")
    print("Please try again with a version string that has 2 dots")
    sys.exit(1)


# Interact with the Sem Ver 2.0 Regular Expression at https://regex101.com/r/Ly7O1x/3/
# Sem Ver 2.0 Docs related section at: https://semver.org/#is-there-a-suggested-regular-expression-regex-to-check-a-semver-string

# Note: Sem Ver 2.0 requires dash (-) to separate pre-release metadata

# Verify string ends with a patch or pre-release metadata
## Sem Ver 2.0 requires dash (-) to separate pre-release metadata

if "-" not in semver:  # if no Sem Ver 2.0 prerelease separator found in the string
    # for us now it is impossible to have pre-release metadata
    # and the string MUST be in Major.Minor.Patch format only

    if semver[-1] not in ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9"]:
        # ERROR: Should be dealing with M.m.p case, but last character is not digit
        print("[ERROR]: Version string must end with a patch or pre-release metadata")
        print(f"Your input: {semver}")
        print(f"Your input ends with {semver[-1]}")
        print(
            "Please try again with a version string that ends with a patch or pre-release metadata"
        )
        print(
            "EXPLANATION: Since we did not find a dash (-) in the input, we expect to",
            " the Input Version String to be of 'Major.Minor.Patch' format."
            " So, 'Patch' must be the last part of the string, thus the last digit must be a number."
            f"But we found {semver[-1]} instead\n."
            "If you intended to include 'pre-release' metadata,"
            " please concatenate a dash (-) to the mandatory starting 'Major.Minor.Patch' part"
            " and then add your 'pre-release' metadata, ie '1.0.0-dev'.",
        )
        sys.exit(1)

    # more reg ex checks can go here, but that not really the purpose of this script

else:  # if Sem Ver 2.0 prerelease separator found in the string
    # 1) Given the above condition
    # 2) Given scripts 'Limitations':
    #    - only characters [a-z] are allowed for prerelease metadata
    #    - we do not support 'build metadata' of Sem Ver 2.0

    # Then
    #  - expect to find exactly 1 dash (-),
    #  - the dash is right after Patch (ie Major.Minor.Patch-Prerelaese)
    #  - only [a-z] characters are found in prerelease substring
    #  - prerelease substring is not empty

    if semver.count("-") != 1:
        # ERROR: Should be dealing with M.m.p-prerelase case, but more than 1 dash found
        print("[ERROR]: Version string must have exactly 1 dash (-)")
        print(f"Your input: {semver}")
        print(f"Your input has {semver.count('-')} dashes")
        print("Please try again with a version string that has exactly 1 dash (-)")
        print(
            "EXPLANATION: Since, we found a dash (-) in the input, and given the script 'Limitation' that we do not support build-metadata, we expect",
            " the Input Version String to be of 'Major.Minor.Patch-Prerelease' format.",
        )
        sys.exit(1)

    prerelease: str = semver.split("-")[1]  # get the prerelease substring

    if prerelease == "":
        # ERROR: Should be dealing with M.m.p-prerelase case, but prerelease substring is empty
        print("[ERROR]: Version string must have a non-empty prerelease substring")
        print(f"Your input: {semver}")
        print("Your input has an empty prerelease substring")
        print(
            "Please try again with a version string that has a non-empty prerelease substring"
        )
        print(
            "EXPLANATION: Since, we found a dash (-) in the input, and given the script 'Limitation' that we do not support build-metadata, we expect",
            " the Input Version String to be of 'Major.Minor.Patch-Prerelease' format.",
        )
        sys.exit(1)

    # english alphabet has 26 characters
    # lowercase_chars = set(chr(ord("a") + i) for i in range(26))
    # if lowercase_chars.issuperset(prerelease) is False:
    #     # ERROR: Should be dealing with M.m.p-prerelase case, but found non [a-z] characters in prerelease substring
    #     print("[ERROR]: Version string's prerelease must have only [a-z] characters")
    #     print(f"Your input: {semver}")
    #     print(f"Your input has {prerelease}")
    #     print(
    #         "Please try again with a version string that has only [a-z] characters in prerelease substring"
    #     )
    #     print(
    #         "EXPLANATION: Since we found a dash (-) in the input, we expect to",
    #         " the Input Version String to be of 'Major.Minor.Patch-Prerelease' format.",
    #     )
    #     sys.exit(1)

    # more reg ex checks can go here, but that not really the purpose of this script


# If we got here, then the input string is a valid Sem Ver 2.0 string
# And valid as input to the rest of the script


# CRITICAL to be in par with Pip sdist /wheel and python -m build operations
# https://peps.python.org/pep-0440/#compatibility-with-other-version-schemes


parsed_versions_string = _regex.match(semver)

prerelease = parsed_versions_string.group("pre") or parsed_versions_string.group("dev") or ''

sep = ''

to_add = ''
if prerelease:
    prerelease = prerelease.replace('.', '').replace('-', '').replace('_', '')

    if prerelease.startswith('rc'):
        sep = ''
    elif prerelease.startswith('dev'):
        sep = '.'
    else:
        # don't have code hre to handle yet
        print('ERROR: Our current limitation is that prerelease must start with rc or dev')
        print(f'Your input: {semver}')
        print(f'Your input has {prerelease}')
        sys.exit(1)

    string = prerelease.replace('rc', '').replace('dev', '')

    try:
        int(string)
        # last part is a number already, so we keep that as it is
        to_add = ''
    except ValueError:
        to_add = '0'


print(
    f'{parsed_versions_string.group("epoch") or ""}'
    f'{parsed_versions_string.group("release")}'
    f'{sep}{prerelease}{to_add}'
)

assert sys.argv[1] == semver