我正在浏览一个包含卵的目录,以便将这些卵添加到sys.path。如果目录中有相同的.egg的两个版本,我只想添加最新的版本。

我有一个正则表达式r ^ (? P < eggName > \ w +) - (? P < eggVersion > (\ d \.]+)-.+\.Egg $从文件名中提取名称和版本。问题是比较版本号,它是一个像2.3.1这样的字符串。

因为我比较字符串,2排序超过10,但这是不正确的版本。

>>> "2.3.1" > "10.1.1"
True

我可以做一些拆分、解析、转换为int等,最终我将得到一个变通方法。但这是Python,不是Java。是否有一种优雅的方法来比较版本字符串?


当前回答

这是一个用于比较三个版本号的紧凑代码。注意,这里的字符串比较对所有对都失败了。

from itertools import permutations

for v1, v2 in permutations(["3.10.21", "3.10.3", "3.9.9"], 2):
    print(f"\nv1 = {v1}, v2 = {v2}")
    print(f"v1 < v2      version.parse(v1) < version.parse(v2)")
    print(f"{v1 < v2}         {version.parse(v1) < version.parse(v2)}")

这给了我们:

v1='3.10.21', v2='3.10.3'
v1 < v2      version.parse(v1) < version.parse(v2)
True         False

v1='3.10.21', v2='3.9.9'
v1 < v2      version.parse(v1) < version.parse(v2)
True         False

v1='3.10.3', v2='3.10.21'
v1 < v2      version.parse(v1) < version.parse(v2)
False         True

v1='3.10.3', v2='3.9.9'
v1 < v2      version.parse(v1) < version.parse(v2)
True         False

v1='3.9.9', v2='3.10.21'
v1 < v2      version.parse(v1) < version.parse(v2)
False         True

v1='3.9.9', v2='3.10.3'
v1 < v2      version.parse(v1) < version.parse(v2)
False         True

Permutations (iterable, 2)给出了一个可迭代对象的所有长度为2的排列。例如,

list(permutations('ABC', 2))

给了我们[(A, B), (' A ', ' C '), (A, B),(“B”、“C”)(“C”,“A”),(“C”、“B”)]。

其他回答

如果你想在一个库版本上创建一个过滤器,你可以使用__version__属性(这里是jwt库的一个例子):

from packaging import version
import jwt

if version.parse(jwt.__version__) < version.parse('2.0.0'):
    # TODO: your code

假设你的语义版本是“干净的”(例如,x.x.x),并且你有一个需要排序的版本列表,这里有一些东西可以工作。

# Here are some versions
versions = ["1.0.0", "1.10.0", "1.9.0"]

# This does not work
versions.sort() # Result: ['1.0.0', '1.10.0', '1.9.0']

# So make a list of tuple versions
tuple_versions = [tuple(map(int, (version.split(".")))) for version in versions]

# And sort the string list based on the tuple list
versions = [x for _, x in sorted(zip(tuple_versions, versions))] # Result: ['1.0.0', '1.9.0', '1.10.0']

要获得最新版本,您只需选择列表版本[-1]中的最后一个元素,或者使用sorted()的reverse属性进行反向排序,将其设置为True,并获得[0]元素。

当然,您可以将所有这些打包到一个方便的函数中以供重用。

def get_latest_version(versions):
    """
    Get the latest version from a list of versions.
    """
    try:
        tuple_versions = [tuple(map(int, (version.split(".")))) for version in versions]
        versions = [x for _, x in sorted(zip(tuple_versions, versions), reverse=True)]
        latest_version = versions[0]
    except Exception as e:
        print(e)
        latest_version = None

    return latest_version

print(get_latest_version(["1.0.0", "1.10.0", "1.9.0"]))

这是一个用于比较三个版本号的紧凑代码。注意,这里的字符串比较对所有对都失败了。

from itertools import permutations

for v1, v2 in permutations(["3.10.21", "3.10.3", "3.9.9"], 2):
    print(f"\nv1 = {v1}, v2 = {v2}")
    print(f"v1 < v2      version.parse(v1) < version.parse(v2)")
    print(f"{v1 < v2}         {version.parse(v1) < version.parse(v2)}")

这给了我们:

v1='3.10.21', v2='3.10.3'
v1 < v2      version.parse(v1) < version.parse(v2)
True         False

v1='3.10.21', v2='3.9.9'
v1 < v2      version.parse(v1) < version.parse(v2)
True         False

v1='3.10.3', v2='3.10.21'
v1 < v2      version.parse(v1) < version.parse(v2)
False         True

v1='3.10.3', v2='3.9.9'
v1 < v2      version.parse(v1) < version.parse(v2)
True         False

v1='3.9.9', v2='3.10.21'
v1 < v2      version.parse(v1) < version.parse(v2)
False         True

v1='3.9.9', v2='3.10.3'
v1 < v2      version.parse(v1) < version.parse(v2)
False         True

Permutations (iterable, 2)给出了一个可迭代对象的所有长度为2的排列。例如,

list(permutations('ABC', 2))

给了我们[(A, B), (' A ', ' C '), (A, B),(“B”、“C”)(“C”,“A”),(“C”、“B”)]。

使用python增加版本

def increment_version(version):
    version = version.split('.')
    if int(version[len(version) - 1]) >= 99:
        version[len(version) - 1] = '0'
        version[len(version) - 2] = str(int(version[len(version) - 2]) + 1)
    else:
        version[len(version) - 1] = str(int(version[len(version) - 1]) + 1)
    return '.'.join(version)

version = "1.0.0"
version_type_2 = "1.0"
print("old version",version ,"new version",increment_version(version))
print("old version",version_type_2 ,"new version",increment_version(version_type_2))

我正在寻找一个解决方案,不会增加任何新的依赖。检查以下(Python 3)解决方案:

class VersionManager:

    @staticmethod
    def compare_version_tuples(
            major_a, minor_a, bugfix_a,
            major_b, minor_b, bugfix_b,
    ):

        """
        Compare two versions a and b, each consisting of 3 integers
        (compare these as tuples)

        version_a: major_a, minor_a, bugfix_a
        version_b: major_b, minor_b, bugfix_b

        :param major_a: first part of a
        :param minor_a: second part of a
        :param bugfix_a: third part of a

        :param major_b: first part of b
        :param minor_b: second part of b
        :param bugfix_b: third part of b

        :return:    1 if a  > b
                    0 if a == b
                   -1 if a  < b
        """
        tuple_a = major_a, minor_a, bugfix_a
        tuple_b = major_b, minor_b, bugfix_b
        if tuple_a > tuple_b:
            return 1
        if tuple_b > tuple_a:
            return -1
        return 0

    @staticmethod
    def compare_version_integers(
            major_a, minor_a, bugfix_a,
            major_b, minor_b, bugfix_b,
    ):
        """
        Compare two versions a and b, each consisting of 3 integers
        (compare these as integers)

        version_a: major_a, minor_a, bugfix_a
        version_b: major_b, minor_b, bugfix_b

        :param major_a: first part of a
        :param minor_a: second part of a
        :param bugfix_a: third part of a

        :param major_b: first part of b
        :param minor_b: second part of b
        :param bugfix_b: third part of b

        :return:    1 if a  > b
                    0 if a == b
                   -1 if a  < b
        """
        # --
        if major_a > major_b:
            return 1
        if major_b > major_a:
            return -1
        # --
        if minor_a > minor_b:
            return 1
        if minor_b > minor_a:
            return -1
        # --
        if bugfix_a > bugfix_b:
            return 1
        if bugfix_b > bugfix_a:
            return -1
        # --
        return 0

    @staticmethod
    def test_compare_versions():
        functions = [
            (VersionManager.compare_version_tuples, "VersionManager.compare_version_tuples"),
            (VersionManager.compare_version_integers, "VersionManager.compare_version_integers"),
        ]
        data = [
            # expected result, version a, version b
            (1, 1, 0, 0, 0, 0, 1),
            (1, 1, 5, 5, 0, 5, 5),
            (1, 1, 0, 5, 0, 0, 5),
            (1, 0, 2, 0, 0, 1, 1),
            (1, 2, 0, 0, 1, 1, 0),
            (0, 0, 0, 0, 0, 0, 0),
            (0, -1, -1, -1, -1, -1, -1),  # works even with negative version numbers :)
            (0, 2, 2, 2, 2, 2, 2),
            (-1, 5, 5, 0, 6, 5, 0),
            (-1, 5, 5, 0, 5, 9, 0),
            (-1, 5, 5, 5, 5, 5, 6),
            (-1, 2, 5, 7, 2, 5, 8),
        ]
        count = len(data)
        index = 1
        for expected_result, major_a, minor_a, bugfix_a, major_b, minor_b, bugfix_b in data:
            for function_callback, function_name in functions:
                actual_result = function_callback(
                    major_a=major_a, minor_a=minor_a, bugfix_a=bugfix_a,
                    major_b=major_b, minor_b=minor_b, bugfix_b=bugfix_b,
                )
                outcome = expected_result == actual_result
                message = "{}/{}: {}: {}: a={}.{}.{} b={}.{}.{} expected={} actual={}".format(
                    index, count,
                    "ok" if outcome is True else "fail",
                    function_name,
                    major_a, minor_a, bugfix_a,
                    major_b, minor_b, bugfix_b,
                    expected_result, actual_result
                )
                print(message)
                assert outcome is True
                index += 1
        # test passed!


if __name__ == '__main__':
    VersionManager.test_compare_versions()

编辑:添加变量与元组比较。当然,具有元组比较的变体更好,但我正在寻找具有整数比较的变体