node-semver

library0.9.1pypypi✓ verified 23d ago

A Python port of the popular `node-semver` library, which provides semantic versioning utilities as used by npm. The library helps in parsing, comparing, and ranging semantic versions (MAJOR.MINOR.PATCH) according to the SemVer 2.0.0 specification. The current stable version is 0.9.0, released on February 23, 2023. This library is maintained on an as-needed basis.

serialization

pip install node-semver

github ↗package ↗

INSTALL

IMPORT

SIG · NODE-SEMVER

node-semver

serializationpythonv0.9.1

Install

1.5s avg

Import

72ms

Disk

16MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v0.9.1 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.95 runs

installs and imports cleanly · install 0.0s · import 0.074s · 17.9MB

glibc

py 3.10–3.95 runs

installs and imports cleanly · install 1.5s · import 0.070s · 18MB

16MB installed

● package 16MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

max_satisfying

✓ from nodesemver import max_satisfying

✗ from semver import max_satisfying

The module was renamed from `semver` to `nodesemver` in version 0.9.0 to avoid conflicts with `python-semver` and other libraries. Using `from semver import ...` will likely result in an `ImportError` or unexpected behavior if `python-semver` is also installed.

This quickstart demonstrates how to find the maximum version that satisfies a given semantic version range, with options for strict or loose matching and including pre-release versions.

from nodesemver import max_satisfying versions = ['1.2.3', '1.2.4', '1.2.5', '1.2.6', '2.0.1'] range_ = '~1.2.3' satisfying_version = max_satisfying(versions, range_, loose=False) print(f"Max satisfying version for range '{range_}' is: {satisfying_version}") # Expected: Max satisfying version for range '~1.2.3' is: 1.2.6 versions_with_prerelease = ['1.2.3', '1.2.4', '1.2.5', '1.2.6-pre.1', '2.0.1'] range_prerelease = '~1.2.3' satisfying_with_prerelease = max_satisfying(versions_with_prerelease, range_prerelease, loose=False, include_prerelease=True) print(f"Max satisfying (incl. prerelease) for range '{range_prerelease}' is: {satisfying_with_prerelease}") # Expected: Max satisfying (incl. prerelease) for range '~1.2.3' is: 1.2.6-pre.1

Debug

Known issues

breakingThe primary import module name changed from `semver` to `nodesemver` in version 0.9.0. Code using `from semver import ...` will fail with an `ImportError`.

fix

Update import statements to `from nodesemver import ...`.

affects: 0.9.0 and later

gotchaThis library might conflict with the `python-semver` package if both are installed and older `semver` import statements are still in use, leading to ambiguous imports.

fix

Ensure only one semantic versioning library is actively used, and update imports to `nodesemver` for this library. Consider uninstalling `python-semver` if not explicitly needed alongside `node-semver`.

affects: All versions, especially 0.9.0 onwards when migrating

gotchaWhen `loose=False`, parsing a version with a malformed pre-release (e.g., `2.0.0b1`) that doesn't strictly adhere to SemVer 2.0.0 rules can raise a `ValueError`, which may be unexpected if familiar with more permissive parsers.

fix

Catch `ValueError` when parsing potentially non-strict versions or set `loose=True` if more permissive parsing is desired.

affects: All versions

gotchaDespite a significant breaking change (module rename), the library's version number only incremented to 0.9.0, not 1.0.0, which might lead users to believe it's a minor change when it requires code modification.

fix

Always review release notes or `CHANGELOG.md` for any version update, especially when dealing with pre-1.0.0 releases where API stability guarantees are typically weaker.

affects: 0.9.0

Errors

Common errors & fixes

ModuleNotFoundError: No module named 'semver'

This error typically occurs when the `node-semver` library (prior to version 0.9.0) or another `semver` library is installed, but a conflicting `semver` package is expected, or when `node-semver` version 0.9.0 or newer is installed and the code still tries to import from `semver` instead of `nodesemver`.

fix

If you intend to use `node-semver` (version 0.9.0 or newer), update your imports from `from semver import ...` to `from nodesemver import ...`. If you intended to use the `python-semver` library (pypi.org/project/semver), ensure `node-semver` is uninstalled or upgrade `node-semver` to 0.9.0+ to prevent the module name clash. Consider using separate virtual environments if both libraries are needed in their pre-0.9.0 conflicting states.

AttributeError: module 'semver' has no attribute 'parse_version_info'

This `AttributeError` commonly happens when the `node-semver` package is installed and clobbers the `semver` namespace intended for the `python-semver` library, leading to the wrong `semver` module being loaded. The `node-semver` module (before 0.9.0) does not expose a `parse_version_info` function.

fix

Upgrade `node-semver` to version 0.9.0 or later to resolve the module name clash, and then update your imports to use `nodesemver`. Alternatively, uninstall `node-semver` if you specifically need the `python-semver` library and its `parse_version_info` function.

ValueError: Invalid Version: ~1.2.3

This error occurs when you pass a version range string (e.g., using `~` or `^`) to a `node-semver` function that expects a strict semantic version string (e.g., '1.2.3') for parsing or validation, rather than a range specification. Range operators are not considered part of a 'valid version' itself in strict SemVer.

fix

When using functions like `semver.valid()` or `semver.parse()`, provide a strict semantic version string (e.g., '1.2.3'). For evaluating against ranges, use appropriate functions like `semver.satisfies(version, range_expression)` or `semver.max_satisfying(versions, range_expression)`.

Upgrade

Version history

0.9.1latest on PyPI · released Jun 23, 2026

Audit

Dependencies

No dependency data recorded yet.

Agent activity

5 hits · last 30 days

node

Resources

githubhttps://github.com/podhmo/python-node-semver ↗

packagehttps://pypi.org/project/node-semver/ ↗