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semver(1) -- The semantic versioner for npm =========================================== ## Install ```bash npm install --save semver ```` ## Usage As a node module: ```js const semver = require('semver') semver.valid('1.2.3') // '1.2.3' semver.valid('a.b.c') // null semver.clean(' =v1.2.3 ') // '1.2.3' semver.satisfies('1.2.3', '1.x || >=2.5.0 || 5.0.0 - 7.2.3') // true semver.gt('1.2.3', '9.8.7') // false semver.lt('1.2.3', '9.8.7') // true semver.minVersion('>=1.0.0') // '1.0.0' semver.valid(semver.coerce('v2')) // '2.0.0' semver.valid(semver.coerce('42.6.7.9.3-alpha')) // '42.6.7' ``` As a command-line utility: ``` $ semver -h A JavaScript implementation of the https://semver.org/ specification Copyright Isaac Z. Schlueter Usage: semver [options] <version> [<version> [...]] Prints valid versions sorted by SemVer precedence Options: -r --range <range> Print versions that match the specified range. -i --increment [<level>] Increment a version by the specified level. Level can be one of: major, minor, patch, premajor, preminor, prepatch, or prerelease. Default level is 'patch'. Only one version may be specified. --preid <identifier> Identifier to be used to prefix premajor, preminor, prepatch or prerelease version increments. -l --loose Interpret versions and ranges loosely -p --include-prerelease Always include prerelease versions in range matching -c --coerce Coerce a string into SemVer if possible (does not imply --loose) Program exits successfully if any valid version satisfies all supplied ranges, and prints all satisfying versions. If no satisfying versions are found, then exits failure. Versions are printed in ascending order, so supplying multiple versions to the utility will just sort them. ``` ## Versions A "version" is described by the `v2.0.0` specification found at <https://semver.org/>. A leading `"="` or `"v"` character is stripped off and ignored. ## Ranges A `version range` is a set of `comparators` which specify versions that satisfy the range. A `comparator` is composed of an `operator` and a `version`. The set of primitive `operators` is: * `<` Less than * `<=` Less than or equal to * `>` Greater than * `>=` Greater than or equal to * `=` Equal. If no operator is specified, then equality is assumed, so this operator is optional, but MAY be included. For example, the comparator `>=1.2.7` would match the versions `1.2.7`, `1.2.8`, `2.5.3`, and `1.3.9`, but not the versions `1.2.6` or `1.1.0`. Comparators can be joined by whitespace to form a `comparator set`, which is satisfied by the **intersection** of all of the comparators it includes. A range is composed of one or more comparator sets, joined by `||`. A version matches a range if and only if every comparator in at least one of the `||`-separated comparator sets is satisfied by the version. For example, the range `>=1.2.7 <1.3.0` would match the versions `1.2.7`, `1.2.8`, and `1.2.99`, but not the versions `1.2.6`, `1.3.0`, or `1.1.0`. The range `1.2.7 || >=1.2.9 <2.0.0` would match the versions `1.2.7`, `1.2.9`, and `1.4.6`, but not the versions `1.2.8` or `2.0.0`. ### Prerelease Tags If a version has a prerelease tag (for example, `1.2.3-alpha.3`) then it will only be allowed to satisfy comparator sets if at least one comparator with the same `[major, minor, patch]` tuple also has a prerelease tag. For example, the range `>1.2.3-alpha.3` would be allowed to match the version `1.2.3-alpha.7`, but it would *not* be satisfied by `3.4.5-alpha.9`, even though `3.4.5-alpha.9` is technically "greater than" `1.2.3-alpha.3` according to the SemVer sort rules. The version range only accepts prerelease tags on the `1.2.3` version. The version `3.4.5` *would* satisfy the range, because it does not have a prerelease flag, and `3.4.5` is greater than `1.2.3-alpha.7`. The purpose for this behavior is twofold. First, prerelease versions frequently are updated very quickly, and contain many breaking changes that are (by the author's design) not yet fit for public consumption. Therefore, by default, they are excluded from range matching semantics. Second, a user who has opted into using a prerelease version has clearly indicated the intent to use *that specific* set of alpha/beta/rc versions. By including a prerelease tag in the range, the user is indicating that they are aware of the risk. However, it is still not appropriate to assume that they have opted into taking a similar risk on the *next* set of prerelease versions. Note that this behavior can be suppressed (treating all prerelease versions as if they were normal versions, for the purpose of range matching) by setting the `includePrerelease` flag on the options object to any [functions](https://github.com/npm/node-semver#functions) that do range matching. #### Prerelease Identifiers The method `.inc` takes an additional `identifier` string argument that will append the value of the string as a prerelease identifier: ```javascript semver.inc('1.2.3', 'prerelease', 'beta') // '1.2.4-beta.0' ``` command-line example: ```bash $ semver 1.2.3 -i prerelease --preid beta 1.2.4-beta.0 ``` Which then can be used to increment further: ```bash $ semver 1.2.4-beta.0 -i prerelease 1.2.4-beta.1 ``` ### Advanced Range Syntax Advanced range syntax desugars to primitive comparators in deterministic ways. Advanced ranges may be combined in the same way as primitive comparators using white space or `||`. #### Hyphen Ranges `X.Y.Z - A.B.C` Specifies an inclusive set. * `1.2.3 - 2.3.4` := `>=1.2.3 <=2.3.4` If a partial version is provided as the first version in the inclusive range, then the missing pieces are replaced with zeroes. * `1.2 - 2.3.4` := `>=1.2.0 <=2.3.4` If a partial version is provided as the second version in the inclusive range, then all versions that start with the supplied parts of the tuple are accepted, but nothing that would be greater than the provided tuple parts. * `1.2.3 - 2.3` := `>=1.2.3 <2.4.0` * `1.2.3 - 2` := `>=1.2.3 <3.0.0` #### X-Ranges `1.2.x` `1.X` `1.2.*` `*` Any of `X`, `x`, or `*` may be used to "stand in" for one of the numeric values in the `[major, minor, patch]` tuple. * `*` := `>=0.0.0` (Any version satisfies) * `1.x` := `>=1.0.0 <2.0.0` (Matching major version) * `1.2.x` := `>=1.2.0 <1.3.0` (Matching major and minor versions) A partial version range is treated as an X-Range, so the special character is in fact optional. * `""` (empty string) := `*` := `>=0.0.0` * `1` := `1.x.x` := `>=1.0.0 <2.0.0` * `1.2` := `1.2.x` := `>=1.2.0 <1.3.0` #### Tilde Ranges `~1.2.3` `~1.2` `~1` Allows patch-level changes if a minor version is specified on the comparator. Allows minor-level changes if not. * `~1.2.3` := `>=1.2.3 <1.(2+1).0` := `>=1.2.3 <1.3.0` * `~1.2` := `>=1.2.0 <1.(2+1).0` := `>=1.2.0 <1.3.0` (Same as `1.2.x`) * `~1` := `>=1.0.0 <(1+1).0.0` := `>=1.0.0 <2.0.0` (Same as `1.x`) * `~0.2.3` := `>=0.2.3 <0.(2+1).0` := `>=0.2.3 <0.3.0` * `~0.2` := `>=0.2.0 <0.(2+1).0` := `>=0.2.0 <0.3.0` (Same as `0.2.x`) * `~0` := `>=0.0.0 <(0+1).0.0` := `>=0.0.0 <1.0.0` (Same as `0.x`) * `~1.2.3-beta.2` := `>=1.2.3-beta.2 <1.3.0` Note that prereleases in the `1.2.3` version will be allowed, if they are greater than or equal to `beta.2`. So, `1.2.3-beta.4` would be allowed, but `1.2.4-beta.2` would not, because it is a prerelease of a different `[major, minor, patch]` tuple. #### Caret Ranges `^1.2.3` `^0.2.5` `^0.0.4` Allows changes that do not modify the left-most non-zero digit in the `[major, minor, patch]` tuple. In other words, this allows patch and minor updates for versions `1.0.0` and above, patch updates for versions `0.X >=0.1.0`, and *no* updates for versions `0.0.X`. Many authors treat a `0.x` version as if the `x` were the major "breaking-change" indicator. Caret ranges are ideal when an author may make breaking changes between `0.2.4` and `0.3.