Table of contents
semver
Select CLI Version:
Table of contents
Install
npm install --save semver
Usage
As a node module:
const semver = require("semver");semver.valid("1.2.3"); // '1.2.3'semver.valid("a.b.c"); // nullsemver.clean(" =v1.2.3 "); // '1.2.3'semver.satisfies("1.2.3", "1.x || >=2.5.0 || 5.0.0 - 7.2.3"); // truesemver.gt("1.2.3", "9.8.7"); // falsesemver.lt("1.2.3", "9.8.7"); // truesemver.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 -hA JavaScript implementation of the https://semver.org/ specificationCopyright Isaac Z. SchlueterUsage: semver [options] <version> [<version> [...]]Prints valid versions sorted by SemVer precedenceOptions:-r --range <range>Print versions that match the specified range.-i --increment [<level>]Increment a version by the specified level. Level canbe 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 --looseInterpret versions and ranges loosely-p --include-prereleaseAlways include prerelease versions in range matching-c --coerceCoerce a string into SemVer if possible(does not imply --loose)Program exits successfully if any valid version satisfiesall supplied ranges, and prints all satisfying versions.If no satisfying versions are found, then exits failure.Versions are printed in ascending order, so supplyingmultiple 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 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:
semver.inc("1.2.3", "prerelease", "beta");// '1.2.4-beta.0'
command-line example:
$ semver 1.2.3 -i prerelease --preid beta1.2.4-beta.0
Which then can be used to increment further:
$ semver 1.2.4-beta.0 -i prerelease1.2.4-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 as1.2.x
)~1
:=>=1.0.0 <(1+1).0.0
:=>=1.0.0 <2.0.0
(Same as1.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 as0.2.x
)~0
:=>=0.0.0 <(0+1).0.0
:=>=0.0.0 <1.0.0
(Same as0.x
)~1.2.3-beta.2
:=>=1.2.3-beta.2 <1.3.0
Note that prereleases in the1.2.3
version will be allowed, if they are greater than or equal tobeta.2
. So,1.2.3-beta.4
would be allowed, but1.2.4-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 0.3.0
releases, which is a common practice. However, it presumes that there will not be breaking changes between 0.2.4
and 0.2.5
. It allows for changes that are presumed to be additive (but non-breaking), according to commonly observed practices.
^1.2.3
:=>=1.2.3 <2.0.0
^0.2.3
:=>=0.2.3 <0.3.0
^0.0.3
:=>=0.0.3 <0.0.4
^1.2.3-beta.2
:=>=1.2.3-beta.2 <2.0.0
Note that prereleases in the1.2.3
version will be allowed, if they are greater than or equal tobeta.2
. So,1.2.3-beta.4
would be allowed, but1.2.4-beta.2
would not, because it is a prerelease of a different[major, minor, patch]
tuple.^0.0.3-beta
:=>=0.0.3-beta <0.0.4
Note that prereleases in the0.0.3
version only will be allowed, if they are greater than or equal tobeta
. So,0.0.3-pr.2
would be allowed.
When parsing caret ranges, a missing patch
value desugars to the number 0
, but will allow flexibility within that value, even if the major and minor versions are both 0
.
^1.2.x
:=>=1.2.0 <2.0.0
^0.0.x
:=>=0.0.0 <0.1.0
^0.0
:=>=0.0.0 <0.1.0
A missing minor
and patch
values will desugar to zero, but also allow flexibility within those values, even if the major version is zero.
^1.x
:=>=1.0.0 <2.0.0
^0.x
:=>=0.0.0 <1.0.0
Range Grammar
Putting all this together, here is a Backus-Naur grammar for ranges, for the benefit of parser authors:
range-set ::= range ( logical-or range ) *logical-or ::= ( ' ' ) * '||' ( ' ' ) *range ::= hyphen | simple ( ' ' simple ) * | ''hyphen ::= partial ' - ' partialsimple ::= primitive | partial | tilde | caretprimitive ::= ( '<' | '>' | '>=' | '<=' | '=' ) partialpartial ::= xr ( '.' xr ( '.' xr qualifier ? )? )?xr ::= 'x' | 'X' | '*' | nrnr ::= '0' | ['1'-'9'] ( ['0'-'9'] ) *tilde ::= '~' partialcaret ::= '^' partialqualifier ::= ( '-' pre )? ( '+' build )?pre ::= partsbuild ::= partsparts ::= part ( '.' part ) *part ::= nr | [-0-9A-Za-z]+
Functions
All methods and classes take a final options
object argument. All options in this object are false
by default. The options supported are:
loose
Be more forgiving about not-quite-valid semver strings. (Any resulting output will always be 100% strict compliant, of course.) For backwards compatibility reasons, if theoptions
argument is a boolean value instead of an object, it is interpreted to be theloose
param.includePrerelease
Set to suppress the default behavior of excluding prerelease tagged versions from ranges unless they are explicitly opted into.
Strict-mode Comparators and Ranges will be strict about the SemVer strings that they parse.
valid(v)
: Return the parsed version, or null if it's not valid.inc(v, release)
: Return the version incremented by the release type (major
,premajor
,minor
,preminor
,patch
,prepatch
, orprerelease
), or null if it's not validpremajor
in one call will bump the version up to the next major version and down to a prerelease of that major version.preminor
, andprepatch
work the same way.- If called from a non-prerelease version, the
prerelease
will work the same asprepatch
. It increments the patch version, then makes a prerelease. If the input version is already a prerelease it simply increments it.
prerelease(v)
: Returns an array of prerelease components, or null if none exist. Example:prerelease('1.2.3-alpha.1') -> ['alpha', 1]
major(v)
: Return the major version number.minor(v)
: Return the minor version number.patch(v)
: Return the patch version number.intersects(r1, r2, loose)
: Return true if the two supplied ranges or comparators intersect.parse(v)
: Attempt to parse a string as a semantic version, returning either aSemVer
object ornull
.
Comparison
gt(v1, v2)
:v1 > v2
gte(v1, v2)
:v1 >= v2
lt(v1, v2)
:v1 < v2
lte(v1, v2)
:v1 <= v2
eq(v1, v2)
:v1 == v2
This is true if they're logically equivalent, even if they're not the exact same string. You already know how to compare strings.neq(v1, v2)
:v1 != v2
The opposite ofeq
.cmp(v1, comparator, v2)
: Pass in a comparison string, and it'll call the corresponding function above."==="
and"!=="
do simple string comparison, but are included for completeness. Throws if an invalid comparison string is provided.compare(v1, v2)
: Return0
ifv1 == v2
, or1
ifv1
is greater, or-1
ifv2
is greater. Sorts in ascending order if passed toArray.sort()
.rcompare(v1, v2)
: The reverse of compare. Sorts an array of versions in descending order when passed toArray.sort()
.diff(v1, v2)
: Returns difference between two versions by the release type (major
,premajor
,minor
,preminor
,patch
,prepatch
, orprerelease
), or null if the versions are the same.
Comparators
intersects(comparator)
: Return true if the comparators intersect
Ranges
validRange(range)
: Return the valid range or null if it's not validsatisfies(version, range)
: Return true if the version satisfies the range.maxSatisfying(versions, range)
: Return the highest version in the list that satisfies the range, ornull
if none of them do.minSatisfying(versions, range)
: Return the lowest version in the list that satisfies the range, ornull
if none of them do.minVersion(range)
: Return the lowest version that can possibly match the given range.gtr(version, range)
: Returntrue
if version is greater than all the versions possible in the range.ltr(version, range)
: Returntrue
if version is less than all the versions possible in the range.outside(version, range, hilo)
: Return true if the version is outside the bounds of the range in either the high or low direction. Thehilo
argument must be either the string'>'
or'<'
. (This is the function called bygtr
andltr
.)intersects(range)
: Return true if any of the ranges comparators intersect
Note that, since ranges may be non-contiguous, a version might not be greater than a range, less than a range, or satisfy a range! For example, the range 1.2 <1.2.9 || >2.0.0
would have a hole from 1.2.9
until 2.0.0
, so the version 1.2.10
would not be greater than the range (because 2.0.1
satisfies, which is higher), nor less than the range (since 1.2.8
satisfies, which is lower), and it also does not satisfy the range.
If you want to know if a version satisfies or does not satisfy a range, use the satisfies(version, range)
function.
Coercion
coerce(version)
: Coerces a string to semver if possible
This aims to provide a very forgiving translation of a non-semver string to semver. It looks for the first digit in a string, and consumes all remaining characters which satisfy at least a partial semver (e.g., 1
, 1.2
, 1.2.3
) up to the max permitted length (256 characters). Longer versions are simply truncated (4.6.3.9.2-alpha2
becomes 4.6.3
). All surrounding text is simply ignored (v3.4 replaces v3.3.1
becomes 3.4.0
). Only text which lacks digits will fail coercion (version one
is not valid). The maximum length for any semver component considered for coercion is 16 characters; longer components will be ignored (10000000000000000.4.7.4
becomes 4.7.4
). The maximum value for any semver component is Number.MAX_SAFE_INTEGER || (2**53 - 1)
; higher value components are invalid (9999999999999999.4.7.4
is likely invalid).