1SEMVER(7) SEMVER(7)
2
6 semver - The semantic versioner for npm
7
9 npm install --save semver
10
12 As a node module:
13 const semver = require('semver')
15 semver.valid('1.2.3') // '1.2.3'
17 semver.valid('a.b.c') // null
18 semver.clean(' =v1.2.3 ') // '1.2.3'
19 semver.satisfies('1.2.3', '1.x || >=2.5.0 || 5.0.0 - 7.2.3') // true
20 semver.gt('1.2.3', '9.8.7') // false
21 semver.lt('1.2.3', '9.8.7') // true
22 semver.minVersion('>=1.0.0') // '1.0.0'
23 semver.valid(semver.coerce('v2')) // '2.0.0'
24 semver.valid(semver.coerce('42.6.7.9.3-alpha')) // '42.6.7'
25 As a command-line utility:
27 $ semver -h
29 A JavaScript implementation of the https://semver.org/ specification
31 Copyright Isaac Z. Schlueter
32 Usage: semver [options] <version> [<version> [...]]
34 Prints valid versions sorted by SemVer precedence
35 Options:
37 -r --range <range>
38 Print versions that match the specified range.
39 -i --increment [<level>]
41 Increment a version by the specified level. Level can
42 be one of: major, minor, patch, premajor, preminor,
43 prepatch, or prerelease. Default level is 'patch'.
44 Only one version may be specified.
45 --preid <identifier>
47 Identifier to be used to prefix premajor, preminor,
48 prepatch or prerelease version increments.
49 -l --loose
51 Interpret versions and ranges loosely
52 -p --include-prerelease
54 Always include prerelease versions in range matching
55 -c --coerce
57 Coerce a string into SemVer if possible
58 (does not imply --loose)
59 Program exits successfully if any valid version satisfies
61 all supplied ranges, and prints all satisfying versions.
62 If no satisfying versions are found, then exits failure.
64 Versions are printed in ascending order, so supplying
66 multiple versions to the utility will just sort them.
67
69 A "version" is described by the v2.0.0 specification found at
70 https://semver.org/.
71 A leading "=" or "v" character is stripped off and ignored.
73
75 A version range is a set of comparators which specify versions that
76 satisfy the range.
77 A comparator is composed of an operator and a version. The set of
79 primitive operators is:
80 • < Less than
82 • <= Less than or equal to
84 • > Greater than
86 • >= Greater than or equal to
88 • = Equal. If no operator is specified, then equality is assumed, so
90 this operator is optional, but MAY be included.
91 For example, the comparator >=1.2.7 would match the versions 1.2.7,
94 1.2.8, 2.5.3, and 1.3.9, but not the versions 1.2.6 or 1.1.0.
95 Comparators can be joined by whitespace to form a comparator set, which
97 is satisfied by the intersection of all of the comparators it includes.
98 A range is composed of one or more comparator sets, joined by ||. A
100 version matches a range if and only if every comparator in at least one
101 of the ||-separated comparator sets is satisfied by the version.
102 For example, the range >=1.2.7 <1.3.0 would match the versions 1.2.7,
104 1.2.8, and 1.2.99, but not the versions 1.2.6, 1.3.0, or 1.1.0.
105 The range 1.2.7 || >=1.2.9 <2.0.0 would match the versions 1.2.7,
107 1.2.9, and 1.4.6, but not the versions 1.2.8 or 2.0.0.
108 Prerelease Tags
110 If a version has a prerelease tag (for example, 1.2.3-alpha.3) then it
111 will only be allowed to satisfy comparator sets if at least one com‐
112 parator with the same [major, minor, patch] tuple also has a prerelease
113 tag.
114 For example, the range >1.2.3-alpha.3 would be allowed to match the
116 version 1.2.3-alpha.7, but it would not be satisfied by 3.4.5-alpha.9,
117 even though 3.4.5-alpha.9 is technically "greater than" 1.2.3-alpha.3
118 according to the SemVer sort rules. The version range only accepts
119 prerelease tags on the 1.2.3 version. The version 3.4.5 would satisfy
120 the range, because it does not have a prerelease flag, and 3.4.5 is
121 greater than 1.2.3-alpha.7.
122 The purpose for this behavior is twofold. First, prerelease versions
124 frequently are updated very quickly, and contain many breaking changes
125 that are (by the author's design) not yet fit for public consumption.
126 Therefore, by default, they are excluded from range matching semantics.
127 Second, a user who has opted into using a prerelease version has
129 clearly indicated the intent to use that specific set of alpha/beta/rc
130 versions. By including a prerelease tag in the range, the user is in‐
131 dicating that they are aware of the risk. However, it is still not ap‐
132 propriate to assume that they have opted into taking a similar risk on
133 the next set of prerelease versions.
134 Note that this behavior can be suppressed (treating all prerelease ver‐
136 sions as if they were normal versions, for the purpose of range match‐
137 ing) by setting the includePrerelease flag on the options object to any
138 functions https://github.com/npm/node-semver#functions that do range
139 matching.
140 Prerelease Identifiers
142 The method .inc takes an additional identifier string argument that
143 will append the value of the string as a prerelease identifier:
144 semver.inc('1.2.3', 'prerelease', 'beta')
146 // '1.2.4-beta.0'
147 command-line example:
149 $ semver 1.2.3 -i prerelease --preid beta
151 1.2.4-beta.0
152 Which then can be used to increment further:
154 $ semver 1.2.4-beta.0 -i prerelease
156 1.2.4-beta.1
157 Advanced Range Syntax
159 Advanced range syntax desugars to primitive comparators in determinis‐
160 tic ways.
161 Advanced ranges may be combined in the same way as primitive compara‐
163 tors using white space or ||.
164 Hyphen Ranges X.Y.Z - A.B.C
166 Specifies an inclusive set.
167 • 1.2.3 - 2.3.4 := >=1.2.3 <=2.3.4
169 If a partial version is provided as the first version in the inclusive
172 range, then the missing pieces are replaced with zeroes.
173 • 1.2 - 2.3.4 := >=1.2.0 <=2.3.4
175 If a partial version is provided as the second version in the inclusive
178 range, then all versions that start with the supplied parts of the tu‐
179 ple are accepted, but nothing that would be greater than the provided
180 tuple parts.
181 • 1.2.3 - 2.3 := >=1.2.3 <2.4.0
183 • 1.2.3 - 2 := >=1.2.3 <3.0.0
185 X-Ranges 1.2.x 1.X 1.2.* *
188 Any of X, x, or * may be used to "stand in" for one of the numeric val‐
189 ues in the [major, minor, patch] tuple.
190 • * := >=0.0.0 (Any version satisfies)
192 • 1.x := >=1.0.0 <2.0.0 (Matching major version)
194 • 1.2.x := >=1.2.0 <1.3.0 (Matching major and minor versions)
196 A partial version range is treated as an X-Range, so the special char‐
199 acter is in fact optional.
200 • "" (empty string) := * := >=0.0.0
202 • 1 := 1.x.x := >=1.0.0 <2.0.0
204 • 1.2 := 1.2.x := >=1.2.0 <1.3.0
206 Tilde Ranges ~1.2.3 ~1.2 ~1
209 Allows patch-level changes if a minor version is specified on the com‐
210 parator. Allows minor-level changes if not.
211 • ~1.2.3 := >=1.2.3 <1.(2+1).0 := >=1.2.3 <1.3.0
213 • ~1.2 := >=1.2.0 <1.(2+1).0 := >=1.2.0 <1.3.0 (Same as 1.2.x)
215 • ~1 := >=1.0.0 <(1+1).0.0 := >=1.0.0 <2.0.0 (Same as 1.x)
217 • ~0.2.3 := >=0.2.3 <0.(2+1).0 := >=0.2.3 <0.3.0
219 • ~0.2 := >=0.2.0 <0.(2+1).0 := >=0.2.0 <0.3.0 (Same as 0.2.x)
221 • ~0 := >=0.0.0 <(0+1).0.0 := >=0.0.0 <1.0.0 (Same as 0.x)
223 • ~1.2.3-beta.2 := >=1.2.3-beta.2 <1.3.0 Note that prereleases in the
225 1.2.3 version will be allowed, if they are greater than or equal to
226 beta.2. So, 1.2.3-beta.4 would be allowed, but 1.2.4-beta.2 would
227 not, because it is a prerelease of a different [major, minor, patch]
228 tuple.
229 Caret Ranges ^1.2.3 ^0.2.5 ^0.0.4
232 Allows changes that do not modify the left-most non-zero digit in the
233 [major, minor, patch] tuple. In other words, this allows patch and mi‐
234 nor updates for versions 1.0.0 and above, patch updates for versions
235 0.X >=0.1.0, and no updates for versions 0.0.X.
236 Many authors treat a 0.x version as if the x were the major "break‐
238 ing-change" indicator.
239 Caret ranges are ideal when an author may make breaking changes between
241 0.2.4 and 0.3.0 releases, which is a common practice. However, it pre‐
242 sumes that there will not be breaking changes between 0.2.4 and 0.2.5.
243 It allows for changes that are presumed to be additive (but non-break‐
244 ing), according to commonly observed practices.
245 • ^1.2.3 := >=1.2.3 <2.0.0
247 • ^0.2.3 := >=0.2.3 <0.3.0
249 • ^0.0.3 := >=0.0.3 <0.0.4
251 • ^1.2.3-beta.2 := >=1.2.3-beta.2 <2.0.0 Note that prereleases in the
253 1.2.3 version will be allowed, if they are greater than or equal to
254 beta.2. So, 1.2.3-beta.4 would be allowed, but 1.2.4-beta.2 would
255 not, because it is a prerelease of a different [major, minor, patch]
256 tuple.
257 • ^0.0.3-beta := >=0.0.3-beta <0.0.4 Note that prereleases in the
259 0.0.3 version only will be allowed, if they are greater than or equal
260 to beta. So, 0.0.3-pr.2 would be allowed.
261 When parsing caret ranges, a missing patch value desugars to the number
264 0, but will allow flexibility within that value, even if the major and
265 minor versions are both 0.
266 • ^1.2.x := >=1.2.0 <2.0.0
268 • ^0.0.x := >=0.0.0 <0.1.0
270 • ^0.0 := >=0.0.0 <0.1.0
272 A missing minor and patch values will desugar to zero, but also allow
275 flexibility within those values, even if the major version is zero.
276 • ^1.x := >=1.0.0 <2.0.0
278 • ^0.x := >=0.0.0 <1.0.0
280 Range Grammar
283 Putting all this together, here is a Backus-Naur grammar for ranges,
284 for the benefit of parser authors:
285 range-set ::= range ( logical-or range ) *
287 logical-or ::= ( ' ' ) * '||' ( ' ' ) *
288 range ::= hyphen | simple ( ' ' simple ) * | ''
289 hyphen ::= partial ' - ' partial
290 simple ::= primitive | partial | tilde | caret
291 primitive ::= ( '<' | '>' | '>=' | '<=' | '=' ) partial
292 partial ::= xr ( '.' xr ( '.' xr qualifier ? )? )?
293 xr ::= 'x' | 'X' | '*' | nr
294 nr ::= '0' | ['1'-'9'] ( ['0'-'9'] ) *
295 tilde ::= '~' partial
296 caret ::= '^' partial
297 qualifier ::= ( '-' pre )? ( '+' build )?
298 pre ::= parts
299 build ::= parts
300 parts ::= part ( '.' part ) *
301 part ::= nr | [-0-9A-Za-z]+
302
304 All methods and classes take a final options object argument. All op‐
305 tions in this object are false by default. The options supported are:
306 • loose Be more forgiving about not-quite-valid semver strings. (Any
308 resulting output will always be 100% strict compliant, of course.)
309 For backwards compatibility reasons, if the options argument is a
310 boolean value instead of an object, it is interpreted to be the loose
311 param.
312 • includePrerelease Set to suppress the default behavior
314 https://github.com/npm/node-semver#prerelease-tags of excluding pre‐
315 release tagged versions from ranges unless they are explicitly opted
316 into.
317 Strict-mode Comparators and Ranges will be strict about the SemVer
320 strings that they parse.
321 • valid(v): Return the parsed version, or null if it's not valid.
323 • inc(v, release): Return the version incremented by the release type
325 (major, premajor, minor, preminor, patch, prepatch, or prerelease),
326 or null if it's not valid
327 • premajor in one call will bump the version up to the next major
329 version and down to a prerelease of that major version. preminor,
330 and prepatch work the same way.
331 • If called from a non-prerelease version, the prerelease will work
333 the same as prepatch. It increments the patch version, then makes a
334 prerelease. If the input version is already a prerelease it simply
335 increments it.
336 • prerelease(v): Returns an array of prerelease components, or null if
339 none exist. Example: prerelease('1.2.3-alpha.1') -> ['alpha', 1]
340 • major(v): Return the major version number.
342 • minor(v): Return the minor version number.
344 • patch(v): Return the patch version number.
346 • intersects(r1, r2, loose): Return true if the two supplied ranges or
348 comparators intersect.
349 • parse(v): Attempt to parse a string as a semantic version, returning
351 either a SemVer object or null.
352 Comparison
355 • gt(v1, v2): v1 > v2
356 • gte(v1, v2): v1 >= v2
358 • lt(v1, v2): v1 < v2
360 • lte(v1, v2): v1 <= v2
362 • eq(v1, v2): v1 == v2 This is true if they're logically equivalent,
364 even if they're not the exact same string. You already know how to
365 compare strings.
366 • neq(v1, v2): v1 != v2 The opposite of eq.
368 • cmp(v1, comparator, v2): Pass in a comparison string, and it'll call
370 the corresponding function above. "===" and "!==" do simple string
371 comparison, but are included for completeness. Throws if an invalid
372 comparison string is provided.
373 • compare(v1, v2): Return 0 if v1 == v2, or 1 if v1 is greater, or -1
375 if v2 is greater. Sorts in ascending order if passed to Ar‐
376 ray.sort().
377 • rcompare(v1, v2): The reverse of compare. Sorts an array of versions
379 in descending order when passed to Array.sort().
380 • diff(v1, v2): Returns difference between two versions by the release
382 type (major, premajor, minor, preminor, patch, prepatch, or prere‐
383 lease), or null if the versions are the same.
384 Comparators
387 • intersects(comparator): Return true if the comparators intersect
388 Ranges
391 • validRange(range): Return the valid range or null if it's not valid
392 • satisfies(version, range): Return true if the version satisfies the
394 range.
395 • maxSatisfying(versions, range): Return the highest version in the
397 list that satisfies the range, or null if none of them do.
398 • minSatisfying(versions, range): Return the lowest version in the list
400 that satisfies the range, or null if none of them do.
401 • minVersion(range): Return the lowest version that can possibly match
403 the given range.
404 • gtr(version, range): Return true if version is greater than all the
406 versions possible in the range.
407 • ltr(version, range): Return true if version is less than all the ver‐
409 sions possible in the range.
410 • outside(version, range, hilo): Return true if the version is outside
412 the bounds of the range in either the high or low direction. The
413 hilo argument must be either the string '>' or '<'. (This is the
414 function called by gtr and ltr.)
415 • intersects(range): Return true if any of the ranges comparators in‐
417 tersect
418 Note that, since ranges may be non-contiguous, a version might not be
421 greater than a range, less than a range, or satisfy a range! For exam‐
422 ple, the range 1.2 <1.2.9 || >2.0.0 would have a hole from 1.2.9 until
423 2.0.0, so the version 1.2.10 would not be greater than the range (be‐
424 cause 2.0.1 satisfies, which is higher), nor less than the range (since
425 1.2.8 satisfies, which is lower), and it also does not satisfy the
426 range.
427 If you want to know if a version satisfies or does not satisfy a range,
429 use the satisfies(version, range) function.
430 Coercion
432 • coerce(version): Coerces a string to semver if possible
433 This aims to provide a very forgiving translation of a non-semver
436 string to semver. It looks for the first digit in a string, and con‐
437 sumes all remaining characters which satisfy at least a partial semver
438 (e.g., 1, 1.2, 1.2.3) up to the max permitted length (256 characters).
439 Longer versions are simply truncated (4.6.3.9.2-alpha2 becomes 4.6.3).
440 All surrounding text is simply ignored (v3.4 replaces v3.3.1 becomes
441 3.4.0). Only text which lacks digits will fail coercion (version one
442 is not valid). The maximum length for any semver component considered
443 for coercion is 16 characters; longer components will be ignored
444 (10000000000000000.4.7.4 becomes 4.7.4). The maximum value for any
445 semver component is Number.MAX_SAFE_INTEGER || (2**53 - 1); higher
446 value components are invalid (9999999999999999.4.7.4 is likely in‐
447 valid).
448 April 2021 SEMVER(7)