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Module

std/semver/mod.ts

Deno standard library
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import * as mod from "https://deno.land/std@0.202.0/semver/mod.ts";

The semantic version parser.

Adapted directly from semver.

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.

Format

Semantic versions can be formatted as strings, by default they are formatted as full. Below is a diagram showing the various formatting options.

          ┌───── full
      ┌───┴───┐
      ├───────── release
  ┌───┴───┐   │
  ├───────────── primary
┌─┴─┐     │   │
1.2.3-pre.1+b.1
│ │ │ └─┬─┘ └┬┘
│ │ │   │    └── build
│ │ │   └─────── pre
│ │ └─────────── patch
│ └───────────── minor
└─────────────── major

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 .increment takes an additional identifier string argument that will append the value of the string as a prerelease identifier:

semver.increment(parse("1.2.3"), "prerelease", "beta");
// "1.2.4-beta.0"

Build Metadata

Build metadata is . delimited alpha-numeric string. When parsing a version it is retained on the build: string[] field of the semver instance. When incrementing there is an additional parameter that can set the build metadata on the semver instance.

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 element 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 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.
  • ^0.0.3-beta := >=0.0.3-beta <0.0.4 Note that prereleases in the 0.0.3 version only will be allowed, if they are greater than or equal to beta. 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 " - " partial
simple     ::= primitive | partial | tilde | caret
primitive  ::= ( "<" | ">" | ">=" | "<=" | "=" ) partial
partial    ::= xr ( "." xr ( "." xr qualifier ? )? )?
xr         ::= "x" | "X" | "*" | nr
nr         ::= "0" | ["1"-"9"] ( ["0"-"9"] ) *
tilde      ::= "~" partial
caret      ::= "^" partial
qualifier  ::= ( "-" pre )? ( "+" build )?
pre        ::= parts
build      ::= parts
parts      ::= part ( "." part ) *
part       ::= nr | [-0-9A-Za-z]+

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 function.

This module is browser compatible.

Examples

Example 1

import {
  parse,
  parseComparator,
  parseRange,
  gt,
  lt,
  format
} from "https://deno.land/std@0.202.0/semver/mod.ts";

const semver = parse("1.2.3");
const range = parseRange("1.x || >=2.5.0 || 5.0.0 - 7.2.3");

const s0 = parse("1.2.3");
const s1 = parse("9.8.7");
gt(s0, s1); // false
lt(s0, s1); // true

format(semver) // "1.2.3"

Variables

A comparator which will span all valid semantic versions

ANY is a sentinel value used by some range calculations. It is not a valid SemVer object and should not be used directly.

A sentinel value used to denote an invalid SemVer object which may be the result of impossible ranges or comparator operations.

MAX is a sentinel value used by some range calculations. It is equivalent to ∞.∞.∞.

The minimum valid SemVer object. Equivalent to 0.0.0.

A comparator which will not span any semantic versions

Functions

Do a comparison of two semantic version objects based on the given operator

Formats the comparator into a string

Returns true if the range of possible versions intersects with the other comparators set of possible versions

The maximum version that could match this comparator.

The minimum semantic version that could match this comparator

Compare two semantic version objects.

Compare two semantic version objects including build metadata.

Returns difference between two versions by the release type, or undefined if the versions are the same.

Returns true if they're logically equivalent, even if they're not the exact same version object.

Format a SemVer object into a string.

Greater than comparison

Greater than or equal to comparison

Checks to see if the version is greater than all possible versions of the range.

Returns the new version resulting from an increment by release type.

Checks to see if value is a valid SemVer object. It does a check into each field including prerelease and build.

Does a deep check on the value to see if it is a valid SemVerComparator object.

Does a deep check on the object to determine if its a valid range.

Less than comparison

Less than or equal to comparison

Greater than range comparison

Returns the highest version in the list that satisfies the range, or undefined if none of them do.

Returns the lowest version in the list that satisfies the range, or undefined if none of them do.

Not equal comparison

Returns true if the version is outside the bounds of the range in either the high or low direction. The hilo argument must be either the string '>' or '<'. (This is the function called by gtr and ltr.)

Attempt to parse a string as a semantic version, returning either a SemVer object or throws a TypeError.

Parses a comparator string into a valid SemVerComparator.

Parses a range string into a SemVerRange object or throws a TypeError.

Formats the range into a string

The ranges intersect every range of AND comparators intersects with a least one range of OR ranges.

The maximum valid SemVer for a given range or INVALID

The minimum valid SemVer for a given range or INVALID

A reverse comparison of two versions. Same as compare but 1 and -1 are inverted.

Sorts a list of semantic versions in descending order.

Sorts a list of semantic versions in ascending order.

Test to see if a semantic version falls within the range of the comparator.

Test to see if the version satisfies the range.

Interfaces

A SemVer object parsed into its constituent parts.

The shape of a valid semantic version comparator

A type representing a semantic version range. The ranges consist of a nested array, which represents a set of OR comparisons while the inner array represents AND comparisons.

Type Aliases

The style to use when formatting a SemVer object into a string

SemVer comparison operators.

The possible release types are used as an operator for the increment function and as a result of the difference function.