diff options
Diffstat (limited to 'vendor/github.com/Masterminds/semver/v3/README.md')
| -rw-r--r-- | vendor/github.com/Masterminds/semver/v3/README.md | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/vendor/github.com/Masterminds/semver/v3/README.md b/vendor/github.com/Masterminds/semver/v3/README.md new file mode 100644 index 000000000..d8f54dcbd --- /dev/null +++ b/vendor/github.com/Masterminds/semver/v3/README.md @@ -0,0 +1,244 @@ +# SemVer + +The `semver` package provides the ability to work with [Semantic Versions](http://semver.org) in Go. Specifically it provides the ability to: + +* Parse semantic versions +* Sort semantic versions +* Check if a semantic version fits within a set of constraints +* Optionally work with a `v` prefix + +[](https://masterminds.github.io/stability/active.html) +[](https://github.com/Masterminds/semver/actions) +[](https://pkg.go.dev/github.com/Masterminds/semver/v3) +[](https://goreportcard.com/report/github.com/Masterminds/semver) + +If you are looking for a command line tool for version comparisons please see +[vert](https://github.com/Masterminds/vert) which uses this library. + +## Package Versions + +There are three major versions fo the `semver` package. + +* 3.x.x is the new stable and active version. This version is focused on constraint + compatibility for range handling in other tools from other languages. It has + a similar API to the v1 releases. The development of this version is on the master + branch. The documentation for this version is below. +* 2.x was developed primarily for [dep](https://github.com/golang/dep). There are + no tagged releases and the development was performed by [@sdboyer](https://github.com/sdboyer). + There are API breaking changes from v1. This version lives on the [2.x branch](https://github.com/Masterminds/semver/tree/2.x). +* 1.x.x is the most widely used version with numerous tagged releases. This is the + previous stable and is still maintained for bug fixes. The development, to fix + bugs, occurs on the release-1 branch. You can read the documentation [here](https://github.com/Masterminds/semver/blob/release-1/README.md). + +## Parsing Semantic Versions + +There are two functions that can parse semantic versions. The `StrictNewVersion` +function only parses valid version 2 semantic versions as outlined in the +specification. The `NewVersion` function attempts to coerce a version into a +semantic version and parse it. For example, if there is a leading v or a version +listed without all 3 parts (e.g. `v1.2`) it will attempt to coerce it into a valid +semantic version (e.g., 1.2.0). In both cases a `Version` object is returned +that can be sorted, compared, and used in constraints. + +When parsing a version an error is returned if there is an issue parsing the +version. For example, + + v, err := semver.NewVersion("1.2.3-beta.1+build345") + +The version object has methods to get the parts of the version, compare it to +other versions, convert the version back into a string, and get the original +string. Getting the original string is useful if the semantic version was coerced +into a valid form. + +## Sorting Semantic Versions + +A set of versions can be sorted using the `sort` package from the standard library. +For example, + +```go +raw := []string{"1.2.3", "1.0", "1.3", "2", "0.4.2",} +vs := make([]*semver.Version, len(raw)) +for i, r := range raw { + v, err := semver.NewVersion(r) + if err != nil { + t.Errorf("Error parsing version: %s", err) + } + + vs[i] = v +} + +sort.Sort(semver.Collection(vs)) +``` + +## Checking Version Constraints + +There are two methods for comparing versions. One uses comparison methods on +`Version` instances and the other uses `Constraints`. There are some important +differences to notes between these two methods of comparison. + +1. When two versions are compared using functions such as `Compare`, `LessThan`, + and others it will follow the specification and always include prereleases + within the comparison. It will provide an answer that is valid with the + comparison section of the spec at https://semver.org/#spec-item-11 +2. When constraint checking is used for checks or validation it will follow a + different set of rules that are common for ranges with tools like npm/js + and Rust/Cargo. This includes considering prereleases to be invalid if the + ranges does not include one. If you want to have it include pre-releases a + simple solution is to include `-0` in your range. +3. Constraint ranges can have some complex rules including the shorthand use of + ~ and ^. For more details on those see the options below. + +There are differences between the two methods or checking versions because the +comparison methods on `Version` follow the specification while comparison ranges +are not part of the specification. Different packages and tools have taken it +upon themselves to come up with range rules. This has resulted in differences. +For example, npm/js and Cargo/Rust follow similar patterns while PHP has a +different pattern for ^. The comparison features in this package follow the +npm/js and Cargo/Rust lead because applications using it have followed similar +patters with their versions. + +Checking a version against version constraints is one of the most featureful +parts of the package. + +```go +c, err := semver.NewConstraint(">= 1.2.3") +if err != nil { + // Handle constraint not being parsable. +} + +v, err := semver.NewVersion("1.3") +if err != nil { + // Handle version not being parsable. +} +// Check if the version meets the constraints. The a variable will be true. +a := c.Check(v) +``` + +### Basic Comparisons + +There are two elements to the comparisons. First, a comparison string is a list +of space or comma separated AND comparisons. These are then separated by || (OR) +comparisons. For example, `">= 1.2 < 3.0.0 || >= 4.2.3"` is looking for a +comparison that's greater than or equal to 1.2 and less than 3.0.0 or is +greater than or equal to 4.2.3. + +The basic comparisons are: + +* `=`: equal (aliased to no operator) +* `!=`: not equal +* `>`: greater than +* `<`: less than +* `>=`: greater than or equal to +* `<=`: less than or equal to + +### Working With Prerelease Versions + +Pre-releases, for those not familiar with them, are used for software releases +prior to stable or generally available releases. Examples of prereleases include +development, alpha, beta, and release candidate releases. A prerelease may be +a version such as `1.2.3-beta.1` while the stable release would be `1.2.3`. In the +order of precedence, prereleases come before their associated releases. In this +example `1.2.3-beta.1 < 1.2.3`. + +According to the Semantic Version specification prereleases may not be +API compliant with their release counterpart. It says, + +> A pre-release version indicates that the version is unstable and might not satisfy the intended compatibility requirements as denoted by its associated normal version. + +SemVer comparisons using constraints without a prerelease comparator will skip +prerelease versions. For example, `>=1.2.3` will skip prereleases when looking +at a list of releases while `>=1.2.3-0` will evaluate and find prereleases. + +The reason for the `0` as a pre-release version in the example comparison is +because pre-releases can only contain ASCII alphanumerics and hyphens (along with +`.` separators), per the spec. Sorting happens in ASCII sort order, again per the +spec. The lowest character is a `0` in ASCII sort order +(see an [ASCII Table](http://www.asciitable.com/)) + +Understanding ASCII sort ordering is important because A-Z comes before a-z. That +means `>=1.2.3-BETA` will return `1.2.3-alpha`. What you might expect from case +sensitivity doesn't apply here. This is due to ASCII sort ordering which is what +the spec specifies. + +### Hyphen Range Comparisons + +There are multiple methods to handle ranges and the first is hyphens ranges. +These look like: + +* `1.2 - 1.4.5` which is equivalent to `>= 1.2 <= 1.4.5` +* `2.3.4 - 4.5` which is equivalent to `>= 2.3.4 <= 4.5` + +### Wildcards In Comparisons + +The `x`, `X`, and `*` characters can be used as a wildcard character. This works +for all comparison operators. When used on the `=` operator it falls +back to the patch level comparison (see tilde below). For example, + +* `1.2.x` is equivalent to `>= 1.2.0, < 1.3.0` +* `>= 1.2.x` is equivalent to `>= 1.2.0` +* `<= 2.x` is equivalent to `< 3` +* `*` is equivalent to `>= 0.0.0` + +### Tilde Range Comparisons (Patch) + +The tilde (`~`) comparison operator is for patch level ranges when a minor +version is specified and major level changes when the minor number is missing. +For example, + +* `~1.2.3` is equivalent to `>= 1.2.3, < 1.3.0` +* `~1` is equivalent to `>= 1, < 2` +* `~2.3` is equivalent to `>= 2.3, < 2.4` +* `~1.2.x` is equivalent to `>= 1.2.0, < 1.3.0` +* `~1.x` is equivalent to `>= 1, < 2` + +### Caret Range Comparisons (Major) + +The caret (`^`) comparison operator is for major level changes once a stable +(1.0.0) release has occurred. Prior to a 1.0.0 release the minor versions acts +as the API stability level. This is useful when comparisons of API versions as a +major change is API breaking. For example, + +* `^1.2.3` is equivalent to `>= 1.2.3, < 2.0.0` +* `^1.2.x` is equivalent to `>= 1.2.0, < 2.0.0` +* `^2.3` is equivalent to `>= 2.3, < 3` +* `^2.x` is equivalent to `>= 2.0.0, < 3` +* `^0.2.3` is equivalent to `>=0.2.3 <0.3.0` +* `^0.2` is equivalent to `>=0.2.0 <0.3.0` +* `^0.0.3` is equivalent to `>=0.0.3 <0.0.4` +* `^0.0` is equivalent to `>=0.0.0 <0.1.0` +* `^0` is equivalent to `>=0.0.0 <1.0.0` + +## Validation + +In addition to testing a version against a constraint, a version can be validated +against a constraint. When validation fails a slice of errors containing why a +version didn't meet the constraint is returned. For example, + +```go +c, err := semver.NewConstraint("<= 1.2.3, >= 1.4") +if err != nil { + // Handle constraint not being parseable. +} + +v, err := semver.NewVersion("1.3") +if err != nil { + // Handle version not being parseable. +} + +// Validate a version against a constraint. +a, msgs := c.Validate(v) +// a is false +for _, m := range msgs { + fmt.Println(m) + + // Loops over the errors which would read + // "1.3 is greater than 1.2.3" + // "1.3 is less than 1.4" +} +``` + +## Contribute + +If you find an issue or want to contribute please file an [issue](https://github.com/Masterminds/semver/issues) +or [create a pull request](https://github.com/Masterminds/semver/pulls). |