# go-bumpver

_Inspired by the python bump2version tool._

bumpver - print the next semantec version in a given sequence

## Usage

```bash
bumpver part [major|minor|patch] [flags] file [-|file]
```

## Why?

- Most version bumpers are fairly tightly coupled to git
- Make commits for you
- Few have useful pre release mechanisms
- Lack of simple interfaces
- Lack of unix philosophy

## How?

`go-bumpver` takes the sequence of version(s) from a file or stdin and prints the next version. It drops invalid versions in the sequence and only uses valid ones. It does not make a tag or change any state in git or any other VCS, it only prints the next version. It also has the ability to bump pre-release tags using simple formating string.

### Inputs

**stdin**
```bash
❯ echo "1.1.1\n1.2.1" | bumpver patch -
1.2.2
```

**file**
```bash
❯ echo v0.1.0 > VERSION
❯ bumpver patch VERSION
0.1.1
```

**local repo**
```bash
❯ bumpver patch <(git tag -l)
3.3.2
```

**remote repo**
```bash
❯ bumpver patch <(git ls-remote --tags --refs origin v\* | awk -F'[ /]' '{ print $NF }')
3.3.4
```

**bump tags released along a branch**

This example supports software that has support for multiple versions at once. E.g. version 2.X is still supported but 3.X is based off of main.
```bash
❯ bumpver patch <(git tag --merged <release branch name>)
2.1.4
```

### Bumps

**a patch**
```bash
❯ bumpver patch <(git tag -l)
3.3.2
```

**a minor**
```bash
❯ bumpver minor <(git tag -l)
3.4.0
```

**a major**
```bash
❯ bumpver major <(git tag -l)
4.0.0
```

***prior version***
Getting the last version could be useful for generating diffs, release notes etc.

```
❯ bumpver major --last-version <(git tag -l)
3.8.1
❯ bumpver major <(git tag -l)
4.0.0
```


### Pre-release

Pre-releases can be formatted in a way that can be easily bumped. Providing `--prerelease` will generate a new prerelease for the given bump. Meaning if you use `major --prerelease` with the last version 1.2.2 will give `2.0.0-RC.0`.

Use Case:
- A Pull Request/Merge Request is opened. A tag needs to be generated for the PR/MR.
- Bumping release candidates for testing.

#### Format Strings

- `$BumpInt`: increases the integer value.
- `$KeyArg <KEY NAME>`: Value of the key from `key-args` option

#### $BumpInit

Consider the following format string: `rc.$BumpInt`

```bash
❯ echo "0.1.0-rc.1" | bumpver patch --prerelease --prerelease-fmt 'rc.$BumpInt' -
0.1.0-rc.2
```

A none existant pre-release yields

```bash
❯ echo "0.1.0" | bumpver patch --prerelease --prerelease-fmt 'rc.$BumpInt' -
0.1.1-rc.0
```

#### $KeyArg

`$KeyArg` allows for run time side effects on prerelease versions. This means you can bump ain integer or provide key word argument. Examples:
- add the PR/MR number to the version
- add metadata for the version

```bash
❯ bumpver patch --prerelease --prerelease-fmt 'rc.$KeyArg PR_NUM.$BumpInt' --key-args PR_NUM=44 vers.txt
1.2.2-rc.44.0
```