Fossil Forum

The new fossil whatis -h flag is most welcome and will doubtless replace many local hand-rolled alternatives. However, if you're using Go, you don't need to call fossil manually at all. Given this main.go:

package main

import (
    "flag"
    "fmt"
    "os"
    "runtime/debug"
)

var Version string

func getVCSInfo() string {
    if info, ok := debug.ReadBuildInfo(); ok {
        for _, s := range info.Settings {
            if s.Key == "vcs.revision" {
                rev := s.Value
                if len(rev) >= 10 {
                    return "[" + rev[:10] + "]"
                }
                return "[" + rev + "]"
            }
        }
    }
    return "UNKNOWN"
}

func main() {
    showVersion := flag.Bool("version", false, "show version and exit")
    flag.Parse()

    if *showVersion {
        if Version != "" {
            fmt.Println(Version)
        } else {
            fmt.Println(getVCSInfo())
        }
        os.Exit(0)
    }

    fmt.Println("go-fsl-version demo")
}

…and this go.mod:

module go-fsl-version

go 1.21

…and this Makefile:

VERSION ?= 0.1.0

build:
    go build -o go-fsl-version .

release:
    go build -ldflags "-X main.Version=$(VERSION)" -o go-fsl-version .

.PHONY: build release

…you can now pull off stunts like these:

$ make && ./go-fsl-version -version
UNKNOWN
$ fossil init ../go-fsl-version.fossil
$ fossil open -f ../go-fsl-version.fossil
$ make && ./go-fsl-version -version
[6927174644]
$ make release && ./go-fsl-version -version
0.1.0
$ VERSION=0.2.0-beta1 make release && ./go-fsl-version -version
0.2.0-beta1

Now your release builds are tagged with the VERSION from the Makefile — which can be manually overridden as we see in the last command — but pre-release builds are tagged with a 10-digit prefix of the commit that produced them. Z ebc4eb6