Add --version flag

.github/workflows/prerelease.yml

@@ -28,7 +28,9 @@ jobs:
           go-version: '1.26.3'
 
       - name: Build binaries
-        run: make release
+        run: |
+          SHORT_SHA=$(git rev-parse --short HEAD)
+          make release VERSION="pre-release-$SHORT_SHA"
 
       - name: Create Release and Upload Assets
         env:

.github/workflows/release.yml

@@ -29,7 +29,9 @@ jobs:
           go-version: '1.26.3'
 
       - name: Build binaries
-        run: make release
+        run: |
+          TAG_NAME=${GITHUB_REF#refs/tags/}
+          make release VERSION="$TAG_NAME"
 
       - name: Create Release and Upload Assets
         env:

Makefile

@@ -1,5 +1,7 @@
 .DEFAULT_GOAL := build
 .PHONY: clean fmt vet lint build run release
+VERSION ?= $(shell git describe --tags --always --dirty 2>/dev/null || echo dev)
+LDFLAGS := -s -w -X github.com/DataDog/ddtest/internal/buildinfo.Version=$(VERSION)
 clean:
 	go clean -i -x
 fmt:
@@ -11,14 +13,14 @@ lint: vet
 test:
 	go test ./...
 build: test lint
-	go build -o ddtest main.go
+	go build -ldflags="$(LDFLAGS)" -o ddtest main.go
 run:
 	go run main.go
 release:
 	mkdir -p dist
-	GOOS=linux GOARCH=amd64 go build -ldflags="-s -w" -o dist/ddtest-linux-amd64 main.go
-	GOOS=linux GOARCH=arm64 go build -ldflags="-s -w" -o dist/ddtest-linux-arm64 main.go
-	GOOS=darwin GOARCH=amd64 go build -ldflags="-s -w" -o dist/ddtest-darwin-amd64 main.go
-	GOOS=darwin GOARCH=arm64 go build -ldflags="-s -w" -o dist/ddtest-darwin-arm64 main.go
-	GOOS=windows GOARCH=amd64 go build -ldflags="-s -w" -o dist/ddtest-windows-amd64.exe main.go
-	GOOS=windows GOARCH=arm64 go build -ldflags="-s -w" -o dist/ddtest-windows-arm64.exe main.go
+	GOOS=linux GOARCH=amd64 go build -ldflags="$(LDFLAGS)" -o dist/ddtest-linux-amd64 main.go
+	GOOS=linux GOARCH=arm64 go build -ldflags="$(LDFLAGS)" -o dist/ddtest-linux-arm64 main.go
+	GOOS=darwin GOARCH=amd64 go build -ldflags="$(LDFLAGS)" -o dist/ddtest-darwin-amd64 main.go
+	GOOS=darwin GOARCH=arm64 go build -ldflags="$(LDFLAGS)" -o dist/ddtest-darwin-arm64 main.go
+	GOOS=windows GOARCH=amd64 go build -ldflags="$(LDFLAGS)" -o dist/ddtest-windows-amd64.exe main.go
+	GOOS=windows GOARCH=arm64 go build -ldflags="$(LDFLAGS)" -o dist/ddtest-windows-arm64.exe main.go

internal/buildinfo/version.go

@@ -0,0 +1,26 @@
+package buildinfo
+
+import "runtime/debug"
+
+const defaultVersion = "dev"
+
+// Version is set by release builds with -ldflags.
+var Version = defaultVersion
+
+func CurrentVersion() string {
+	if Version != "" && Version != defaultVersion {
+		return Version
+	}
+
+	if info, ok := debug.ReadBuildInfo(); ok {
+		if info.Main.Version != "" && info.Main.Version != "(devel)" {
+			return info.Main.Version
+		}
+	}
+
+	if Version != "" {
+		return Version
+	}
+
+	return defaultVersion
+}

internal/buildinfo/version_test.go

@@ -0,0 +1,29 @@
+package buildinfo
+
+import "testing"
+
+func TestCurrentVersionUsesInjectedVersion(t *testing.T) {
+	originalVersion := Version
+	t.Cleanup(func() {
+		Version = originalVersion
+	})
+
+	Version = "v1.2.3"
+
+	if got := CurrentVersion(); got != "v1.2.3" {
+		t.Fatalf("expected injected version, got %q", got)
+	}
+}
+
+func TestCurrentVersionFallsBackToDefault(t *testing.T) {
+	originalVersion := Version
+	t.Cleanup(func() {
+		Version = originalVersion
+	})
+
+	Version = ""
+
+	if got := CurrentVersion(); got != defaultVersion {
+		t.Fatalf("expected default version, got %q", got)
+	}
+}

internal/cmd/cmd.go

@@ -6,7 +6,9 @@ import (
 	"log/slog"
 	"os"
 
+	"github.com/DataDog/ddtest/internal/buildinfo"
 	"github.com/DataDog/ddtest/internal/constants"
+	"github.com/DataDog/ddtest/internal/git"
 	"github.com/DataDog/ddtest/internal/runner"
 	"github.com/DataDog/ddtest/internal/settings"
 	"github.com/spf13/cobra"
@@ -17,9 +19,13 @@ import (
 var defaultParallelism = settings.DefaultParallelism()
 
 var rootCmd = &cobra.Command{
-	Use:   "ddtest",
-	Short: "A test runner from Datadog",
-	Long:  "Command line tool for running tests with Datadog Test Optimization.",
+	Use:     "ddtest",
+	Short:   "A test runner from Datadog",
+	Long:    "Command line tool for running tests with Datadog Test Optimization.",
+	Version: buildinfo.CurrentVersion(),
+	PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
+		return git.CheckAvailable()
+	},
 }
 
 var planCmd = &cobra.Command{
@@ -55,6 +61,8 @@ var runCmd = &cobra.Command{
 }
 
 func init() {
+	rootCmd.SetVersionTemplate("{{ .Version }}\n")
+
 	rootCmd.PersistentFlags().String("platform", "ruby", "Platform that runs tests")
 	rootCmd.PersistentFlags().String("framework", "rspec", "Test framework to use")
 	rootCmd.PersistentFlags().Int("min-parallelism", defaultParallelism, "Minimum number of parallel test processes (default: number of physical CPUs)")

internal/cmd/cmd_test.go

@@ -2,10 +2,12 @@ package cmd
 
 import (
 	"bytes"
+	"errors"
 	"os"
 	"strings"
 	"testing"
 
+	"github.com/DataDog/ddtest/internal/git"
 	"github.com/DataDog/ddtest/internal/settings"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
@@ -134,6 +136,42 @@ func TestExecute(t *testing.T) {
 	}
 }
 
+func TestVersionFlag(t *testing.T) {
+	resetBoolFlag := func(name string) {
+		if rootCmd.Flags().Lookup(name) != nil {
+			_ = rootCmd.Flags().Set(name, "false")
+		}
+	}
+	resetBoolFlag("help")
+	resetBoolFlag("version")
+
+	originalLookPathFunc := git.LookPathFunc
+	git.LookPathFunc = func(file string) (string, error) {
+		return "", errors.New("git should not be checked for --version")
+	}
+	t.Cleanup(func() {
+		git.LookPathFunc = originalLookPathFunc
+		resetBoolFlag("help")
+		resetBoolFlag("version")
+		rootCmd.SetArgs(nil)
+		rootCmd.SetOut(os.Stdout)
+		rootCmd.SetErr(os.Stderr)
+	})
+
+	var buf bytes.Buffer
+	rootCmd.SetOut(&buf)
+	rootCmd.SetErr(&buf)
+	rootCmd.SetArgs([]string{"--version"})
+
+	if err := Execute(); err != nil {
+		t.Fatalf("Execute() with --version should not return error, got %v", err)
+	}
+
+	if got, want := buf.String(), rootCmd.Version+"\n"; got != want {
+		t.Fatalf("expected version output %q, got %q", want, got)
+	}
+}
+
 func TestFlagBinding(t *testing.T) {
 	// Reset viper
 	viper.Reset()

main.go

@@ -5,15 +5,9 @@ import (
 	"os"
 
 	"github.com/DataDog/ddtest/internal/cmd"
-	"github.com/DataDog/ddtest/internal/git"
 )
 
 func main() {
-	if err := git.CheckAvailable(); err != nil {
-		slog.Error(err.Error())
-		os.Exit(1)
-	}
-
 	// it doesn't make sense to use ddtest without test optimization mode,
 	// so we just enable it
 	_ = os.Setenv("DD_CIVISIBILITY_ENABLED", "1")