fix: check if git is present in path (#769)

internal/pipeline/git/errors.go

@@ -1,6 +1,9 @@
 package git
 
-import "fmt"
+import (
+	"errors"
+	"fmt"
+)
 
 // ErrInvalidVersionFormat is return when the version isnt in a valid format
 type ErrInvalidVersionFormat struct {
@@ -31,8 +34,11 @@ func (e ErrWrongRef) Error() string {
 
 // ErrNoTag happens if the underlying git repository doesn't contain any tags
 // but no snapshot-release was requested.
-var ErrNoTag = fmt.Errorf("git doesn't contain any tags. Either add a tag or use --snapshot")
+var ErrNoTag = errors.New("git doesn't contain any tags. Either add a tag or use --snapshot")
 
 // ErrNotRepository happens if you try to run goreleaser against a folder
 // which is not a git repository.
-var ErrNotRepository = fmt.Errorf("current folder is not a git repository")
+var ErrNotRepository = errors.New("current folder is not a git repository")
+
+// ErrNoGit happens when git is not present in PATH.
+var ErrNoGit = errors.New("git not present in PATH")

internal/pipeline/git/git.go

@@ -2,6 +2,7 @@ package git
 
 import (
 	"fmt"
+	"os/exec"
 	"regexp"
 	"strings"
 
@@ -22,6 +23,9 @@ func (Pipe) String() string {
 
 // Run the pipe
 func (Pipe) Run(ctx *context.Context) error {
+	if _, err := exec.LookPath("git"); err != nil {
+		return ErrNoGit
+	}
 	info, err := getInfo(ctx)
 	if err != nil {
 		return err

internal/pipeline/git/git_test.go

@@ -215,3 +215,12 @@ func TestShortCommitHash(t *testing.T) {
 	testlib.AssertSkipped(t, Pipe{}.Run(ctx))
 	assert.Len(t, ctx.Version, 7)
 }
+
+func TestGitNotInPath(t *testing.T) {
+	var path = os.Getenv("PATH")
+	defer func() {
+		assert.NoError(t, os.Setenv("PATH", path))
+	}()
+	assert.NoError(t, os.Setenv("PATH", ""))
+	assert.EqualError(t, Pipe{}.Run(context.New(config.Project{})), ErrNoGit.Error())
+}