Fail immediately when commands missing

1 files changed, 21 insertions, 0 deletions

diff --git a/internal/exec.go b/internal/exec.go
new file mode 100644
index 0000000..6ed3e5c
--- /dev/null
+++ b/internal/exec.go
@@ -0,0 +1,21 @@
+package internal
+
+import (
+	"fmt"
+	"os/exec"
+)
+
+type CommandNotFound string
+
+func (e CommandNotFound) Error() string {
+	return fmt.Sprintf("command '%s' is missing and must be present for operation", string(e))
+}
+
+func RequireCommand(cmd string) error {
+	_, err := exec.LookPath(cmd)
+	if err != nil {
+		return CommandNotFound(cmd)
+	}
+
+	return nil
+}