add: gui and tsdiag

gui/util.go

@@ -0,0 +1,20 @@
+package gui
+
+import (
+	"runtime"
+	"time"
+)
+
+// runtimeInfo describes the host, for diagnostic bundle headers.
+func runtimeInfo() string {
+	return runtime.GOOS + "/" + runtime.GOARCH + " go" + runtime.Version()[2:]
+}
+
+// timeSince is time.Since, wrapped so tests can reason about it and so call
+// sites in layout code read consistently.
+func timeSince(t time.Time) time.Duration {
+	if t.IsZero() {
+		return 0
+	}
+	return time.Since(t)
+}