Raise a module's unhealthy urgent when its manifest says why (hq ADR 0355, issue 691)

A broken service people rely on, such as mail, was said only as a warning on
the desktop. A module may now declare unhealthy urgent with what people lose;
the module check refuses it without why or with another severity.

internal/catalogue/unhealthy_test.go

@@ -0,0 +1,53 @@
+package catalogue
+
+import (
+	"strings"
+	"testing"
+)
+
+// A module may declare its unhealthy urgent, with why; the module check refuses it without why and with any
+// severity but urgent or warning (novox/hq ADR 0355).
+
+func TestAnUnhealthyDeclaredUrgentIsUrgent(t *testing.T) {
+	m, err := ParseManifest([]byte(`{"module":"mail","version":"1",` +
+		`"unhealthy":{"severity":"urgent","why":"mail is refused or stuck for everyone with a mailbox"}}`))
+	if err != nil {
+		t.Fatalf("a manifest declaring its unhealthy urgent with why was refused: %v", err)
+	}
+	if !m.UnhealthyIsUrgent() {
+		t.Errorf("a manifest declaring its unhealthy urgent reads as not urgent: %+v", m.Unhealthy)
+	}
+}
+
+func TestAManifestWithoutUnhealthyIsNotUrgent(t *testing.T) {
+	m, err := ParseManifest([]byte(`{"module":"notes","version":"1"}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if m.UnhealthyIsUrgent() {
+		t.Errorf("a manifest saying nothing of its unhealthy reads as urgent")
+	}
+	warning := Manifest{Module: "notes", Unhealthy: &UnhealthyPolicy{Severity: UnhealthyWarning, Why: "notes wait"}}
+	if warning.UnhealthyIsUrgent() || len(warning.unhealthyProblems()) != 0 {
+		t.Errorf("a warning said with why reads as urgent or is refused: %v", warning.unhealthyProblems())
+	}
+}
+
+func TestAnUnhealthyWithoutWhyIsRefused(t *testing.T) {
+	for _, why := range []string{"", "   "} {
+		if problems := (Manifest{Module: "mail", Unhealthy: &UnhealthyPolicy{Severity: UnhealthyUrgent, Why: why}}).unhealthyProblems(); len(problems) == 0 {
+			t.Errorf("urgent with why %q was accepted", why)
+		}
+	}
+	if _, err := ParseManifest([]byte(`{"module":"mail","version":"1","unhealthy":{"severity":"urgent"}}`)); err == nil ||
+		!strings.Contains(err.Error(), "unhealthy says why") {
+		t.Errorf("a manifest declaring its unhealthy urgent without why parsed: %v", err)
+	}
+}
+
+func TestAnUnhealthySeverityOtherThanUrgentOrWarningIsRefused(t *testing.T) {
+	if _, err := ParseManifest([]byte(`{"module":"mail","version":"1","unhealthy":{"severity":"loud","why":"mail stops"}}`)); err == nil ||
+		!strings.Contains(err.Error(), `not "loud"`) {
+		t.Errorf("a manifest declaring its unhealthy loud parsed: %v", err)
+	}
+}