Test that a fill the node-engine failed is tried again when its socket returns (issue 1873)

modules/mesh-provisioner-client/cmd/mesh-provisioner-client/socket_integration_test.go

@@ -106,3 +106,38 @@ func TestWatchSocketWakesWhenTheSocketIsMadeAndWhenItsDirectoryReturns(t *testin
 	defer l.Close()
 	heard("the directory and socket back")
 }
+
+// Issue 1873: a fill the node-engine refused for a reason of its own (on ace, "read …/superuser.secret: is a
+// directory", what a container runtime had left there) is tried again when a node-engine makes its socket again, as a
+// newer engine may write what the older could not. Before, only a fill that failed for want of the socket was, so
+// ace's postgres stayed unplaced after the engine that cures it was delivered, and its old failure was said every 30 s.
+func TestNatsAFillTheEngineFailedIsTriedWhenTheSocketReturns(t *testing.T) {
+	b := startBus(t)
+	heard := b.listen(t)
+	e := newEngine(t, map[string]string{dunstrc: "owned"})
+	if err := os.MkdirAll(e.at(dunstrc), 0o755); err != nil {
+		t.Fatal(err)
+	}
+	stop := e.listen(t)
+	b.config(t, "dunst", "font-size", "13")
+	b.assign(t, "dunst", dunst(t))
+	aClient(t, b, e, t.TempDir())
+
+	eventually(t, "the engine's failure is said", func() bool {
+		r, _ := heard.last("dunst")
+		return r.Status == StatusFailed && strings.Contains(r.Reason, "is a directory")
+	})
+	// The node-engine replaces itself with one that clears what the runtime left.
+	stop()
+	if err := os.Remove(e.at(dunstrc)); err != nil {
+		t.Fatal(err)
+	}
+	e.listen(t)
+	eventually(t, "dunstrc is written by the new engine", func() bool {
+		return strings.Contains(e.read(t, dunstrc), "Monospace 13")
+	})
+	eventually(t, "and the report says applied", func() bool {
+		r, _ := heard.last("dunst")
+		return r.Status == StatusApplied
+	})
+}