Merge pull request 'The mesh delivers the launcher, which is the last link in self-update' (#56) from feat/142-the-mesh-delivers-the-launcher into main

packaging/launcher_is_delivered_test.go

@@ -0,0 +1,48 @@
+package packaging_test
+
+import (
+	"encoding/json"
+	"os"
+	"testing"
+)
+
+// The mesh delivers the launcher, so the manifest carries a copy of it (novox/hq 04-ISSUES/142).
+//
+// **Two copies of one script is a drift waiting to happen**, and the only reason to accept it is that
+// a file resource is written atomically — temp file, then rename — while an archive writes in place
+// with truncate. The running launcher keeps the inode it was started from and the next start picks up
+// the new one; unpacking an archive over it would truncate the file a running shell is reading.
+//
+// So: two copies, and this is the check that they are the same one.
+func TestTheManifestCarriesTheLauncherExactly(t *testing.T) {
+	onDisk, err := os.ReadFile("nox-mesh-host-launch")
+	if err != nil {
+		t.Fatal(err)
+	}
+	raw, err := os.ReadFile("../module.json")
+	if err != nil {
+		t.Fatal(err)
+	}
+	var manifest struct {
+		Resources []struct {
+			ID      string `json:"id"`
+			Content string `json:"content"`
+		} `json:"resources"`
+	}
+	if err := json.Unmarshal(raw, &manifest); err != nil {
+		t.Fatal(err)
+	}
+	for _, r := range manifest.Resources {
+		if r.ID != "launcher" {
+			continue
+		}
+		if r.Content != string(onDisk) {
+			t.Fatal("the launcher the mesh would deliver is not the launcher in this repository. " +
+				"Copy packaging/nox-mesh-host-launch into module.json's `launcher` resource — the " +
+				"machines run what the manifest says, and this file is what gets reviewed")
+		}
+		return
+	}
+	t.Fatal("module.json declares no `launcher` resource, so nothing delivers the launcher and a " +
+		"delivered host version is never started")
+}