build: refresh backend dependencies before bundling

CHANGELOG.md

@@ -7,6 +7,9 @@
 - Add an opt-in Linux `InstallShutdownHook` for SIGTERM/SIGINT. Its
   async-signal-safe self-pipe hands graceful state flushing to a normal watcher
   thread, while a repeated signal still terminates a stuck shutdown.
+- Compile the Racket backend dependency graph with `raco make` before creating
+  `core.zo`, so a same-length edit to a transitive source module cannot leave
+  stale bytecode in a successful native build.
 - Add the Linux tray contract: `rivet::system::TrayIcon` hosts an
   org.kde.StatusNotifierItem with a com.canonical.dbusmenu menu over the
   session bus (GDBus), the pairing every desktop watcher serves (GNOME via

rivet-cli/build.rkt

@@ -154,14 +154,7 @@
   (make-directory* runtime-dir)
 
   (define core (build-path res-dir "core.zo"))
-  (define raco (find-executable-path "raco"))
-  (run! 'build-project!
-        raco
-        "ctool"
-        "--runtime" (path->string runtime-dir)
-        "--runtime-access" "runtime"
-        "--mods" (path->string core)
-        (path->string backend))
+  (compile-backend-module-bundle! backend core runtime-dir)
 
   (for ([source (in-list
                  (list (racket-runtime-petite-boot runtime)
@@ -172,6 +165,24 @@
                     (build-path runtime-dir (file-name-from-path source))))
   core)
 
+(define (compile-backend-module-bundle! backend core [runtime-dir #f])
+  (define raco (find-executable-path "raco"))
+  ;; `raco ctool --mods` can consume an existing compiled entry module without
+  ;; refreshing its transitive dependencies. Compile the dependency graph first
+  ;; so same-length source edits cannot leave stale bytecode in the bundle.
+  (run! 'build-project! raco "make" (path->string backend))
+  (apply run!
+         'build-project!
+         raco
+         "ctool"
+         (append
+          (if runtime-dir
+              (list "--runtime" (path->string runtime-dir)
+                    "--runtime-access" "runtime")
+              '())
+          (list "--mods" (path->string core)
+                (path->string backend)))))
+
 (define (prepare-windows-import-library! project runtime lib-exe)
   (unless lib-exe
     (error 'build-project!
@@ -484,4 +495,5 @@
   (provide copy-project-resources!
            write-app-info!
            required-project-icon
-           prepare-windows-icon-resource!))
+           prepare-windows-icon-resource!
+           compile-backend-module-bundle!))

tests/backend-build.rkt

@@ -0,0 +1,48 @@
+#lang racket/base
+
+(require rackunit
+         racket/file
+         (submod "../rivet-cli/build.rkt" test-support))
+
+(define temp-root (make-temporary-file "rivet-backend-build-~a" 'directory))
+(define dependency-before
+  "#lang racket/base\n(provide value)\n(define value 'before)\n")
+(define dependency-after
+  "#lang racket/base\n(provide value)\n(define value 'after!)\n")
+
+(define (write-module path text)
+  (call-with-output-file path
+    #:exists 'truncate/replace
+    (lambda (out) (display text out))))
+
+(dynamic-wind
+  void
+  (lambda ()
+    (define backend (build-path temp-root "backend.rkt"))
+    (define dependency (build-path temp-root "dependency.rkt"))
+    (define bundle (build-path temp-root "core.zo"))
+    (define compiled-dependency
+      (build-path temp-root "compiled" "dependency_rkt.zo"))
+
+    (write-module backend
+                  "#lang racket/base\n(require \"dependency.rkt\")\n(provide result)\n(define result value)\n")
+    (check-equal? (string-length dependency-before)
+                  (string-length dependency-after))
+    (write-module dependency dependency-before)
+    (compile-backend-module-bundle! backend bundle)
+    (define before (file->bytes compiled-dependency))
+
+    ;; Keep the source length unchanged while making it newer than the cached
+    ;; bytecode, matching the regression reported by a real Rivet application.
+    (write-module dependency dependency-after)
+    (define source-time (file-or-directory-modify-seconds dependency))
+    (for ([compiled (in-list
+                     (list compiled-dependency
+                           (build-path temp-root "compiled" "dependency_rkt.dep")))])
+      (file-or-directory-modify-seconds compiled (sub1 source-time)))
+    (compile-backend-module-bundle! backend bundle)
+
+    (check-not-equal? (file->bytes compiled-dependency) before)
+    (check-true (file-exists? bundle)))
+  (lambda ()
+    (delete-directory/files temp-root)))