From 8d9e15fa0ccb55f09f09f813703b09e259572b94 Mon Sep 17 00:00:00 2001
From: Juan Monetta <jpmonettas@gmail.com>
Date: Sun, 28 Dec 2025 16:11:18 -0300
Subject: [PATCH] CLJS-3469: ClojureScript :preloads doesn't work with just
 cljs.main --repl

---
 src/main/clojure/cljs/cli.clj          | 3 ++-
 src/main/clojure/cljs/repl/browser.clj | 9 +++++++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/main/clojure/cljs/cli.clj b/src/main/clojure/cljs/cli.clj
index da4f2761f..9087151c9 100644
--- a/src/main/clojure/cljs/cli.clj
+++ b/src/main/clojure/cljs/cli.clj
@@ -321,7 +321,8 @@ present"
         reopts (merge repl-env-options (select-keys opts [:main :output-dir]))
         _      (when (or ana/*verbose* (:verbose opts))
                  (util/debug-prn "REPL env options:" (pr-str reopts)))
-        renv   (apply (target->repl-env (:target options) repl-env) (mapcat identity reopts))]
+        renv   (-> (apply (target->repl-env (:target options) repl-env) (mapcat identity reopts))
+                   (assoc :compiler-opts opts))]
     (repl/repl* renv
       (assoc opts
         ::repl/fast-initial-prompt?
diff --git a/src/main/clojure/cljs/repl/browser.clj b/src/main/clojure/cljs/repl/browser.clj
index 2c907c6d1..9b333127e 100644
--- a/src/main/clojure/cljs/repl/browser.clj
+++ b/src/main/clojure/cljs/repl/browser.clj
@@ -182,7 +182,7 @@
 
 (defn send-static
   [{path :path :as request} conn
-   {:keys [static-dir output-dir host port gzip?] :or {output-dir "out"} :as opts}]
+   {:keys [static-dir output-dir host port gzip? compiler-opts] :or {output-dir "out"} :as opts}]
   (let [output-dir (when-not (.isAbsolute (io/file output-dir)) output-dir)]
     (if (and static-dir (not= "/favicon.ico" path))
       (let [path (if (= "/" path) "/index.html" path)
@@ -224,7 +224,11 @@
                                       clojure.browser.repl/PORT ~port}
                                   (merge (:closure-defines @browser-state))
                                   cljsc/normalize-closure-defines
-                                  json/write-str)]
+                                  json/write-str)
+                preloads (when-let [preloads (:preloads compiler-opts)]
+                           (mapv (fn [ns-symb]
+                                   (str "document.write('<script>goog.require(\"" (munge ns-symb) "\");</script>');"))
+                                 preloads))]
             (server/send-and-close conn 200
               (str "var CLOSURE_UNCOMPILED_DEFINES = " closure-defines ";\n"
                    "var CLOSURE_NO_DEPS = true;\n"
@@ -233,6 +237,7 @@
                    (when (.exists (io/file output-dir "cljs_deps.js"))
                      (str "document.write('<script src=\"" output-dir "/cljs_deps.js\"></script>');\n"))
                    "document.write('<script src=\"" output-dir "/brepl_deps.js\"></script>');\n"
+                   (when preloads (str/join "\n" preloads))
                    "document.write('<script>goog.require(\"clojure.browser.repl.preload\");</script>');\n")
               "text/javascript" "UTF-8"))