simplify how we lazy load transit. cljs.analyzer/write-analysis-cache now supports

writing out transit if available. cljs.closure/aot-cache-core attempts to write out
transit analysis cache for core. tweak .gitignore now for new cache file.

Author: swannodette

.gitignore

@@ -28,3 +28,4 @@ nashorn_code_cache
 src/main/cljs/cljs/core.aot.js
 src/main/cljs/cljs/core.aot.js.map
 src/main/cljs/cljs/core.cljs.cache.aot.edn
+src/main/cljs/cljs/core.cljs.cache.aot.json

src/main/clojure/cljs/analyzer.cljc

@@ -32,7 +32,7 @@
                      [cljs.tools.reader :as reader]
                      [cljs.tools.reader.reader-types :as readers]
                      [cljs.reader :as edn]))
-  #?(:clj (:import [java.io File Reader PushbackReader]
+  #?(:clj (:import [java.io File Reader PushbackReader FileOutputStream]
                    [java.net URL]
                    [java.lang Throwable]
                    [clojure.lang Namespace Var LazySeq ArityException]
@@ -2818,39 +2818,36 @@
                 (and version (not= version version'))))))))))
 
 #?(:clj
-   (def transit-writer
+   (def transit
      (delay
        (try
          (require '[cognitect.transit])
-         (some->
-           (find-ns 'cognitect.transit)
-           (ns-resolve 'writer)
-           deref)
-         (catch Throwable t
-           nil)))))
-
-#?(:clj
-   (def transit-reader
-     (delay
-       (try
-         (require '[cognitect.transit])
-         (some->
-           (find-ns 'cognitect.transit)
-           (ns-resolve 'reader)
-           deref)
+         (let [ns (find-ns 'cognitect.transit)]
+           (when ns
+             {:writer @(ns-resolve ns 'writer)
+              :reader @(ns-resolve ns 'reader)
+              :write  @(ns-resolve ns 'write)
+              :read   @(ns-resolve ns 'read)}))
          (catch Throwable t
            nil)))))
 
 #?(:clj
    (defn write-analysis-cache
      ([ns cache-file]
        (write-analysis-cache ns cache-file nil))
-     ([ns cache-file src]
+     ([ns ^File cache-file src]
       (util/mkdirs cache-file)
-      (spit cache-file
-        (str ";; Analyzed by ClojureScript " (util/clojurescript-version) "\n"
-          (pr-str
-            (dissoc (get-in @env/*compiler* [::namespaces ns]) :macros))))
+      (let [ext (util/ext cache-file)
+            analysis (dissoc (get-in @env/*compiler* [::namespaces ns]) :macros)]
+        (case ext
+          "edn"  (spit cache-file
+                   (str (when
+                     (str ";; Analyzed by ClojureScript " (util/clojurescript-version) "\n"))
+                       (pr-str analysis)))
+          "json" (when-let [{:keys [writer write]} @transit]
+                   (write
+                     (writer (FileOutputStream. cache-file) :json)
+                     analysis))))
       (when src
         (.setLastModified ^File cache-file (util/last-modified src))))))
 

src/main/clojure/cljs/closure.clj

@@ -2133,14 +2133,16 @@
   (let [base-path (io/file "src" "main" "cljs" "cljs")
         src       (io/file base-path "core.cljs")
         dest      (io/file base-path "core.aot.js")
-        cache     (io/file base-path "core.cljs.cache.aot.edn")]
+        cache     (io/file base-path "core.cljs.cache.aot.edn")
+        tcache    (io/file base-path "core.cljs.cache.aot.json")]
     (util/mkdirs dest)
     (env/with-compiler-env (env/default-compiler-env)
       (comp/compile-file src dest
         {:source-map true
          :source-map-url "core.js.map"
          :output-dir (str "src" File/separator "main" File/separator "cljs")})
-      (ana/write-analysis-cache 'cljs.core cache src))))
+      (ana/write-analysis-cache 'cljs.core cache src)
+      (ana/write-analysis-cache 'cljs.core tcache src))))
 
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