CLJS-2352: Emit valid JS for NaN etc. even when used w/ CLJ >= 1.9.0-alpha20

Author: athos

src/main/clojure/cljs/compiler.cljc

@@ -248,9 +248,24 @@
    (defmethod emit-constant Integer [x] (emits x))) ; reader puts Integers in metadata
 
 #?(:clj
-   (defmethod emit-constant Double [x] (emits x))
+   (defmethod emit-constant Double [x]
+     (let [x (double x)]
+       (cond (Double/isNaN x)
+             (emits "NaN")
+
+             (Double/isInfinite x)
+             (emits (if (pos? x) "Infinity" "-Infinity"))
+
+             :else (emits x))))
    :cljs
-   (defmethod emit-constant js/Number [x] (emits "(" x ")")))
+   (defmethod emit-constant js/Number [x]
+     (cond (js/isNaN x)
+           (emits "NaN")
+
+           (not (js/isFinite x))
+           (emits (if (pos? x) "Infinity" "-Infinity"))
+
+           :else (emits "(" x ")"))))
 
 #?(:clj
    (defmethod emit-constant BigDecimal [x] (emits (.doubleValue ^BigDecimal x))))

src/test/clojure/cljs/compiler_tests.clj

@@ -65,6 +65,16 @@
              (ana/analyze (assoc aenv :context :expr) 'js/-Infinity)))
           "-Infinity")))
 
+(deftest test-cljs-2352
+  (are [form result]
+      (= (with-out-str
+           (comp/emit
+             (ana/analyze (assoc aenv :context :expr) form)))
+         result)
+    Double/NaN "##NaN"
+    Double/POSITIVE_INFINITY "##Inf"
+    Double/NEGATIVE_INFINITY "##-Inf"))
+
 (deftest test-munge-dotdot
   (is (= 'cljs.core._DOT__DOT_ (comp/munge 'cljs.core/..)))
   (is (= "cljs.core._DOT__DOT_" (comp/munge "cljs.core/..")))