CLJS-3401: dedupe '+ and '_PLUS symbols with :optimize-constants (#203)

Co-authored-by: Michiel Borkent <michielborkent@gmail.com>

Author: swannodette

src/main/clojure/cljs/analyzer.cljc

@@ -513,14 +513,16 @@
                  (symbol? value)  "cst$sym$"
                  :else
                  (throw
-                   #?(:clj (Exception. (str "constant type " (type value) " not supported"))
-                      :cljs (js/Error. (str "constant type " (type value) " not supported")))))
+                  #?(:clj (Exception. (str "constant type " (type value) " not supported"))
+                     :cljs (js/Error. (str "constant type " (type value) " not supported")))))
         name   (if (keyword? value)
                  (subs (str value) 1)
                  (str value))
         name   (if (= "." name)
                  "_DOT_"
                  (-> name
+                     (string/replace "_" "__")
+                     (string/replace "$" "$$")
                      (string/replace "-" "_DASH_")
                      (munge)
                      (string/replace "." "$")

src/test/clojure/cljs/analyzer_tests.clj

@@ -1512,3 +1512,9 @@
                     (Foo. nil nil)))))
     (is (= 1 (count @ws)))
     (is (string/starts-with? (first @ws) "Wrong number of args (2) passed to Foo"))))
+
+(deftest test-cljs-3401
+  (is (not= (ana/gen-constant-id '_PLUS_)
+            (ana/gen-constant-id '+)))
+  (is (not= (ana/gen-constant-id 'foo.bar)
+            (ana/gen-constant-id 'foo$bar))))