From 6a911fc54f574c9acd2581e7045837448b781afb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Wilker=20L=C3=BAcio?= <wilkerlucio@users.noreply.github.com>
Date: Sat, 13 Mar 2021 12:37:51 -0300
Subject: [PATCH] Augment proxy to fulfill custom maps interfaces (#755)

---
 src/babashka/impl/proxy.clj | 33 ++++++++++++++++++++++++++++-----
 1 file changed, 28 insertions(+), 5 deletions(-)

diff --git a/src/babashka/impl/proxy.clj b/src/babashka/impl/proxy.clj
index fd480745..9a68eaad 100644
--- a/src/babashka/impl/proxy.clj
+++ b/src/babashka/impl/proxy.clj
@@ -8,22 +8,45 @@
   (or (get methods k)
       (throw (UnsupportedOperationException. "Method not implemented: " k))))
 
-(defn proxy-fn [{:keys [:class :methods]}]
+(defn method-or [methods k default]
+  (or (get methods k)
+      default))
+
+(defn proxy-fn [{:keys [class methods]}]
   (case (.getName ^Class class)
     "clojure.lang.APersistentMap"
-    (proxy [clojure.lang.APersistentMap] []
+    (proxy [clojure.lang.APersistentMap clojure.lang.IMeta clojure.lang.IObj] []
       (iterator [] ((method-or-bust methods 'iterator) this))
       (containsKey [k] ((method-or-bust methods 'containsKey) this k))
       (entryAt [k] ((method-or-bust methods 'entryAt) this k))
       (valAt
         ([k] ((method-or-bust methods 'valAt) this k))
         ([k default] ((method-or-bust methods 'valAt) this k default)))
-      (cons [v] ((method-or-bust methods 'cons) this v))
+      (cons [v]
+        (if-let [m (get methods 'cons)]
+          (m this v)
+          (proxy-super cons v)))
       (count [] ((method-or-bust methods 'count) this))
       (assoc [k v] ((method-or-bust methods 'assoc) this k v))
       (without [k] ((method-or-bust methods 'without) this k))
-      (seq [] ((method-or-bust methods 'seq) this)))
+      (seq [] ((method-or-bust methods 'seq) this))
+
+      (equiv [other]
+        (if-let [m (get methods 'equiv)]
+          (m this other)
+          (proxy-super equiv other)))
+      (empty [] ((method-or-bust methods 'empty) this))
+
+      (meta [] ((method-or methods 'meta nil) this))
+      (withMeta [meta] ((method-or methods 'withMeta this) this meta))
+
+      (toString []
+        (if-let [m (get methods 'toString)]
+          (m this)
+          (proxy-super toString))))
     "clojure.lang.AMapEntry"
     (proxy [clojure.lang.AMapEntry] []
       (key [] ((method-or-bust methods 'key) this))
-      (val [] ((method-or-bust methods 'val) this)))))
+      (val [] ((method-or-bust methods 'val) this))
+      (getKey [] ((method-or-bust methods 'getKey) this))
+      (getValue [] ((method-or-bust methods 'getValue) this)))))