From 236dca28d95a70d25b53bb7f085687f62b9cdb16 Mon Sep 17 00:00:00 2001
From: Yogthos <yogthos@gmail.com>
Date: Sun, 14 Jun 2026 23:00:48 -0400
Subject: [PATCH] satisfies? recognizes reify, consistent with instance?
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A reify's protocol methods are instance-local, so they aren't in the global type
registry that type-satisfies? consults — satisfies? returned false for a reify
even when it implemented the protocol. Check the protocols the reify records on
itself (the same :jolt/protocols list instance? uses), matching short names like
instance? does. Covers single- and multi-protocol reify.
---
 src/jolt/evaluator.janet       | 18 +++++++++++++-----
 test/spec/protocols-spec.janet |  6 ++++++
 2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/src/jolt/evaluator.janet b/src/jolt/evaluator.janet
index 524e472..3cebf84 100644
--- a/src/jolt/evaluator.janet
+++ b/src/jolt/evaluator.janet
@@ -1725,16 +1725,24 @@
         (let [tbl (get mm-var :jolt/methods)]
           (when tbl (each k (keys tbl) (set m (phm-assoc m k (get tbl k))))))
         m)))
-  # satisfies?: evaluated protocol value + instance (matches the prior arm).
+  # satisfies?: evaluated protocol value + instance. Recognizes a reify the same
+  # way instance? does — by the protocols it records on itself (a reify's methods
+  # are instance-local, so they aren't in the global type registry that
+  # type-satisfies? consults).
   (ns-intern core "satisfies?"
     (fn [proto obj]
+      (def pn (proto :name))
+      (def pn-str (if (struct? pn) (pn :name) pn))
+      (def protos (if (table? obj) (get obj :jolt/protocols)))
       (def type-tag (or (record-tag obj)
                         (if (and (table? obj) (get obj :jolt/protocol-methods))
                           (get obj :jolt/deftype))))
-      (if type-tag
-        (let [pn (proto :name)
-              pn-str (if (struct? pn) (pn :name) pn)]
-          (type-satisfies? ctx type-tag pn-str))
+      (cond
+        (and protos (string? pn-str)
+             (truthy? (some (fn [p] (= (last (string/split "." p))
+                                       (last (string/split "." pn-str))))
+                            protos))) true
+        type-tag (type-satisfies? ctx type-tag pn-str)
         false)))
   # instance?: the overlay macro passes the TYPE NAME quoted (class names don't
   # evaluate to values on jolt); the value arg arrives evaluated.
diff --git a/test/spec/protocols-spec.janet b/test/spec/protocols-spec.janet
index b6606cf..b14a723 100644
--- a/test/spec/protocols-spec.janet
+++ b/test/spec/protocols-spec.janet
@@ -42,6 +42,12 @@
    "(do (defprotocol P (m [_])) (defrecord R [] P (m [_] 1)) (satisfies? P (->R)))"]
   ["satisfies? false"     "false"
    "(do (defprotocol P (m [_])) (defrecord R []) (satisfies? P (->R)))"]
+  ["satisfies? reify"     "true"
+   "(do (defprotocol P (m [_])) (satisfies? P (reify P (m [_] 1))))"]
+  ["satisfies? reify multi-protocol" "[true true]"
+   "(do (defprotocol P (m [_])) (defprotocol Q (n [_])) (let [r (reify P (m [_] 1) Q (n [_] 2))] [(satisfies? P r) (satisfies? Q r)]))"]
+  ["satisfies? reify other proto" "false"
+   "(do (defprotocol P (m [_])) (defprotocol Q (n [_])) (satisfies? Q (reify P (m [_] 1))))"]
   ["instance? record"     "true"
    "(do (defrecord R [a]) (instance? R (->R 1)))"]
   ["dot constructor"      "5"