Add minimal reify

CHANGELOG.md

@@ -6,6 +6,7 @@
 
 - Fix [#815](https://github.com/squint-cljs/squint/issues/815): `str` wrapping known-numeric infix expressions in `??''`, which esbuild flagged as `suspicious-nullish-coalescing`.
 - Fix [#820](https://github.com/squint-cljs/squint/issues/820): `:macros` option silently ignored when passed to `compileString` / `compileStringEx` from JavaScript callers (string keys were keyword-ized by `clj-ize-opts` and no longer matched the symbol-keyed macro lookups in `compile*`).
+- [#817](https://github.com/squint-cljs/squint/issues/817): add minimal `reify`
 
 ## 0.11.189
 

src/squint/compiler.cljc

@@ -87,6 +87,7 @@
                              'defprotocol protocols/core-defprotocol
                              'extend-type protocols/core-extend-type
                              'extend-protocol protocols/core-extend-protocol
+                             'reify protocols/core-reify
                              'deftype deftype/core-deftype
                              'defn core-defn
                              'defn- core-defn-

src/squint/internal/protocols.cljc

@@ -156,3 +156,11 @@
         (bar [x y] ...)))"
   [_ _ p & specs]
   (emit-extend-protocol p specs))
+
+(core/defn core-reify
+  [_ _ & impls]
+  (core/let [t (gensym "t_reify_")]
+    `(do
+       (deftype ~t []
+         ~@impls)
+       (new ~t))))

test/squint/compiler_test.cljs

@@ -558,11 +558,11 @@
                      (bar (->Foo) 1 2))))))
 
 (deftest satisfies?-test
-  #_#_(is (jsv! '(do (defprotocol IFoo)
-                     (satisfies? (reify IFoo)))))
+  (is (jsv! '(do (defprotocol IFoo)
+                 (satisfies? IFoo (reify IFoo)))))
   (is (jsv! '(do (defprotocol IFoo (-foo [_]))
-                 (satisfies? (reify IFoo
-                               (-foo [_] "bar"))))))
+                 (satisfies? IFoo (reify IFoo
+                                    (-foo [_] "bar"))))))
   (is (jsv! '(do (defprotocol IFoo)
                  (deftype Foo [] IFoo)
                  (satisfies? IFoo (->Foo)))))
@@ -576,6 +576,35 @@
                  (extend-type string IFoo)
                  (satisfies? IFoo "bar")))))
 
+(deftest reify-test
+  (is (jsv! '(do (defprotocol IFoo (-foo [_]))
+                 (defprotocol IBar (-bar [_]))
+                 (let [r (reify IFoo (-foo [_] :foo)
+                                IBar (-bar [_] :bar))]
+                   (and (satisfies? IFoo r) (satisfies? IBar r))))))
+  (is (= "b" (jsv! '(do (defprotocol IFoo (-foo [_]) (-bar [_]))
+                        (-foo (reify IFoo
+                                (-foo [this] (-bar this))
+                                (-bar [_] "b")))))))
+  (is (eq #js [10 20 30]
+          (jsv! '(do (defprotocol IFoo (-foo [_]))
+                     (let [xs [10 20 30]]
+                       (mapv (fn [x] (-foo (reify IFoo (-foo [_] x))))
+                             xs))))))
+  (is (true? (jsv! '(do (defprotocol P
+                          (a? [h])
+                          (b? [h])
+                          (c [h]))
+                        (defn mk-p [v]
+                          (reify P
+                            (a? [_] true)
+                            (b? [_] false)
+                            (c [_] v)))
+                        (let [h (mk-p :foo)]
+                          (and (a? h)
+                               (not (b? h))
+                               (= :foo (c h)))))))))
+
 (deftest set-test
   (is (eq (js/Set. #js [1 2 3]) (jsv! #{1 2 3})))
   (is (eq (js/Set. [1 2 3]) (jsv! '(set [1 2 3]))))