Multimethods

CHANGELOG.md

@@ -4,6 +4,15 @@
 
 ## 0.11.187
 
+- Add multimethod support: `defmulti`, `defmethod`, `get-method`, `methods`,
+  `remove-method`, `remove-all-methods`, `prefer-method`, `prefers`, and
+  hierarchy ops `isa?`, `derive`, `underive`, `make-hierarchy`, `parents`,
+  `ancestors`, `descendants`.
+- `cljs.test/report` is now a multimethod, extensible via `defmethod`:
+  ```
+  (defmethod report [:cljs.test/default :begin-test-var] [m] ...)
+  ```
+  `test-var` now fires `:begin-test-var` / `:end-test-var` events.
 - Accept plain `await` in async functions, in anticipation of CLJS next.
   The legacy `js-await` and `js/await` forms continue to work as
   aliases for now and may be deprecated in a future version.

bb/tasks.clj

@@ -19,7 +19,13 @@
 (defn bump-core-vars []
   (let [core-vars (:out (shell {:out :string}
                                "node --input-type=module -e 'import * as squint from \"squint-cljs/core.js\";console.log(JSON.stringify(Object.keys(squint)))'"))
-        parsed (apply sorted-set (map symbol (json/parse-string core-vars)))]
+        ;; Drop names starting with "__" — convention for
+        ;; exported-but-private helpers (e.g. __toFn) that other runtime
+        ;; modules import but user CLJS shouldn't resolve as a core var.
+        parsed (into (sorted-set)
+                     (comp (remove #(str/starts-with? % "__"))
+                           (map symbol))
+                     (json/parse-string core-vars))]
     (spit "resources/squint/core.edn" (with-out-str
                                         ((requiring-resolve 'clojure.pprint/pprint)
                                          parsed)))))
@@ -87,7 +93,7 @@
     (shell "node" "node_cli.js" "compile" src)
     (let [out (:out (shell {:out :string} "node" out-file))]
       (fs/delete out-file)
-      (assert (str/includes? out "Ran 10 tests containing 20 assertions") out)
+      (assert (str/includes? out "Ran 11 tests containing 21 assertions") out)
       (assert (str/includes? out "1 failures, 0 errors") out)
       ;; :begin-test-ns must fire for each ns visited by run-tests
       (assert (str/includes? out "Testing ns.a") out)

doc/cljs-test-todo.md

@@ -56,13 +56,18 @@ extension point.
 `{op-sym (fn [msg form] ...)}`) that the macro consults. Squint can ship
 the existing four cases as default methods.
 
-### 5. `report` is hardcoded too
-`clojure.test/report` is a multimethod keyed on `:type`; users add
+### 5. `report` is hardcoded too ✅ DONE
+~~`clojure.test/report` is a multimethod keyed on `:type`; users add
 methods to extend reporting (e.g. cljs-test-display). Ours is a single
-`case` defn.
-
-**Fix sketch:** convert to a multimethod (works in squint's runtime; we
-already use `(use-fixtures ...)` etc.).
+`case` defn.~~
+
+Fixed: `report` is now a `defmulti` dispatching on
+`[*current-reporter* (:type m)]`, matching cljs.test. The built-in
+reporter lives under `:cljs.test/default`; unknown combinations fall
+through to a no-op `:default` method. `test-var` now also emits
+`:begin-test-var` / `:end-test-var` so reporters can bracket per-var
+output. Smoke test `report-is-multimethod-test` covers user-defined
+extensions.
 
 ### 6. `test-var` is a plain fn
 `clojure.test/test-var` is a multimethod (`:default` impl is what

package.json

@@ -11,6 +11,7 @@
     "src/squint/set.js",
     "src/squint/html.js",
     "src/squint/math.js",
+    "src/squint/multi.js",
     "src/squint/test.js",
     "lib",
     "node_cli.js",
@@ -61,6 +62,7 @@
     "./src/squint/string.js": "./src/squint/string.js",
     "./node-api.js": "./node-api.js",
     "./src/squint/html.js": "./src/squint/html.js",
+    "./src/squint/multi.js": "./src/squint/multi.js",
     "./src/squint/test.js": "./src/squint/test.js"
   }
 }

playground/bb.edn

@@ -6,7 +6,7 @@
                   (fs/create-sym-link "public/js/squint-local" (fs/parent (fs/parent (fs/absolutize ".")))))
                 (let [squint-prod (fs/file "public" "public" "src" "squint")]
                   (fs/create-dirs squint-prod)
-                  (doseq [source-file ["core.js" "string.js" "set.js" "html.js" "math.js" "test.js"]]
+                  (doseq [source-file ["core.js" "string.js" "set.js" "html.js" "math.js" "multi.js" "test.js"]]
                     (fs/copy (fs/file  ".." "src" "squint" source-file)
                              squint-prod
                              {:replace-existing true}))))}

playground/public/index.html

@@ -18,6 +18,7 @@
           "squint-cljs/src/squint/set.js": "./src/squint/set.js",
           "squint-cljs/src/squint/html.js": "./src/squint/html.js",
           "squint-cljs/src/squint/math.js": "./src/squint/math.js",
+          "squint-cljs/src/squint/multi.js": "./src/squint/multi.js",
           "squint-cljs/src/squint/test.js": "./src/squint/test.js",
           "@codemirror/language": "https://ga.jspm.io/npm:@codemirror/language@6.10.0/dist/index.js",
           "@codemirror/lang-javascript": "https://ga.jspm.io/npm:@codemirror/lang-javascript@6.2.1/dist/index.js",

playground/public/js/main_js.mjs

@@ -108,8 +108,18 @@ let evalCode = async (code) => {
       // opaque origin that can't resolve relative specifiers. Anchor on the
       // page origin — import.meta.url can point to an unexpected bundle path
       // under Vite.
-      const localBase = `${window.location.origin}/js/squint-local/`;
-      js = js.replaceAll("'squint-cljs/", `'${localBase}`);
+      //
+      // Route everything through /src/squint/ (matching the importmap) so
+      // user-compiled code and the runtime modules (test.js, multi.js) end
+      // up importing the SAME URL for core.js. Previously user code went
+      // via /js/squint-local/core.js → Vite-transformed shim →
+      // /@fs/.../src/squint/core.js, while the runtime's bare specifier
+      // resolved via the importmap to /src/squint/core.js — two URLs,
+      // two ES-module instances, two _metaSym symbols, and with-meta
+      // written through one was invisible to meta in the other.
+      const base = `${window.location.origin}/src/squint/`;
+      js = js.replaceAll("'squint-cljs/src/squint/", `'${base}`);
+      js = js.replaceAll("'squint-cljs/", `'${base}`);
     }
     JSEditor(js);
     if (!repl) {

resources/squint/core.edn

@@ -14,7 +14,6 @@
   _LT__EQ_
   _PLUS_
   _STAR_
-  __protocol_satisfies
   _iterator
   abs
   aclone

src/squint/compiler.cljc

@@ -24,6 +24,7 @@
    [squint.internal.fn :refer [core-defmacro core-defn core-defn- core-fn]]
    [squint.internal.loop :as loop]
    [squint.internal.macros :as macros]
+   [squint.internal.multi :as multi]
    [squint.internal.protocols :as protocols]
    [squint.internal.test :as test])
   #?(:cljs (:require-macros [squint.resource :refer [edn-resource]])))
@@ -103,7 +104,22 @@
                              'assoc macros/assoc-inline
                              'assoc! macros/assoc!-inline
                              'get macros/get-inline
-                             'vswap! macros/vswap!}
+                             'vswap! macros/vswap!
+                             'defmulti multi/core-defmulti
+                             'defmethod multi/core-defmethod
+                             'get-method multi/core-get-method
+                             'methods multi/core-methods
+                             'remove-method multi/core-remove-method
+                             'remove-all-methods multi/core-remove-all-methods
+                             'prefer-method multi/core-prefer-method
+                             'prefers multi/core-prefers
+                             'isa? multi/core-isa?
+                             'derive multi/core-derive
+                             'underive multi/core-underive
+                             'make-hierarchy multi/core-make-hierarchy
+                             'parents multi/core-parents
+                             'ancestors multi/core-ancestors
+                             'descendants multi/core-descendants}
                             cc/common-macros))
 
 (def built-in-macro-nss
@@ -452,6 +468,7 @@
                cc/*repl* (:repl opts cc/*repl*)]
        (let [core-package (get import-maps cc/*core-package* cc/*core-package*)
              need-html-import (atom false)
+             need-multi-import (atom false)
              opts (merge {:ns-state (atom {})
                           :top-level true} opts)
              imported-vars (atom {})
@@ -478,7 +495,8 @@
                                                         :imports imports
                                                         :jsx false
                                                         :pragmas pragmas
-                                                        :need-html-import need-html-import))
+                                                        :need-html-import need-html-import
+                                                        :need-multi-import need-multi-import))
                  jsx *jsx*
                  _ (when (and jsx jsx-runtime)
                      (swap! imports str
@@ -500,6 +518,13 @@
                                 (if cc/*repl*
                                   (format "var squint_html = await import('%s');\n" html-pkg)
                                   (format "import * as squint_html from '%s';\n" html-pkg)))))
+                 _ (when @need-multi-import
+                     (swap! imports str
+                            (let [multi-pkg "squint-cljs/src/squint/multi.js"
+                                  multi-pkg (get import-maps multi-pkg multi-pkg)]
+                                (if cc/*repl*
+                                  (format "var squint_multi = await import('%s');\n" multi-pkg)
+                                  (format "import * as squint_multi from '%s';\n" multi-pkg)))))
                  pragmas (:js @pragmas)
                  imports (when-not elide-imports @imports)
                  exports (when-not elide-exports