chore(tests): New match-strict? cljs.test directive (#20825)

Equality checks in tests using = give a bad experience by default on test
failures containing nested data structures. We use the cljs.test directive
match? from matcher-combinators library to help compare nested structures. The
problem with match? is that its default matcher for maps (embeds) can be too
permissive, and this causes surprises.

Here we upgrade matcher-combinators to latest, where a new matcher called
nested-equals is available. This matcher won't allow extra keys in maps. This
matcher eliminates the need for manually adding nested equals matchers as we
have to do currently.

- Upgrades matcher-combinators from 3.8.8 to 3.9.1 (latest as of 2024-07-19)

What changes?

When asserting in tests, we now have the option to use match-strict? or match?.
Both directives are available by integrating with cljs.test. The code
implementing the new match-strict? directive was 100% copied from the library
matcher-combinators because we need to wrap the expected value ourselves with
matcher-combinators.matchers/nested-equals. It's ugly code, but it's how we can
integrate with cljs.test/assert-expr.

.clj-kondo/config.edn

@@ -74,7 +74,8 @@
                 ;; https://github.com/borkdude/clj-kondo/issues/867
                 :unresolved-symbol             {:exclude [PersistentPriorityMap.EMPTY
                                                           number
-                                                          legacy.status-im.test-helpers/restore-app-db]}
+                                                          legacy.status-im.test-helpers/restore-app-db
+                                                          (cljs.test/is [match-strict?])]}
                 :unresolved-var                {:level :error}
                 :unsorted-required-namespaces  {:level :error}
                 :unused-alias                  {:level :warning}

nix/deps/clojure/deps.json

@@ -711,11 +711,11 @@
   },
 
   {
-    "path": "nubank/matcher-combinators/3.8.8/matcher-combinators-3.8.8",
+    "path": "nubank/matcher-combinators/3.9.1/matcher-combinators-3.9.1",
     "host": "https://repo.clojars.org",
     "jar": {
-      "sha1": "4c94bd510f0c18a20191e46dd6becedebc640bbd",
+      "sha1": "f0830a112cae8ee931a90d9f39214a0ed4d44150",
-      "sha256": "0wpla2hx0s4mda58ndyd8938zmnz1gyhgfr6pzfphy27xfbvsssl"
+      "sha256": "1rjcgqhms84xmnhs7sqcd3b2dpa37mmzgz2yz33yz2rdb9skl96g"
     }
   },
 

nix/deps/clojure/deps.list

@@ -77,7 +77,7 @@ net/cgrand/macrovich/0.2.1/macrovich-0.2.1.jar
 net/java/dev/jna/jna/5.12.1/jna-5.12.1.jar
 nrepl/bencode/1.1.0/bencode-1.1.0.jar
 nrepl/nrepl/1.0.0/nrepl-1.0.0.jar
-nubank/matcher-combinators/3.8.8/matcher-combinators-3.8.8.jar
+nubank/matcher-combinators/3.9.1/matcher-combinators-3.9.1.jar
 org/apache/ant/ant/1.10.11/ant-1.10.11.jar
 org/apache/ant/ant-launcher/1.10.11/ant-launcher-1.10.11.jar
 org/apache/commons/commons-lang3/3.12.0/commons-lang3-3.12.0.jar

shadow-cljs.edn

@@ -19,7 +19,7 @@
                 [cider/piggieback "0.4.1"]
                 [org.slf4j/slf4j-nop "2.0.9"]
                 [re-frisk-remote "1.6.0"]
-                [nubank/matcher-combinators "3.8.8"]
+                [nubank/matcher-combinators "3.9.1"]
 
                 ;; Use the same version specified in the Nix dependency.
                 [clj-kondo/clj-kondo "2024.03.13"]

src/status_im/contexts/wallet/data_store_test.cljs

@@ -1,7 +1,6 @@
 (ns status-im.contexts.wallet.data-store-test
   (:require
     [cljs.test :refer-macros [deftest is testing]]
-    [matcher-combinators.matchers :as matchers]
     matcher-combinators.test
     [status-im.contexts.wallet.data-store :as sut]))
 
@@ -162,10 +161,7 @@
 (deftest reconcile-keypairs-test
   (testing "reconcile-keypairs represents updated key pairs and accounts"
     (is
-     (match?
+     (match-strict?
-      (matchers/match-with
-       [set? matchers/set-equals
-        map? matchers/equals]
       {:removed-keypair-ids         #{}
        :removed-account-addresses   #{}
        :updated-accounts-by-address {"1x123" (merge account
@@ -189,15 +185,12 @@
                                                                           {:key-uid   "0x456"
                                                                            :address   "1x456"
                                                                            :operable? false
-                                                                            :operable  :no})]}}})
+                                                                           :operable  :no})]}}}
       (sut/reconcile-keypairs [raw-keypair-seed-phrase
                                raw-keypair-private-key]))))
   (testing "reconcile-keypairs represents removed key pairs and accounts"
     (is
-     (match?
+     (match-strict?
-      (matchers/match-with
-       [set? matchers/set-equals
-        map? matchers/equals]
       {:removed-keypair-ids         #{"0x456"}
        :removed-account-addresses   #{"1x456"}
        :updated-accounts-by-address {"1x123" (merge account
@@ -208,15 +201,12 @@
                                               :lowest-operability :fully
                                               :accounts           [(merge account
                                                                           {:key-uid "0x123"
-                                                                            :address "1x123"})]}}})
+                                                                           :address "1x123"})]}}}
       (sut/reconcile-keypairs [raw-keypair-seed-phrase
                                (assoc raw-keypair-private-key :removed true)]))))
   (testing "reconcile-keypairs ignores chat accounts inside updated accounts"
     (is
-     (match?
+     (match-strict?
-      (matchers/match-with
-       [set? matchers/set-equals
-        map? matchers/equals]
       {:removed-keypair-ids         #{}
        :removed-account-addresses   #{}
        :updated-accounts-by-address {"2x000" (merge account
@@ -239,5 +229,5 @@
                                                                            :address          "2x000"
                                                                            :chat             false
                                                                            :wallet           true
-                                                                            :default-account? true})]}}})
+                                                                           :default-account? true})]}}}
       (sut/reconcile-keypairs [raw-keypair-profile])))))

src/test_helpers/matchers.clj

@@ -0,0 +1,47 @@
+(ns test-helpers.matchers
+  "Internal use. Don't require it directly."
+  (:require
+    [cljs.test :as test]
+    [matcher-combinators.core :as core]
+    [matcher-combinators.matchers :as matchers]
+    [matcher-combinators.parser]
+    [matcher-combinators.result :as result]))
+
+;; This implementation is identical to `match?`, but wraps the expected value
+;; with `nested-equals`. This differs from the default `embeds` matcher on maps,
+;; where extra map keys are considered valid.
+(defmethod test/assert-expr 'match-strict?
+  [_ msg form]
+  `(let [args#              (list ~@(rest form))
+         [matcher# actual#] args#]
+     (cond
+       (not (= 2 (count args#)))
+       (test/do-report
+        {:type     :fail
+         :message  ~msg
+         :expected (symbol "`match-strict?` expects 2 arguments: a `matcher` and the `actual`")
+         :actual   (symbol (str (count args#) " were provided: " '~form))})
+
+       (core/matcher? matcher#)
+       (let [result# (core/match (matchers/nested-equals matcher#) actual#)]
+         (test/do-report
+          (if (core/indicates-match? result#)
+            {:type     :pass
+             :message  ~msg
+             :expected '~form
+             :actual   (list 'match? matcher# actual#)}
+            (with-file+line-info
+             {:type     :fail
+              :message  ~msg
+              :expected '~form
+              :actual   (tagged-for-pretty-printing (list '~'not (list 'match? matcher# actual#))
+                                                    result#)
+              :markup   (::result/value result#)}))))
+
+       :else
+       (test/do-report
+        {:type     :fail
+         :message  ~msg
+         :expected (str "The first argument of `match-strict?` "
+                        "needs to be a matcher (implement the match protocol)")
+         :actual   '~form}))))

src/test_helpers/matchers.cljs

@@ -0,0 +1,24 @@
+(ns test-helpers.matchers
+  "Some vars in this namespace solely exist to support the matchers.clj file."
+  (:require-macros test-helpers.matchers)
+  (:require
+    [cljs.test :as t]
+    [matcher-combinators.parser]
+    [matcher-combinators.printer :as printer]
+    [matcher-combinators.result :as result]))
+
+(defrecord Mismatch [summary match-result])
+
+(defn tagged-for-pretty-printing
+  [actual-summary result]
+  (->Mismatch actual-summary result))
+
+(extend-protocol IPrintWithWriter
+ Mismatch
+   (-pr-writer [this writer _]
+     (-write writer (printer/as-string (-> this :match-result ::result/value)))))
+
+(defn with-file+line-info
+  [report]
+  (merge (t/file-and-line (js/Error.) 4)
+         report))

src/test_helpers/unit.cljs

@@ -12,7 +12,10 @@
     [re-frame.events :as rf-events]
     [re-frame.registrar :as rf-registrar]
     [re-frame.subs :as rf-subs]
-    [taoensso.timbre :as log]))
+    [taoensso.timbre :as log]
+
+    ;; We must require this namespace to register the custom cljs.test directive `match-strict?`.
+    test-helpers.matchers))
 
 (defn db
   "A simple wrapper to get the latest value from the app db."