Merge pull request #45 from pitch-io/fix-mocking-again

Correctly reset original binding values when using `setup-mocks`

changelog.md

@@ -1,5 +1,11 @@
 # Changelog
 
+# 1.1.4
+
+## Bugfixes
+
+- [Fix `setup-mocks` and `with-mocks` regression when resetting to the original bindings.](https://github.com/pitch-io/cljest/pull/45)
+
 # 1.1.3
 
 This version and 1.1.2 have no user facing changes except that they make the `cljdoc` build work completely, as in `1.1.1` while the analysis worked, the docs didn't.

cljest/build.edn

@@ -1,5 +1,5 @@
 {:lib com.pitch/cljest
- :version "1.1.3"
+ :version "1.1.4"
  :scm {:url "https://github.com/pitch-io/cljest"
        :connection "scm:git:git://github.com/pitch-io/cljest.git"
        :developerConnection "scm:git:[email protected]:pitch-io/cljest.git"}

cljest/src/cljest/helpers/core.clj

@@ -5,18 +5,32 @@
   "Similar to `with-redefs` but allows arbitrarily beginning and ending when the bindings are mocked and reset by calling
   `start` and `finish` respectively."
   [start finish bindings & body]
-  (let [names (take-nth 2 bindings)
-        vals (take-nth 2 (drop 1 bindings))
-        wrapped-vals (map (fn [v] (list 'fn [] v)) vals)
-        orig-val-syms (for [_ names] (gensym))
-        temp-val-syms (for [_ names] (gensym))
-        binds (map vector names temp-val-syms)
-        redefs (reverse (map vector names orig-val-syms))
+  (let [original-syms (take-nth 2 bindings)
+        orig-vals (take-nth 2 (drop 1 bindings))
+
+        ;; Wrap the values in a function so that they get recreated on each call. This
+        ;; prevents something stateful from "keeping" its state in multiple test cases.
+        wrapped-orig-vals (map (fn [v] (list 'fn [] v)) orig-vals)
+
+        ;; Generate new symbols for both the original values and the
+        ;; temporary values
+        orig-val-syms (for [_ original-syms] (gensym))
+        temp-val-syms (for [_ original-syms] (gensym))
+
+        ;; Create new vectors that sets the original symbols to the temporary ones
+        mocked-binds (map vector original-syms temp-val-syms)
+
+        ;; Put the bindings back. Use the same function call method as above to mimic
+        ;; how we handle mocks
+        orig-binds (reverse (map (fn [name v] [name (list 'fn [] v)]) original-syms orig-val-syms))
+
+        ;; The actual `(set! sym (val))`. It calls whatever `v` it, so the values need
+        ;; to be wrapped in a function to allow for that.
         bind-value (fn [[k v]] (list 'set! k (list v)))]
-    `(let [~@(interleave orig-val-syms names)
-           ~@(interleave temp-val-syms wrapped-vals)
-           ~start #(do ~@(map bind-value binds))
-           ~finish #(do ~@(map bind-value redefs))]
+    `(let [~@(interleave orig-val-syms original-syms)
+           ~@(interleave temp-val-syms wrapped-orig-vals)
+           ~start #(do ~@(map bind-value mocked-binds))
+           ~finish #(do ~@(map bind-value orig-binds))]
        ~@body)))
 
 (defmacro setup-mocks

cljest/src/cljest/helpers/core_test.cljs

@@ -31,6 +31,14 @@
         (swap! counter dec)
         @counter)))
 
+  ;; The presence of this function validates mocking the symbol
+  ;; doesn't cause the function to be called. See https://github.com/pitch-io/cljest/issues/44
+  ;; The same could be done with a primitive value that can't be `.call`-ed, but this
+  ;; will show a nicer error.
+  (defn ^:private my-super-cool-fn
+    []
+    (throw (js/Error. "This function should never be called!")))
+
   (h/setup-mocks [something-stateful (let [counter (atom 0)]
                                        (fn []
                                          (swap! counter (partial + 2))
@@ -39,7 +47,9 @@
                   something-else-stateful (let [counter (atom 0)]
                                             (fn []
                                               (swap! counter #(- % 2))
-                                              @counter))])
+                                              @counter))
+
+                  my-super-cool-fn (constantly nil)])
 
   (it "works"
     (is (= 2 (something-stateful)))

jest-preset-cljest/package.json

@@ -1,6 +1,6 @@
 {
   "name": "jest-preset-cljest",
-  "version": "1.1.3",
+  "version": "1.1.4",
   "description": "A preset for Jest to allow compiling ClojureScript tests",
   "main": "jest-preset.js",
   "scripts": {},