Add pre & post conditions for all functions

chbrown · Jun 5, 2018 · 9e24b3f · 9e24b3f
1 parent b34ef2c
commit 9e24b3f
Showing 1 changed file with 28 additions and 0 deletions.
diff --git a/src/jurl/core.cljc b/src/jurl/core.cljc
@@ -9,13 +9,17 @@
   "URL-encode `string`; other implementations sometimes convert '+' to '%20',
   but this method does not. Uses UTF-8 as the encoding if applicable."
   [string]
+  {:pre [(or (nil? string) (string? string))]
+   :post [(string? %)]}
   (-> (str string)
       #?(:clj  (java.net.URLEncoder/encode "UTF-8")
          :cljs (js/encodeURIComponent))))
 
 (defn ^:export decode
   "URL-decode `string`. Uses UTF-8 as the encoding if applicable."
   [string]
+  {:pre  [(or (nil? string) (string? string))]
+   :post [(string? %)]}
   (-> (str string)
       #?(:clj  (java.net.URLDecoder/decode "UTF-8")
          :cljs (js/decodeURIComponent))))
@@ -34,6 +38,9 @@
   ; TODO: define how to handle non-tuple parameters
   ; TODO: consider using URLSearchParams when more browsers support it.
   [search]
+  {:pre  [(string? search)]
+   :post [(every? string? (map first %))
+          (every? string? (map second %))]}
   (when-not (empty? search)
     (->> (str/split (subs search 1) #"&")
          ; (str/split "" #"&") returns [""], but we would prefer []
@@ -43,6 +50,8 @@
 (defn- update-conj
   "Add v to the (maybe empty) vector at (get m k)"
   [m [k v]]
+  {:pre  [(map? m)]
+   :post [(contains? % k)]}
   ; we don't use update since that doesn't allow a default for missing values
   ; if we didn't mind the ordering we could just use (update m k conj v)
   ; but this way the order of the vector matches the order of the values
@@ -53,6 +62,8 @@
   ([search]
    (search->map search nil))
   ([search {re :split}]
+   {:pre  [(string? search)]
+    :post [(map? %)]}
    (reduce update-conj {} (cond->> (search->seq search)
                             ; when {:split re} is supplied, produce a [k v] pair for each split substring of v
                             re (mapcat (fn [[k v]] (map vector (repeat k) (str/split v re))))))))
@@ -62,6 +73,10 @@
 (defn ^:export seq->search
   "Serialize a seq of key-value tuples back into a string"
   [kvs]
+  {:pre  [(or (nil? kvs) (coll? kvs))
+          (every? string? (map first kvs))
+          (every? string? (map second kvs))]
+   :post [(or (nil? %) (string? %))]}
   (some->> kvs
            (map #(str/join "=" %))
            (str/join "&")
@@ -70,6 +85,8 @@
 (defn- map-values
   "Construct a new map with all the values of the given map passed through f"
   [f kvs]
+  {:pre  [(ifn? f) (map? kvs)]
+   :post [(map? %)]}
   (into (empty kvs) (for [[k v] kvs] [k (f v)])))
 
 (defn- ungroup
@@ -79,6 +96,12 @@
   ([m]
    (ungroup nil m))
   ([separator m]
+   {:pre  [(or (nil? separator) (string? separator))
+           (map? m)
+           (every? string? (keys m))
+           (every? string? (apply concat (vals m)))]
+    :post [(every? string? (map first %))
+           (every? string? (map second %))]}
    (if separator
      (for [[k vs] m]
        [k (str/join separator vs)])
@@ -92,4 +115,9 @@
   ([m]
    (map->search m nil))
   ([m {:keys [separator]}]
+   {:pre  [(or (nil? m) (map? m))
+           (every? string? (keys m))
+           (every? string? (apply concat (vals m)))
+           (or (nil? separator) (string? separator))]
+    :post [(or (nil? %) (string? %))]}
    (some->> m (map-values #(map encode %)) (ungroup separator) seq->search)))