Add tests for seq

test/clojure/core_test/seq.cljc

@@ -0,0 +1,30 @@
+(ns clojure.core-test.seq
+  (:require [clojure.test :as t :refer [deftest testing is are]]))
+
+(deftest test-seq
+  ;; Sourced via canSeq https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/RT.java#L581
+  (are [in expected] (= expected (seq in))
+    "test" '(\t \e \s \t)
+    [1 2 3 4] '(1 2 3 4)
+    '(:a :b :c :d) '(:a :b :c :d)
+    '() nil
+    nil nil
+    (sorted-set 3.0 1.0 -2.5 4.0) '(-2.5 1.0 3.0 4.0)
+    (range 5 10) '(5 6 7 8 9)
+    (int-array 3) '(0 0 0))
+  (testing "sets and maps"
+    (let [input #{440M 55000M 80000}
+          input-hash (into (hash-set) input)
+          input-map {:a {:b "4"}
+                     :c 800
+                     nil 40}
+          input-sorted-map (into (sorted-map) input-map)
+          input-hash-map (into (hash-map) input-map)]
+      (is (= input (into #{} (seq input))))
+      (is (= input-hash (into (hash-set) (seq input))))
+      (is (= input-sorted-map (into (sorted-map) (seq input-sorted-map))))
+      (is (= input-hash-map (into (hash-map) (seq input-hash-map))))
+      (is (= input-map (into {} (seq input-map))))))
+  (testing "nonseqables"
+    (is (thrown? IllegalArgumentException (seq 1)))
+    (is (thrown? IllegalArgumentException (seq (fn []))))))