Fix #1545: recur in cond-> gives warning about recur not in tail posi…

…tion.

CHANGELOG.md

@@ -5,6 +5,7 @@ For a list of breaking changes, check [here](#breaking-changes).
 ## Unreleased
 
 - Fix [#1537](https://github.com/clj-kondo/clj-kondo/issues/1537): stackoverflow with potemkin import vars with cyclic references
+- Fix [#1545](https://github.com/clj-kondo/clj-kondo/issues/1545): `recur` in `cond->` gives warning about `recur` not in tail position.
 
 ## 2022.01.13
 

src/clj_kondo/impl/analyzer.clj

@@ -896,6 +896,15 @@
                                   :loop-without-recur "Loop without recur.")))
         analyzed))))
 
+(defn first-callstack-elt-ignoring-macros
+  [callstack]
+  (loop [callstack callstack]
+    (when-let [cse (first callstack)]
+      (if (not (one-of (second cse)
+                       [-> ->> some-> some->> doto cond->]))
+        cse
+        (recur (rest callstack))))))
+
 (defn analyze-recur [ctx expr]
   (let [filename (:filename ctx)
         recur-arity (:recur-arity ctx)
@@ -912,7 +921,7 @@
         (let [len (:len ctx)
               idx (:idx ctx)
               parent (-> (:callstack ctx)
-                         second second)]
+                         rest first-callstack-elt-ignoring-macros second)]
           (when (and len idx
                      (not= (dec len) idx)
                      (not (one-of parent [if case cond if-let if-not condp])))

test/clj_kondo/recur_test.clj

@@ -21,5 +21,6 @@
     (is (empty? (lint! "(loop [] (recur))" linter-config))))
   (testing "recur is in tail position"
     (is (empty? (lint! "(fn [] (if true (recur) 3))" linter-config)))
-    (is (empty? (lint! "(fn [x] (case x 1 (recur (inc x)) 2 :the-end))" linter-config)))))
+    (is (empty? (lint! "(fn [x] (case x 1 (recur (inc x)) 2 :the-end))" linter-config)))
+    (is (empty? (lint! "(loop [x 10] (cond-> (dec x) (pos? x) (recur)))" linter-config)))))