Fix #118 - disable unused-ret-vals warnings via config of enclosing-m…

…acros

This by itself seems not to be enough to determine whether it is
inside of (clojure.test/is (thrown? expr)) expression, though, due to
weirdness of clojure.test/is expansion.

resource/config.clj

@@ -278,3 +278,16 @@
   :arglists-for-linting
   '([db table & options])
   :reason "clojure.java.jdbc/insert! uses metadata to override the default value of :arglists for documentation purposes.  This configuration tells Eastwood what the actual :arglists is, i.e. would have been without that."})
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; Notes for warnings to disable in instaparse library, version 1.3.4
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(disable-warning
+ {:linter :unused-ret-vals
+  :for-value nil
+  :if-inside-macroexpansion-of #{'instaparse.gll/dprintln
+                                 'instaparse.gll/debug
+                                 'instaparse.gll/dpprint}
+  :within-depth 1
+  :reason "Instaparse macros debug, dprintln, and dpprint macroexpand to nil if debugging/printing are disabled."})

src/eastwood/linters/unused.clj

@@ -379,7 +379,10 @@ discarded inside null: null'."
                  (if (pass/void-method? (pass/get-method stmt))
                    :side-effect
                    :warn-if-ret-val-unused)
-                 action)]
+                 action)
+        linter (case location
+                 :outside-try :unused-ret-vals
+                 :inside-try :unused-ret-vals-in-try)]
     (if (or (and stmt-in-try-body?
                  (= location :inside-try))
             (and (not stmt-in-try-body?)
@@ -392,9 +395,8 @@ discarded inside null: null'."
 
         (:lazy-fn :pure-fn :pure-fn-if-fn-args-pure :warn-if-ret-val-unused)
         (util/add-loc-info loc
-         {:linter (case location
-                    :outside-try :unused-ret-vals
-                    :inside-try :unused-ret-vals-in-try)
+         {:linter linter
+          linter {:kind (:op stmt), :action action, :ast stmt}
           :msg
           (case action
             :lazy-fn
@@ -487,6 +489,7 @@ discarded inside null: null'."
                        (pass/code-loc (pass/nearest-ast-with-loc stmt))))]
             (util/add-loc-info loc
              {:linter :unused-ret-vals
+              :unused-ret-vals {:kind (:op stmt), :ast stmt}
               :msg (format "%s value is discarded%s: %s"
                            (op-desc (:op stmt))
                            (if name-found?
@@ -519,11 +522,32 @@ discarded inside null: null'."
           (unused-ret-val-lint-result stmt "function call"
                                       action v location)))))))
 
+
+(defn unused-ret-vals* [location {:keys [asts] :as m} opt]
+  (let [warnings (unused-ret-vals-2 location m opt)]
+    (for [w warnings
+          :let [linter (:linter w)
+                info (get w linter)
+                ast (:ast info)
+                allow? (util/allow-warning w opt)]
+          :when allow?]
+      (do
+        (when (:debug-warning opt)
+          ((util/make-msg-cb :debug opt)
+           (with-out-str
+             (println "This warning:")
+             (pp/pprint (dissoc w (:linter w)))
+             (println "was generated from code with the following enclosing macro expansions:")
+             (pp/pprint (->> (util/enclosing-macros ast)
+                             (map #(dissoc % :ast :index)))))))
+        w))))
+
+
 (defn unused-ret-vals [& args]
-  (apply unused-ret-vals-2 :outside-try args))
+  (apply unused-ret-vals* :outside-try args))
 
 (defn unused-ret-vals-in-try [& args]
-  (apply unused-ret-vals-2 :inside-try args))
+  (apply unused-ret-vals* :inside-try args))
 
 
 ;; Unused metadata on macro invocations (depends upon macro

src/eastwood/util.clj

@@ -672,7 +672,10 @@ StringWriter."
                          conj (dissoc m :linter))
               :wrong-arity
               (assoc-in configs [linter (:function-symbol m)]
-                         (dissoc m :linter :function-symbol))))
+                         (dissoc m :linter :function-symbol))
+              (:unused-ret-vals :unused-ret-vals-in-try)
+              (update-in configs [linter]
+                         conj (dissoc m :linter))))
           {} warning-enable-config))
 
 
@@ -755,6 +758,11 @@ StringWriter."
            suppress-conditions opt)))
 
       :constant-test
+      (let [suppress-conditions (get-in opt [:warning-enable-config linter])]
+        (allow-warning-based-on-enclosing-macros
+         w linter "" suppress-conditions opt))
+
+      (:unused-ret-vals :unused-ret-vals-in-try)
       (let [suppress-conditions (get-in opt [:warning-enable-config linter])]
         (allow-warning-based-on-enclosing-macros
          w linter "" suppress-conditions opt)))))