Lint against incorrect transient usage (#442)

* Lint against incorrect transient usage Closes #441
jonase · Sep 14, 2022 · d289d06 · d289d06
1 parent caf8720
commit d289d06
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diff --git a/README.md b/README.md
@@ -41,7 +41,7 @@ Eastwood can be run from the command line as a
 Merge the following into your `project.clj` or `~/.lein/profiles.clj`:
 
 ```clojure
-:plugins [[jonase/eastwood "1.2.5"]]
+:plugins [[jonase/eastwood "1.3.0"]]
 ```
 
 To run Eastwood with the default set of lint warnings on all of the
@@ -60,7 +60,7 @@ If you're using `deps.edn`, you can set Eastwood options in an edn map, like thi
                  "eastwood.lint"
                  ;; Any Eastwood options can be passed here as edn:
                  {}]
-     :extra-deps {jonase/eastwood {:mvn/version "1.2.5"}}}}}
+     :extra-deps {jonase/eastwood {:mvn/version "1.3.0"}}}}}
 
 ```
 to your `deps.edn`, and you should then be able to run Eastwood as
@@ -421,7 +421,7 @@ If you use Leiningen, merge this into your project's `project.clj`
 file first:
 
 ```clojure
-:profiles {:dev {:dependencies [[jonase/eastwood "1.2.5" :exclusions [org.clojure/clojure]]]}}
+:profiles {:dev {:dependencies [[jonase/eastwood "1.3.0" :exclusions [org.clojure/clojure]]]}}
 ```
 
 If you use a different build tool, you will need to add the dependency
@@ -564,7 +564,7 @@ can be used to modify this merging behavior.
 For example, if your user-wide `profiles.clj` file contains this:
 
 ```clojure
-{:user {:plugins [[jonase/eastwood "1.2.5"]]
+{:user {:plugins [[jonase/eastwood "1.3.0"]]
         :eastwood {:exclude-linters [:unlimited-use]
                    :debug [:time]}
         }}
@@ -2202,7 +2202,7 @@ your local Maven repository:
     $ cd path/to/eastwood
     $ lein with-profile -user,-dev,+eastwood-plugin install
 
-Then add `[jonase/eastwood "1.2.5"]` to
+Then add `[jonase/eastwood "1.3.0"]` to
 your `:plugins` vector in your `:user` profile, perhaps in your
 `$HOME/.lein/profiles.clj` file.
 

diff --git a/cases/testcases/unused_ret_vals/red5.clj b/cases/testcases/unused_ret_vals/red5.clj
@@ -0,0 +1,18 @@
+(ns testcases.unused-ret-vals.red5
+  "https://github.com/jonase/eastwood/issues/441")
+
+(defn bad1 [x]
+  (conj! x 2)
+  42)
+
+(defn bad2 [x]
+  (assoc! x :a 2)
+  42)
+
+(defn bad3 [x]
+  (pop! x)
+  42)
+
+(defn bad4 [x]
+  (dissoc! x :a)
+  42)
diff --git a/changes.md b/changes.md
@@ -1,4 +1,11 @@
-## Changes from 1.2.5 to 1.2.5
+## Changes from 1.2.5 to 1.3.0
+
+#### New
+
+* Lint against incorrect usage of transients.
+  * Closes https://github.com/jonase/eastwood/issues/441
+
+## Changes from 1.2.4 to 1.2.5
 
 #### Bugfixes
 

diff --git a/project.clj b/project.clj
@@ -64,8 +64,8 @@
                                                   [metosin/spec-tools "0.10.5"]
                                                   [org.clojure/core.async "1.5.648"]
                                                   [org.clojure/java.jdbc "0.7.12"]]}
-             :clj-kondo {:dependencies [[clj-kondo "2022.08.03"]]}
-             :antq {:plugins [[com.github.liquidz/antq "2.0.889"]]
+             :clj-kondo {:dependencies [[clj-kondo "2022.09.08"]]}
+             :antq {:plugins [[com.github.liquidz/antq "2.0.895"]]
                     :antq {:exclude ["nrepl/nrepl" "org.clojure/clojure"]}}
              :1.7 {:dependencies [[org.clojure/clojure "1.7.0"]]}
              :1.8 {:dependencies [[org.clojure/clojure "1.8.0"]]}

diff --git a/resource/var-info.edn b/resource/var-info.edn
@@ -139,7 +139,8 @@
  clojure.core/assert {:var-kind nil, :macro true},
  clojure.core/assert-same-protocol {:var-kind nil, :macro nil, :side-effect true},
  clojure.core/assoc {:var-kind nil, :macro nil, :lazy false, :pure-fn true},
- clojure.core/assoc! {:var-kind nil, :macro nil, :predicate false, :side-effect true, :pure-fn false, :warn-if-ret-val-unused false, :lazy false, :pure-if-fn-args-pure false, :io-fn false, :evals-exprs false},
+ ;; `:warn-if-ret-val-unused true` because "transients are not designed to be bashed in-place" (https://clojure.org/reference/transients):
+ clojure.core/assoc! {:var-kind nil, :macro nil, :predicate false, :side-effect false, :pure-fn false, :warn-if-ret-val-unused true, :lazy false, :pure-if-fn-args-pure false, :io-fn false, :evals-exprs false},
  clojure.core/assoc-in {:var-kind nil, :macro nil, :lazy false, :pure-fn true},
  clojure.core/associative? {:var-kind nil, :macro nil, :lazy false, :pure-fn true, :predicate true},
  clojure.core/atom {:var-kind nil, :macro nil},
@@ -210,7 +211,8 @@
  clojure.core/cond->> {:var-kind nil, :macro true},
  clojure.core/condp {:var-kind nil, :macro true},
  clojure.core/conj {:var-kind nil, :macro nil, :lazy false, :pure-fn true},
- clojure.core/conj! {:var-kind nil, :macro nil, :predicate false, :side-effect true, :pure-fn false, :warn-if-ret-val-unused false, :lazy false, :pure-if-fn-args-pure false, :io-fn false, :evals-exprs false},
+ ;; `:warn-if-ret-val-unused true` because "transients are not designed to be bashed in-place" (https://clojure.org/reference/transients):
+ clojure.core/conj! {:var-kind nil, :macro nil, :predicate false, :side-effect false, :pure-fn false, :warn-if-ret-val-unused true, :lazy false, :pure-if-fn-args-pure false, :io-fn false, :evals-exprs false},
  clojure.core/cons {:var-kind nil, :macro nil, :lazy false, :pure-fn true},
  clojure.core/constantly {:var-kind nil, :macro nil, :pure-if-fn-args-pure true},
  clojure.core/construct-proxy {:var-kind nil, :macro nil},
@@ -248,7 +250,8 @@
  clojure.core/disj {:var-kind nil, :macro nil, :lazy false, :pure-fn true},
  clojure.core/disj! {:var-kind nil, :macro nil, :predicate false, :side-effect true, :pure-fn false, :warn-if-ret-val-unused false, :lazy false, :pure-if-fn-args-pure false, :io-fn false, :evals-exprs false},
  clojure.core/dissoc {:var-kind nil, :macro nil, :lazy false, :pure-fn true},
- clojure.core/dissoc! {:var-kind nil, :macro nil, :predicate false, :side-effect true, :pure-fn false, :warn-if-ret-val-unused false, :lazy false, :pure-if-fn-args-pure false, :io-fn false, :evals-exprs false},
+ ;; `:warn-if-ret-val-unused true` because "transients are not designed to be bashed in-place" (https://clojure.org/reference/transients):
+ clojure.core/dissoc! {:var-kind nil, :macro nil, :predicate false, :side-effect false, :pure-fn false, :warn-if-ret-val-unused true, :lazy false, :pure-if-fn-args-pure false, :io-fn false, :evals-exprs false},
  clojure.core/distinct {:var-kind nil, :macro nil, :lazy false, :pure-fn true},
  clojure.core/distinct? {:var-kind nil, :macro nil, :lazy false, :pure-fn true, :predicate true},
  clojure.core/doall {:var-kind nil, :macro nil, :predicate false, :side-effect true :pure-fn false :warn-if-ret-val-unused false :lazy false, :pure-if-fn-args-pure false :io-fn false :evals-exprs false}, ;; TBD: Consider making a special warning just for this one, suggesting to use dorun instead if the return value is not needed, potentially saving memory
@@ -447,7 +450,8 @@
  clojure.core/persistent! {:var-kind nil, :macro nil, :predicate false, :side-effect true, :pure-fn false, :warn-if-ret-val-unused false, :lazy false, :pure-if-fn-args-pure false, :io-fn false, :evals-exprs false},
  clojure.core/pmap {:var-kind nil, :macro nil, :lazy true, :pure-fn-if-fn-args-pure true},
  clojure.core/pop {:var-kind nil, :macro nil, :lazy false, :pure-fn true},
- clojure.core/pop! {:var-kind nil, :macro nil, :predicate false, :side-effect true, :pure-fn false, :warn-if-ret-val-unused false, :lazy false, :pure-if-fn-args-pure false, :io-fn false, :evals-exprs false},
+ ;; `:warn-if-ret-val-unused true` because "transients are not designed to be bashed in-place" (https://clojure.org/reference/transients):
+ clojure.core/pop! {:var-kind nil, :macro nil, :predicate false, :side-effect false, :pure-fn false, :warn-if-ret-val-unused true, :lazy false, :pure-if-fn-args-pure false, :io-fn false, :evals-exprs false},
  clojure.core/pop-thread-bindings {:var-kind nil, :macro nil},
  clojure.core/pos? {:var-kind nil, :macro nil, :lazy false, :pure-fn true, :predicate true},
  clojure.core/pr {:var-kind nil, :macro nil, :io-fn true, :side-effect true},

diff --git a/resources/EASTWOOD_VERSION b/resources/EASTWOOD_VERSION
@@ -1,5 +1,5 @@
 {
  :major 1
- :minor 2
- :patch 5
+ :minor 3
+ :patch 0
 }
diff --git a/test/eastwood/lint_test.clj b/test/eastwood/lint_test.clj
@@ -462,7 +462,18 @@ See https://github.com/jonase/eastwood/issues/402"
       #{'testcases.unused-ret-vals.red1}   {:some-warnings true}
       #{'testcases.unused-ret-vals.red2}   {:some-warnings true}
       #{'testcases.unused-ret-vals.red3}   {:some-warnings true}
-      #{'testcases.unused-ret-vals.red4}   {:some-warnings true})))
+      #{'testcases.unused-ret-vals.red4}   {:some-warnings true}))
+
+  (testing "Transients"
+    (let [^String s (with-out-str
+                      (-> sut/default-opts
+                          (assoc :namespaces #{'testcases.unused-ret-vals.red5})
+                          (sut/eastwood)))]
+      (is (-> s (.contains
+                 "cases/testcases/unused_ret_vals/red5.clj:5:3: unused-ret-vals {:kind :invoke}: Should use return value of function call, but it is discarded: (conj! x 2).
+cases/testcases/unused_ret_vals/red5.clj:9:3: unused-ret-vals {:kind :invoke}: Should use return value of function call, but it is discarded: (assoc! x :a 2).
+cases/testcases/unused_ret_vals/red5.clj:13:3: unused-ret-vals {:kind :invoke}: Should use return value of function call, but it is discarded: (pop! x).
+cases/testcases/unused_ret_vals/red5.clj:17:3: unused-ret-vals {:kind :invoke}: Should use return value of function call, but it is discarded: (dissoc! x :a)."))))))
 
 (deftest reflection
   (are [desc input expected] (testing input