clj-kondo#2031: Fix NPE when importing string (clj-kondo#2205)

CHANGELOG.md

@@ -17,6 +17,10 @@ For a list of breaking changes, check [here](#breaking-changes).
 <!-- - [ ] update lein-clj-kondo -->
 <!-- - [ ] update carve -->
 
+## Unreleased
+
+- [#2013](https://github.com/clj-kondo/clj-kondo/issues/2013): Fix NPE and similar errors when linting an import with an illegal token
+
 ## 2023.10.20
 
 - [#1804](https://github.com/clj-kondo/clj-kondo/issues/1804): new linter `:self-requiring-namespace`

src/clj_kondo/impl/analyzer/namespace.clj

@@ -342,12 +342,21 @@
                               :syntax "Expected: package name followed by classes.")))
                       (into {} (for [i imported]
                                  [i java-package])))
-    :token (let [package+class (:value libspec-expr)
-                 splitted (-> package+class name (str/split #"\."))
-                 java-package (symbol (str/join "." (butlast splitted)))
-                 imported (with-meta (symbol (last splitted))
-                            (meta libspec-expr))]
-             {imported java-package})
+    :token (if (symbol? (:value libspec-expr))
+             (let [package+class (:value libspec-expr)
+                   splitted (-> package+class name (str/split #"\."))
+                   java-package (symbol (str/join "." (butlast splitted)))
+                   imported (with-meta (symbol (last splitted))
+                              (meta libspec-expr))]
+               {imported java-package})
+             (do
+               (findings/reg-finding!
+                ctx
+                (node->line
+                 (:filename ctx)
+                 libspec-expr
+                 :syntax "Import target is not a package"))
+               {}))
     nil))
 
 (defn analyze-require-clauses [ctx ns-name kw+libspecs]

test/clj_kondo/main_test.clj

@@ -3420,6 +3420,12 @@ foo/")))
   (is (= "error" (:fail-level (#'clj-kondo.main/parse-opts ["--fail-level" "error"]))))
   (is (= "error" (:fail-level (#'clj-kondo.main/parse-opts ["--fail-level=error"])))))
 
+(deftest import-illegal-token
+  (let [expected (list {:file "<stdin>", :row 1, :col 9, :level :error, :message "Import target is not a package"})]
+    (assert-submaps2 expected (lint! "(import \"\")"))
+    (assert-submaps2 expected (lint! "(import 3.14)"))
+    (assert-submaps2 expected (lint! "(import -1)"))))
+
 ;;;; Scratch
 
 (comment