CLJS-3133: simple-* / qualified-* predicate-induced inference

Author: mfikes

src/main/clojure/cljs/analyzer.cljc

@@ -1550,6 +1550,12 @@
     cljs.core/delay?          cljs.core/Delay
     cljs.core/reduced?        cljs.core/Reduced
 
+    ;; Subtypes
+    cljs.core/simple-keyword?    cljs.core/Keyword
+    cljs.core/qualified-keyword? cljs.core/Keyword
+    cljs.core/simple-symbol?     cljs.core/Symbol
+    cljs.core/qualified-symbol?  cljs.core/Symbol
+
     ;;; Note: For non-marker protocol entries below, we
     ;;; omit predicates that are based on satisfies? because
     ;;; we cannot safely apply the fast-path optimization
@@ -1570,6 +1576,10 @@
     ;; Composites
     cljs.core/seqable?        #{cljs.core/ISeqable array string}
     cljs.core/ident?          #{cljs.core/Keyword cljs.core/Symbol}
+
+    ;; Composite subtypes
+    cljs.core/simple-ident?    #{cljs.core/Keyword cljs.core/Symbol}
+    cljs.core/qualified-ident? #{cljs.core/Keyword cljs.core/Symbol}
     })
 
 (defn- simple-predicate-induced-tag

src/test/clojure/cljs/analyzer_tests.clj

@@ -2054,3 +2054,40 @@
     (is #(= '#{([this] [this x] [this x y])} (set (map :arglists (vals sigs)))))
     (is #(= '#{"foo fn" "bar fn" "baz fn"} (set (map :doc (vals sigs)))))))
 
+(deftest test-cljs-3133
+  (is (= (ana/no-warn
+           (env/with-compiler-env test-cenv
+             (:tag (ana/analyze test-env '(let [x ^any []] (if (keyword? x) x nil))))))
+        '#{cljs.core/Keyword clj-nil}))
+  (is (= (ana/no-warn
+           (env/with-compiler-env test-cenv
+             (:tag (ana/analyze test-env '(let [x ^any []] (if (simple-keyword? x) x nil))))))
+        '#{cljs.core/Keyword clj-nil}))
+  (is (= (ana/no-warn
+           (env/with-compiler-env test-cenv
+             (:tag (ana/analyze test-env '(let [x ^any []] (if (qualified-keyword? x) x nil))))))
+        '#{cljs.core/Keyword clj-nil}))
+  (is (= (ana/no-warn
+           (env/with-compiler-env test-cenv
+             (:tag (ana/analyze test-env '(let [x ^any []] (if (symbol? x) x nil))))))
+        '#{cljs.core/Symbol clj-nil}))
+  (is (= (ana/no-warn
+           (env/with-compiler-env test-cenv
+             (:tag (ana/analyze test-env '(let [x ^any []] (if (simple-symbol? x) x nil))))))
+        '#{cljs.core/Symbol clj-nil}))
+  (is (= (ana/no-warn
+           (env/with-compiler-env test-cenv
+             (:tag (ana/analyze test-env '(let [x ^any []] (if (qualified-symbol? x) x nil))))))
+        '#{cljs.core/Symbol clj-nil}))
+  (is (= (ana/no-warn
+           (env/with-compiler-env test-cenv
+             (:tag (ana/analyze test-env '(let [x ^any []] (if (ident? x) x nil))))))
+        '#{cljs.core/Keyword cljs.core/Symbol clj-nil}))
+  (is (= (ana/no-warn
+           (env/with-compiler-env test-cenv
+             (:tag (ana/analyze test-env '(let [x ^any []] (if (simple-ident? x) x nil))))))
+        '#{cljs.core/Keyword cljs.core/Symbol clj-nil}))
+  (is (= (ana/no-warn
+           (env/with-compiler-env test-cenv
+             (:tag (ana/analyze test-env '(let [x ^any []] (if (qualified-ident? x) x nil))))))
+        '#{cljs.core/Keyword cljs.core/Symbol clj-nil})))