CLJ-2585 - Fix index check in nth with not-found for regex matcher

puredanger · stuarthalloway · commit e0ac2d705e6b · 2020-12-11T13:43:50.000-05:00
Signed-off-by: Stuart Halloway &lt;stu@cognitect.com&gt;
diff --git a/src/jvm/clojure/lang/RT.java b/src/jvm/clojure/lang/RT.java
@@ -965,7 +965,8 @@ else if(coll instanceof RandomAccess) {
 	}
 	else if(coll instanceof Matcher) {
 		Matcher m = (Matcher) coll;
-		if(n < m.groupCount())
+		int groups = m.groupCount();
+		if(groups > 0 && n <= m.groupCount())
 			return m.group(n);
 		return notFound;
 	}
diff --git a/test/clojure/test_clojure/other_functions.clj b/test/clojure/test_clojure/other_functions.clj
@@ -348,6 +348,19 @@
 ; Regex Support
 ; re-matcher re-find re-matches re-groups re-seq
 
+(deftest test-regex-matcher
+  (let [matcher (re-matcher #"(\d{2})/(\d{2})/(\d{4})" "12/02/1975")]
+    (is (= ["12/02/1975" "12" "02" "1975"] (re-find matcher)))
+    (is (= ["12/02/1975" "12" "02" "1975"] (re-groups matcher)))
+    (is (= "12/02/1975" (nth matcher 0) (nth matcher 0 :foo)))
+    (is (= "12" (nth matcher 1) (nth matcher 1 :foo)))
+    (is (= "02" (nth matcher 2) (nth matcher 2 :foo)))
+    (is (= "1975" (nth matcher 3) (nth matcher 3 :foo)))
+    (is (thrown? IndexOutOfBoundsException (nth matcher -1)))
+    (is (= :foo (nth matcher -1 :foo)))
+    (is (thrown? IndexOutOfBoundsException (nth matcher 4)))
+    (is (= :foo (nth matcher 4 :foo)))))
+
 ; update
 
 (deftest test-update

Original file line number	Diff line number	Diff line change
`@@ -965,7 +965,8 @@ else if(coll instanceof RandomAccess) {`
`965`	`965`	`}`
`966`	`966`	`else if(coll instanceof Matcher) {`
`967`	`967`	`Matcher m = (Matcher) coll;`
`968`		`- if(n < m.groupCount())`
	`968`	`+ int groups = m.groupCount();`
	`969`	`+ if(groups > 0 && n <= m.groupCount())`
`969`	`970`	`return m.group(n);`
`970`	`971`	`return notFound;`
`971`	`972`	`}`