Fix UnsupportedOperationException in AbstractRegexCheckTrackingMatche…

…rs.onMethodInvocationFound (#3331)
SonarSource · Dec 7, 2020 · 5b61d27 · 5b61d27
1 parent 805686d
commit 5b61d27
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Showing 2 changed files with 9 additions and 3 deletions.
diff --git a/java-checks-test-sources/src/main/java/checks/regex/RegexLookaheadCheck.java b/java-checks-test-sources/src/main/java/checks/regex/RegexLookaheadCheck.java
@@ -20,6 +20,12 @@ public void test() {
     f(compile("(?=a)ab").matcher("abc").find());
     f(compile("(?=abc)ab").matcher("abc").matches()); // Noncompliant
     f(compile("(?=abc)ab").matcher("abc").find());
+
+    // string regex and pattern regex share the same string literal
+    String pattern_str = "(?=a)b"; // Noncompliant
+    Pattern pattern = Pattern.compile(pattern_str);
+    f("".matches(pattern_str));
+    f(pattern.matcher("").matches());
   }
 
   abstract void f(Pattern pattern);

diff --git a/...-checks/src/main/java/org/sonar/java/checks/regex/AbstractRegexCheckTrackingMatchers.java b/...-checks/src/main/java/org/sonar/java/checks/regex/AbstractRegexCheckTrackingMatchers.java
@@ -206,7 +206,7 @@ private Optional<RegexParseResult> getRegexOperand(MethodInvocationTree mit) {
   @Override
   public void checkRegex(RegexParseResult regexForLiterals, ExpressionTree methodInvocationOrAnnotation) {
     if (methodInvocationOrAnnotation.is(Tree.Kind.ANNOTATION)) {
-      methodsCalledOnRegex.put(regexForLiterals, Collections.emptyList());
+      methodsCalledOnRegex.put(regexForLiterals, new ArrayList<>());
       return;
     }
     MethodInvocationTree mit = (MethodInvocationTree) methodInvocationOrAnnotation;
@@ -215,9 +215,9 @@ public void checkRegex(RegexParseResult regexForLiterals, ExpressionTree methodI
       methodInvocationToRegex.put(mit, regexForLiterals);
       methodsCalledOnRegex.put(regexForLiterals, new ArrayList<>());
     } else if (trackedMethodMatchers().matches(mit)) {
-      methodsCalledOnRegex.put(regexForLiterals, Collections.singletonList(mit));
+      methodsCalledOnRegex.put(regexForLiterals, new ArrayList<>(Collections.singletonList(mit)));
     } else {
-      methodsCalledOnRegex.put(regexForLiterals, Collections.emptyList());
+      methodsCalledOnRegex.put(regexForLiterals, new ArrayList<>());
     }
   }