SONARJAVA-5149 report issues with path delimiters in variable declaration (#4962)

Author: erwan-serandour

java-checks-test-sources/default/src/main/java/checks/HardcodedURICheckSample.java

@@ -35,6 +35,7 @@ void foo(String s, String var) throws URISyntaxException {
     new File("", s); // Compliant
     new File("", s + "/" + s); // Noncompliant {{Remove this hard-coded path-delimiter.}}
 //                   ^^^
+    String path1 = "a" + "/" + "b"; // Noncompliant {{Remove this hard-coded path-delimiter.}}
 
     new URI("http:https"); // Compliant
     new URI("http://www.mywebsite.com"); // Noncompliant {{Refactor your code to get this URI from a customizable parameter.}}

java-checks/src/main/java/org/sonar/java/checks/HardcodedURICheck.java

@@ -179,6 +179,8 @@ private void checkVariable(VariableTree tree) {
 
     String stringLiteral = stringLiteral(initializer);
     if (stringLiteral == null) {
+      // The check below applies only to binary expressions, so we apply it only if the initializer is not a literal.
+      reportStringConcatenationWithPathDelimiter(initializer);
       return;
     }