Add test where tmp_if_expr is introduced

This checks the ID_mode fix for if_expr in preprocessing works correctly.

Author: romainbrenguier

regression/jbmc-strings/char_escape/Test.class

@@ -0,0 +1,19 @@
+public class Test {
+
+    public static boolean test(char c1, char c2, char c3, char c4, char c5, char c6, char c7, char c8) {
+        StringBuilder sb = new StringBuilder("");
+        sb.append(c1);
+        sb.append(c2);
+        sb.append(c3);
+        sb.append(c4);
+        sb.append(c5);
+        sb.append(c6);
+        sb.append(c7);
+        sb.append(c8);
+        if (sb.toString().equals("\b\t\n\f\r\"\'\\"))
+            return true;
+        if (!sb.toString().equals("\b\t\n\f\r\"\'\\"))
+            return false;
+        return true;
+    }
+}

regression/jbmc-strings/char_escape/Test.java

@@ -0,0 +1,6 @@
+CORE
+Test.class
+--refine-strings --function Test.test --cover location --trace --json-ui
+^EXIT=0$
+^SIGNAL=0$
+20 of 23 covered \(87.0%\)|30 of 44 covered \(68.2%\)