Add test for zip::urldecode().

tests/test_zip.cpp

@@ -70,3 +70,33 @@ SCENARIO("Zip file handling works")
         }
     }
 }
+
+SCENARIO("Helper functions in epubgrep::zip work")
+{
+    SECTION("urldecode() doesn't fail and returns the decoded string")
+    {
+        bool exception{false};
+
+        GIVEN("The string test%20folder/%2Afile%5Btest%5D%2A")
+        {
+            std::string encoded_text{"test%20folder/%2Afile%5Btest%5D%2A"};
+            std::string decoded_text{};
+
+            try
+            {
+                decoded_text = epubgrep::zip::urldecode(encoded_text);
+            }
+            catch (const std::exception &)
+            {
+                exception = true;
+            }
+
+            THEN("No exception is thrown")
+            AND_THEN("It returns the TOC correctly")
+            {
+                REQUIRE_FALSE(exception);
+                REQUIRE(decoded_text == "test folder/*file[test]*");
+            }
+        }
+    }
+}