Minor suggestions from clangtidy

include/valijson/adapters/adapter.hpp

@@ -35,7 +35,7 @@ public:
      * @brief   Virtual destructor defined to ensure deletion via base-class
      *          pointers is safe.
      */
-    virtual ~Adapter() { };
+    virtual ~Adapter() = default;;
 
     /**
      * @brief   Apply a callback function to each value in an array.

include/valijson/constraint_builder.hpp

@@ -13,7 +13,7 @@ namespace constraints {
 class ConstraintBuilder
 {
 public:
-    virtual ~ConstraintBuilder() {}
+    virtual ~ConstraintBuilder() = default;
 
     virtual constraints::Constraint * make(const adapters::Adapter &) const = 0;
 };

include/valijson/constraints/concrete_constraints.hpp

@@ -365,6 +365,7 @@ public:
                     m_enumValues.push_back(value);
                 } catch (...) {
                     delete value;
+                    value = nullptr;
                     throw;
                 }
             }

include/valijson/constraints/constraint.hpp

@@ -21,7 +21,7 @@ struct Constraint
     /**
      * @brief  Virtual destructor.
      */
-    virtual ~Constraint() { }
+    virtual ~Constraint() = default;
 
     /**
      * @brief  Perform an action on the constraint using the visitor pattern.

include/valijson/constraints/constraint_visitor.hpp

@@ -36,7 +36,7 @@ class UniqueItemsConstraint;
 class ConstraintVisitor
 {
 protected:
-    virtual ~ConstraintVisitor() {}
+    virtual ~ConstraintVisitor() = default;
 
     // Shorten type names for derived classes outside of this namespace
     typedef constraints::AllOfConstraint AllOfConstraint;

include/valijson/internal/json_pointer.hpp

@@ -50,7 +50,7 @@ inline char decodePercentEncodedChar(const std::string &digits)
 
     errno = 0;
     const char *begin = digits.c_str();
-    char *end = NULL;
+    char *end = nullptr;
     const unsigned long value = strtoul(begin, &end, 16);
     if (end != begin && *end != '\0') {
         throw std::runtime_error("Failed to decode %-encoded character '" +
@@ -178,7 +178,7 @@ inline AdapterType resolveJsonPointer(
         return resolveJsonPointer(node, jsonPointer, jsonPointerNext);
 
     } else if (node.isArray()) {
-        if (referenceToken.compare("-") == 0) {
+        if (referenceToken == "-") {
             throw std::runtime_error("Hyphens cannot be used as array indices "
                     "since the requested array element does not yet exist");
         }

include/valijson/internal/json_reference.hpp

@@ -20,7 +20,7 @@ namespace json_reference {
 inline opt::optional<std::string> getJsonReferenceUri(
     const std::string &jsonRef)
 {
-    const size_t ptrPos = jsonRef.find("#");
+    const size_t ptrPos = jsonRef.find('#');
     if (ptrPos == 0) {
         // The JSON Reference does not contain a URI, but might contain a
         // JSON Pointer that refers to the current document
@@ -47,7 +47,7 @@ inline opt::optional<std::string> getJsonReferencePointer(
     // Attempt to extract JSON Pointer if '#' character is present. Note
     // that a valid pointer would contain at least a leading forward
     // slash character.
-    const size_t ptrPos = jsonRef.find("#");
+    const size_t ptrPos = jsonRef.find('#');
     if (ptrPos != std::string::npos) {
         return jsonRef.substr(ptrPos + 1);
     }