🚨 Fix new warnings revealed by clang-tidy 18 (#401)

.clang-format

@@ -1,7 +1,3 @@
 BasedOnStyle: LLVM
-AlignConsecutiveAssignments: Consecutive
-AlignConsecutiveDeclarations: Consecutive
 IncludeBlocks: Regroup
-KeepEmptyLinesAtTheStartOfBlocks: false
 PointerAlignment: Left
-SpacesInContainerLiterals: false

include/Configuration.hpp

@@ -25,25 +25,25 @@ class Configuration {
   struct Execution {
     dd::fp numericalTolerance = dd::RealNumber::eps;
 
-    bool        parallel = true;
+    bool parallel = true;
     std::size_t nthreads = std::max(2U, std::thread::hardware_concurrency());
-    double      timeout  = 0.; // in seconds
+    double timeout = 0.; // in seconds
 
     bool runConstructionChecker = false;
-    bool runSimulationChecker   = true;
-    bool runAlternatingChecker  = true;
-    bool runZXChecker           = true;
+    bool runSimulationChecker = true;
+    bool runAlternatingChecker = true;
+    bool runZXChecker = true;
   };
 
   // configuration options for pre-check optimizations
   struct Optimizations {
-    bool fuseSingleQubitGates             = true;
-    bool reconstructSWAPs                 = true;
+    bool fuseSingleQubitGates = true;
+    bool reconstructSWAPs = true;
     bool removeDiagonalGatesBeforeMeasure = false;
-    bool transformDynamicCircuit          = false;
-    bool reorderOperations                = true;
-    bool backpropagateOutputPermutation   = false;
-    bool elidePermutations                = true;
+    bool transformDynamicCircuit = false;
+    bool reorderOperations = true;
+    bool backpropagateOutputPermutation = false;
+    bool elidePermutations = true;
   };
 
   // configuration options for application schemes
@@ -56,30 +56,30 @@ class Configuration {
         ApplicationSchemeType::Proportional;
 
     // options for the gate cost application scheme
-    std::string  profile;
+    std::string profile;
     CostFunction costFunction = &legacyCostFunction;
   };
 
   struct Functionality {
-    double traceThreshold          = 1e-8;
-    bool   checkPartialEquivalence = false;
+    double traceThreshold = 1e-8;
+    bool checkPartialEquivalence = false;
   };
 
   // configuration options for the simulation scheme
   struct Simulation {
-    double      fidelityThreshold = 1e-8;
-    std::size_t maxSims           = computeMaxSims();
-    StateType   stateType         = StateType::ComputationalBasis;
-    std::size_t seed              = 0U;
-    bool        storeCEXinput     = false;
-    bool        storeCEXoutput    = false;
+    double fidelityThreshold = 1e-8;
+    std::size_t maxSims = computeMaxSims();
+    StateType stateType = StateType::ComputationalBasis;
+    std::size_t seed = 0U;
+    bool storeCEXinput = false;
+    bool storeCEXoutput = false;
 
     // this function makes sure that the maximum number of simulations is
     // configured properly.
     static std::size_t computeMaxSims() {
-      constexpr std::size_t defaultMaxSims                 = 16U;
+      constexpr std::size_t defaultMaxSims = 16U;
       constexpr std::size_t defaultConfiguredOtherCheckers = 2U;
-      const auto            systemThreads = std::thread::hardware_concurrency();
+      const auto systemThreads = std::thread::hardware_concurrency();
       // catch the case where hardware_concurrency() returns 0 or the other
       // pre-configured checkers already use up all the available threads
       if (systemThreads < defaultConfiguredOtherCheckers) {
@@ -91,15 +91,15 @@ class Configuration {
   };
 
   struct Parameterized {
-    double      parameterizedTol          = 1e-12;
+    double parameterizedTol = 1e-12;
     std::size_t nAdditionalInstantiations = 0;
   };
 
-  Execution     execution{};
+  Execution execution{};
   Optimizations optimizations{};
-  Application   application{};
+  Application application{};
   Functionality functionality{};
-  Simulation    simulation{};
+  Simulation simulation{};
   Parameterized parameterized{};
 
   [[nodiscard]] bool anythingToExecute() const noexcept;

include/EquivalenceCheckingManager.hpp

@@ -9,8 +9,12 @@
 #include "EquivalenceCriterion.hpp"
 #include "QuantumComputation.hpp"
 #include "ThreadSafeQueue.hpp"
+#include "checker/EquivalenceChecker.hpp"
 #include "checker/dd/DDSimulationChecker.hpp"
+#include "checker/dd/applicationscheme/ApplicationScheme.hpp"
+#include "checker/dd/applicationscheme/GateCostApplicationScheme.hpp"
 #include "checker/dd/simulation/StateGenerator.hpp"
+#include "checker/dd/simulation/StateType.hpp"
 #include "dd/ComplexNumbers.hpp"
 #include "dd/DDDefinitions.hpp"
 
@@ -54,11 +58,11 @@ class EquivalenceCheckingManager {
 
     EquivalenceCriterion equivalence = EquivalenceCriterion::NoInformation;
 
-    std::size_t startedSimulations   = 0U;
+    std::size_t startedSimulations = 0U;
     std::size_t performedSimulations = 0U;
-    dd::CVec    cexInput;
-    dd::CVec    cexOutput1;
-    dd::CVec    cexOutput2;
+    dd::CVec cexInput;
+    dd::CVec cexOutput1;
+    dd::CVec cexOutput2;
     std::size_t performedInstantiations = 0U;
 
     nlohmann::json checkerResults = nlohmann::json::array();
@@ -85,7 +89,7 @@ class EquivalenceCheckingManager {
     }
     [[nodiscard]] std::string toString() const { return json().dump(2); }
     friend std::ostream&
-    operator<<(std::ostream&                              os,
+    operator<<(std::ostream& os,
                const EquivalenceCheckingManager::Results& res) {
       return os << res.toString();
     }
@@ -107,7 +111,7 @@ class EquivalenceCheckingManager {
     return results.equivalence;
   }
   [[nodiscard]] Configuration getConfiguration() const { return configuration; }
-  [[nodiscard]] Results       getResults() const { return results; }
+  [[nodiscard]] Results getResults() const { return results; }
 
   // convenience functions for changing the configuration after the manager has
   // been constructed: Execution: These settings may be changed to influence
@@ -138,9 +142,9 @@ class EquivalenceCheckingManager {
 
   void disableAllCheckers() {
     configuration.execution.runConstructionChecker = false;
-    configuration.execution.runZXChecker           = false;
-    configuration.execution.runSimulationChecker   = false;
-    configuration.execution.runAlternatingChecker  = false;
+    configuration.execution.runZXChecker = false;
+    configuration.execution.runSimulationChecker = false;
+    configuration.execution.runAlternatingChecker = false;
   }
 
   // Optimization: Optimizations are applied during initialization. Already
@@ -251,11 +255,11 @@ class EquivalenceCheckingManager {
   Configuration configuration{};
 
   StateGenerator stateGenerator;
-  std::mutex     stateGeneratorMutex;
+  std::mutex stateGeneratorMutex;
 
-  bool                                             done{false};
-  std::condition_variable                          doneCond;
-  std::mutex                                       doneMutex;
+  bool done{false};
+  std::condition_variable doneCond;
+  std::mutex doneMutex;
   std::vector<std::unique_ptr<EquivalenceChecker>> checkers;
 
   Results results{};
@@ -315,7 +319,7 @@ class EquivalenceCheckingManager {
   /// once it is done.
   /// \return A future that can be used to wait for the checker to finish.
   template <class Checker>
-  std::future<void> asyncRunChecker(const std::size_t             id,
+  std::future<void> asyncRunChecker(const std::size_t id,
                                     ThreadSafeQueue<std::size_t>& queue) {
     static_assert(std::is_base_of_v<EquivalenceChecker, Checker>,
                   "Checker must be derived from EquivalenceChecker");

include/EquivalenceCriterion.hpp

@@ -5,18 +5,19 @@
 
 #pragma once
 
-#include <exception>
+#include <cstdint>
 #include <iostream>
+#include <string>
 
 namespace ec {
-enum class EquivalenceCriterion {
-  NotEquivalent             = 0,
-  Equivalent                = 1,
-  NoInformation             = 2,
-  ProbablyEquivalent        = 3,
+enum class EquivalenceCriterion : std::uint8_t {
+  NotEquivalent = 0,
+  Equivalent = 1,
+  NoInformation = 2,
+  ProbablyEquivalent = 3,
   EquivalentUpToGlobalPhase = 4,
-  EquivalentUpToPhase       = 5,
-  ProbablyNotEquivalent     = 6
+  EquivalentUpToPhase = 5,
+  ProbablyNotEquivalent = 6
 };
 
 inline std::string toString(const EquivalenceCriterion& criterion) noexcept {
@@ -65,7 +66,7 @@ inline EquivalenceCriterion fromString(const std::string& criterion) noexcept {
   return EquivalenceCriterion::NoInformation;
 }
 
-inline std::istream& operator>>(std::istream&         in,
+inline std::istream& operator>>(std::istream& in,
                                 EquivalenceCriterion& criterion) {
   std::string token;
   in >> token;
@@ -79,7 +80,7 @@ inline std::istream& operator>>(std::istream&         in,
   return in;
 }
 
-inline std::ostream& operator<<(std::ostream&               out,
+inline std::ostream& operator<<(std::ostream& out,
                                 const EquivalenceCriterion& criterion) {
   out << toString(criterion);
   return out;

include/ThreadSafeQueue.hpp

@@ -38,10 +38,10 @@ template <typename T> class ThreadSafeQueue {
     auto p = std::make_unique<Node>();
     {
       const std::lock_guard tailLock(tailMutex);
-      tail->data          = data;
+      tail->data = data;
       Node* const newTail = p.get();
-      tail->next          = std::move(p);
-      tail                = newTail;
+      tail->next = std::move(p);
+      tail = newTail;
     }
     dataCond.notify_one();
   }
@@ -52,13 +52,13 @@ template <typename T> class ThreadSafeQueue {
 
 private:
   struct Node {
-    std::shared_ptr<T>    data;
+    std::shared_ptr<T> data;
     std::unique_ptr<Node> next;
   };
-  std::mutex              headMutex;
-  std::unique_ptr<Node>   head = std::make_unique<Node>();
-  std::mutex              tailMutex;
-  Node*                   tail;
+  std::mutex headMutex;
+  std::unique_ptr<Node> head = std::make_unique<Node>();
+  std::mutex tailMutex;
+  Node* tail;
   std::condition_variable dataCond;
 
   auto getTail() {
@@ -68,7 +68,7 @@ template <typename T> class ThreadSafeQueue {
 
   auto popHead() {
     auto oldHead = std::move(head);
-    head         = std::move(oldHead->next);
+    head = std::move(oldHead->next);
     return oldHead;
   }
 

include/checker/EquivalenceChecker.hpp

@@ -20,7 +20,7 @@ class EquivalenceChecker {
 public:
   EquivalenceChecker(const qc::QuantumComputation& circ1,
                      const qc::QuantumComputation& circ2,
-                     Configuration                 config) noexcept
+                     Configuration config) noexcept
       : qc1(&circ1), qc2(&circ2),
         nqubits(std::max(qc1->getNqubits(), qc2->getNqubits())),
         configuration(std::move(config)) {};
@@ -50,7 +50,7 @@ class EquivalenceChecker {
   Configuration configuration;
 
   EquivalenceCriterion equivalence = EquivalenceCriterion::NoInformation;
-  double               runtime{};
+  double runtime{};
 
 private:
   std::atomic<bool> done{false};

include/checker/dd/DDAlternatingChecker.hpp

@@ -5,19 +5,24 @@
 
 #pragma once
 
+#include "Configuration.hpp"
 #include "DDEquivalenceChecker.hpp"
 #include "DDPackageConfigs.hpp"
+#include "EquivalenceCriterion.hpp"
+#include "QuantumComputation.hpp"
 #include "applicationscheme/LookaheadApplicationScheme.hpp"
+#include "dd/Package_fwd.hpp"
 
 #include <nlohmann/json_fwd.hpp>
+#include <utility>
 
 namespace ec {
 class DDAlternatingChecker final
     : public DDEquivalenceChecker<qc::MatrixDD, AlternatingDDPackageConfig> {
 public:
   DDAlternatingChecker(const qc::QuantumComputation& circ1,
                        const qc::QuantumComputation& circ2,
-                       ec::Configuration             config)
+                       ec::Configuration config)
       : DDEquivalenceChecker(circ1, circ2, std::move(config)) {
     // gates from the second circuit shall be applied "from the right"
     taskManager2.flipDirection();
@@ -47,10 +52,10 @@ class DDAlternatingChecker final
 private:
   qc::MatrixDD functionality{};
 
-  void                 initialize() override;
-  void                 execute() override;
-  void                 finish() override;
-  void                 postprocess() override;
+  void initialize() override;
+  void execute() override;
+  void finish() override;
+  void postprocess() override;
   EquivalenceCriterion checkEquivalence() override;
 
   // at some point this routine should probably make its way into the QFR

include/checker/dd/DDConstructionChecker.hpp

@@ -23,7 +23,7 @@ class DDConstructionChecker final
 public:
   DDConstructionChecker(const qc::QuantumComputation& circ1,
                         const qc::QuantumComputation& circ2,
-                        ec::Configuration             config)
+                        ec::Configuration config)
       : DDEquivalenceChecker(circ1, circ2, std::move(config)) {
     if (this->configuration.application.constructionScheme ==
         ApplicationSchemeType::Lookahead) {

include/checker/dd/DDEquivalenceChecker.hpp

@@ -24,7 +24,7 @@ class DDEquivalenceChecker : public EquivalenceChecker {
 public:
   DDEquivalenceChecker(const qc::QuantumComputation& circ1,
                        const qc::QuantumComputation& circ2,
-                       Configuration                 config)
+                       Configuration config)
       : EquivalenceChecker(circ1, circ2, std::move(config)),
         dd(std::make_unique<dd::Package<Config>>(nqubits)),
         taskManager1(TaskManager<DDType, Config>(circ1, *dd)),