From 3a03f075606b19e411b8bd19870242e0e0b58fcb Mon Sep 17 00:00:00 2001
From: Anthony Towns <aj@erisian.com.au>
Date: Tue, 29 Jul 2025 09:12:46 +0100
Subject: [PATCH] qt: Avoid header circular dependency

---
 src/qt/freespacechecker.cpp             |  6 ------
 src/qt/freespacechecker.h               | 12 ++++++++----
 src/qt/intro.h                          |  8 ++++----
 test/lint/lint-circular-dependencies.py |  1 -
 4 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/src/qt/freespacechecker.cpp b/src/qt/freespacechecker.cpp
index e0f6fff3183..53cb6a71510 100644
--- a/src/qt/freespacechecker.cpp
+++ b/src/qt/freespacechecker.cpp
@@ -5,7 +5,6 @@
 #include <qt/freespacechecker.h>
 
 #include <qt/guiutil.h>
-#include <qt/intro.h>
 #include <util/fs.h>
 
 #include <QDir>
@@ -13,11 +12,6 @@
 
 #include <cstdint>
 
-FreespaceChecker::FreespaceChecker(Intro *_intro)
-{
-    this->intro = _intro;
-}
-
 void FreespaceChecker::check()
 {
     QString dataDirStr = intro->getPathToCheck();
diff --git a/src/qt/freespacechecker.h b/src/qt/freespacechecker.h
index ebd36bde974..e1746a8f457 100644
--- a/src/qt/freespacechecker.h
+++ b/src/qt/freespacechecker.h
@@ -9,8 +9,6 @@
 #include <QString>
 #include <QtGlobal>
 
-class Intro;
-
 /* Check free space asynchronously to prevent hanging the UI thread.
 
    Up to one request to check a path is in flight to this thread; when the check()
@@ -26,7 +24,13 @@ class FreespaceChecker : public QObject
     Q_OBJECT
 
 public:
-    explicit FreespaceChecker(Intro *intro);
+    class PathQuery
+    {
+    public:
+        virtual QString getPathToCheck() = 0;
+    };
+
+    explicit FreespaceChecker(PathQuery* intro) : intro{intro} {}
 
     enum Status {
         ST_OK,
@@ -40,7 +44,7 @@ Q_SIGNALS:
     void reply(int status, const QString &message, quint64 available);
 
 private:
-    Intro *intro;
+    PathQuery* intro;
 };
 
 #endif // BITCOIN_QT_FREESPACECHECKER_H
diff --git a/src/qt/intro.h b/src/qt/intro.h
index 1fac5c39531..db6c1d50b23 100644
--- a/src/qt/intro.h
+++ b/src/qt/intro.h
@@ -5,14 +5,14 @@
 #ifndef BITCOIN_QT_INTRO_H
 #define BITCOIN_QT_INTRO_H
 
+#include <qt/freespacechecker.h>
+
 #include <QDialog>
 #include <QMutex>
 #include <QThread>
 
 static const bool DEFAULT_CHOOSE_DATADIR = false;
 
-class FreespaceChecker;
-
 namespace interfaces {
     class Node;
 }
@@ -25,7 +25,7 @@ namespace Ui {
   Allows the user to choose a data directory,
   in which the wallet and block chain will be stored.
  */
-class Intro : public QDialog
+class Intro : public QDialog, public FreespaceChecker::PathQuery
 {
     Q_OBJECT
 
@@ -78,7 +78,7 @@ private:
 
     void startThread();
     void checkPath(const QString &dataDir);
-    QString getPathToCheck();
+    QString getPathToCheck() override;
     void UpdatePruneLabels(bool prune_checked);
     void UpdateFreeSpaceLabel();
 
diff --git a/test/lint/lint-circular-dependencies.py b/test/lint/lint-circular-dependencies.py
index 2ec79724d10..9554e560650 100755
--- a/test/lint/lint-circular-dependencies.py
+++ b/test/lint/lint-circular-dependencies.py
@@ -16,7 +16,6 @@ EXPECTED_CIRCULAR_DEPENDENCIES = (
     "node/blockstorage -> validation -> node/blockstorage",
     "node/utxo_snapshot -> validation -> node/utxo_snapshot",
     "qt/addresstablemodel -> qt/walletmodel -> qt/addresstablemodel",
-    "qt/freespacechecker -> qt/intro -> qt/freespacechecker",
     "qt/recentrequeststablemodel -> qt/walletmodel -> qt/recentrequeststablemodel",
     "qt/sendcoinsdialog -> qt/walletmodel -> qt/sendcoinsdialog",
     "qt/transactiontablemodel -> qt/walletmodel -> qt/transactiontablemodel",