vcpkg: Set VCPKG_ROOT environment variable for Qt Creator process

This way CMakeProjectManager's auto-setup.cmake would pick it up and
find vcpkg.exe

Change-Id: Iafa84f13e0f50321ce771fc687ecc9e2df148de7
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/vcpkg/vcpkgplugin.cpp

@@ -5,6 +5,7 @@
 #include "vcpkg_test.h"
 #endif // WITH_TESTS
 #include "vcpkgmanifesteditor.h"
+#include "vcpkgsettings.h"
 
 #include <extensionsystem/iplugin.h>
 
@@ -35,6 +36,8 @@ public:
 #endif
     }
 
+    virtual void extensionsInitialized() final { settings().setVcpkgRootEnvironmentVariable(); }
+
     std::unique_ptr<VcpkgPluginPrivate> d;
 };
 

src/plugins/vcpkg/vcpkgsettings.cpp

@@ -42,6 +42,8 @@ VcpkgSettings::VcpkgSettings()
     if (defaultPath.isDir())
         vcpkgRoot.setDefaultValue(defaultPath.toUserOutput());
 
+    connect(this, &AspectContainer::applied, this, &VcpkgSettings::setVcpkgRootEnvironmentVariable);
+
     setLayouter([this] {
         using namespace Layouting;
         auto websiteButton = new QToolButton;
@@ -70,6 +72,12 @@ VcpkgSettings::VcpkgSettings()
     readSettings();
 }
 
+void VcpkgSettings::setVcpkgRootEnvironmentVariable()
+{
+    // Set VCPKG_ROOT environment variable so that auto-setup.cmake would pick it up
+    Environment::modifySystemEnvironment({{Constants::ENVVAR_VCPKG_ROOT, vcpkgRoot.value()}});
+}
+
 class VcpkgSettingsPage : public Core::IOptionsPage
 {
 public:

src/plugins/vcpkg/vcpkgsettings.h

@@ -12,6 +12,8 @@ class VcpkgSettings : public Utils::AspectContainer
 public:
     VcpkgSettings();
 
+    void setVcpkgRootEnvironmentVariable();
+
     Utils::FilePathAspect vcpkgRoot{this};
 };
 

src/share/3rdparty/package-manager/auto-setup.cmake

@@ -165,7 +165,7 @@ macro(qtc_auto_setup_vcpkg)
   if (EXISTS "${CMAKE_SOURCE_DIR}/vcpkg.json" AND NOT QT_CREATOR_SKIP_VCPKG_SETUP)
     option(QT_CREATOR_SKIP_VCPKG_SETUP "Skip Qt Creator's vcpkg package manager auto-setup" OFF)
 
-    find_program(vcpkg_program vcpkg ${CMAKE_SOURCE_DIR}/vcpkg)
+    find_program(vcpkg_program vcpkg $ENV{VCPKG_ROOT} ${CMAKE_SOURCE_DIR}/vcpkg)
     if (NOT vcpkg_program)
       message(WARNING "Qt Creator: vcpkg executable not found. "
                       "Package manager auto-setup will be skipped. "