Allow --autodesktop to autoinstall desktop qt for qt6/wasm.

Apparently, Qt6 for wasm does not ship with qmake, so CI must install it.
This change leverages `--autodesktop` for that purpose.

aqt/installer.py

@@ -304,7 +304,7 @@ class Cli:
         base_path = Path(base_dir)
 
         expect_desktop_archdir, autodesk_arch = self._get_autodesktop_dir_and_arch(
-            should_autoinstall, os_name, target, base_path, _version
+            should_autoinstall, os_name, target, base_path, _version, is_wasm=(arch.startswith("wasm"))
         )
 
         auto_desktop_archives: List[QtPackage] = (
@@ -628,7 +628,7 @@ class Cli:
         install_qt_parser.add_argument(
             "--autodesktop",
             action="store_true",
-            help="For android/ios installations, a desktop Qt installation is required. "
+            help="For android, ios, and Qt6/wasm installations, a standard desktop Qt installation is required. "
             "When enabled, this option installs the required desktop version automatically.",
         )
 
@@ -970,10 +970,14 @@ class Cli:
             raise CliInputError(f"Invalid version: '{version_str}'! Please use the form '5.X.Y'.") from e
 
     def _get_autodesktop_dir_and_arch(
-        self, should_autoinstall: bool, host: str, target: str, base_path: Path, version: Version
+        self, should_autoinstall: bool, host: str, target: str, base_path: Path, version: Version, is_wasm: bool = False
     ) -> Tuple[Optional[str], Optional[str]]:
         """Returns expected_desktop_arch_dir, desktop_arch_to_install"""
-        if target in ["ios", "android"]:
+        is_wasm_qt6 = target == "desktop" and is_wasm and version >= Version("6.0.0")
+        if target not in ["ios", "android"] and not is_wasm_qt6:
+            # We do not need to worry about the desktop directory if target is not mobile, or it's not Qt6 wasm.
+            return None, None
+
         installed_desktop_arch_dir = QtRepoProperty.find_installed_desktop_qt_dir(host, base_path, version)
         if installed_desktop_arch_dir:
             # An acceptable desktop Qt is already installed, so don't do anything.
@@ -997,9 +1001,6 @@ class Cli:
                 f"          `aqt install-qt {host} desktop {version} {default_desktop_arch}`"
             )
             return expected_desktop_arch_path.name, None
-        else:
-            # We do not need to worry about the desktop directory if target is not mobile.
-            return None, None
 
 
 def is_64bit() -> bool:

ci/generate_azure_pipelines_matrices.py

@@ -270,7 +270,8 @@ windows_build_jobs.append(
     BuildJob("install-qt", "5.14.2", "windows", "desktop", "wasm_32", "wasm_32")
 )
 windows_build_jobs.append(
-    BuildJob("install-qt", "6.4.0", "windows", "desktop", "wasm_32", "wasm_32")
+    BuildJob("install-qt", "6.4.0", "windows", "desktop", "wasm_32", "wasm_32",
+             is_autodesktop=True, mingw_variant="win64_mingw900")
 )
 
 # mobile SDK

ci/steps.yml

@@ -364,7 +364,10 @@ steps:
       echo "$env:Path"
       if('$(QT_VERSION)' -like '6*') {
         echo "Qt6: run qmake.bat"
-        qmake.bat $(Build.BinariesDirectory)\tests\openglwindow
+        #qmake.bat $(Build.BinariesDirectory)\tests\openglwindow
+        # nope, just inline the bat file:
+        echo "Inlined command is: qmake -qtconf $(WIN_QT_BINDIR)\target_qt.conf $(Build.BinariesDirectory)\tests\openglwindow"
+        "$(WIN_QT_BINDIR)\..\..\mingw_64\bin\qmake.exe" -qtconf "$(WIN_QT_BINDIR)\target_qt.conf" $(Build.BinariesDirectory)\tests\openglwindow
       } else {
         echo "Qt5: run qmake.exe"
         qmake $(Build.BinariesDirectory)\tests\openglwindow