subagent transcript

session 17f09f89 · workflow wf_4e894f41
← 17f09f89 · archive
delegated task
You are working on the FreeCAD -> WebAssembly port. Ground EVERYTHING in the real code; do not guess. - Source tree: /home/magik6k/lcad-wasm/freecad-p
▸ Magik
You are working on the FreeCAD -> WebAssembly port. Ground EVERYTHING in the real code; do not guess. - Source tree: /home/magik6k/lcad-wasm/freecad-port/FreeCAD (git branch wasm-port). CMake build dir (out-of-source, already configured): /opt/toolchains/src/freecad-gui-build — read /opt/toolchains/src/freecad-gui-build/CMakeCache.txt for BUILD_* flags and dep paths. Build binary: bin/FreeCAD.wasm (~180 MB). - Toolchain: emscripten, ASYNCIFY + JS exceptions (-fexceptions), SINGLE-THREADED (no pthreads). Static CPython 3.14 + static Qt 6.11 (wasm) + static OCCT + static Coin3D. Everything is statically linked; there is NO dlopen — Python C-extension modules are registered statically via PyImport_AppendInittab in the generated file src/Main/WasmInittab.cpp / WasmInittabGui.cpp (see also freecadWasmRegisterInittab in src/Main/MainGui.cpp). - CRITICAL wasm constraints you MUST check for and design around: (1) THREADING HANGS: any std::thread ctor / std::async(default or async policy) / QThreadPool / QtConcurrent / QThread worker HANGS or throws (no pthreads). Fix pattern: force synchronous/deferred on __EMSCRIPTEN__ (e.g. std::launch::deferred), or #ifndef FC_OS_WASM guard the worker and run inline. Example already in-tree: Mod/Sketcher/App/planegcs/GCS.cpp forced std::launch::deferred; App/Application.cpp guards _recomputeThread with #ifndef FC_OS_WASM; Gui/ProgressBar.cpp skips qApp->processEvents() on __EMSCRIPTEN__. (2) MODAL DIALOGS / NESTED EVENT LOOPS: QDialog::exec()/QMessageBox::exec()/QEventLoop::exec() may deadlock under asyncify when driven from outside the main loop. Task-panel (docked, non-modal) dialogs are preferred. (3) Reentrant ccalls from JS during asyncify suspend corrupt state — a QTimer command-pump (/fc-cmd.py) exists for JS->Python. QtWebEngine has NO wasm port (Web workbench / in-app help / real Start page can't use it). (4) Wasm guards used in-tree: __EMSCRIPTEN__ (compiler-provided) and FC_OS_WASM (FreeCAD-defined) — both are defined on wasm. - Built modules today: Part, Sketcher, Material, Start (+ kernel). Everything else is OFF (see BUILD_* in CMakeCache). - PySide/shiboken: FREECAD_USE_PYSIDE=OFF, FREECAD_USE_SHIBOKEN=OFF, PySide6_DIR/Shiboken6_DIR NOTFOUND. Python 'PySide'/'shiboken6' import fails at runtime ("Cannot load shiboken6"). Many workbenches (Draft, BIM, most task dialogs) are Python+PySide and cannot function without it. DELIVERABLES — do BOTH: 1) Write a thorough, concrete, ready-to-apply plan to /home/magik6k/lcad-wasm/porting/<SLUG>/plan.md — include: exact CMake flags/edits, exact source edits (file + before/after or unified-diff snippets precise enough to apply), any NEW files (full contents), external-dependency build recipes (how to build each dep for this emscripten/asyncify toolchain), a threading-hazard list (grep the real files, give file:line + the exact construct + the exact fix), a modal-dialog-hazard list, the PyImport_AppendInittab lines to add, an ordered step list, and an effort/risk estimate. Put any patch files or new-file contents as separate files in that dir too. 2) Return the structured summary (the schema). Keep summary fields concise; the depth goes in plan.md. Your returned text IS the structured object. Be exhaustive and correct — token cost is not a concern. Verify claims against the actual files (use grep/read). If a dependency has no known wasm port, say so plainly and estimate the porting effort. === YOUR SCOPE: QtWebEngine-dependent surfaces (slug: webengine-stub) === QtWebEngine has no wasm port. Find every use in src/ (grep QtWebEngine, QWebEngineView, WebGui, Mod/Web, the Start page HTML view, in-app Help/DlgReport help browser). For each, propose the wasm approach: stub, replace with a plain widget, or route to an external link. Assess how the Start workbench currently renders (it IS built — how does it avoid WebEngine?). Write your full plan + any patch/new-file contents under /home/magik6k/lcad-wasm/porting/webengine-stub/ (create the dir; plan.md is required). Then return the structured summary with deliverableFile=/home/magik6k/lcad-wasm/porting/webengine-stub/plan.md.
Fable
thinking
I'm going to search through the codebase to see how QtWebEngine is being used.
Fable
I'll investigate the QtWebEngine usage across the FreeCAD source tree, grounding everything in the actual code.
Fable
⚙ Bash {"command": "git branch 2>/dev/null | head; echo \"---GREP QtWebEngine---\"; grep -rl \"QtWebEngine\\|QWebEngine\\|QWebView\\|QtWebKit\" src/ --include=*.cpp --include=*.h --include=*.txt --include=*.cmake --include=*.py 2>/dev/null | head …
tool result
  main
* wasm-port
---GREP QtWebEngine---
src/Mod/Help/Help.py
Fable
⚙ Bash {"command": "echo \"=== Mod/Web dir ===\"; ls src/Mod/Web 2>/dev/null; echo \"=== Mod/Start dir ===\"; ls src/Mod/Start 2>/dev/null; echo \"=== WebGui ===\"; ls src/Mod/Web/Gui 2>/dev/null", "description": "List Web and Start module dirs"}
tool result
Exit code 2
=== Mod/Web dir ===
App
CMakeLists.txt
Init.py
WebGlobal.h
web.dox
=== Mod/Start dir ===
App
CMakeLists.txt
Gui
Init.py
InitGui.py
README.md
StartGlobal.h
StartMigrator.py
=== WebGui ===
Fable
thinking
The grep only caught Help.py, so I need to search more broadly for different QtWebEngine imports like webenginewidgets or QWebEngineView to find all the places it's being used.
Fable
⚙ Bash {"command": "cd src; grep -rli \"webengine\\|webview\\|webkit\\|qwebengine\\|WebEngineWidgets\" . 2>/dev/null | head -100", "description": "Broad case-insensitive webengine search"}
tool result
3rdParty/FastSignals/.clang-format
3rdParty/coin/docs/doxygen-awesome/logo.drawio.svg
3rdParty/coin/docs/doxygen-awesome/Doxyfile
3rdParty/coin/docs/doxygen-awesome/doxygen-awesome.css
3rdParty/coin/docs/doxygen/stylesheet.css
Doc/templates/customdoxygen.css
Doc/BuildWebDoc.cfg.in
Mod/BIM/Resources/templates/webgl_export_template.html
Mod/CAM/Path/Main/Sanity/HTMLTemplate.py
Mod/Help/Resources/translations/Help_be.ts
Mod/Help/Resources/translations/Help_de.ts
Mod/Help/Resources/translations/Help  …[truncated]
Fable
⚙ Bash {"command": "cd src; grep -rli \"webengine\\|webkit\" --include=CMakeLists.txt . 2>/dev/null; echo \"=== find Web modules ===\"; find . -type d -iname \"*web*\" 2>/dev/null", "description": "Find web CMake and dirs"}
tool result
=== find Web modules ===
./Mod/Web
Fable
thinking
I notice there's no WebGui module in this codebase—just Mod/Web with an App component. Let me trace through the key web-related surfaces: the Web module itself, the Help.py file that uses QtWebEngine, how the Start module renders since it's built, the in-app help and report dialogs, and the general web/report browser functionality in Gui. I'll also search for QTextBrowser and related help browser components to understand the full picture.
Fable
⚙ Bash {"command": "cd src; echo \"=== Mod/Web/CMakeLists ===\"; cat Mod/Web/CMakeLists.txt; echo; echo \"=== Mod/Web/App files ===\"; ls Mod/Web/App", "description": "Inspect Mod/Web"}
tool result
=== Mod/Web/CMakeLists ===
# SPDX-License-Identifier: LGPL-2.1-or-later

add_subdirectory(App)

set(Web_Scripts
    Init.py
)

add_custom_target(WebScripts ALL
    SOURCES ${Web_Scripts}
)

fc_target_copy_resource_flat(WebScripts
    ${CMAKE_CURRENT_SOURCE_DIR}
    ${CMAKE_BINARY_DIR}/Mod/Web
    ${Web_Scripts}
)

INSTALL(
    FILES
        ${Web_Scripts}
    DESTINATION
        Mod/Web
)

=== Mod/Web/App files ===
AppWeb.cpp
CMakeLists.txt
PreCompiled.h
Server.cpp
Server.h
Fable
⚙ Bash {"command": "cd src; echo \"=== Mod/Start/Gui ===\"; ls -la Mod/Start/Gui; echo \"=== Start CMakeLists ===\"; cat Mod/Start/Gui/CMakeLists.txt 2>/dev/null | head -80", "description": "Inspect Start Gui"}
tool result
=== Mod/Start/Gui ===
total 164
drwxr-xr-x 1 agent agent   862 Jul  3 17:58 .
drwxr-xr-x 1 agent agent   150 Jul  3 17:58 ..
-rw-r--r-- 1 agent agent  4867 Jul  3 17:58 AppStartGui.cpp
-rw-r--r-- 1 agent agent  4688 Jul  3 17:58 CMakeLists.txt
-rw-r--r-- 1 agent agent  5296 Jul  3 17:58 DlgStartPreferences.ui
-rw-r--r-- 1 agent agent  3054 Jul  3 17:58 DlgStartPreferencesImp.cpp
-rw-r--r-- 1 agent agent  2234 Jul  3 17:58 DlgStartPreferencesImp.h
-rw-r--r-- 1 agent agent  9939 Jul  3 17:58 FileC  …[truncated]
Fable
thinking
So StartView.cpp is a native Qt Widgets implementation without WebEngine, using FileCardView and FlowLayout instead of the old WebView-based approach. Now I'm looking at where WebEngine actually surfaces in FreeCAD — the Web workbench seems to be the main candidate, though I need to verify whether Server.cpp uses WebEngine or something else.

Help.py appears to be the primary WebEngine consumer for in-app documentation. Let me check what the Gui help mechanisms use — whether it's QTextBrowser, an Assistant dialog, or something else — and also verify if the Web module has any GUI components in this tree or if they were removed.
Fable
⚙ Bash {"command": "cd src; echo \"=== Help.py webengine refs ===\"; grep -n \"WebEngine\\|QWebEngine\\|webengine\\|QtWebEngineWidgets\\|QTextBrowser\\|import\" Mod/Help/Help.py | head -60", "description": "Help.py webengine usage"}
tool result
=== Help.py webengine refs ===
36:    import Help
56:import os
57:import re
58:import urllib.request
59:import urllib.error
60:import FreeCAD
80:    "PySide QtWebEngineWidgets module is not available. Help rendering is done with the system browser",
249:    from PySide import QtCore, QtGui
255:            import webbrowser
259:        import webbrowser
267:    from PySide import QtCore
279:    from PySide import QtCore
289:    """verifies if qtwebengine is available"""
292:        from PySide im  …[truncated]
Fable
⚙ Bash {"command": "cd src; echo \"=== git log Web Gui removed? ===\"; git log --oneline -5 -- Mod/Web 2>/dev/null; echo \"=== search WebGui refs anywhere ===\"; grep -rn \"WebGui\\|Web/Gui\\|BrowserView\\|WebView\" --include=*.cpp --include=*.h -…
tool result
=== git log Web Gui removed? ===
ca9e1ecdf3 All: Header Guards ➞ Pragma Once (#27154)
2db8942fa9 Web: improve docs by explaining purpose and use
25c3ba7338 All: Reformat according to new standard
00887c4f3a [ Web ]: Update SPDX License Identifiers
c3805ecf4a fix duplicate include guards in precompiled headers
=== search WebGui refs anywhere ===
Mod/BIM/bimcommands/BimSetup.py:87:        # disabled as WebTools can currentyl not be installed because of WebGui dependency
Mod/Web/WebGlobal.h:39:// W  …[truncated]
Fable
thinking
I'm checking whether the Web module actually requires WebEngine, since the browser view was removed upstream in favor of the Help module. I need to examine the Help.py file, the Web Server implementation, and the CMake build configuration to understand what's actually being built.
Fable
⚙ Bash {"command": "grep -iE \"BUILD_WEB|BUILD_HELP|BUILD_START|BUILD_ADDONMGR|FREECAD_USE_PYSIDE|FREECAD_USE_QTWEBENGINE|QtWebEngine|WITH_QTWEBENGINE\" /opt/toolchains/src/freecad-gui-build/CMakeCache.txt 2>/dev/null", "description": "Check build…
tool result
BUILD_ADDONMGR:BOOL=OFF
BUILD_HELP:BOOL=OFF
BUILD_START:BOOL=ON
BUILD_WEB:BOOL=OFF
FREECAD_USE_PYSIDE:BOOL=OFF
Fable
⚙ Bash {"command": "cd src; echo \"=== AppWeb.cpp head ===\"; sed -n '1,60p' Mod/Web/App/AppWeb.cpp; echo \"=== Server.h ===\"; grep -n \"include\\|class\\|QWeb\\|QTcp\\|Web\" Mod/Web/App/Server.h | head -40", "description": "Inspect Web App serve…
tool result
=== AppWeb.cpp head ===
// SPDX-License-Identifier: LGPL-2.1-or-later

/***************************************************************************
 *   Copyright (c) 2014 Werner Mayer <wmayer[at]users.sourceforge.net>     *
 *                                                                         *
 *   This file is part of the FreeCAD CAx development system.              *
 *                                                                         *
 *   This library is free software; you can   …[truncated]
Fable
thinking
I'm mapping out the build configuration: Web, Help, and AddOn Manager are all disabled, while the Start module is enabled. The Web app uses QTcpServer without WebEngine, which wouldn't work on WebAssembly anyway since it's off. The Help module is the only one using QtWebEngine, but it's also disabled and requires PySide.

Now I need to verify the Gui module doesn't depend on WebEngine, and check for any other help or browser surfaces—like Qt Assistant, online help viewers, or the report dialog. I should also look at whether there's a WebEngine-based Start page alternative and confirm what the report view actually uses.
Fable
⚙ Bash {"command": "cd src; echo \"=== whole-tree webengine (excl translations/3rdParty/docs) ===\"; grep -rniE \"qwebengine|webenginewidgets|qtwebengine|QWebView|QtWebKit\" . --include=*.cpp --include=*.h --include=*.py --include=*.ui --include=C…
tool result
=== whole-tree webengine (excl translations/3rdParty/docs) ===
Mod/Help/dlgPreferencesHelp.ui:199:         <string>The documentation will open in a new tab inside the FreeCAD interface. This requires the PySide QtWebengineWidgets component.</string>
Mod/Help/dlgPreferencesHelp.ui:222:Requires the PySide QtWebengineWidgets component.</string>
Mod/Help/Help.py:80:    "PySide QtWebEngineWidgets module is not available. Help rendering is done with the system browser",
Mod/Help/Help.py:289:    """ver  …[truncated]
Fable
⚙ Bash {"command": "cd src; echo \"=== Gui help/online browser refs ===\"; grep -rniE \"OnlineHelp|QTextBrowser|showDocumentation|Assistant|help.setUrl|QDesktopServices|openUrl\" Gui/*.cpp Gui/*.h 2>/dev/null | head -40", "description": "Gui help …
tool result
=== Gui help/online browser refs ===
Gui/Assistant.cpp:33:#include "Assistant.h"
Gui/Assistant.cpp:37:/* TRANSLATOR Gui::Assistant */
Gui/Assistant.cpp:39:Assistant::Assistant()
Gui/Assistant.cpp:43:Assistant::~Assistant()
Gui/Assistant.cpp:51:void Assistant::showDocumentation(const QString& page)
Gui/Assistant.cpp:53:    if (!startAssistant()) {
Gui/Assistant.cpp:63:bool Assistant::startAssistant()
Gui/Assistant.cpp:67:        connect(proc, &QProcess::readyReadStandardOutput, this, &Assi  …[truncated]
Fable
thinking
I'm seeing how the C++ GUI handles documentation through two main paths: Qt Assistant for local help via QProcess, which won't work in WebAssembly, and QDesktopServices for opening URLs in the browser. Let me trace through the MainWindow and OpenURLInBrowser implementations to understand the routing logic.
Fable
⚙ Bash {"command": "cd src; echo \"=== MainWindow::showDocumentation ===\"; grep -n \"showDocumentation\\|OpenURLInBrowser\\|QDesktopServices\\|assistant\\|Assistant\" Gui/MainWindow.cpp | head; echo \"=== OpenURLInBrowser def ===\"; grep -rn \"Op…
tool result
=== MainWindow::showDocumentation ===
31:#include <QDesktopServices>
93:#include "Assistant.h"
343:    Assistant* assistant;
366:    d->assistant = new Assistant();
1184:void MainWindow::showDocumentation(const QString& help)
1239:        showDocumentation(wt->href());
1790:        delete d->assistant;
1791:        d->assistant = nullptr;
=== OpenURLInBrowser def ===
Gui/CommandStd.cpp:586:    OpenURLInBrowser(url.c_str());
Gui/CommandStd.cpp:615:    OpenURLInBrowser(url.c_str());
Gui/CommandS  …[truncated]
Fable
⚙ Bash {"command": "cd src; echo \"=== Help.py lines 440-520 (the webengine tab render path) ===\"; sed -n '425,520p' Mod/Help/Help.py", "description": "Read Help.py webengine render path"}
tool result
=== Help.py lines 440-520 (the webengine tab render path) ===
    return html


def add_preferences_page():
    """adds the Help preferences page to the UI"""

    import FreeCADGui

    page = os.path.join(os.path.dirname(__file__), "dlgPreferencesHelp.ui")
    FreeCADGui.addPreferencePage(page, QT_TRANSLATE_NOOP("QObject", "General"))


def add_language_path():
    """registers the Help translations to FreeCAD"""

    import FreeCADGui
    import Help_rc

    FreeCADGui.addLanguagePath(":/tran  …[truncated]
Fable
thinking
I need to trace through the C++ help routing in MainWindow and understand how it integrates with the Assistant, then compare that against the Python fallback behavior in Help.py to see how documentation should work on WebAssembly.
Fable
⚙ Bash {"command": "cd src; echo \"=== MainWindow::showDocumentation 1184-1245 ===\"; sed -n '1184,1245p' Gui/MainWindow.cpp", "description": "Read showDocumentation impl"}
tool result
=== MainWindow::showDocumentation 1184-1245 ===
void MainWindow::showDocumentation(const QString& help)
{
    Base::PyGILStateLocker lock;
    try {
        PyObject* module = PyImport_ImportModule("Help");
        if (module) {
            Py_DECREF(module);
            Gui::Command::addModule(Gui::Command::Gui, "Help");
            Gui::Command::doCommand(Gui::Command::Gui, "Help.show(\"%s\")", help.toStdString().c_str());
        }
    }
    catch (const Base::Exception& e) {
        e.report  …[truncated]
Fable
⚙ Bash {"command": "cd src; echo \"=== OpenURLInBrowser 340-400 ===\"; sed -n '340,400p' Gui/OnlineDocumentation.cpp", "description": "Read OpenURLInBrowser impl"}
tool result
=== OpenURLInBrowser 340-400 ===
void StdCmdPythonHelp::activated(int iMsg)
{
    Q_UNUSED(iMsg);
    // try to open a connection over this port
    const qint16 port = 7465;
    if (!this->server) {
        this->server = new HttpServer();
    }

    // if server is not yet running try to open one
    if (this->server->isListening()
        || this->server->listen(QHostAddress(QHostAddress::LocalHost), port)) {
        std::string url = "http://localhost:";
        url += std::to_s  …[truncated]
Fable
thinking
I'm realizing that Python's webbrowser module won't work reliably under emscripten since there's typically no registered browser, which would trigger a modal error dialog—not ideal. Instead, I should use emscripten's direct JavaScript approach with window.open or leverage Qt's QDesktopServices::openUrl, which handles WebAssembly environments more gracefully.

Let me trace through the codebase to see what other commands do—checking CommandStd, StdCmdOnlineHelpWebsite, and the OnlineDocumentation's HttpServer setup (which relies on localhost:7465 via QTcpServer, something that won't work on wasm anyway). I should also verify whether the Start module actually avoids WebEngine and confirm what S  …
Fable
⚙ Bash {"command": "cd src; echo \"=== StartView webengine check ===\"; grep -niE \"webengine|qwebengine|QTextBrowser|QWebView\" Mod/Start/Gui/StartView.cpp Mod/Start/Gui/StartView.h; echo \"(empty = none)\"; echo \"=== DlgReport / ReportView ===\…
tool result
=== StartView webengine check ===
(empty = none)
=== DlgReport / ReportView ===
Gui/CommandStd.cpp
Gui/DockWindowManager.cpp
Gui/MainWindow.cpp
Gui/MainWindow.h
Gui/ReportView.cpp
Gui/OverlayManager.cpp
Gui/ReportView.h
Gui/Workbench.cpp
Gui/resource.cpp
Gui/CMakeLists.txt
=== AboutDialog webengine ===
Gui/Dialogs/DlgAbout.h:28:#include <QTextBrowser>
Gui/Dialogs/DlgAbout.h:69:    QTextBrowser* browser;
Gui/Dialogs/DlgAbout.cpp:36:#include <QTextBrowser>
Gui/Dialogs/DlgAbout.cpp:328:    auto tex  …[truncated]
Fable
⚙ Bash {"command": "cd src; echo \"=== CommandStd 559-620 website+bug ===\"; sed -n '575,620p' Gui/CommandStd.cpp; echo \"=== StdCmdPythonHelp class + HttpServer ===\"; grep -n \"HttpServer\\|class StdCmdPythonHelp\\|StdCmdFreeCADForum\\|StdCmdRep…
tool result
=== CommandStd 559-620 website+bug ===
void StdCmdOnlineHelpWebsite::activated(int iMsg)
{
    Q_UNUSED(iMsg);
    std::string defaulturl
        = QCoreApplication::translate(this->className(), "https://wiki.freecad.org/Online_Help_Toc")
              .toStdString();
    ParameterGrp::handle hURLGrp = App::GetApplication().GetParameterGroupByPath(
        "User parameter:BaseApp/Preferences/Websites"
    );
    std::string url = hURLGrp->GetASCII("OnlineHelp", defaulturl.c_str());
     …[truncated]
Fable
thinking
So the DlgReport and ReportView are actually the report display panels using Qt widgets like QTextBrowser and QTextEdit, not WebEngine. The About dialog also uses QTextBrowser, which works fine on WebAssembly. That means QtWebEngine is only used in one place: the Help module, where it renders documentation in an MDI tab or dock window via QWebEngineView.

When BUILD_HELP is disabled, the Help module isn't available, so the import fails gracefully and the help system becomes a no-op. The Help module has its own fallback that routes to the system browser using Python's webbrowser module if QtWebEngineWidgets can't be imported. Everything else avoids WebEngine entirely — the Web module is a TCP  …
Fable
⚙ Bash {"command": "cd src; echo \"=== Help.py 240-360 (show, openBrowser, checkWebEngine, get_contents) ===\"; sed -n '240,300p' Mod/Help/Help.py", "description": "Read Help.py show/openBrowser/checkWebEngine"}
tool result
=== Help.py 240-360 (show, openBrowser, checkWebEngine, get_contents) ===
            if os.path.exists(os.path.join(location, page + ext)):
                location = os.path.join(location, page + ext)
                break
    return (location, pagename)


def show_browser(url):
    """opens the desktop browser with the given URL"""

    from PySide import QtCore, QtGui

    try:
        ret = QtGui.QDesktopServices.openUrl(QtCore.QUrl(url))
        if not ret:
            # some users reporte  …[truncated]
Fable
⚙ Bash {"command": "cd src; echo \"=== emscripten window.open usage already in tree? ===\"; grep -rniE \"emscripten_run_script|EM_ASM|window.open|QDesktopServices::openUrl\" Gui/ Main/ 2>/dev/null | head -20; echo \"=== WasmInittabGui / inittab He…
tool result
=== emscripten window.open usage already in tree? ===
Gui/CommandMacro.cpp:198:    QDesktopServices::openUrl(url);
Gui/DownloadItem.cpp:408:        QDesktopServices::openUrl(url);
Gui/DownloadItem.cpp:416:    QDesktopServices::openUrl(url);
Gui/Widgets.cpp:828:        QDesktopServices::openUrl(this->_url);
Gui/Dialogs/DlgMacroExecuteImp.cpp:1137:    QDesktopServices::openUrl(url);
Gui/Dialogs/DlgProjectInformationImp.cpp:194:    QDesktopServices::openUrl(QUrl(url, QUrl::TolerantMode));
Gui/D  …[truncated]
Fable
thinking
I need to check the inittab files and their locations, verify whether Start is registered, and understand how show() determines whether to use a tab or system browser by looking at the checkWebEngine logic around lines 200-245. I'm also investigating Qt's QDesktopServices::openUrl behavior in WebAssembly — it uses window.open which is supported, so the best approach for OpenURLInBrowser on wasm would be to replace the Python webbrowser call with QDesktopServices::openUrl since it already works there.
Fable
⚙ Bash {"command": "cd src; echo \"=== Help.py show() 190-245 ===\"; sed -n '190,245p' Mod/Help/Help.py; echo \"=== inittab files ===\"; ls Main/WasmInittab*.cpp 2>/dev/null; grep -niE \"Start|StartGui|Web|Help\" Main/WasmInittabGui.cpp 2>/dev/nul…
tool result
=== Help.py show() 190-245 ===
        # we don't know the URL, using location_url() fallback to the HTML <title> tag
        return location_url(page, page)
    if page.startswith("file://"):
        return (page[7:], "")
    # offline location
    if os.path.exists(page):
        return (page, "")
    page = page.replace(".md", "")
    page = page.replace(" ", "_")
    page = page.replace("wiki/", "")
    page = page.split("#")[0]
    suffix = PREFS.GetString("Suffix", "")
    pagename = ""
    …[truncated]
Fable
thinking
I need to locate the inittab files mentioned in the prompt—they should be in src/Main/ as WasmInittab.cpp and WasmInittabGui.cpp, so let me search for them.
Fable
⚙ Bash {"command": "cd /home/magik6k/lcad-wasm/freecad-port/FreeCAD; find . -iname \"WasmInittab*\" 2>/dev/null; echo \"=== search AppendInittab Start ===\"; grep -rn \"AppendInittab\\|freecadWasmRegisterInittab\" src/Main/ 2>/dev/null | grep -iE …
tool result
=== search AppendInittab Start ===
src/Main/CMakeLists.txt:49:            string(APPEND _regs "    PyImport_AppendInittab(\"${_mod}\", PyInit_${_mod});\n")
=== show() top where checkWebEngine used ===
90:def show(page, view=None, conv=None):
120:        if PREFS.GetBool("optionTab", False) and get_qtwebwidgets():
122:            show_tab(html, baseurl, title, view)
123:        elif PREFS.GetBool("optionDialog", False) and get_qtwebwidgets():
125:            show_dialog(html, baseurl, title, view  …[truncated]
Fable
thinking
I need to trace how the inittab gets generated through CMake and locate where WasmInittab.cpp ends up in the build directory, then verify the Start registration process.
Fable
⚙ Bash {"command": "cd /home/magik6k/lcad-wasm/freecad-port/FreeCAD; sed -n '20,90p' src/Main/CMakeLists.txt", "description": "Read inittab generation logic"}
tool result
    endif()
    if(BUILD_PART_DESIGN)
        list(APPEND FREECAD_WASM_PY_MODULES PartDesign)
        list(APPEND FREECAD_WASM_PY_GUI_MODULES PartDesignGui)
    endif()
    if(BUILD_SPREADSHEET)
        list(APPEND FREECAD_WASM_PY_MODULES Spreadsheet)
        list(APPEND FREECAD_WASM_PY_GUI_MODULES SpreadsheetGui)
    endif()
    if(BUILD_MATERIAL)
        list(APPEND FREECAD_WASM_PY_MODULES Materials)
        list(APPEND FREECAD_WASM_PY_GUI_MODULES MatGui)
    endif()
    if(BUILD_MEASURE)
      …[truncated]
Fable
⚙ Bash {"command": "cd /home/magik6k/lcad-wasm/freecad-port/FreeCAD; echo \"=== Help.py 90-130 show dispatch ===\"; sed -n '90,130p' src/Mod/Help/Help.py", "description": "Help show dispatch full"}
tool result
=== Help.py 90-130 show dispatch ===
def show(page, view=None, conv=None):
    """
    show(page,view=None, conv=None):
    Opens a help viewer and shows the given help page.
    The given help page can be a URL pointing to a markdown or HTML file,
    a name page / command name, or a file path pointing to a markdown
    or HTML file. If view is given (an instance of openBrowserHTML.HelpPage or
    any other object with a 'setHtml()' method), the page will be
    rendered there, otherwise a new   …[truncated]
Fable
thinking
I'm realizing the C++ path for OpenURLInBrowser delegates to Python's webbrowser module, but on WebAssembly with Emscripten's CPython, the webbrowser module has no registered browsers—so it throws an error that gets caught and shows a "No Browser" modal dialog. The better approach is to route through QDesktopServices::openUrl instead.

Now I need to check the includes and guards in OnlineDocumentation.cpp to write the patch correctly—I'll need to add the QDesktopServices header and wrap the fix with an __EMSCRIPTEN__ preprocessor guard. I should also verify how HttpServer and StdCmdPythonHelp are guarded to ensure consistency.
Fable
⚙ Bash {"command": "cd /home/magik6k/lcad-wasm/freecad-port/FreeCAD/src; echo \"=== OnlineDocumentation.cpp includes ===\"; sed -n '24,60p' Gui/OnlineDocumentation.cpp; echo \"=== HttpServer class + listen ===\"; grep -n \"class HttpServer\\|QTcpS…
tool result
=== OnlineDocumentation.cpp includes ===
#include <QApplication>
#include <QBuffer>
#include <QImageWriter>
#include <QMessageBox>
#include <QTcpSocket>


#include <Base/Interpreter.h>
#include <Base/Exception.h>

#include "OnlineDocumentation.h"
#include "MainWindow.h"


using namespace Gui;

// the favicon
// clang-format off
// NOLINTBEGIN
static const unsigned int navicon_data_len = 318;
static const unsigned char navicon_data[] = {
    0x00,0x00,0x01,0x00,0x01,0x00,0x10  …[truncated]
Fable
thinking
I've confirmed that QtWebEngine has no WebAssembly port, and the Web module here refers to the TCP AppServer rather than the browser workbench. The old BrowserView/WebGui that relied on WebEngine was removed upstream and replaced by Mod/Help. Now I'm checking whether anything in the compiled Gui actually links against Qt WebEngine by looking through the CMakeLists configuration.
Fable
⚙ Bash {"command": "cd /home/magik6k/lcad-wasm/freecad-port/FreeCAD; grep -rniE \"WebEngine|WebKit|Qt6WebEngine|WebEngineWidgets|WebEngineCore\" cMake/ src/ --include=*.cmake --include=CMakeLists.txt 2>/dev/null | grep -vi translations | head; ech…
tool result
cMake/FreeCAD_Helpers/SetupShibokenAndPyside.cmake:102:            file(WRITE ${CMAKE_BINARY_DIR}/Ext/PySide/QtWebEngineWidgets.py  "from PySide${PYSIDE_MAJOR_VERSION}.QtWebEngineWidgets import *\n")
cMake/FreeCAD_Helpers/SetupShibokenAndPyside.cmake:105:            file(WRITE ${CMAKE_BINARY_DIR}/Ext/PySide/QtWebEngineWidgets.py  "from PySide${PYSIDE_MAJOR_VERSION}.QtWebEngineWidgets import *\n"
cMake/FreeCAD_Helpers/SetupShibokenAndPyside.cmake:106:                                                …[truncated]
Fable
thinking
The WebEngine dependency only comes through the PySide shim, which generates a passthrough module that isn't created when FREECAD_USE_PYSIDE is disabled. Since PySide isn't available in this configuration, there's no C++ compile or link dependency on WebEngine at all, so the GUI builds successfully without it. Now I should check the SetupShibokenAndPyside section to include it in my plan.
Fable
⚙ Bash {"command": "cd /home/magik6k/lcad-wasm/freecad-port/FreeCAD; sed -n '90,110p' cMake/FreeCAD_Helpers/SetupShibokenAndPyside.cmake", "description": "Read pyside webengine shim context"}
tool result
                                "#QCoreApplication.UnicodeUTF8=1\n")
    file(WRITE ${CMAKE_BINARY_DIR}/Ext/PySide/QtNetwork.py  "from PySide${PYSIDE_MAJOR_VERSION}.QtNetwork import *\n")
    if(BUILD_GUI)
        file(WRITE ${CMAKE_BINARY_DIR}/Ext/PySide/QtGui.py  "from PySide${PYSIDE_MAJOR_VERSION}.QtGui import *\n"
                                    "from PySide${PYSIDE_MAJOR_VERSION}.QtWidgets import *\n"
                                    "QHeaderView.setResizeMode = QHeaderView.setSectio  …[truncated]
Fable
thinking
I'm mapping out the deliverables now—I need to create a directory structure with a plan document and a patch file for OnlineDocumentation.cpp, plus potentially a fallback for Help.py. Looking at what needs to be addressed, Help.py is the only place that actually uses QtWebEngine, specifically in the `openBrowserHTML()` function where it creates a QWebEngineView and QWebEnginePage to display documentation.

The Help module is guarded by a check that returns False if PySide's QtWebEngineWidgets can't be imported, and since BUILD_HELP is OFF and PySide isn't available in the wasm build, that guard will prevent the WebEngine code from running anyway. The fallback uses `show_browser` which routes  …
Fable
I now have a complete, code-grounded picture. Let me write the deliverables.
Fable
⚙ Bash {"command": "mkdir -p /home/magik6k/lcad-wasm/porting/webengine-stub; echo created", "description": "Create output dir"}
tool result
created
Fable
⚙ Bash {"command": "cd /home/magik6k/lcad-wasm/freecad-port/FreeCAD/src; echo \"=== StdCmdPythonHelp registration + class def ===\"; grep -n \"StdCmdPythonHelp\\|class HttpServer\" Gui/OnlineDocumentation.cpp Gui/OnlineDocumentation.h Gui/CommandS…
tool result
=== StdCmdPythonHelp registration + class def ===
Gui/OnlineDocumentation.h:67:class HttpServer: public QTcpServer
Gui/OnlineDocumentation.h:89:class StdCmdPythonHelp: public Command
Gui/OnlineDocumentation.h:92:    StdCmdPythonHelp();
Gui/OnlineDocumentation.h:93:    ~StdCmdPythonHelp() override;
Gui/OnlineDocumentation.h:96:        return "Gui::StdCmdPythonHelp";
Gui/OnlineDocumentation.cpp:318:/* TRANSLATOR Gui::StdCmdPythonHelp */
Gui/OnlineDocumentation.cpp:320:StdCmdPythonHelp::StdCm  …[truncated]
Fable
Now I'll write the plan and patch files.
Fable
⚙ Write {"file_path": "/home/magik6k/lcad-wasm/porting/webengine-stub/plan.md", "content": "# Wasm port plan — QtWebEngine-dependent surfaces (slug: `webengine-stub`)\n\n**Verdict:** QtWebEngine has **no wasm port**, but FreeCAD's C++ GUI has **zer…
tool result
File created successfully at: /home/magik6k/lcad-wasm/porting/webengine-stub/plan.md (file state is current in your context — no need to Read it back)
Fable
Now the patch files.
Fable
⚙ Bash {"command": "mkdir -p /home/magik6k/lcad-wasm/porting/webengine-stub/patches\ncd /home/magik6k/lcad-wasm/freecad-port/FreeCAD/src; sed -n '365,391p' Gui/OnlineDocumentation.cpp; echo \"=== 340-364 ===\"; sed -n '340,364p' Gui/OnlineDocument…
tool result
bool Gui::OpenURLInBrowser(const char* URL)
{
    // The webbrowser Python module allows one to start the system browser in an OS-independent way
    Base::PyGILStateLocker lock;
    try {
        PyObject* module = PyImport_ImportModule("webbrowser");
        if (module) {
            Py::Module mod(module, true);
            mod.callMemberFunction("open", Py::TupleN(Py::String(URL)));
            return true;
        }

        throw Py::Exception();
    }
    catch (Py::Exceptio  …[truncated]
Fable
⚙ Write {"file_path": "/home/magik6k/lcad-wasm/porting/webengine-stub/patches/01-OpenURLInBrowser-wasm.diff", "content": "--- a/src/Gui/OnlineDocumentation.cpp\n+++ b/src/Gui/OnlineDocumentation.cpp\n@@ -24,6 +24,8 @@\n #include <QApplication>\n #i…
tool result
File created successfully at: /home/magik6k/lcad-wasm/porting/webengine-stub/patches/01-OpenURLInBrowser-wasm.diff (file state is current in your context — no need to Read it back)
Fable
⚙ Write {"file_path": "/home/magik6k/lcad-wasm/porting/webengine-stub/patches/02-PythonHelp-wasm.diff", "content": "--- a/src/Gui/OnlineDocumentation.cpp\n+++ b/src/Gui/OnlineDocumentation.cpp\n@@ -338,6 +338,14 @@\n void StdCmdPythonHelp::activate…
tool result
File created successfully at: /home/magik6k/lcad-wasm/porting/webengine-stub/patches/02-PythonHelp-wasm.diff (file state is current in your context — no need to Read it back)
Fable
⚙ Write {"file_path": "/home/magik6k/lcad-wasm/porting/webengine-stub/patches/03-hide-pythonhelp-command-wasm.diff", "content": "--- a/src/Gui/CommandStd.cpp\n+++ b/src/Gui/CommandStd.cpp\n@@ -1065,7 +1065,9 @@\n rcCmdMgr.addCommand(new StdCmdO…
tool result
File created successfully at: /home/magik6k/lcad-wasm/porting/webengine-stub/patches/03-hide-pythonhelp-command-wasm.diff (file state is current in your context — no need to Read it back)
Fable
thinking
I've finished putting together all the deliverables and can now provide the structured summary.
Fable
All deliverables written. Returning the structured summary.
Fable
⚙ StructuredOutput {"slug": "webengine-stub", "title": "QtWebEngine-dependent surfaces", "feasibility": "config-only", "oneLineVerdict": "QtWebEngine has no wasm port, but FreeCAD's C++ GUI has zero compile/link dependency on it; the only consumer (Mod/Help/H…
tool result
Structured output provided successfully