qgis-mcp-test

name	qgis-mcp-test
description	Verify QGIS plugin code in a live QGIS instance via MCP tools. Test imports, dialog creation, widget visibility, signal wiring, and parameter roundtrips.

QGIS MCP Testing

Verify plugin behavior in a live QGIS instance. Use for any change touching the Processing dialog, parameter wrappers, widget visibility, or plugin loading.

Workflow

1. ./install-dev.sh — copy latest code to QGIS plugin dir
2. mcp_qgis_tool_reload_plugin with plugin_name: comapeo_smp
3. mcp_qgis_tool_execute_code — run test snippets (see patterns below)
4. mcp_qgis_tool_get_message_log with level: warning — check for errors

Test Patterns

Import check

from comapeo_smp.comapeo_smp_dialog import SmpAlgorithmDialog, SmpParametersPanel
print("PASS: import")

Algorithm + dialog creation

from comapeo_smp.comapeo_smp_algorithm import ComapeoMapBuilderAlgorithm
from qgis.PyQt.QtWidgets import QWidget
alg = ComapeoMapBuilderAlgorithm()
alg.initAlgorithm(None)
dialog = alg.createCustomParametersWidget(QWidget())
panel = dialog.mainWidget()
print(f"Wrappers: {len(panel.wrappers)}, Params: {len(panel._param_widgets)}")

Visibility toggling

# Use isHidden() not isVisible() — parent is unshown so isVisible() is always False
from qgis.core import QgsProcessingContext
ctx = QgsProcessingContext()
panel.wrappers['INCLUDE_REGION'].setWidgetValue(True, ctx)
panel._on_region_changed()
print(panel._param_widgets['REGION_EXTENT'][0].isHidden())  # expect False

Signal wiring

fired = {'v': False}
panel.wrappers['INCLUDE_WORLD_BASE_ZOOMS'].widgetValueHasChanged.connect(lambda: fired.update(v=True))
panel.wrappers['INCLUDE_WORLD_BASE_ZOOMS'].setWidgetValue(False, QgsProcessingContext())
print(fired['v'])  # expect True

Parameter roundtrip

params = panel.createProcessingParameters()
print(f"Params: {len(params)}")  # expect 12

When to use

• Offline tests (make test) cover generator logic
• MCP covers the QGIS runtime path (imports, wrappers, widgets, signals)
• Always use after changes to comapeo_smp_dialog.py, comapeo_smp_algorithm.py UI code, or plugin loading