Fix cyclic import issue in plotpy.tools module

Author: PierreRaybaut

CHANGELOG.md

@@ -1,5 +1,18 @@
 # Changelog #
 
+## Version 2.4.3 ##
+
+In this release, test coverage is 79%.
+
+🛠️ Bug fixes:
+
+* Fix cyclic import in `plotpy.tools` module:
+  * Some tools in `plotpy.tools` subpackage were importing the `plotpy.plot` module,
+    which was importing the `plotpy.tools` module, causing a cyclic import issue
+  * This is now fixed by introducing new constants for axis IDs in the
+    `plotpy.constants` module, and using them everywhere in the code, thus avoiding
+    to import the `plotpy.plot` module just to get the axis IDs
+
 ## Version 2.4.2 ##
 
 In this release, test coverage is 79%.

plotpy/constants.py

@@ -16,6 +16,14 @@
 
 from plotpy.config import _
 
+# ===============================================================================
+# Plot axes
+# ===============================================================================
+
+#: ID of the x axis
+AXIS_IDS = Y_LEFT, Y_RIGHT, X_BOTTOM, X_TOP = range(4)
+
+
 # ===============================================================================
 # Plot types
 # ===============================================================================

plotpy/items/image/misc.py

@@ -13,6 +13,7 @@
 
 from plotpy import io
 from plotpy.config import _
+from plotpy.constants import X_BOTTOM, Y_LEFT
 from plotpy.coords import axes_to_canvas
 from plotpy.interfaces import (
     IBaseImageItem,
@@ -538,7 +539,7 @@ def get_plot_qrect(plot: qwt.plot.QwtPlot, p0: QPointF, p1: QPointF) -> QRectF:
     Returns:
         Plot rectangle
     """
-    ax, ay = plot.X_BOTTOM, plot.Y_LEFT
+    ax, ay = X_BOTTOM, Y_LEFT
     p0x, p0y = plot.invTransform(ax, p0.x()), plot.invTransform(ay, p0.y())
     p1x, p1y = plot.invTransform(ax, p1.x() + 1), plot.invTransform(ay, p1.y() + 1)
     return QC.QRectF(p0x, p0y, p1x - p0x, p1y - p0y)

plotpy/panels/contrastadjustment.py

@@ -28,7 +28,7 @@
 from qtpy import QtWidgets as QW
 
 from plotpy.config import CONF, IS_DARK, _
-from plotpy.constants import ID_CONTRAST, PlotType
+from plotpy.constants import ID_CONTRAST, Y_LEFT, Y_RIGHT, PlotType
 from plotpy.interfaces import IPanel, IVoiImageItemType
 from plotpy.items import HistogramItem, XRangeSelection
 from plotpy.lutrange import lut_range_threshold
@@ -61,7 +61,7 @@ class LevelsHistogram(BasePlot):
     #: the base plot class (see :py:attr:`.BasePlot.SIG_LUT_CHANGED`).
     SIG_VOI_CHANGED = QC.Signal()
 
-    def __init__(self, parent: QWidget = None) -> None:
+    def __init__(self, parent: QWidget | None = None) -> None:
         super().__init__(
             parent=parent,
             options=BasePlotOptions(title="", section="histogram", type="curve"),
@@ -82,8 +82,8 @@ def __init__(self, parent: QWidget = None) -> None:
         self.set_active_item(self.range)
 
         self.setMinimumHeight(80)
-        self.setAxisMaxMajor(self.Y_LEFT, 5)
-        self.setAxisMaxMinor(self.Y_LEFT, 0)
+        self.setAxisMaxMajor(Y_LEFT, 5)
+        self.setAxisMaxMinor(Y_LEFT, 0)
 
         if parent is None:
             self.set_axis_title("bottom", "Levels")
@@ -255,7 +255,7 @@ def axis_parameters_changed(self, plot: BasePlot, axis_id: int) -> None:
         Args:
             axis_id: axis ID
         """
-        if axis_id == BasePlot.Y_RIGHT:
+        if axis_id == Y_RIGHT:
             # Colormap bounds changed, we need to update the range accordingly:
             self.active_item_changed(plot)
 

plotpy/panels/csection/csitem.py

@@ -10,6 +10,7 @@
 from qtpy import QtCore as QC
 
 from plotpy.config import _
+from plotpy.constants import X_BOTTOM, Y_LEFT
 from plotpy.coords import axes_to_canvas, canvas_to_axes
 from plotpy.interfaces import IBasePlotItem
 from plotpy.items.curve.errorbar import ErrorBarCurveItem
@@ -96,7 +97,7 @@ def get_plot_y_section(obj, apply_lut=False):
     """
     x0, _y0 = get_object_coordinates(obj)
     plot = obj.plot()
-    ymap = plot.canvasMap(plot.Y_LEFT)
+    ymap = plot.canvasMap(Y_LEFT)
     yc0, yc1 = ymap.p1(), ymap.p2()
     if plot.get_axis_direction("left"):
         yc1, yc0 = yc0, yc1
@@ -361,9 +362,9 @@ def update_scale(self):
         """ """
         plot = self.plot()
         if self.orientation() == QC.Qt.Orientation.Vertical:
-            axis_id = plot.Y_LEFT
+            axis_id = Y_LEFT
         else:
-            axis_id = plot.X_BOTTOM
+            axis_id = X_BOTTOM
         source = self.get_source_image()
         sdiv = source.plot().axisScaleDiv(axis_id)
         plot.setAxisScale(axis_id, sdiv.lowerBound(), sdiv.upperBound())

plotpy/panels/csection/csplot.py

@@ -9,15 +9,14 @@
 from qtpy import QtWidgets as QW
 
 from plotpy.config import CONF, _
-from plotpy.constants import LUT_MAX, PlotType
+from plotpy.constants import AXIS_IDS, LUT_MAX, X_BOTTOM, Y_LEFT, PlotType
 from plotpy.interfaces import ICSImageItemType
 from plotpy.panels.csection.csitem import (
     LineCrossSectionItem,
     ObliqueCrossSectionItem,
     XCrossSectionItem,
     YCrossSectionItem,
 )
-from plotpy.plot.base import BasePlot, BasePlotOptions
 from plotpy.styles.curve import CurveParam
 
 LUT_AXIS_TITLE = _("LUT scale") + (" (0-%d)" % LUT_MAX)
@@ -28,6 +27,7 @@
 
     from plotpy.items import BaseImageItem
     from plotpy.panels.csection.csitem import CrossSectionItem
+    from plotpy.plot.base import BasePlot
 
 
 class BaseCrossSectionPlot(BasePlot):
@@ -49,7 +49,7 @@ class BaseCrossSectionPlot(BasePlot):
     def __init__(self, parent: QWidget | None = None) -> None:
         super().__init__(
             parent=parent,
-            options=BasePlotOptions(title="", section="cross_section", type="curve"),
+            options=dict(title="", section="cross_section", type="curve"),
         )
         self.perimage_mode = True
         self.autoscale_mode = True
@@ -110,7 +110,7 @@ def connect_plot(self, plot: BasePlot) -> None:
         plot.SIG_AXIS_DIRECTION_CHANGED.connect(self.axis_dir_changed)
         plot.SIG_PLOT_AXIS_CHANGED.connect(self.plot_axis_changed)
         self.plot_labels_changed(plot)
-        for axis_id in plot.AXIS_IDS:
+        for axis_id in AXIS_IDS:
             self.axis_dir_changed(plot, axis_id)
         self.items_changed(plot)
 
@@ -364,8 +364,8 @@ def lut_changed(self, plot: BasePlot) -> None:
 
 
 class HorizontalCrossSectionPlot(BaseCrossSectionPlot):
-    CS_AXIS = BasePlot.X_BOTTOM
-    Z_AXIS = BasePlot.Y_LEFT
+    CS_AXIS = X_BOTTOM
+    Z_AXIS = Y_LEFT
 
     def plot_labels_changed(self, plot: BasePlot) -> None:
         """Plot labels have changed
@@ -391,8 +391,8 @@ def axis_dir_changed(self, plot: BasePlot, axis_id: str) -> None:
 
 
 class VerticalCrossSectionPlot(BaseCrossSectionPlot):
-    CS_AXIS = BasePlot.Y_LEFT
-    Z_AXIS = BasePlot.X_BOTTOM
+    CS_AXIS = Y_LEFT
+    Z_AXIS = X_BOTTOM
     Z_MAX_MAJOR = 3
 
     def plot_labels_changed(self, plot: BasePlot) -> None:
@@ -419,7 +419,6 @@ def axis_dir_changed(self, plot: BasePlot, axis_id: str) -> None:
 
 
 class XYCrossSectionMixin:
-
     LABEL_TEXT = _("Enable a marker")
 
     def connect_plot(self, plot: BasePlot) -> None:

plotpy/plot/base.py

@@ -31,6 +31,7 @@
 from qtpy import QtWidgets as QW
 from qtpy.QtPrintSupport import QPrinter
 
+from plotpy import constants as cst
 from plotpy import io
 from plotpy.config import CONF, _
 from plotpy.constants import PARAMETERS_TITLE_ICON, PlotType
@@ -149,14 +150,7 @@ class BasePlot(qwt.QwtPlot):
         options: plot options
     """
 
-    Y_LEFT, Y_RIGHT, X_BOTTOM, X_TOP = (
-        qwt.QwtPlot.yLeft,
-        qwt.QwtPlot.yRight,
-        qwt.QwtPlot.xBottom,
-        qwt.QwtPlot.xTop,
-    )
-    #    # To be replaced by (in the near future):
-    #    Y_LEFT, Y_RIGHT, X_BOTTOM, X_TOP = range(4)
+    Y_LEFT, Y_RIGHT, X_BOTTOM, X_TOP = cst.Y_LEFT, cst.Y_RIGHT, cst.X_BOTTOM, cst.X_TOP
     AXIS_IDS = (Y_LEFT, Y_RIGHT, X_BOTTOM, X_TOP)
     AXIS_NAMES = {"left": Y_LEFT, "right": Y_RIGHT, "bottom": X_BOTTOM, "top": X_TOP}
     AXIS_TYPES = {"lin": qwt.QwtLinearScaleEngine, "log": qwt.QwtLogScaleEngine}
@@ -331,7 +325,7 @@ def __init__(
                 options.yreverse = False
                 self.__autoYReverse = True
 
-        self.colormap_axis = self.Y_RIGHT
+        self.colormap_axis = cst.Y_RIGHT
 
         self.__autoColorBarEnabled = False
         if options.force_colorbar_enabled or self.options.type == PlotType.IMAGE:
@@ -1912,7 +1906,7 @@ def edit_axis_parameters(self, axis_id: int) -> None:
             axis_id (int): the axis ID
         """
         if axis_id != self.colormap_axis:
-            if axis_id in (self.Y_LEFT, self.Y_RIGHT):
+            if axis_id in (cst.Y_LEFT, cst.Y_RIGHT):
                 title = _("Y Axis")
             else:
                 title = _("X Axis")
@@ -2044,11 +2038,11 @@ def get_axis_direction(self, axis_id: int | str) -> bool:
         Return axis direction of increasing values
 
         Args:
-            axis_id (int | str): axis id (BasePlot.Y_LEFT, BasePlot.X_BOTTOM, ...)
+            axis_id: axis id (constants.Y_LEFT, constants.X_BOTTOM, ...)
              or string: 'bottom', 'left', 'top' or 'right'
 
         Returns:
-            bool: False (default)
+            False (default)
         """
         axis_id = self.get_axis_id(axis_id)
         return self.axes_reverse[axis_id]
@@ -2058,8 +2052,8 @@ def set_axis_direction(self, axis_id: int | str, reverse: bool = False) -> None:
         Set axis direction of increasing values
 
         Args:
-            axis_id (int | str): axis id (BasePlot.Y_LEFT, BasePlot.X_BOTTOM, ...)
-                or string: 'bottom', 'left', 'top' or 'right'
+            axis_id: axis id (constants.Y_LEFT, constants.X_BOTTOM, ...)
+             or string: 'bottom', 'left', 'top' or 'right'
             reverse (bool): False (default)
 
         If reverse is False:
@@ -2211,10 +2205,10 @@ def get_current_aspect_ratio(self) -> float | None:
             (this happens when the plot has been shrunk to a size so that the
             width is zero)
         """
-        dx = self.axisScaleDiv(self.X_BOTTOM).range()
-        dy = self.axisScaleDiv(self.Y_LEFT).range()
-        h = self.canvasMap(self.Y_LEFT).pDist()
-        w = self.canvasMap(self.X_BOTTOM).pDist()
+        dx = self.axisScaleDiv(cst.X_BOTTOM).range()
+        dy = self.axisScaleDiv(cst.Y_LEFT).range()
+        h = self.canvasMap(cst.Y_LEFT).pDist()
+        w = self.canvasMap(cst.X_BOTTOM).pDist()
         try:
             return fabs((h * dx) / (w * dy))
         except ZeroDivisionError:
@@ -2260,8 +2254,8 @@ def apply_aspect_ratio(self, full_scale: bool = False) -> None:
             abs(current_aspect - self.__aspect_ratio) < self.EPSILON_ASPECT_RATIO
         ):
             return
-        ymap = self.canvasMap(self.Y_LEFT)
-        xmap = self.canvasMap(self.X_BOTTOM)
+        ymap = self.canvasMap(cst.Y_LEFT)
+        xmap = self.canvasMap(cst.X_BOTTOM)
         h = ymap.pDist()
         w = xmap.pDist()
         dx1, dy1 = xmap.sDist(), fabs(ymap.sDist())

plotpy/plot/plotwidget.py

@@ -15,7 +15,7 @@
 from qtpy.QtWidgets import QWidget  # only to help intersphinx find QWidget
 
 from plotpy.config import _
-from plotpy.constants import PlotType
+from plotpy.constants import X_BOTTOM, Y_LEFT, PlotType
 from plotpy.plot.base import BasePlot, BasePlotOptions
 from plotpy.plot.manager import PlotManager
 
@@ -989,8 +989,8 @@ def add_plot(
         if sync and len(self.subplotwidget.plots) > 1:
             syncaxis = self.manager.synchronize_axis
             for i_plot in range(len(self.subplotwidget.plots) - 1):
-                syncaxis(BasePlot.X_BOTTOM, [plot_id, f"{i_plot + 1}"])
-                syncaxis(BasePlot.Y_LEFT, [plot_id, f"{i_plot + 1}"])
+                syncaxis(X_BOTTOM, [plot_id, f"{i_plot + 1}"])
+                syncaxis(Y_LEFT, [plot_id, f"{i_plot + 1}"])
 
     def get_plots(self) -> list[BasePlot]:
         """Return the plots

plotpy/styles/axes.py

@@ -20,6 +20,7 @@
 from qwt import QwtPlot
 
 from plotpy.config import _
+from plotpy.constants import X_BOTTOM, Y_LEFT, Y_RIGHT
 from plotpy.styles.base import FontItem
 
 if TYPE_CHECKING:
@@ -197,7 +198,7 @@ def update_item(self, item: BaseImageItem) -> None:
         plot.set_plot_limits(self.xmin, self.xmax, self.ymin, self.ymax)
         item.set_lut_range([self.zmin, self.zmax])
         plot.update_colormap_axis(item)
-        for axis_id in (plot.X_BOTTOM, plot.Y_LEFT, plot.Y_RIGHT):
+        for axis_id in (X_BOTTOM, Y_LEFT, Y_RIGHT):
             plot.SIG_AXIS_PARAMETERS_CHANGED.emit(axis_id)
 
     # TODO: remove this method in a future release

plotpy/tests/tools/test_cyclic_import.py

@@ -0,0 +1,30 @@
+# -*- coding: utf-8 -*-
+#
+# Licensed under the terms of the BSD 3-Clause
+# (see plotpy/LICENSE for details)
+
+"""Test cyclic import issue"""
+
+# pylint: disable=import-outside-toplevel
+# pylint: disable=unused-import
+
+
+def test_tools_cyclic_import():
+    """Test cyclic import issue"""
+    # Importing one tool from each module to check if there is a cyclic import issue
+    from plotpy.tools import (
+        AnnotatedPointTool,  # noqa: F401
+        AverageCrossSectionTool,  # noqa: F401
+        CurveStatsTool,  # noqa: F401
+        DoAutoscaleTool,  # noqa: F401
+        ItemCenterTool,  # noqa: F401
+        OpenImageTool,  # noqa: F401
+        PointTool,  # noqa: F401
+        PrintTool,  # noqa: F401
+        RectangularActionTool,  # noqa: F401
+        SelectTool,  # noqa: F401
+    )
+
+
+if __name__ == "__main__":
+    test_tools_cyclic_import()