fix(deck.gl): restore legend display for Polygon charts with linear palette and fixed color schemes (#35142)

Co-authored-by: Claude <noreply@anthropic.com>

superset-frontend/plugins/legacy-preset-chart-deckgl/src/layers/Polygon/Polygon.test.tsx

@@ -0,0 +1,355 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+// eslint-disable-next-line import/no-extraneous-dependencies
+import { render, screen } from '@testing-library/react';
+// eslint-disable-next-line import/no-extraneous-dependencies
+import '@testing-library/jest-dom';
+import { supersetTheme, ThemeProvider } from '@superset-ui/core';
+import DeckGLPolygon, { getPoints } from './Polygon';
+import { COLOR_SCHEME_TYPES } from '../../utilities/utils';
+import * as utils from '../../utils';
+
+// Mock the utils functions
+const mockGetBuckets = jest.spyOn(utils, 'getBuckets');
+const mockGetColorBreakpointsBuckets = jest.spyOn(
+  utils,
+  'getColorBreakpointsBuckets',
+);
+
+// Mock DeckGL container and Legend
+jest.mock('../../DeckGLContainer', () => ({
+  DeckGLContainerStyledWrapper: ({ children }: any) => (
+    <div data-testid="deckgl-container">{children}</div>
+  ),
+}));
+
+jest.mock('../../components/Legend', () => ({ categories, position }: any) => (
+  <div
+    data-testid="legend"
+    data-categories={JSON.stringify(categories)}
+    data-position={position}
+  >
+    Legend Mock
+  </div>
+));
+
+const mockProps = {
+  formData: {
+    // Required QueryFormData properties
+    datasource: 'test_datasource',
+    viz_type: 'deck_polygon',
+    // Polygon-specific properties
+    metric: { label: 'population' },
+    color_scheme_type: COLOR_SCHEME_TYPES.linear_palette,
+    legend_position: 'tr',
+    legend_format: '.2f',
+    autozoom: false,
+    mapbox_style: 'mapbox://styles/mapbox/light-v9',
+    opacity: 80,
+    filled: true,
+    stroked: true,
+    extruded: false,
+    line_width: 1,
+    line_width_unit: 'pixels',
+    multiplier: 1,
+    break_points: [],
+    num_buckets: '5',
+    linear_color_scheme: 'blue_white_yellow',
+  },
+  payload: {
+    data: {
+      features: [
+        {
+          population: 100000,
+          polygon: [
+            [0, 0],
+            [1, 0],
+            [1, 1],
+            [0, 1],
+          ],
+        },
+        {
+          population: 200000,
+          polygon: [
+            [2, 2],
+            [3, 2],
+            [3, 3],
+            [2, 3],
+          ],
+        },
+      ],
+      mapboxApiKey: 'test-key',
+    },
+    form_data: {},
+  },
+  setControlValue: jest.fn(),
+  viewport: { longitude: 0, latitude: 0, zoom: 1 },
+  onAddFilter: jest.fn(),
+  width: 800,
+  height: 600,
+  onContextMenu: jest.fn(),
+  setDataMask: jest.fn(),
+  filterState: undefined,
+  emitCrossFilters: false,
+};
+
+describe('DeckGLPolygon bucket generation logic', () => {
+  beforeEach(() => {
+    jest.clearAllMocks();
+    mockGetBuckets.mockReturnValue({
+      '100000 - 150000': { color: [0, 100, 200], enabled: true },
+      '150000 - 200000': { color: [50, 150, 250], enabled: true },
+    });
+    mockGetColorBreakpointsBuckets.mockReturnValue({});
+  });
+
+  const renderWithTheme = (component: React.ReactElement) =>
+    render(<ThemeProvider theme={supersetTheme}>{component}</ThemeProvider>);
+
+  test('should use getBuckets for linear_palette color scheme', () => {
+    const propsWithLinearPalette = {
+      ...mockProps,
+      formData: {
+        ...mockProps.formData,
+        color_scheme_type: COLOR_SCHEME_TYPES.linear_palette,
+      },
+    };
+
+    renderWithTheme(<DeckGLPolygon {...propsWithLinearPalette} />);
+
+    // Should call getBuckets, not getColorBreakpointsBuckets
+    expect(mockGetBuckets).toHaveBeenCalled();
+    expect(mockGetColorBreakpointsBuckets).not.toHaveBeenCalled();
+  });
+
+  test('should use getBuckets for fixed_color color scheme', () => {
+    const propsWithFixedColor = {
+      ...mockProps,
+      formData: {
+        ...mockProps.formData,
+        color_scheme_type: COLOR_SCHEME_TYPES.fixed_color,
+      },
+    };
+
+    renderWithTheme(<DeckGLPolygon {...propsWithFixedColor} />);
+
+    // Should call getBuckets, not getColorBreakpointsBuckets
+    expect(mockGetBuckets).toHaveBeenCalled();
+    expect(mockGetColorBreakpointsBuckets).not.toHaveBeenCalled();
+  });
+
+  test('should use getColorBreakpointsBuckets for color_breakpoints scheme', () => {
+    const propsWithBreakpoints = {
+      ...mockProps,
+      formData: {
+        ...mockProps.formData,
+        color_scheme_type: COLOR_SCHEME_TYPES.color_breakpoints,
+        color_breakpoints: [
+          {
+            minValue: 0,
+            maxValue: 100000,
+            color: { r: 255, g: 0, b: 0, a: 100 },
+          },
+          {
+            minValue: 100001,
+            maxValue: 200000,
+            color: { r: 0, g: 255, b: 0, a: 100 },
+          },
+        ],
+      },
+    };
+
+    mockGetColorBreakpointsBuckets.mockReturnValue({
+      '0 - 100000': { color: [255, 0, 0], enabled: true },
+      '100001 - 200000': { color: [0, 255, 0], enabled: true },
+    });
+
+    renderWithTheme(<DeckGLPolygon {...propsWithBreakpoints} />);
+
+    // Should call getColorBreakpointsBuckets, not getBuckets
+    expect(mockGetColorBreakpointsBuckets).toHaveBeenCalled();
+    expect(mockGetBuckets).not.toHaveBeenCalled();
+  });
+
+  test('should use getBuckets when color_scheme_type is undefined (backward compatibility)', () => {
+    const propsWithUndefinedScheme = {
+      ...mockProps,
+      formData: {
+        ...mockProps.formData,
+        color_scheme_type: undefined,
+      },
+    };
+
+    renderWithTheme(<DeckGLPolygon {...propsWithUndefinedScheme} />);
+
+    // Should call getBuckets for backward compatibility
+    expect(mockGetBuckets).toHaveBeenCalled();
+    expect(mockGetColorBreakpointsBuckets).not.toHaveBeenCalled();
+  });
+
+  test('should use getBuckets for unsupported color schemes (categorical_palette)', () => {
+    const propsWithUnsupportedScheme = {
+      ...mockProps,
+      formData: {
+        ...mockProps.formData,
+        color_scheme_type: COLOR_SCHEME_TYPES.categorical_palette,
+      },
+    };
+
+    renderWithTheme(<DeckGLPolygon {...propsWithUnsupportedScheme} />);
+
+    // Should fall back to getBuckets for unsupported color schemes
+    expect(mockGetBuckets).toHaveBeenCalled();
+    expect(mockGetColorBreakpointsBuckets).not.toHaveBeenCalled();
+  });
+});
+
+describe('DeckGLPolygon Error Handling and Edge Cases', () => {
+  beforeEach(() => {
+    jest.clearAllMocks();
+    mockGetBuckets.mockReturnValue({});
+    mockGetColorBreakpointsBuckets.mockReturnValue({});
+  });
+
+  const renderWithTheme = (component: React.ReactElement) =>
+    render(<ThemeProvider theme={supersetTheme}>{component}</ThemeProvider>);
+
+  test('handles empty features data gracefully', () => {
+    const propsWithEmptyData = {
+      ...mockProps,
+      payload: {
+        ...mockProps.payload,
+        data: {
+          ...mockProps.payload.data,
+          features: [],
+        },
+      },
+    };
+
+    renderWithTheme(<DeckGLPolygon {...propsWithEmptyData} />);
+
+    // Should still call getBuckets with empty data
+    expect(mockGetBuckets).toHaveBeenCalled();
+    expect(mockGetColorBreakpointsBuckets).not.toHaveBeenCalled();
+  });
+
+  test('handles missing color_breakpoints for color_breakpoints scheme', () => {
+    const propsWithMissingBreakpoints = {
+      ...mockProps,
+      formData: {
+        ...mockProps.formData,
+        color_scheme_type: COLOR_SCHEME_TYPES.color_breakpoints,
+        color_breakpoints: undefined,
+      },
+    };
+
+    renderWithTheme(<DeckGLPolygon {...propsWithMissingBreakpoints} />);
+
+    // Should call getColorBreakpointsBuckets even with undefined breakpoints
+    expect(mockGetColorBreakpointsBuckets).toHaveBeenCalledWith(undefined);
+    expect(mockGetBuckets).not.toHaveBeenCalled();
+  });
+
+  test('handles null legend_position correctly', () => {
+    const propsWithNullLegendPosition = {
+      ...mockProps,
+      formData: {
+        ...mockProps.formData,
+        legend_position: null,
+      },
+    };
+
+    renderWithTheme(<DeckGLPolygon {...propsWithNullLegendPosition} />);
+
+    // Legend should not be rendered when position is null
+    expect(screen.queryByTestId('legend')).not.toBeInTheDocument();
+  });
+});
+
+describe('DeckGLPolygon Legend Integration', () => {
+  beforeEach(() => {
+    jest.clearAllMocks();
+    mockGetBuckets.mockReturnValue({
+      '100000 - 150000': { color: [0, 100, 200], enabled: true },
+      '150000 - 200000': { color: [50, 150, 250], enabled: true },
+    });
+  });
+
+  const renderWithTheme = (component: React.ReactElement) =>
+    render(<ThemeProvider theme={supersetTheme}>{component}</ThemeProvider>);
+
+  test('renders legend with non-empty categories when metric and linear_palette are defined', () => {
+    const { container } = renderWithTheme(<DeckGLPolygon {...mockProps} />);
+
+    // Verify the component renders and calls the correct bucket function
+    expect(mockGetBuckets).toHaveBeenCalled();
+    expect(mockGetColorBreakpointsBuckets).not.toHaveBeenCalled();
+
+    // Verify the legend mock was rendered with non-empty categories
+    const legendElement = container.querySelector('[data-testid="legend"]');
+    expect(legendElement).toBeTruthy();
+    const categoriesAttr = legendElement?.getAttribute('data-categories');
+    const categoriesData = JSON.parse(categoriesAttr || '{}');
+    expect(Object.keys(categoriesData)).toHaveLength(2);
+  });
+
+  test('does not render legend when metric is null', () => {
+    const propsWithoutMetric = {
+      ...mockProps,
+      formData: {
+        ...mockProps.formData,
+        metric: null,
+      },
+    };
+
+    renderWithTheme(<DeckGLPolygon {...propsWithoutMetric} />);
+
+    // Legend should not be rendered when no metric is defined
+    expect(screen.queryByTestId('legend')).not.toBeInTheDocument();
+  });
+});
+
+describe('getPoints utility', () => {
+  test('extracts points from polygon data', () => {
+    const data = [
+      {
+        polygon: [
+          [0, 0],
+          [1, 0],
+          [1, 1],
+          [0, 1],
+        ],
+      },
+      {
+        polygon: [
+          [2, 2],
+          [3, 2],
+          [3, 3],
+          [2, 3],
+        ],
+      },
+    ];
+
+    const points = getPoints(data);
+
+    expect(points).toHaveLength(8); // 4 points per polygon * 2 polygons
+    expect(points[0]).toEqual([0, 0]);
+    expect(points[4]).toEqual([2, 2]);
+  });
+});

superset-frontend/plugins/legacy-preset-chart-deckgl/src/layers/Polygon/Polygon.tsx

@@ -335,9 +335,10 @@ const DeckGLPolygon = (props: DeckGLPolygonProps) => {
   const accessor = (d: JsonObject) => d[metricLabel];
 
   const colorSchemeType = formData.color_scheme_type;
-  const buckets = colorSchemeType
-    ? getColorBreakpointsBuckets(formData.color_breakpoints)
-    : getBuckets(formData, payload.data.features, accessor);
+  const buckets =
+    colorSchemeType === COLOR_SCHEME_TYPES.color_breakpoints
+      ? getColorBreakpointsBuckets(formData.color_breakpoints)
+      : getBuckets(formData, payload.data.features, accessor);
 
   return (
     <div style={{ position: 'relative' }}>