chore: Fix downstream build failures introduced by #4514

src/icon-provider/__tests__/icon-provider.test.tsx

@@ -8,6 +8,7 @@ import Icon, { IconProps } from '../../../lib/components/icon';
 import IconProvider, { IconProviderProps } from '../../../lib/components/icon-provider';
 import wrapper from '../../../lib/components/test-utils/dom';
 import generatedIcons from '../../icon/generated/icons';
+import { InternalIconContext, InternalIconContextValue } from '../../icon-provider/context';
 import customCSSPropertiesMap from '../../internal/generated/custom-css-properties';
 
 const CUSTOM_SVG = (
@@ -417,4 +418,61 @@ describe('Icon Provider', () => {
       expect(secondIcon).toStrictEqual(expectedSvg);
     });
   });
+
+  describe('missing context fields (null guard)', () => {
+    it('renders without crashing when no IconProvider is present', () => {
+      const { container } = render(<Icon name="calendar" size="normal" />);
+      expect(wrapper(container).findIcon()).not.toBeNull();
+    });
+
+    it('renders without crashing when sizeOverrides is undefined in context', () => {
+      const staleContext = { icons: generatedIcons, strokeWidthOverrides: {} } as InternalIconContextValue;
+      const { container } = render(
+        <InternalIconContext.Provider value={staleContext}>
+          <Icon name="calendar" size="normal" />
+        </InternalIconContext.Provider>
+      );
+      expect(wrapper(container).findIcon()).not.toBeNull();
+    });
+
+    it('renders without crashing when strokeWidthOverrides is undefined in context', () => {
+      const staleContext = { icons: generatedIcons, sizeOverrides: {} } as InternalIconContextValue;
+      const { container } = render(
+        <InternalIconContext.Provider value={staleContext}>
+          <Icon name="calendar" size="normal" />
+        </InternalIconContext.Provider>
+      );
+      expect(wrapper(container).findIcon()).not.toBeNull();
+    });
+
+    it('renders without crashing when both sizeOverrides and strokeWidthOverrides are undefined in context', () => {
+      const staleContext = { icons: generatedIcons } as InternalIconContextValue;
+      const { container } = render(
+        <InternalIconContext.Provider value={staleContext}>
+          <Icon name="calendar" size="normal" />
+        </InternalIconContext.Provider>
+      );
+      expect(wrapper(container).findIcon()).not.toBeNull();
+    });
+
+    it('still applies strokeWidths when sizeOverrides is an empty map', () => {
+      const { container } = render(
+        <IconProvider icons={{}} strokeWidths={{ normal: 2 }}>
+          <Icon name="calendar" size="normal" />
+        </IconProvider>
+      );
+      const iconEl = wrapper(container).findIcon()!.getElement();
+      expect(iconEl.style.getPropertyValue(customCSSPropertiesMap.iconStrokeWidthOverride)).toBe('2px');
+    });
+
+    it('still applies sizes when strokeWidthOverrides is an empty map', () => {
+      const { container } = render(
+        <IconProvider icons={{}} sizes={{ normal: 12 }}>
+          <Icon name="calendar" size="normal" />
+        </IconProvider>
+      );
+      const iconEl = wrapper(container).findIcon()!.getElement();
+      expect(iconEl.style.getPropertyValue(customCSSPropertiesMap.iconSizeOverride)).toBe('12px');
+    });
+  });
 });

src/icon/internal.tsx

@@ -73,12 +73,19 @@ function computeSizeOverrides({
   strokeWidthOverrides,
   iconSize,
 }: {
-  sizeOverrides: Partial<Record<string, number>>;
-  strokeWidthOverrides: Partial<Record<string, number>>;
+  sizeOverrides: Partial<Record<string, number>> | undefined;
+  strokeWidthOverrides: Partial<Record<string, number>> | undefined;
   iconSize: string;
 }): SizeOverrideResult {
   const result: SizeOverrideResult = {};
 
+  if (!sizeOverrides) {
+    sizeOverrides = {};
+  }
+  if (!strokeWidthOverrides) {
+    strokeWidthOverrides = {};
+  }
+
   const targetSizePx = sizeOverrides[iconSize];
   if (targetSizePx !== undefined) {
     result.size = targetSizePx;