Fix ESLint prefer-nullish-coalescing warnings

Author: AnastasiiaBalenko

.changeset/serious-ducks-check.md

@@ -0,0 +1,5 @@
+---
+'@guardian/support-dotcom-components': patch
+---
+
+prefer-nullish-coalescing lint rule violations fix

eslint-suppressions.json

@@ -17,9 +17,6 @@
     "@typescript-eslint/restrict-template-expressions": {
       "count": 1
     },
-    "@typescript-eslint/prefer-nullish-coalescing": {
-      "count": 2
-    },
     "@typescript-eslint/no-unsafe-assignment": {
       "count": 3
     },
@@ -74,16 +71,6 @@
       "count": 1
     }
   },
-  "src/server/lib/targeting.ts": {
-    "@typescript-eslint/prefer-nullish-coalescing": {
-      "count": 1
-    }
-  },
-  "src/server/lib/tracking.ts": {
-    "@typescript-eslint/prefer-nullish-coalescing": {
-      "count": 1
-    }
-  },
   "src/server/middleware/errorHandling.ts": {
     "@typescript-eslint/no-unsafe-assignment": {
       "count": 1
@@ -102,9 +89,6 @@
   "src/server/selection/ab.ts": {
     "@typescript-eslint/no-unnecessary-condition": {
       "count": 1
-    },
-    "@typescript-eslint/prefer-nullish-coalescing": {
-      "count": 1
     }
   },
   "src/server/selection/epsilonGreedySelection.ts": {
@@ -144,24 +128,13 @@
     }
   },
   "src/server/tests/epics/epicSelection.ts": {
-    "@typescript-eslint/prefer-nullish-coalescing": {
-      "count": 4
-    },
     "@typescript-eslint/no-unnecessary-condition": {
       "count": 1
     }
   },
-  "src/server/tests/gutters/gutterSelection.ts": {
-    "@typescript-eslint/prefer-nullish-coalescing": {
-      "count": 2
-    }
-  },
   "src/server/tests/headers/headerSelection.ts": {
     "@typescript-eslint/no-unnecessary-condition": {
       "count": 2
-    },
-    "@typescript-eslint/prefer-nullish-coalescing": {
-      "count": 2
     }
   },
   "src/server/utils/logging.ts": {
@@ -197,9 +170,6 @@
     }
   },
   "src/shared/lib/geolocation.ts": {
-    "@typescript-eslint/prefer-nullish-coalescing": {
-      "count": 1
-    },
     "@typescript-eslint/no-unnecessary-condition": {
       "count": 1
     }

src/server/api/epicRouter.ts

@@ -96,7 +96,7 @@ export const buildEpicRouter = (
             return {};
         }
 
-        const targetingMvtId = targeting.mvtId || 1;
+        const targetingMvtId = targeting.mvtId ?? 1;
 
         const tests =
             type === 'ARTICLE'
@@ -166,7 +166,7 @@ export const buildEpicRouter = (
             abTestName: test.name,
             abTestVariant: variant.name,
             campaignCode: buildEpicCampaignCode(test, variant),
-            campaignId: `epic_${test.campaignId || test.name}`,
+            campaignId: `epic_${test.campaignId ?? test.name}`,
             componentType: 'ACQUISITIONS_EPIC',
             products: ['CONTRIBUTION', 'MEMBERSHIP_SUPPORTER'],
             labels: test.isSuperMode ? ['SUPER_MODE'] : undefined,

src/server/lib/targeting.ts

@@ -57,7 +57,7 @@ export const shouldThrottle = (
 };
 
 export const shouldNotRenderEpic = (meta: EpicTargeting): boolean => {
-    const section = meta.sectionId || meta.sectionName;
+    const section = meta.sectionId ?? meta.sectionName;
     const isLowValueSection = !!section && lowValueSections.includes(section);
     const isLowValueTag = lowValueTags.some((id) => meta.tags.some((pageTag) => pageTag.id === id));
 

src/server/lib/tracking.ts

@@ -10,7 +10,7 @@ import type {
 const campaignPrefix = 'gdnwb_copts_memco';
 
 export const buildEpicCampaignCode = (test: EpicTest, variant: EpicVariant): string =>
-    `${campaignPrefix}_${test.campaignId || test.name}_${variant.name}`;
+    `${campaignPrefix}_${test.campaignId ?? test.name}_${variant.name}`;
 
 export const buildBannerCampaignCode = (test: BannerTest, variant: BannerVariant): string =>
     `${test.name}_${variant.name}`;

src/server/selection/ab.ts

@@ -112,7 +112,7 @@ export const selectAmountsTestVariant = (
 
     // Test is running and user has been successfully assigned to a control/variant
     return {
-        testName: liveTestName || `${testName}_AB_TEST`,
+        testName: liveTestName ?? `${testName}_AB_TEST`,
         ...variant,
     };
 };

src/server/tests/epics/epicSelection.ts

@@ -109,7 +109,7 @@ export const withinMaxViews = (log: EpicViewLog, now: Date = new Date()): Filter
 
         const testId = test.useLocalViewLog ? test.name : undefined;
 
-        return !shouldThrottle(log, test.maxViews || defaultMaxViews, testId, now);
+        return !shouldThrottle(log, test.maxViews ?? defaultMaxViews, testId, now);
     },
 });
 
@@ -203,9 +203,9 @@ export const findTestAndVariant = (
             hasCountryCode,
             isCountryTargetedForEpic,
             // For the super mode pass, we treat all tests as "always ask" so disable this filter
-            ...(isSuperModePass ? [] : [withinMaxViews(targeting.epicViewLog || [])]),
+            ...(isSuperModePass ? [] : [withinMaxViews(targeting.epicViewLog ?? [])]),
             respectArticleCountOptOut,
-            withinArticleViewedSettings(targeting.weeklyArticleHistory || []),
+            withinArticleViewedSettings(targeting.weeklyArticleHistory ?? []),
             deviceTypeMatchesFilter(userDeviceType),
             correctSignedInStatusFilter,
             momentumMatches,
@@ -278,7 +278,7 @@ function selectEpicVariant(
     banditData: BanditData[],
     targeting: EpicTargeting,
 ): Result {
-    const result = selectVariant<EpicVariant, EpicTest>(test, targeting.mvtId || 1, banditData);
+    const result = selectVariant<EpicVariant, EpicTest>(test, targeting.mvtId ?? 1, banditData);
     return {
         result,
     };

src/server/tests/gutters/gutterSelection.ts

@@ -65,7 +65,7 @@ export const selectBestTest = (
     return {
         test: selectedTest,
         variant: selectedVariant,
-        moduleName: selectedVariant.moduleName || moduleName,
+        moduleName: selectedVariant.moduleName ?? moduleName,
     };
 };
 
@@ -84,7 +84,7 @@ const getForcedVariant = (
         return {
             test,
             variant,
-            moduleName: variant.moduleName || moduleName,
+            moduleName: variant.moduleName ?? moduleName,
         };
     }
     return null;

src/server/tests/headers/headerSelection.ts

@@ -379,7 +379,7 @@ export const selectBestTest = (
     return {
         test: selectedTest,
         variant: selectedVariant,
-        moduleName: selectedVariant.moduleName || moduleName,
+        moduleName: selectedVariant.moduleName ?? moduleName,
     };
 };
 
@@ -398,7 +398,7 @@ const getForcedVariant = (
         return {
             test,
             variant,
-            moduleName: variant.moduleName || moduleName,
+            moduleName: variant.moduleName ?? moduleName,
         };
     }
     return null;

src/shared/lib/geolocation.ts

@@ -576,7 +576,7 @@ export const countryCodeToCountryGroupId = (countryCode?: string): CountryGroupI
     const foundCountryGroupId = availableCountryGroupIds.find((countryGroupId) =>
         countryGroups[countryGroupId].countries.includes(countryCode ?? ''),
     );
-    return foundCountryGroupId || 'International';
+    return foundCountryGroupId ?? 'International';
 };
 
 export const inTargetedCountry = (