fix: Preserve fallthrough variation when cloning test data. (#194)

Author: kinyoklion

packages/shared/sdk-server/__tests__/LDClient.evaluation.test.ts

@@ -34,6 +34,33 @@ describe('given an LDClient with test data', () => {
     client.close();
   });
 
+  it('evaluates a flag which has a fallthrough and a rule', async () => {
+    const testId = 'abcd'.repeat(8);
+    const flagKey = 'testFlag';
+    await td.update(td.flag(flagKey).booleanFlag().variationForAll(true));
+    await td.update(td.flag(flagKey).ifMatch('user', 'testId', testId).thenReturn(false));
+
+    // Evaluate with no testId
+    const flagsState = await client.allFlagsState({
+      kind: 'user',
+      key: 'fake',
+      testId: undefined,
+    });
+
+    const features = flagsState.allValues();
+
+    expect(features[flagKey]).toBeTruthy();
+
+    const flagsStateWithTenant = await client.allFlagsState({
+      kind: 'user',
+      key: testId,
+      testId,
+    });
+
+    const featuresWithTenant = flagsStateWithTenant.allValues();
+    expect(featuresWithTenant[flagKey]).toBeFalsy();
+  });
+
   it('evaluates an existing flag', async () => {
     td.update(td.flag('flagkey').on(true).variations('a', 'b').fallthroughVariation(1));
     expect(await client.variation('flagkey', defaultUser, 'c')).toBe('b');

packages/shared/sdk-server/__tests__/integrations/test_data/TestData.test.ts

@@ -167,6 +167,9 @@ describe('given a TestData instance', () => {
   it('can clone a complex flag configuration', () => {
     const flag = td
       .flag('test-flag')
+      .offVariation(true)
+      .variationForAll(false)
+      .variationForUser('billy', true)
       .ifMatch('user', 'name', 'ben', 'christian')
       .andNotMatch('user', 'country', 'fr')
       .thenReturn(true);
@@ -199,7 +202,14 @@ describe('given a TestData instance', () => {
       },
     ];
 
-    expect(flagCopy.build(1).rules).toEqual(flagRules);
+    const builtFlag = flagCopy.build(1);
+    expect(builtFlag.fallthrough).toEqual({ variation: 1 });
+    expect(builtFlag.offVariation).toEqual(0);
+    expect(builtFlag.variations).toEqual([true, false]);
+    expect(builtFlag.contextTargets).toEqual([
+      { contextKind: 'user', values: ['billy'], variation: 0 },
+    ]);
+    expect(builtFlag.rules).toEqual(flagRules);
   });
 
   it('defaults a new flag to on', () => {

packages/shared/sdk-server/src/integrations/test_data/TestDataFlagBuilder.ts

@@ -42,7 +42,7 @@ export default class TestDataFlagBuilder {
         this.data.offVariation = data.offVariation;
       }
       if (data.fallthroughVariation !== undefined) {
-        this.data.offVariation = data.offVariation;
+        this.data.fallthroughVariation = data.fallthroughVariation;
       }
       if (data.targetsByVariation) {
         this.data.targetsByVariation = JSON.parse(JSON.stringify(data.targetsByVariation));