test(lib): add tests for

src/__tests__/if-run/lib/explain.test.ts

@@ -0,0 +1,86 @@
+import {explain, addExplainData} from '../../../if-run/lib/explain';
+
+describe('lib/explain: ', () => {
+  it('successfully adds explain data if `inputs` and `outputs` of `metadata` are `undefined`.', () => {
+    const mockData = {
+      pluginName: 'divide',
+      metadata: {kind: 'execute', inputs: undefined, outputs: undefined},
+      pluginData: {
+        path: 'builtin',
+        method: 'Divide',
+      },
+    };
+    const expectedResult = {
+      divide: {
+        method: 'Divide',
+        path: 'builtin',
+        inputs: 'undefined',
+        outputs: 'undefined',
+      },
+    };
+
+    addExplainData(mockData);
+    const result = explain();
+    expect.assertions(1);
+    expect(result).toEqual(expectedResult);
+  });
+
+  it('successfully adds explain data if `inputs` and `outputs` of `metadata` are valid data.', () => {
+    const mockData = {
+      pluginName: 'sum',
+      metadata: {
+        kind: 'execute',
+        inputs: {
+          'cpu/energy': {
+            unit: 'kWh',
+            description: 'energy consumed by the cpu',
+          },
+          'network/energy': {
+            unit: 'kWh',
+            description: 'energy consumed by data ingress and egress',
+          },
+        },
+        outputs: {
+          'energy-sum': {
+            unit: 'kWh',
+            description: 'sum of energy components',
+          },
+        },
+      },
+      pluginData: {
+        path: 'builtin',
+        method: 'Sum',
+      },
+    };
+    const expectedResult = {
+      divide: {
+        method: 'Divide',
+        path: 'builtin',
+        inputs: 'undefined',
+        outputs: 'undefined',
+      },
+      sum: {
+        method: 'Sum',
+        path: 'builtin',
+        inputs: {
+          'cpu/energy': {
+            unit: 'kWh',
+            description: 'energy consumed by the cpu',
+          },
+          'network/energy': {
+            unit: 'kWh',
+            description: 'energy consumed by data ingress and egress',
+          },
+        },
+        outputs: {
+          'energy-sum': {unit: 'kWh', description: 'sum of energy components'},
+        },
+      },
+    };
+
+    addExplainData(mockData);
+    const result = explain();
+    expect.assertions(1);
+    expect(result).toEqual(expectedResult);
+  });
+});