Enhancing the toHaveProperty matcher to support array selection (#1…

…2092)

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - `[jest-core]` Add support for `testResultsProcessor` written in ESM ([#12006](https://github.com/facebook/jest/pull/12006))
 - `[jest-diff, pretty-format]` Add `compareKeys` option for custom sorting of object keys ([#11992](https://github.com/facebook/jest/pull/11992))
+- `[expect]` Enhancing the `toHaveProperty` matcher to support array selection ([#12092](https://github.com/facebook/jest/pull/12092))
 
 ### Fixes
 

docs/ExpectAPI.md

@@ -895,6 +895,16 @@ const houseForSale = {
     wallColor: 'white',
     'nice.oven': true,
   },
+  livingroom: {
+    amenities: [
+      {
+        couch: [
+          ['large', {dimensions: [20, 20]}],
+          ['small', {dimensions: [10, 10]}],
+        ],
+      },
+    ],
+  },
   'ceiling.height': 2,
 };
 
@@ -922,6 +932,10 @@ test('this house has my desired features', () => {
     ['oven', 'stove', 'washer'],
   );
   expect(houseForSale).toHaveProperty(['kitchen', 'amenities', 0], 'oven');
+  expect(houseForSale).toHaveProperty(
+    'livingroom.amenities[0].couch[0][1].dimensions[0]',
+    20,
+  );
   expect(houseForSale).toHaveProperty(['kitchen', 'nice.oven']);
   expect(houseForSale).not.toHaveProperty(['kitchen', 'open']);
 

packages/expect/src/__tests__/__snapshots__/matchers.test.js.snap

@@ -3334,6 +3334,15 @@ Expected value: <g>1</>
 Received value: <r>{"c": {"d": 1}}</>
 `;
 
+exports[`.toHaveProperty() {pass: false} expect({"a": {"b": {"c": {}}}}).toHaveProperty('.a.b.c') 1`] = `
+<d>expect(</><r>received</><d>).</>toHaveProperty<d>(</><g>path</><d>)</>
+
+Expected path: <g>".a.b.c"</>
+Received path: <r>[]</>
+
+Received value: <r>{"a": {"b": {"c": {}}}}</>
+`;
+
 exports[`.toHaveProperty() {pass: false} expect({"a": {"b": {"c": {}}}}).toHaveProperty('a.b.c.d') 1`] = `
 <d>expect(</><r>received</><d>).</>toHaveProperty<d>(</><g>path</><d>)</>
 
@@ -3551,6 +3560,30 @@ Expected path: <g>"memo"</>
 Expected value: not <g>[]</>
 `;
 
+exports[`.toHaveProperty() {pass: true} expect({"a": {"b": [[{"c": [{"d": 1}]}]]}}).toHaveProperty('a.b[0][0].c[0].d', 1) 1`] = `
+<d>expect(</><r>received</><d>).</>not<d>.</>toHaveProperty<d>(</><g>path</><d>, </><g>value</><d>)</>
+
+Expected path: <g>"a.b[0][0].c[0].d"</>
+
+Expected value: not <g>1</>
+`;
+
+exports[`.toHaveProperty() {pass: true} expect({"a": {"b": [{"c": [{"d": 1}]}]}}).toHaveProperty('a.b[0].c[0].d', 1) 1`] = `
+<d>expect(</><r>received</><d>).</>not<d>.</>toHaveProperty<d>(</><g>path</><d>, </><g>value</><d>)</>
+
+Expected path: <g>"a.b[0].c[0].d"</>
+
+Expected value: not <g>1</>
+`;
+
+exports[`.toHaveProperty() {pass: true} expect({"a": {"b": [{"c": {"d": [{"e": 1}, {"f": 2}]}}]}}).toHaveProperty('a.b[0].c.d[1].f', 2) 1`] = `
+<d>expect(</><r>received</><d>).</>not<d>.</>toHaveProperty<d>(</><g>path</><d>, </><g>value</><d>)</>
+
+Expected path: <g>"a.b[0].c.d[1].f"</>
+
+Expected value: not <g>2</>
+`;
+
 exports[`.toHaveProperty() {pass: true} expect({"a": {"b": [1, 2, 3]}}).toHaveProperty('a,b,1') 1`] = `
 <d>expect(</><r>received</><d>).</>not<d>.</>toHaveProperty<d>(</><g>path</><d>)</>
 

packages/expect/src/__tests__/matchers.test.js

@@ -1885,6 +1885,9 @@ describe('.toHaveProperty()', () => {
     [{a: {b: undefined}}, 'a.b', undefined],
     [{a: {}}, 'a.b', undefined], // delete for breaking change in future major
     [{a: {b: {c: 5}}}, 'a.b', {c: 5}],
+    [{a: {b: [{c: [{d: 1}]}]}}, 'a.b[0].c[0].d', 1],
+    [{a: {b: [{c: {d: [{e: 1}, {f: 2}]}}]}}, 'a.b[0].c.d[1].f', 2],
+    [{a: {b: [[{c: [{d: 1}]}]]}}, 'a.b[0][0].c[0].d', 1],
     [Object.assign(Object.create(null), {property: 1}), 'property', 1],
     [new Foo(), 'a', undefined],
     [new Foo(), 'b', 'b'],
@@ -1955,6 +1958,7 @@ describe('.toHaveProperty()', () => {
 
   [
     [{a: {b: {c: {}}}}, 'a.b.c.d'],
+    [{a: {b: {c: {}}}}, '.a.b.c'],
     [{a: 1}, 'a.b.c.d'],
     [{}, 'a'],
     [1, 'a.b.c'],

packages/expect/src/matchers.ts

@@ -44,6 +44,7 @@ import {
   getObjectSubset,
   getPath,
   iterableEquality,
+  pathAsArray,
   sparseArrayEquality,
   subsetEquality,
   typeEquality,
@@ -704,7 +705,7 @@ const matchers: MatchersObject = {
 
     const expectedPathLength =
       typeof expectedPath === 'string'
-        ? expectedPath.split('.').length
+        ? pathAsArray(expectedPath).length
         : expectedPath.length;
 
     if (expectedPathType === 'array' && expectedPathLength === 0) {

packages/expect/src/utils.ts

@@ -45,7 +45,7 @@ export const getPath = (
   propertyPath: string | Array<string>,
 ): GetPath => {
   if (!Array.isArray(propertyPath)) {
-    propertyPath = (propertyPath as string).split('.');
+    propertyPath = pathAsArray(propertyPath);
   }
 
   if (propertyPath.length) {
@@ -372,6 +372,24 @@ export const partition = <T>(
   return result;
 };
 
+export const pathAsArray = (propertyPath: string): Array<any> => {
+  // will match everything that's not a dot or a bracket, and "" for consecutive dots.
+  const pattern = RegExp('[^.[\\]]+|(?=(?:\\.)(?:\\.|$))', 'g');
+  const properties: Array<string> = [];
+
+  // Because the regex won't match a dot in the beginning of the path, if present.
+  if (propertyPath[0] === '.') {
+    properties.push('');
+  }
+
+  propertyPath.replace(pattern, match => {
+    properties.push(match);
+    return match;
+  });
+
+  return properties;
+};
+
 // Copied from https://github.com/graingert/angular.js/blob/a43574052e9775cbc1d7dd8a086752c979b0f020/src/Angular.js#L685-L693
 export const isError = (value: unknown): value is Error => {
   switch (Object.prototype.toString.call(value)) {