Mail

frontend/node_modules/eslint-plugin-jest/docs/rules/prefer-to-contain.md

@@ -0,0 +1,45 @@
+# Suggest using `toContain()` (`prefer-to-contain`)
+
+In order to have a better failure message, `toContain()` should be used upon
+asserting expectations on an array containing an object.
+
+## Rule details
+
+This rule triggers a warning if `toBe()`, `toEqual()` or `toStrictEqual()` is
+used to assert object inclusion in an array
+
+```js
+expect(a.includes(b)).toBe(true);
+```
+
+```js
+expect(a.includes(b)).not.toBe(true);
+```
+
+```js
+expect(a.includes(b)).toBe(false);
+```
+
+### Default configuration
+
+The following patterns are considered warnings:
+
+```js
+expect(a.includes(b)).toBe(true);
+
+expect(a.includes(b)).not.toBe(true);
+
+expect(a.includes(b)).toBe(false);
+
+expect(a.includes(b)).toEqual(true);
+
+expect(a.includes(b)).toStrictEqual(true);
+```
+
+The following patterns are not considered warnings:
+
+```js
+expect(a).toContain(b);
+
+expect(a).not.toContain(b);
+```