diff --git a/src/index.js b/src/index.js
index 45095f8961..1cfa91c1f9 100644
--- a/src/index.js
+++ b/src/index.js
@@ -174,6 +174,14 @@ export { default as nextWednesday } from './nextWednesday/index'
 export { default as parse } from './parse/index'
 export { default as parseISO } from './parseISO/index'
 export { default as parseJSON } from './parseJSON/index'
+export { default as previousDay } from './previousDay/index'
+export { default as previousMonday } from './previousMonday/index'
+export { default as previousTuesday } from './previousTuesday/index'
+export { default as previousWednesday } from './previousWednesday/index'
+export { default as previousThursday } from './previousThursday/index'
+export { default as previousFriday } from './previousFriday/index'
+export { default as previousSaturday } from './previousSaturday/index'
+export { default as previousSunday } from './previousSunday/index'
 export { default as quartersToMonths } from './quartersToMonths/index'
 export { default as quartersToYears } from './quartersToYears/index'
 export { default as roundToNearestMinutes } from './roundToNearestMinutes/index'
diff --git a/src/previousDay/index.ts b/src/previousDay/index.ts
new file mode 100644
index 0000000000..7440da6150
--- /dev/null
+++ b/src/previousDay/index.ts
@@ -0,0 +1,46 @@
+import requiredArgs from '../_lib/requiredArgs/index'
+import getDay from '../getDay'
+import subDays from '../subDays'
+import toDate from '../toDate'
+import { Day } from '../types'
+
+const baseMap = [1,2,3,4,5,6,7]
+
+/**
+ * @name previousDay
+ * @category Weekday Helpers
+ * @summary When is the previous day of the week?
+ *
+ * @description
+ * When is the previous day of the week? 0-6 the day of the week, 0 represents Sunday.
+ *
+ * @param {Date | number} date - the date to check
+ * @param {Day} day - day of the week
+ * @returns {Date} - the date is the previous day of week
+ * @throws {TypeError} - 2 arguments required
+ *
+ * @example
+ * // When is the previous Monday before Mar, 20, 2020?
+ * const result = previousDay(new Date(2020, 2, 20), 1)
+ * //=> Mon Mar 16 2020 00:00:00
+ *
+ * @example
+ * // When is the previous Tuesday before Mar, 21, 2020?
+ * const result = previousDay(new Date(2020, 2, 21), 2)
+ * //=> Tue Mar 17 2020 00:00:00
+ */
+export default function previousDay(date: Date | number, day: Day): Date {
+  requiredArgs(2, arguments)
+  const map = genMap(day+1)
+  return subDays(toDate(date), map[getDay(toDate(date))])
+}
+
+function genMap(daysToMove: number): number[] {
+  if (daysToMove === 0) {
+    return baseMap
+  } else {
+    const mapStart = baseMap.slice(-daysToMove)
+    const mapEnd = baseMap.slice(0, baseMap.length - daysToMove)
+    return mapStart.concat(mapEnd)
+  }
+}
diff --git a/src/previousDay/test.ts b/src/previousDay/test.ts
new file mode 100644
index 0000000000..1eb0680298
--- /dev/null
+++ b/src/previousDay/test.ts
@@ -0,0 +1,82 @@
+// @flow
+/* eslint-env mocha */
+
+import assert from 'power-assert'
+import previousDay from '.'
+
+describe('previousDay', function () {
+  it('returns the previous Monday given various dates after the same', function () {
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 18), 1),
+      new Date(2021, 5 /* Jun */, 14)
+    )
+
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 17), 1),
+      new Date(2021, 5 /* Jun */, 14)
+    )
+
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 14), 1),
+      new Date(2021, 5 /* Jun */, 7)
+    )
+
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 9), 1),
+      new Date(2021, 5 /* Jun */, 7)
+    )
+
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 8), 1),
+      new Date(2021, 5 /* Jun */, 7)
+    )
+
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 7), 1),
+      new Date(2021, 4 /* May */, 31)
+    )
+
+  })
+
+  it('returns the previous Tuesday given the Saturday after it', function () {
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 26), 2),
+      new Date(2020, 5 /* Jun */, 21)
+    )
+  })
+
+  it('returns the previous Wednesday given the Saturday after it', function () {
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 26), 3),
+      new Date(2021, 5 /* Jun */, 23)
+    )
+  })
+
+  it('returns the previous Thursday given the Saturday after it', function () {
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 26), 4),
+      new Date(2021, 5 /* Jun */, 24)
+    )
+  })
+
+  it('returns the previous Friday given the Saturday after it', function () {
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 26), 5),
+      new Date(2021, 5 /* Jun */, 25)
+    )
+  })
+
+  it('returns the previous Saturday given the Saturday after it', function () {
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 26), 6),
+      new Date(2021, 5 /* Jun */, 19)
+    )
+  })
+
+  it('returns previours Sunday given the day is Sunday', function () {
+    assert.deepStrictEqual(
+      previousDay(new Date(2021, 5 /* Jun */, 27), 0),
+      new Date(2021, 5 /* Jun */, 20)
+    )
+  })
+})
diff --git a/src/previousFriday/index.ts b/src/previousFriday/index.ts
new file mode 100644
index 0000000000..4e7b0288f3
--- /dev/null
+++ b/src/previousFriday/index.ts
@@ -0,0 +1,25 @@
+import requiredArgs from '../_lib/requiredArgs/index'
+import previousDay from '../previousDay/index'
+import toDate from '../toDate/index'
+
+/**
+ * @name previousFriday
+ * @category Weekday Helpers
+ * @summary When is the previous Friday?
+ *
+ * @description
+ * When is the previous Friday?
+ *
+ * @param {Date | number} date - the date to start counting from
+ * @returns {Date} the previous Friday
+ * @throws {TypeError} 1 argument required
+ *
+ * @example
+ * // When is the previous Friday before Jun, 19, 2021?
+ * const result = previousFriday(new Date(2021, 5, 19))
+ * //=> Fri June 18 2021 00:00:00
+ */
+export default function previousFriday(date: Date | number): Date {
+  requiredArgs(1, arguments)
+  return previousDay(toDate(date), 5)
+}
diff --git a/src/previousFriday/test.ts b/src/previousFriday/test.ts
new file mode 100644
index 0000000000..595db63e1d
--- /dev/null
+++ b/src/previousFriday/test.ts
@@ -0,0 +1,44 @@
+// @flow
+/* eslint-env mocha */
+
+import assert from 'power-assert'
+import previoursFriday from '.'
+
+describe('previoursFriday', function () {
+  it('returns the following Friday given various dates after the same', function () {
+    assert.deepStrictEqual(
+      previoursFriday(new Date(2021, 5 /* Jun */, 5)),
+      new Date(2021, 5 /* Jun */, 4)
+    )
+
+    assert.deepStrictEqual(
+      previoursFriday(new Date(2021, 5 /* Jun */, 6)),
+      new Date(2021, 5 /* Jun */, 4)
+    )
+
+    assert.deepStrictEqual(
+      previoursFriday(new Date(2021, 5 /* Jun */, 11)),
+      new Date(2021, 5 /* Jun */, 4)
+    )
+
+    assert.deepStrictEqual(
+      previoursFriday(new Date(2021, 5 /* Jun */, 14)),
+      new Date(2021, 5 /* Jun */, 11)
+    )
+
+    assert.deepStrictEqual(
+      previoursFriday(new Date(2021, 5 /* Jun */, 15)),
+      new Date(2021, 5 /* Jun */, 11)
+    )
+
+    assert.deepStrictEqual(
+      previoursFriday(new Date(2021, 5 /* Jun */, 24)),
+      new Date(2021, 5 /* Jun */, 18)
+    )
+
+  })
+
+  it('returns `Invalid Date` if the given date is invalid', function () {
+    assert(previoursFriday(new Date(NaN)) instanceof Date)
+  })
+})
diff --git a/src/previousMonday/index.ts b/src/previousMonday/index.ts
new file mode 100644
index 0000000000..ba9e43e3ee
--- /dev/null
+++ b/src/previousMonday/index.ts
@@ -0,0 +1,25 @@
+import requiredArgs from '../_lib/requiredArgs/index'
+import previousDay from '../previousDay/index'
+import toDate from '../toDate/index'
+
+/**
+ * @name previousMonday
+ * @category Weekday Helpers
+ * @summary When is the previous Monday?
+ *
+ * @description
+ * When is the previous Monday?
+ *
+ * @param {Date | number} date - the date to start counting from
+ * @returns {Date} the previous Monday
+ * @throws {TypeError} 1 argument required
+ *
+ * @example
+ * // When is the previous Monday before Jun, 18, 2021?
+ * const result = previousMonday(new Date(2021, 5, 18))
+ * //=> Mon June 14 2021 00:00:00
+ */
+export default function previousMonday(date: Date | number): Date {
+  requiredArgs(1, arguments)
+  return previousDay(toDate(date), 1)
+}
diff --git a/src/previousMonday/test.ts b/src/previousMonday/test.ts
new file mode 100644
index 0000000000..249d9bdcef
--- /dev/null
+++ b/src/previousMonday/test.ts
@@ -0,0 +1,44 @@
+// @flow
+/* eslint-env mocha */
+
+import assert from 'power-assert'
+import previoursMonday from '.'
+
+describe('previoursMonday', function () {
+  it('returns the following Monday given various dates after the same', function () {
+    assert.deepStrictEqual(
+      previoursMonday(new Date(2021, 5 /* Jun */, 5)),
+      new Date(2021, 4 /* May */, 31)
+    )
+
+    assert.deepStrictEqual(
+      previoursMonday(new Date(2021, 5 /* Jun */, 6)),
+      new Date(2021, 4 /* May */, 31)
+    )
+
+    assert.deepStrictEqual(
+      previoursMonday(new Date(2021, 5 /* Jun */, 7)),
+      new Date(2021, 4 /* May */, 31)
+    )
+
+    assert.deepStrictEqual(
+      previoursMonday(new Date(2021, 5 /* Jun */, 14)),
+      new Date(2021, 5 /* Jun */, 7)
+    )
+
+    assert.deepStrictEqual(
+      previoursMonday(new Date(2021, 5 /* Jun */, 15)),
+      new Date(2021, 5 /* Jun */, 14)
+    )
+
+    assert.deepStrictEqual(
+      previoursMonday(new Date(2021, 5 /* Jun */, 16)),
+      new Date(2021, 5 /* Jun */, 14)
+    )
+
+  })
+
+  it('returns `Invalid Date` if the given date is invalid', function () {
+    assert(previoursMonday(new Date(NaN)) instanceof Date)
+  })
+})
diff --git a/src/previousSaturday/index.ts b/src/previousSaturday/index.ts
new file mode 100644
index 0000000000..f3a529f44f
--- /dev/null
+++ b/src/previousSaturday/index.ts
@@ -0,0 +1,25 @@
+import requiredArgs from '../_lib/requiredArgs/index'
+import previousDay from '../previousDay/index'
+import toDate from '../toDate/index'
+
+/**
+ * @name previousSaturday
+ * @category Weekday Helpers
+ * @summary When is the previous Saturday?
+ *
+ * @description
+ * When is the previous Saturday?
+ *
+ * @param {Date | number} date - the date to start counting from
+ * @returns {Date} the previous Saturday
+ * @throws {TypeError} 1 argument required
+ *
+ * @example
+ * // When is the previous Saturday before Jun, 20, 2021?
+ * const result = previousSaturday(new Date(2021, 5, 20))
+ * //=> Fri June 19 2021 00:00:00
+ */
+export default function previousSaturday(date: Date | number): Date {
+  requiredArgs(1, arguments)
+  return previousDay(toDate(date), 6)
+}
diff --git a/src/previousSaturday/test.ts b/src/previousSaturday/test.ts
new file mode 100644
index 0000000000..c14c839f87
--- /dev/null
+++ b/src/previousSaturday/test.ts
@@ -0,0 +1,44 @@
+// @flow
+/* eslint-env mocha */
+
+import assert from 'power-assert'
+import previoursSaturday from '.'
+
+describe('previoursSaturday', function () {
+  it('returns the following Saturday given various dates after the same', function () {
+    assert.deepStrictEqual(
+      previoursSaturday(new Date(2021, 5 /* Jun */, 7)),
+      new Date(2021, 5 /* Jun */, 5)
+    )
+
+    assert.deepStrictEqual(
+      previoursSaturday(new Date(2021, 5 /* Jun */, 8)),
+      new Date(2021, 5 /* Jun */, 5)
+    )
+
+    assert.deepStrictEqual(
+      previoursSaturday(new Date(2021, 5 /* Jun */, 12)),
+      new Date(2021, 5 /* Jun */, 5)
+    )
+
+    assert.deepStrictEqual(
+      previoursSaturday(new Date(2021, 5 /* Jun */, 16)),
+      new Date(2021, 5 /* Jun */, 12)
+    )
+
+    assert.deepStrictEqual(
+      previoursSaturday(new Date(2021, 5 /* Jun */, 17)),
+      new Date(2021, 5 /* Jun */, 12)
+    )
+
+    assert.deepStrictEqual(
+      previoursSaturday(new Date(2021, 5 /* Jun */, 24)),
+      new Date(2021, 5 /* Jun */, 19)
+    )
+
+  })
+
+  it('returns `Invalid Date` if the given date is invalid', function () {
+    assert(previoursSaturday(new Date(NaN)) instanceof Date)
+  })
+})
diff --git a/src/previousSunday/index.ts b/src/previousSunday/index.ts
new file mode 100644
index 0000000000..375461287a
--- /dev/null
+++ b/src/previousSunday/index.ts
@@ -0,0 +1,25 @@
+import requiredArgs from '../_lib/requiredArgs/index'
+import previousDay from '../previousDay/index'
+import toDate from '../toDate/index'
+
+/**
+ * @name previousSunday
+ * @category Weekday Helpers
+ * @summary When is the previous Sunday?
+ *
+ * @description
+ * When is the previous Sunday?
+ *
+ * @param {Date | number} date - the date to start counting from
+ * @returns {Date} the previous Sunday
+ * @throws {TypeError} 1 argument required
+ *
+ * @example
+ * // When is the previous Sunday before Jun, 21, 2021?
+ * const result = previousSunday(new Date(2021, 5, 21))
+ * //=> Fri June 20 2021 00:00:00
+ */
+export default function previousSunday(date: Date | number): Date {
+  requiredArgs(1, arguments)
+  return previousDay(toDate(date), 0)
+}
diff --git a/src/previousSunday/test.ts b/src/previousSunday/test.ts
new file mode 100644
index 0000000000..b1eff92c97
--- /dev/null
+++ b/src/previousSunday/test.ts
@@ -0,0 +1,44 @@
+// @flow
+/* eslint-env mocha */
+
+import assert from 'power-assert'
+import previoursSunday from '.'
+
+describe('previoursSunday', function () {
+  it('returns the following Sunday given various dates after the same', function () {
+    assert.deepStrictEqual(
+      previoursSunday(new Date(2021, 5 /* Jun */, 7)),
+      new Date(2021, 5 /* Jun */, 6)
+    )
+
+    assert.deepStrictEqual(
+      previoursSunday(new Date(2021, 5 /* Jun */, 8)),
+      new Date(2021, 5 /* Jun */, 6)
+    )
+
+    assert.deepStrictEqual(
+      previoursSunday(new Date(2021, 5 /* Jun */, 13)),
+      new Date(2021, 5 /* Jun */, 6)
+    )
+
+    assert.deepStrictEqual(
+      previoursSunday(new Date(2021, 5 /* Jun */, 16)),
+      new Date(2021, 5 /* Jun */, 13)
+    )
+
+    assert.deepStrictEqual(
+      previoursSunday(new Date(2021, 5 /* Jun */, 17)),
+      new Date(2021, 5 /* Jun */, 13)
+    )
+
+    assert.deepStrictEqual(
+      previoursSunday(new Date(2021, 5 /* Jun */, 24)),
+      new Date(2021, 5 /* Jun */, 20)
+    )
+
+  })
+
+  it('returns `Invalid Date` if the given date is invalid', function () {
+    assert(previoursSunday(new Date(NaN)) instanceof Date)
+  })
+})
diff --git a/src/previousThursday/index.ts b/src/previousThursday/index.ts
new file mode 100644
index 0000000000..4c6c4909da
--- /dev/null
+++ b/src/previousThursday/index.ts
@@ -0,0 +1,25 @@
+import requiredArgs from '../_lib/requiredArgs/index'
+import previousDay from '../previousDay/index'
+import toDate from '../toDate/index'
+
+/**
+ * @name previousThursday
+ * @category Weekday Helpers
+ * @summary When is the previous Thursday?
+ *
+ * @description
+ * When is the previous Thursday?
+ *
+ * @param {Date | number} date - the date to start counting from
+ * @returns {Date} the previous Thursday
+ * @throws {TypeError} 1 argument required
+ *
+ * @example
+ * // When is the previous Thursday before Jun, 18, 2021?
+ * const result = previousThursday(new Date(2021, 5, 18))
+ * //=> Thu June 17 2021 00:00:00
+ */
+export default function previousThursday(date: Date | number): Date {
+  requiredArgs(1, arguments)
+  return previousDay(toDate(date), 4)
+}
diff --git a/src/previousThursday/test.ts b/src/previousThursday/test.ts
new file mode 100644
index 0000000000..3e3a011227
--- /dev/null
+++ b/src/previousThursday/test.ts
@@ -0,0 +1,44 @@
+// @flow
+/* eslint-env mocha */
+
+import assert from 'power-assert'
+import previoursThursday from '.'
+
+describe('previoursThursday', function () {
+  it('returns the following Thursday given various dates after the same', function () {
+    assert.deepStrictEqual(
+      previoursThursday(new Date(2021, 5 /* Jun */, 5)),
+      new Date(2021, 5 /* Jun */, 3)
+    )
+
+    assert.deepStrictEqual(
+      previoursThursday(new Date(2021, 5 /* Jun */, 6)),
+      new Date(2021, 5 /* Jun */, 3)
+    )
+
+    assert.deepStrictEqual(
+      previoursThursday(new Date(2021, 5 /* Jun */, 10)),
+      new Date(2021, 5 /* Jun */, 3)
+    )
+
+    assert.deepStrictEqual(
+      previoursThursday(new Date(2021, 5 /* Jun */, 14)),
+      new Date(2021, 5 /* Jun */, 10)
+    )
+
+    assert.deepStrictEqual(
+      previoursThursday(new Date(2021, 5 /* Jun */, 15)),
+      new Date(2021, 5 /* Jun */, 10)
+    )
+
+    assert.deepStrictEqual(
+      previoursThursday(new Date(2021, 5 /* Jun */, 24)),
+      new Date(2021, 5 /* Jun */, 17)
+    )
+
+  })
+
+  it('returns `Invalid Date` if the given date is invalid', function () {
+    assert(previoursThursday(new Date(NaN)) instanceof Date)
+  })
+})
diff --git a/src/previousTuesday/index.ts b/src/previousTuesday/index.ts
new file mode 100644
index 0000000000..af17bccac2
--- /dev/null
+++ b/src/previousTuesday/index.ts
@@ -0,0 +1,25 @@
+import requiredArgs from '../_lib/requiredArgs/index'
+import previousDay from '../previousDay/index'
+import toDate from '../toDate/index'
+
+/**
+ * @name previousTuesday
+ * @category Weekday Helpers
+ * @summary When is the previous Tuesday?
+ *
+ * @description
+ * When is the previous Tuesday?
+ *
+ * @param {Date | number} date - the date to start counting from
+ * @returns {Date} the previous Tuesday
+ * @throws {TypeError} 1 argument required
+ *
+ * @example
+ * // When is the previous Tuesday before Jun, 18, 2021?
+ * const result = previousTuesday(new Date(2021, 5, 18))
+ * //=> Tue June 15 2021 00:00:00
+ */
+export default function previousTuesday(date: Date | number): Date {
+  requiredArgs(1, arguments)
+  return previousDay(toDate(date), 2)
+}
\ No newline at end of file
diff --git a/src/previousTuesday/test.ts b/src/previousTuesday/test.ts
new file mode 100644
index 0000000000..62f51cfdc4
--- /dev/null
+++ b/src/previousTuesday/test.ts
@@ -0,0 +1,44 @@
+// @flow
+/* eslint-env mocha */
+
+import assert from 'power-assert'
+import previoursTuesday from '.'
+
+describe('previoursTuesday', function () {
+  it('returns the following Tuesday given various dates after the same', function () {
+    assert.deepStrictEqual(
+      previoursTuesday(new Date(2021, 5 /* Jun */, 5)),
+      new Date(2021, 5 /* Jun */, 1)
+    )
+
+    assert.deepStrictEqual(
+      previoursTuesday(new Date(2021, 5 /* Jun */, 6)),
+      new Date(2021, 5 /* Jun */, 1)
+    )
+
+    assert.deepStrictEqual(
+      previoursTuesday(new Date(2021, 5 /* Jun */, 8)),
+      new Date(2021, 5 /* Jun */, 1)
+    )
+
+    assert.deepStrictEqual(
+      previoursTuesday(new Date(2021, 5 /* Jun */, 15)),
+      new Date(2021, 5 /* Jun */, 8)
+    )
+
+    assert.deepStrictEqual(
+      previoursTuesday(new Date(2021, 5 /* Jun */, 17)),
+      new Date(2021, 5 /* Jun */, 15)
+    )
+
+    assert.deepStrictEqual(
+      previoursTuesday(new Date(2021, 5 /* Jun */, 18)),
+      new Date(2021, 5 /* Jun */, 15)
+    )
+
+  })
+
+  it('returns `Invalid Date` if the given date is invalid', function () {
+    assert(previoursTuesday(new Date(NaN)) instanceof Date)
+  })
+})
diff --git a/src/previousWednesday/index.ts b/src/previousWednesday/index.ts
new file mode 100644
index 0000000000..208603dc67
--- /dev/null
+++ b/src/previousWednesday/index.ts
@@ -0,0 +1,25 @@
+import requiredArgs from '../_lib/requiredArgs/index'
+import previousDay from '../previousDay/index'
+import toDate from '../toDate/index'
+
+/**
+ * @name previousWednesday
+ * @category Weekday Helpers
+ * @summary When is the previous Wednesday?
+ *
+ * @description
+ * When is the previous Wednesday?
+ *
+ * @param {Date | number} date - the date to start counting from
+ * @returns {Date} the previous Wednesday
+ * @throws {TypeError} 1 argument required
+ *
+ * @example
+ * // When is the previous Wednesday before Jun, 18, 2021?
+ * const result = previousWednesday(new Date(2021, 5, 18))
+ * //=> Wed June 16 2021 00:00:00
+ */
+export default function previousWednesday(date: Date | number): Date {
+  requiredArgs(1, arguments)
+  return previousDay(toDate(date), 3)
+}
diff --git a/src/previousWednesday/test.ts b/src/previousWednesday/test.ts
new file mode 100644
index 0000000000..1dd47c7d0a
--- /dev/null
+++ b/src/previousWednesday/test.ts
@@ -0,0 +1,44 @@
+// @flow
+/* eslint-env mocha */
+
+import assert from 'power-assert'
+import previoursWednesday from '.'
+
+describe('previoursWednesday', function () {
+  it('returns the following Wednesday given various dates after the same', function () {
+    assert.deepStrictEqual(
+      previoursWednesday(new Date(2021, 5 /* Jun */, 5)),
+      new Date(2021, 5 /* Jun */, 2)
+    )
+
+    assert.deepStrictEqual(
+      previoursWednesday(new Date(2021, 5 /* Jun */, 6)),
+      new Date(2021, 5 /* Jun */, 2)
+    )
+
+    assert.deepStrictEqual(
+      previoursWednesday(new Date(2021, 5 /* Jun */, 9)),
+      new Date(2021, 5 /* Jun */, 2)
+    )
+
+    assert.deepStrictEqual(
+      previoursWednesday(new Date(2021, 5 /* Jun */, 17)),
+      new Date(2021, 5 /* Jun */, 16)
+    )
+
+    assert.deepStrictEqual(
+      previoursWednesday(new Date(2021, 5 /* Jun */, 18)),
+      new Date(2021, 5 /* Jun */, 16)
+    )
+
+    assert.deepStrictEqual(
+      previoursWednesday(new Date(2021, 5 /* Jun */, 25)),
+      new Date(2021, 5 /* Jun */, 24)
+    )
+
+  })
+
+  it('returns `Invalid Date` if the given date is invalid', function () {
+    assert(previoursWednesday(new Date(NaN)) instanceof Date)
+  })
+})