From c5a100bfd08f4bea480ee334de968c8c81a56b25 Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Sun, 7 Aug 2022 18:30:35 -0400
Subject: [PATCH 01/16] feat: `datatype.hexadecimal` signature change

---
 src/modules/datatype/index.ts | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/src/modules/datatype/index.ts b/src/modules/datatype/index.ts
index 347013681b5..8bbbde43911 100644
--- a/src/modules/datatype/index.ts
+++ b/src/modules/datatype/index.ts
@@ -187,13 +187,18 @@ export class Datatype {
   /**
    * Returns a [hexadecimal](https://en.wikipedia.org/wiki/Hexadecimal) number.
    *
-   * @param length Length of the generated number. Defaults to `1`.
+   * @param options The optional options object.
+   * @param options.length Length of the generated number. Defaults to `1`.
+   * @param options.prefix Prefix for the generated number. Defaults to `''`.
    *
    * @example
    * faker.datatype.hexadecimal() // '0xb'
    * faker.datatype.hexadecimal(10) // '0xaE13F044fb'
    */
-  hexadecimal(length = 1): string {
+  hexadecimal(options?: { length?: number; prefix?: string }): string {
+    const length = options?.length ?? 1;
+    const prefix = options?.prefix ?? '';
+
     let wholeString = '';
 
     for (let i = 0; i < length; i++) {
@@ -223,7 +228,7 @@ export class Datatype {
       ]);
     }
 
-    return `0x${wholeString}`;
+    return `${prefix}${wholeString}`;
   }
 
   /**

From 92129229dfbff3168a6c49461f20e8b919b131af Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Sun, 7 Aug 2022 19:11:57 -0400
Subject: [PATCH 02/16] chore: update hex func examples with new params

---
 src/modules/datatype/index.ts | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/modules/datatype/index.ts b/src/modules/datatype/index.ts
index 8bbbde43911..6bb62268041 100644
--- a/src/modules/datatype/index.ts
+++ b/src/modules/datatype/index.ts
@@ -192,8 +192,10 @@ export class Datatype {
    * @param options.prefix Prefix for the generated number. Defaults to `''`.
    *
    * @example
-   * faker.datatype.hexadecimal() // '0xb'
-   * faker.datatype.hexadecimal(10) // '0xaE13F044fb'
+   * faker.datatype.hexadecimal() // 'b'
+   * faker.datatype.hexadecimal({ length: 10 }) // 'aE13F044fb'
+   * faker.datatype.hexadecimal({ prefix: '0x' }) // '0xE'
+   * faker.datatype.hexadecimal({ length: 10, prefix: '0x' }) // '0xz12a974fb1'
    */
   hexadecimal(options?: { length?: number; prefix?: string }): string {
     const length = options?.length ?? 1;

From 4626e4391cc43ea1e5e5a73581569d3c4e53e4c8 Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Sun, 7 Aug 2022 19:13:26 -0400
Subject: [PATCH 03/16] chore: update `datatype.hexadecimal` func calls

---
 src/modules/color/index.ts    |  4 +++-
 src/modules/database/index.ts |  3 +--
 src/modules/finance/index.ts  |  4 +++-
 test/datatype.spec.ts         | 12 ++++++------
 4 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/src/modules/color/index.ts b/src/modules/color/index.ts
index 8b5fdba277c..921edaac5e5 100644
--- a/src/modules/color/index.ts
+++ b/src/modules/color/index.ts
@@ -297,7 +297,9 @@ export class Color {
     let color: string | number[];
     let cssFunction: CSSFunction = 'rgb';
     if (format === 'hex') {
-      color = this.faker.datatype.hexadecimal(includeAlpha ? 8 : 6).slice(2);
+      color = this.faker.datatype
+        .hexadecimal({ length: includeAlpha ? 8 : 6, prefix })
+        .slice(prefix.length);
       color = formatHexColor(color, options);
       return color;
     }
diff --git a/src/modules/database/index.ts b/src/modules/database/index.ts
index 073d3f8a1dd..b887cc610e4 100644
--- a/src/modules/database/index.ts
+++ b/src/modules/database/index.ts
@@ -69,7 +69,6 @@ export class Database {
    * faker.database.mongodbObjectId() // 'e175cac316a79afdd0ad3afb'
    */
   mongodbObjectId(): string {
-    // strip the "0x" from the hexadecimal output
-    return this.faker.datatype.hexadecimal(24).replace('0x', '').toLowerCase();
+    return this.faker.datatype.hexadecimal({ length: 24 }).toLowerCase();
   }
 }
diff --git a/src/modules/finance/index.ts b/src/modules/finance/index.ts
index 7085ea3654c..02f20f624e9 100644
--- a/src/modules/finance/index.ts
+++ b/src/modules/finance/index.ts
@@ -321,7 +321,9 @@ export class Finance {
    * faker.finance.ethereumAddress() // '0xf03dfeecbafc5147241cc4c4ca20b3c9dfd04c4a'
    */
   ethereumAddress(): string {
-    const address = this.faker.datatype.hexadecimal(40).toLowerCase();
+    const address = this.faker.datatype
+      .hexadecimal({ length: 40, prefix: '0x' })
+      .toLowerCase();
     return address;
   }
 
diff --git a/test/datatype.spec.ts b/test/datatype.spec.ts
index 56d4ea17f27..0de756b5465 100644
--- a/test/datatype.spec.ts
+++ b/test/datatype.spec.ts
@@ -59,7 +59,7 @@ describe('datatype', () => {
     t.itRepeated('boolean', 5);
 
     t.describe('hexadecimal', (t) => {
-      t.it('noArgs').it('with length', 42);
+      t.it('noArgs').it('with length', { length: 42 });
     });
 
     t.it('json');
@@ -323,14 +323,14 @@ describe('datatype', () => {
       describe('hexadecimal', () => {
         it('generates single hex character when no additional argument was provided', () => {
           const hex = faker.datatype.hexadecimal();
-          expect(hex).toMatch(/^(0x)[0-9a-f]{1}$/i);
-          expect(hex.substring(2)).toHaveLength(1);
+          expect(hex).toMatch(/^[0-9a-f]{1}$/i);
+          expect(hex).toHaveLength(1);
         });
 
         it('generates a random hex string', () => {
-          const hex = faker.datatype.hexadecimal(5);
-          expect(hex).toMatch(/^(0x)[0-9a-f]+$/i);
-          expect(hex.substring(2)).toHaveLength(5);
+          const hex = faker.datatype.hexadecimal({ length: 5 });
+          expect(hex).toMatch(/^[0-9a-f]+$/i);
+          expect(hex).toHaveLength(5);
         });
       });
 

From bf26ea703218dc5214997f81a05744c91f0651f1 Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Sun, 7 Aug 2022 19:14:21 -0400
Subject: [PATCH 04/16] test: update existing hexadecimal snapshot tests

---
 test/__snapshots__/datatype.spec.ts.snap | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/test/__snapshots__/datatype.spec.ts.snap b/test/__snapshots__/datatype.spec.ts.snap
index e7b8e414320..6a722c60011 100644
--- a/test/__snapshots__/datatype.spec.ts.snap
+++ b/test/__snapshots__/datatype.spec.ts.snap
@@ -70,9 +70,9 @@ exports[`datatype > 42 > float > with min and max 1`] = `-0.43`;
 
 exports[`datatype > 42 > float > with min, max and precision 1`] = `-0.4261`;
 
-exports[`datatype > 42 > hexadecimal > noArgs 1`] = `"0x8"`;
+exports[`datatype > 42 > hexadecimal > noArgs 1`] = `"8"`;
 
-exports[`datatype > 42 > hexadecimal > with length 1`] = `"0x8BE4ABdd39321aD7d3fe01FfCE404F4d6db0906bd8"`;
+exports[`datatype > 42 > hexadecimal > with length 1`] = `"8BE4ABdd39321aD7d3fe01FfCE404F4d6db0906bd8"`;
 
 exports[`datatype > 42 > json 1`] = `"{\\"foo\\":79654,\\"bar\\":\\"2eiXX/J/*&\\",\\"bike\\":86617,\\"a\\":60111,\\"b\\":70807,\\"name\\":\\"\\\\\\"&{dnx4!1}\\",\\"prop\\":61748}"`;
 
@@ -180,9 +180,9 @@ exports[`datatype > 1211 > float > with min and max 1`] = `61.07`;
 
 exports[`datatype > 1211 > float > with min, max and precision 1`] = `61.0658`;
 
-exports[`datatype > 1211 > hexadecimal > noArgs 1`] = `"0xE"`;
+exports[`datatype > 1211 > hexadecimal > noArgs 1`] = `"E"`;
 
-exports[`datatype > 1211 > hexadecimal > with length 1`] = `"0xEaDB42F0e3f4A973fAB0AeefCE96DFCF49cD438dF9"`;
+exports[`datatype > 1211 > hexadecimal > with length 1`] = `"EaDB42F0e3f4A973fAB0AeefCE96DFCF49cD438dF9"`;
 
 exports[`datatype > 1211 > json 1`] = `"{\\"foo\\":\\"Kti5-}$_/\`\\",\\"bar\\":76408,\\"bike\\":35403,\\"a\\":69406,\\"b\\":\\"l\\\\\\"h^]dnwI<\\",\\"name\\":\\"|p|5KWu3/C\\",\\"prop\\":\\"|Jh!E=x\\\\\\"RH\\"}"`;
 
@@ -290,9 +290,9 @@ exports[`datatype > 1337 > float > with min and max 1`] = `-12.92`;
 
 exports[`datatype > 1337 > float > with min, max and precision 1`] = `-12.9153`;
 
-exports[`datatype > 1337 > hexadecimal > noArgs 1`] = `"0x5"`;
+exports[`datatype > 1337 > hexadecimal > noArgs 1`] = `"5"`;
 
-exports[`datatype > 1337 > hexadecimal > with length 1`] = `"0x5c346ba075bd57F5A62B82d72AF39CBBB07a98cbA8"`;
+exports[`datatype > 1337 > hexadecimal > with length 1`] = `"5c346ba075bd57F5A62B82d72AF39CBBB07a98cbA8"`;
 
 exports[`datatype > 1337 > json 1`] = `"{\\"foo\\":56052,\\"bar\\":21258,\\"bike\\":54308,\\"a\\":3397,\\"b\\":23538,\\"name\\":\\"X9@{:e=+kD\\",\\"prop\\":62850}"`;
 

From e910c4e720f868a51cec3c87fe646ee7ec74e578 Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Sun, 7 Aug 2022 19:19:38 -0400
Subject: [PATCH 05/16] test: add seeded tests for new params

---
 test/__snapshots__/datatype.spec.ts.snap | 12 ++++++++++++
 test/datatype.spec.ts                    |  5 ++++-
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/test/__snapshots__/datatype.spec.ts.snap b/test/__snapshots__/datatype.spec.ts.snap
index 6a722c60011..10f5d4b081c 100644
--- a/test/__snapshots__/datatype.spec.ts.snap
+++ b/test/__snapshots__/datatype.spec.ts.snap
@@ -74,6 +74,10 @@ exports[`datatype > 42 > hexadecimal > noArgs 1`] = `"8"`;
 
 exports[`datatype > 42 > hexadecimal > with length 1`] = `"8BE4ABdd39321aD7d3fe01FfCE404F4d6db0906bd8"`;
 
+exports[`datatype > 42 > hexadecimal > with length and prefix 1`] = `"0x8BE4ABdd39321aD7d3fe"`;
+
+exports[`datatype > 42 > hexadecimal > with prefix 1`] = `"0x8"`;
+
 exports[`datatype > 42 > json 1`] = `"{\\"foo\\":79654,\\"bar\\":\\"2eiXX/J/*&\\",\\"bike\\":86617,\\"a\\":60111,\\"b\\":70807,\\"name\\":\\"\\\\\\"&{dnx4!1}\\",\\"prop\\":61748}"`;
 
 exports[`datatype > 42 > number > noArgs 1`] = `37454`;
@@ -184,6 +188,10 @@ exports[`datatype > 1211 > hexadecimal > noArgs 1`] = `"E"`;
 
 exports[`datatype > 1211 > hexadecimal > with length 1`] = `"EaDB42F0e3f4A973fAB0AeefCE96DFCF49cD438dF9"`;
 
+exports[`datatype > 1211 > hexadecimal > with length and prefix 1`] = `"0xEaDB42F0e3f4A973fAB0"`;
+
+exports[`datatype > 1211 > hexadecimal > with prefix 1`] = `"0xE"`;
+
 exports[`datatype > 1211 > json 1`] = `"{\\"foo\\":\\"Kti5-}$_/\`\\",\\"bar\\":76408,\\"bike\\":35403,\\"a\\":69406,\\"b\\":\\"l\\\\\\"h^]dnwI<\\",\\"name\\":\\"|p|5KWu3/C\\",\\"prop\\":\\"|Jh!E=x\\\\\\"RH\\"}"`;
 
 exports[`datatype > 1211 > number > noArgs 1`] = `92852`;
@@ -294,6 +302,10 @@ exports[`datatype > 1337 > hexadecimal > noArgs 1`] = `"5"`;
 
 exports[`datatype > 1337 > hexadecimal > with length 1`] = `"5c346ba075bd57F5A62B82d72AF39CBBB07a98cbA8"`;
 
+exports[`datatype > 1337 > hexadecimal > with length and prefix 1`] = `"0x5c346ba075bd57F5A62B"`;
+
+exports[`datatype > 1337 > hexadecimal > with prefix 1`] = `"0x5"`;
+
 exports[`datatype > 1337 > json 1`] = `"{\\"foo\\":56052,\\"bar\\":21258,\\"bike\\":54308,\\"a\\":3397,\\"b\\":23538,\\"name\\":\\"X9@{:e=+kD\\",\\"prop\\":62850}"`;
 
 exports[`datatype > 1337 > number > noArgs 1`] = `26202`;
diff --git a/test/datatype.spec.ts b/test/datatype.spec.ts
index 0de756b5465..4bceb06f595 100644
--- a/test/datatype.spec.ts
+++ b/test/datatype.spec.ts
@@ -59,7 +59,10 @@ describe('datatype', () => {
     t.itRepeated('boolean', 5);
 
     t.describe('hexadecimal', (t) => {
-      t.it('noArgs').it('with length', { length: 42 });
+      t.it('noArgs')
+        .it('with length', { length: 42 })
+        .it('with prefix', { prefix: '0x' })
+        .it('with length and prefix', { length: 20, prefix: '0x' });
     });
 
     t.it('json');

From ff400539734c5de2f97cf5e71ec4fda8097eba1b Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Sun, 7 Aug 2022 19:32:30 -0400
Subject: [PATCH 06/16] test: add unseeded tests for new params

---
 test/datatype.spec.ts | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/test/datatype.spec.ts b/test/datatype.spec.ts
index 4bceb06f595..298bc9760f0 100644
--- a/test/datatype.spec.ts
+++ b/test/datatype.spec.ts
@@ -330,11 +330,26 @@ describe('datatype', () => {
           expect(hex).toHaveLength(1);
         });
 
-        it('generates a random hex string', () => {
+        it('generates a random hex string with a provided length', () => {
           const hex = faker.datatype.hexadecimal({ length: 5 });
           expect(hex).toMatch(/^[0-9a-f]+$/i);
           expect(hex).toHaveLength(5);
         });
+
+        it('generates a hex string with a provided prefix', () => {
+          const hex = faker.datatype.hexadecimal({ prefix: '0x' });
+          expect(hex).toMatch(/^(0x)[0-9a-f]+$/i);
+          expect(hex).toHaveLength(3);
+        });
+
+        it('generates a hex string with a provided prefix and length', () => {
+          const hex = faker.datatype.hexadecimal({
+            prefix: '0x',
+            length: 7,
+          });
+          expect(hex).toMatch(/^(0x)[0-9a-f]+$/i);
+          expect(hex.substring(2)).toHaveLength(7);
+        });
       });
 
       describe('json', () => {

From 7894387bb773e86286b1d93c18dd754864218ef6 Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Mon, 8 Aug 2022 12:35:58 -0400
Subject: [PATCH 07/16] chore: rewrite func sig using deprecation workflow

This should no longer be a breaking change.
---
 src/modules/datatype/index.ts | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/modules/datatype/index.ts b/src/modules/datatype/index.ts
index 6bb62268041..315f6937cfe 100644
--- a/src/modules/datatype/index.ts
+++ b/src/modules/datatype/index.ts
@@ -1,5 +1,6 @@
 import type { Faker } from '../..';
 import { FakerError } from '../../errors/faker-error';
+import { deprecated } from '../../internal/deprecated';
 
 /**
  * Module to generate various primitive values and data types.
@@ -197,7 +198,19 @@ export class Datatype {
    * faker.datatype.hexadecimal({ prefix: '0x' }) // '0xE'
    * faker.datatype.hexadecimal({ length: 10, prefix: '0x' }) // '0xz12a974fb1'
    */
-  hexadecimal(options?: { length?: number; prefix?: string }): string {
+  hexadecimal(options?: { length?: number; prefix?: string } | number): string {
+    if (typeof options === 'number') {
+      deprecated({
+        deprecated: 'faker.datatype.hexadecimal(length)',
+        proposed: 'faker.datatype.hexadecimal({ length })',
+        since: '7.4',
+        until: '8.0',
+      });
+      options = {
+        length: options,
+      };
+    }
+
     const length = options?.length ?? 1;
     const prefix = options?.prefix ?? '';
 

From f93d6372a170cc970e600d96b7589538f442da3b Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Mon, 8 Aug 2022 12:55:05 -0400
Subject: [PATCH 08/16] feat: add `case` option

---
 src/modules/database/index.ts |  2 +-
 src/modules/datatype/index.ts | 22 +++++++++++++++++-----
 src/modules/finance/index.ts  |  8 +++++---
 3 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/src/modules/database/index.ts b/src/modules/database/index.ts
index b887cc610e4..5887ab097e5 100644
--- a/src/modules/database/index.ts
+++ b/src/modules/database/index.ts
@@ -69,6 +69,6 @@ export class Database {
    * faker.database.mongodbObjectId() // 'e175cac316a79afdd0ad3afb'
    */
   mongodbObjectId(): string {
-    return this.faker.datatype.hexadecimal({ length: 24 }).toLowerCase();
+    return this.faker.datatype.hexadecimal({ length: 24, case: 'lower' });
   }
 }
diff --git a/src/modules/datatype/index.ts b/src/modules/datatype/index.ts
index 315f6937cfe..a0d1091eb17 100644
--- a/src/modules/datatype/index.ts
+++ b/src/modules/datatype/index.ts
@@ -191,14 +191,23 @@ export class Datatype {
    * @param options The optional options object.
    * @param options.length Length of the generated number. Defaults to `1`.
    * @param options.prefix Prefix for the generated number. Defaults to `''`.
+   * @param options.case Case of the generated number. Defaults to `'upper'`.
    *
    * @example
-   * faker.datatype.hexadecimal() // 'b'
-   * faker.datatype.hexadecimal({ length: 10 }) // 'aE13F044fb'
+   * faker.datatype.hexadecimal() // 'B'
+   * faker.datatype.hexadecimal({ length: 10 }) // 'AE13F044FB'
    * faker.datatype.hexadecimal({ prefix: '0x' }) // '0xE'
-   * faker.datatype.hexadecimal({ length: 10, prefix: '0x' }) // '0xz12a974fb1'
+   * faker.datatype.hexadecimal({ case: 'lower' }) // 'f'
+   * faker.datatype.hexadecimal({ length: 10, prefix: '0x' }) // '0F12A974FB1'
+   * faker.datatype.hexadecimal({ length: 10, case: 'lower' }) // 'eef38014fb'
+   * faker.datatype.hexadecimal({ prefix: '0x', case: 'lower' }) // '0xd'
+   * faker.datatype.hexadecimal({ length: 10, prefix: '0x', case: 'lower' }) // '0xfdc330a4b1'
    */
-  hexadecimal(options?: { length?: number; prefix?: string } | number): string {
+  hexadecimal(
+    options?:
+      | { length?: number; prefix?: string; case?: 'lower' | 'upper' }
+      | number
+  ): string {
     if (typeof options === 'number') {
       deprecated({
         deprecated: 'faker.datatype.hexadecimal(length)',
@@ -213,6 +222,7 @@ export class Datatype {
 
     const length = options?.length ?? 1;
     const prefix = options?.prefix ?? '';
+    const letterCase = options?.case ?? 'upper';
 
     let wholeString = '';
 
@@ -243,7 +253,9 @@ export class Datatype {
       ]);
     }
 
-    return `${prefix}${wholeString}`;
+    return letterCase === 'upper'
+      ? `${prefix}${wholeString}`.toUpperCase()
+      : `${prefix}${wholeString}`.toLowerCase();
   }
 
   /**
diff --git a/src/modules/finance/index.ts b/src/modules/finance/index.ts
index 02f20f624e9..f1b089e320c 100644
--- a/src/modules/finance/index.ts
+++ b/src/modules/finance/index.ts
@@ -321,9 +321,11 @@ export class Finance {
    * faker.finance.ethereumAddress() // '0xf03dfeecbafc5147241cc4c4ca20b3c9dfd04c4a'
    */
   ethereumAddress(): string {
-    const address = this.faker.datatype
-      .hexadecimal({ length: 40, prefix: '0x' })
-      .toLowerCase();
+    const address = this.faker.datatype.hexadecimal({
+      length: 40,
+      prefix: '0x',
+      case: 'lower',
+    });
     return address;
   }
 

From ef0b385105f9552d349b1131299b47a11cb57104 Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Mon, 8 Aug 2022 13:01:49 -0400
Subject: [PATCH 09/16] test: update hexadecimal tests for new param

---
 test/__snapshots__/datatype.spec.ts.snap | 24 +++++++++++++++---------
 test/datatype.spec.ts                    | 12 ++++++++++--
 2 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/test/__snapshots__/datatype.spec.ts.snap b/test/__snapshots__/datatype.spec.ts.snap
index 10f5d4b081c..fbf2f1bdc18 100644
--- a/test/__snapshots__/datatype.spec.ts.snap
+++ b/test/__snapshots__/datatype.spec.ts.snap
@@ -72,11 +72,13 @@ exports[`datatype > 42 > float > with min, max and precision 1`] = `-0.4261`;
 
 exports[`datatype > 42 > hexadecimal > noArgs 1`] = `"8"`;
 
-exports[`datatype > 42 > hexadecimal > with length 1`] = `"8BE4ABdd39321aD7d3fe01FfCE404F4d6db0906bd8"`;
+exports[`datatype > 42 > hexadecimal > with casing 1`] = `"8"`;
 
-exports[`datatype > 42 > hexadecimal > with length and prefix 1`] = `"0x8BE4ABdd39321aD7d3fe"`;
+exports[`datatype > 42 > hexadecimal > with length 1`] = `"8BE4ABDD39321AD7D3FE01FFCE404F4D6DB0906BD8"`;
 
-exports[`datatype > 42 > hexadecimal > with prefix 1`] = `"0x8"`;
+exports[`datatype > 42 > hexadecimal > with length and prefix 1`] = `"0X8BE4ABDD39321AD7D3FE"`;
+
+exports[`datatype > 42 > hexadecimal > with prefix 1`] = `"0X8"`;
 
 exports[`datatype > 42 > json 1`] = `"{\\"foo\\":79654,\\"bar\\":\\"2eiXX/J/*&\\",\\"bike\\":86617,\\"a\\":60111,\\"b\\":70807,\\"name\\":\\"\\\\\\"&{dnx4!1}\\",\\"prop\\":61748}"`;
 
@@ -186,11 +188,13 @@ exports[`datatype > 1211 > float > with min, max and precision 1`] = `61.0658`;
 
 exports[`datatype > 1211 > hexadecimal > noArgs 1`] = `"E"`;
 
-exports[`datatype > 1211 > hexadecimal > with length 1`] = `"EaDB42F0e3f4A973fAB0AeefCE96DFCF49cD438dF9"`;
+exports[`datatype > 1211 > hexadecimal > with casing 1`] = `"e"`;
+
+exports[`datatype > 1211 > hexadecimal > with length 1`] = `"EADB42F0E3F4A973FAB0AEEFCE96DFCF49CD438DF9"`;
 
-exports[`datatype > 1211 > hexadecimal > with length and prefix 1`] = `"0xEaDB42F0e3f4A973fAB0"`;
+exports[`datatype > 1211 > hexadecimal > with length and prefix 1`] = `"0XEADB42F0E3F4A973FAB0"`;
 
-exports[`datatype > 1211 > hexadecimal > with prefix 1`] = `"0xE"`;
+exports[`datatype > 1211 > hexadecimal > with prefix 1`] = `"0XE"`;
 
 exports[`datatype > 1211 > json 1`] = `"{\\"foo\\":\\"Kti5-}$_/\`\\",\\"bar\\":76408,\\"bike\\":35403,\\"a\\":69406,\\"b\\":\\"l\\\\\\"h^]dnwI<\\",\\"name\\":\\"|p|5KWu3/C\\",\\"prop\\":\\"|Jh!E=x\\\\\\"RH\\"}"`;
 
@@ -300,11 +304,13 @@ exports[`datatype > 1337 > float > with min, max and precision 1`] = `-12.9153`;
 
 exports[`datatype > 1337 > hexadecimal > noArgs 1`] = `"5"`;
 
-exports[`datatype > 1337 > hexadecimal > with length 1`] = `"5c346ba075bd57F5A62B82d72AF39CBBB07a98cbA8"`;
+exports[`datatype > 1337 > hexadecimal > with casing 1`] = `"5"`;
+
+exports[`datatype > 1337 > hexadecimal > with length 1`] = `"5C346BA075BD57F5A62B82D72AF39CBBB07A98CBA8"`;
 
-exports[`datatype > 1337 > hexadecimal > with length and prefix 1`] = `"0x5c346ba075bd57F5A62B"`;
+exports[`datatype > 1337 > hexadecimal > with length and prefix 1`] = `"0X5C346BA075BD57F5A62B"`;
 
-exports[`datatype > 1337 > hexadecimal > with prefix 1`] = `"0x5"`;
+exports[`datatype > 1337 > hexadecimal > with prefix 1`] = `"0X5"`;
 
 exports[`datatype > 1337 > json 1`] = `"{\\"foo\\":56052,\\"bar\\":21258,\\"bike\\":54308,\\"a\\":3397,\\"b\\":23538,\\"name\\":\\"X9@{:e=+kD\\",\\"prop\\":62850}"`;
 
diff --git a/test/datatype.spec.ts b/test/datatype.spec.ts
index 298bc9760f0..dfbc105af5b 100644
--- a/test/datatype.spec.ts
+++ b/test/datatype.spec.ts
@@ -62,6 +62,7 @@ describe('datatype', () => {
       t.it('noArgs')
         .it('with length', { length: 42 })
         .it('with prefix', { prefix: '0x' })
+        .it('with casing', { case: 'lower' })
         .it('with length and prefix', { length: 20, prefix: '0x' });
     });
 
@@ -338,14 +339,21 @@ describe('datatype', () => {
 
         it('generates a hex string with a provided prefix', () => {
           const hex = faker.datatype.hexadecimal({ prefix: '0x' });
-          expect(hex).toMatch(/^(0x)[0-9a-f]+$/i);
+          expect(hex).toMatch(/^(0x)[0-9A-F]+$/i);
           expect(hex).toHaveLength(3);
         });
 
-        it('generates a hex string with a provided prefix and length', () => {
+        it('generates a hex string with a provided casing', () => {
+          const hex = faker.datatype.hexadecimal({ case: 'lower' });
+          expect(hex).toMatch(/^[0-9a-f]+$/i);
+          expect(hex).toHaveLength(1);
+        });
+
+        it('generates a hex string with a provided prefix, length, and casing', () => {
           const hex = faker.datatype.hexadecimal({
             prefix: '0x',
             length: 7,
+            case: 'lower',
           });
           expect(hex).toMatch(/^(0x)[0-9a-f]+$/i);
           expect(hex.substring(2)).toHaveLength(7);

From a030ff39e69a533955dbc332bf0f3a2ce326e0bb Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Mon, 8 Aug 2022 13:09:07 -0400
Subject: [PATCH 10/16] fix: only cast actual number to lowercase, not prefix

---
 src/modules/datatype/index.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/modules/datatype/index.ts b/src/modules/datatype/index.ts
index a0d1091eb17..750313f36a2 100644
--- a/src/modules/datatype/index.ts
+++ b/src/modules/datatype/index.ts
@@ -254,8 +254,8 @@ export class Datatype {
     }
 
     return letterCase === 'upper'
-      ? `${prefix}${wholeString}`.toUpperCase()
-      : `${prefix}${wholeString}`.toLowerCase();
+      ? `${prefix}${wholeString.toUpperCase()}`
+      : `${prefix}${wholeString.toLowerCase()}`;
   }
 
   /**

From 0b177fef4d99064c4550eca22bb74f93b02c8d4f Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Mon, 8 Aug 2022 13:15:08 -0400
Subject: [PATCH 11/16] test: update seeded tests with new param

---
 test/__snapshots__/datatype.spec.ts.snap | 18 ++++++++++++------
 test/datatype.spec.ts                    |  6 +++++-
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/test/__snapshots__/datatype.spec.ts.snap b/test/__snapshots__/datatype.spec.ts.snap
index fbf2f1bdc18..b527e10fdf6 100644
--- a/test/__snapshots__/datatype.spec.ts.snap
+++ b/test/__snapshots__/datatype.spec.ts.snap
@@ -76,9 +76,11 @@ exports[`datatype > 42 > hexadecimal > with casing 1`] = `"8"`;
 
 exports[`datatype > 42 > hexadecimal > with length 1`] = `"8BE4ABDD39321AD7D3FE01FFCE404F4D6DB0906BD8"`;
 
-exports[`datatype > 42 > hexadecimal > with length and prefix 1`] = `"0X8BE4ABDD39321AD7D3FE"`;
+exports[`datatype > 42 > hexadecimal > with length and prefix 1`] = `"0x8BE4ABDD39321AD7D3FE"`;
 
-exports[`datatype > 42 > hexadecimal > with prefix 1`] = `"0X8"`;
+exports[`datatype > 42 > hexadecimal > with length, prefix, and casing 1`] = `"0x8be4abdd39321ad7d3fe"`;
+
+exports[`datatype > 42 > hexadecimal > with prefix 1`] = `"0x8"`;
 
 exports[`datatype > 42 > json 1`] = `"{\\"foo\\":79654,\\"bar\\":\\"2eiXX/J/*&\\",\\"bike\\":86617,\\"a\\":60111,\\"b\\":70807,\\"name\\":\\"\\\\\\"&{dnx4!1}\\",\\"prop\\":61748}"`;
 
@@ -192,9 +194,11 @@ exports[`datatype > 1211 > hexadecimal > with casing 1`] = `"e"`;
 
 exports[`datatype > 1211 > hexadecimal > with length 1`] = `"EADB42F0E3F4A973FAB0AEEFCE96DFCF49CD438DF9"`;
 
-exports[`datatype > 1211 > hexadecimal > with length and prefix 1`] = `"0XEADB42F0E3F4A973FAB0"`;
+exports[`datatype > 1211 > hexadecimal > with length and prefix 1`] = `"0xEADB42F0E3F4A973FAB0"`;
+
+exports[`datatype > 1211 > hexadecimal > with length, prefix, and casing 1`] = `"0xeadb42f0e3f4a973fab0"`;
 
-exports[`datatype > 1211 > hexadecimal > with prefix 1`] = `"0XE"`;
+exports[`datatype > 1211 > hexadecimal > with prefix 1`] = `"0xE"`;
 
 exports[`datatype > 1211 > json 1`] = `"{\\"foo\\":\\"Kti5-}$_/\`\\",\\"bar\\":76408,\\"bike\\":35403,\\"a\\":69406,\\"b\\":\\"l\\\\\\"h^]dnwI<\\",\\"name\\":\\"|p|5KWu3/C\\",\\"prop\\":\\"|Jh!E=x\\\\\\"RH\\"}"`;
 
@@ -308,9 +312,11 @@ exports[`datatype > 1337 > hexadecimal > with casing 1`] = `"5"`;
 
 exports[`datatype > 1337 > hexadecimal > with length 1`] = `"5C346BA075BD57F5A62B82D72AF39CBBB07A98CBA8"`;
 
-exports[`datatype > 1337 > hexadecimal > with length and prefix 1`] = `"0X5C346BA075BD57F5A62B"`;
+exports[`datatype > 1337 > hexadecimal > with length and prefix 1`] = `"0x5C346BA075BD57F5A62B"`;
+
+exports[`datatype > 1337 > hexadecimal > with length, prefix, and casing 1`] = `"0x5c346ba075bd57f5a62b"`;
 
-exports[`datatype > 1337 > hexadecimal > with prefix 1`] = `"0X5"`;
+exports[`datatype > 1337 > hexadecimal > with prefix 1`] = `"0x5"`;
 
 exports[`datatype > 1337 > json 1`] = `"{\\"foo\\":56052,\\"bar\\":21258,\\"bike\\":54308,\\"a\\":3397,\\"b\\":23538,\\"name\\":\\"X9@{:e=+kD\\",\\"prop\\":62850}"`;
 
diff --git a/test/datatype.spec.ts b/test/datatype.spec.ts
index dfbc105af5b..22b5306ca03 100644
--- a/test/datatype.spec.ts
+++ b/test/datatype.spec.ts
@@ -63,7 +63,11 @@ describe('datatype', () => {
         .it('with length', { length: 42 })
         .it('with prefix', { prefix: '0x' })
         .it('with casing', { case: 'lower' })
-        .it('with length and prefix', { length: 20, prefix: '0x' });
+        .it('with length, prefix, and casing', {
+          length: 20,
+          prefix: '0x',
+          case: 'lower',
+        });
     });
 
     t.it('json');

From e88494a3fb21d6d0511d963a375c12d3130695df Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Mon, 8 Aug 2022 13:22:50 -0400
Subject: [PATCH 12/16] fix: typo in example

---
 src/modules/datatype/index.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/modules/datatype/index.ts b/src/modules/datatype/index.ts
index 750313f36a2..10047b4d472 100644
--- a/src/modules/datatype/index.ts
+++ b/src/modules/datatype/index.ts
@@ -198,7 +198,7 @@ export class Datatype {
    * faker.datatype.hexadecimal({ length: 10 }) // 'AE13F044FB'
    * faker.datatype.hexadecimal({ prefix: '0x' }) // '0xE'
    * faker.datatype.hexadecimal({ case: 'lower' }) // 'f'
-   * faker.datatype.hexadecimal({ length: 10, prefix: '0x' }) // '0F12A974FB1'
+   * faker.datatype.hexadecimal({ length: 10, prefix: '0x' }) // '0xF12A974FB1'
    * faker.datatype.hexadecimal({ length: 10, case: 'lower' }) // 'eef38014fb'
    * faker.datatype.hexadecimal({ prefix: '0x', case: 'lower' }) // '0xd'
    * faker.datatype.hexadecimal({ length: 10, prefix: '0x', case: 'lower' }) // '0xfdc330a4b1'

From addfc252eceb1c69019e10103b3842c39826fe6b Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Mon, 8 Aug 2022 17:12:12 -0400
Subject: [PATCH 13/16] chore: apply code review suggestions from @ST-DDT

Co-authored-by: ST-DDT <st-ddt@gmx.de>
---
 src/modules/color/index.ts               |  4 +---
 src/modules/datatype/index.ts            | 26 ++++++++++++------------
 test/__snapshots__/datatype.spec.ts.snap | 12 +++--------
 test/datatype.spec.ts                    |  4 ++--
 4 files changed, 19 insertions(+), 27 deletions(-)

diff --git a/src/modules/color/index.ts b/src/modules/color/index.ts
index 921edaac5e5..d64b7750545 100644
--- a/src/modules/color/index.ts
+++ b/src/modules/color/index.ts
@@ -297,9 +297,7 @@ export class Color {
     let color: string | number[];
     let cssFunction: CSSFunction = 'rgb';
     if (format === 'hex') {
-      color = this.faker.datatype
-        .hexadecimal({ length: includeAlpha ? 8 : 6, prefix })
-        .slice(prefix.length);
+      color = this.faker.datatype.hexadecimal({ length: includeAlpha ? 8 : 6 });
       color = formatHexColor(color, options);
       return color;
     }
diff --git a/src/modules/datatype/index.ts b/src/modules/datatype/index.ts
index 10047b4d472..63111f31849 100644
--- a/src/modules/datatype/index.ts
+++ b/src/modules/datatype/index.ts
@@ -195,18 +195,18 @@ export class Datatype {
    *
    * @example
    * faker.datatype.hexadecimal() // 'B'
-   * faker.datatype.hexadecimal({ length: 10 }) // 'AE13F044FB'
+   * faker.datatype.hexadecimal({ length: 10 }) // 'aE13d044cB'
    * faker.datatype.hexadecimal({ prefix: '0x' }) // '0xE'
    * faker.datatype.hexadecimal({ case: 'lower' }) // 'f'
-   * faker.datatype.hexadecimal({ length: 10, prefix: '0x' }) // '0xF12A974FB1'
-   * faker.datatype.hexadecimal({ length: 10, case: 'lower' }) // 'eef38014fb'
+   * faker.datatype.hexadecimal({ length: 10, prefix: '0x' }) // '0xf12a974eB1'
+   * faker.datatype.hexadecimal({ length: 10, case: 'upper' }) // 'E3F38014FB'
    * faker.datatype.hexadecimal({ prefix: '0x', case: 'lower' }) // '0xd'
-   * faker.datatype.hexadecimal({ length: 10, prefix: '0x', case: 'lower' }) // '0xfdc330a4b1'
+   * faker.datatype.hexadecimal({ length: 10, prefix: '0x', case: 'mixed' }) // '0xAdE330a4D1'
    */
   hexadecimal(
-    options?:
-      | { length?: number; prefix?: string; case?: 'lower' | 'upper' }
-      | number
+    options:
+      | { length?: number; prefix?: string; case?: 'lower' | 'upper' | 'mixed' }
+      | number = {}
   ): string {
     if (typeof options === 'number') {
       deprecated({
@@ -220,9 +220,7 @@ export class Datatype {
       };
     }
 
-    const length = options?.length ?? 1;
-    const prefix = options?.prefix ?? '';
-    const letterCase = options?.case ?? 'upper';
+    const { length = 1, prefix = '', case: letterCase = 'mixed' } = options;
 
     let wholeString = '';
 
@@ -253,9 +251,11 @@ export class Datatype {
       ]);
     }
 
-    return letterCase === 'upper'
-      ? `${prefix}${wholeString.toUpperCase()}`
-      : `${prefix}${wholeString.toLowerCase()}`;
+    return letterCase === 'mixed'
+      ? `${prefix}${wholeString}`
+      : letterCase === 'lower'
+      ? `${prefix}${wholeString.toLowerCase()}`
+      : `${prefix}${wholeString.toUpperCase()}`;
   }
 
   /**
diff --git a/test/__snapshots__/datatype.spec.ts.snap b/test/__snapshots__/datatype.spec.ts.snap
index b527e10fdf6..97f2d4c64e1 100644
--- a/test/__snapshots__/datatype.spec.ts.snap
+++ b/test/__snapshots__/datatype.spec.ts.snap
@@ -74,9 +74,7 @@ exports[`datatype > 42 > hexadecimal > noArgs 1`] = `"8"`;
 
 exports[`datatype > 42 > hexadecimal > with casing 1`] = `"8"`;
 
-exports[`datatype > 42 > hexadecimal > with length 1`] = `"8BE4ABDD39321AD7D3FE01FFCE404F4D6DB0906BD8"`;
-
-exports[`datatype > 42 > hexadecimal > with length and prefix 1`] = `"0x8BE4ABDD39321AD7D3FE"`;
+exports[`datatype > 42 > hexadecimal > with length 1`] = `"8BE4ABdd39321aD7d3fe01FfCE404F4d6db0906bd8"`;
 
 exports[`datatype > 42 > hexadecimal > with length, prefix, and casing 1`] = `"0x8be4abdd39321ad7d3fe"`;
 
@@ -192,9 +190,7 @@ exports[`datatype > 1211 > hexadecimal > noArgs 1`] = `"E"`;
 
 exports[`datatype > 1211 > hexadecimal > with casing 1`] = `"e"`;
 
-exports[`datatype > 1211 > hexadecimal > with length 1`] = `"EADB42F0E3F4A973FAB0AEEFCE96DFCF49CD438DF9"`;
-
-exports[`datatype > 1211 > hexadecimal > with length and prefix 1`] = `"0xEADB42F0E3F4A973FAB0"`;
+exports[`datatype > 1211 > hexadecimal > with length 1`] = `"EaDB42F0e3f4A973fAB0AeefCE96DFCF49cD438dF9"`;
 
 exports[`datatype > 1211 > hexadecimal > with length, prefix, and casing 1`] = `"0xeadb42f0e3f4a973fab0"`;
 
@@ -310,9 +306,7 @@ exports[`datatype > 1337 > hexadecimal > noArgs 1`] = `"5"`;
 
 exports[`datatype > 1337 > hexadecimal > with casing 1`] = `"5"`;
 
-exports[`datatype > 1337 > hexadecimal > with length 1`] = `"5C346BA075BD57F5A62B82D72AF39CBBB07A98CBA8"`;
-
-exports[`datatype > 1337 > hexadecimal > with length and prefix 1`] = `"0x5C346BA075BD57F5A62B"`;
+exports[`datatype > 1337 > hexadecimal > with length 1`] = `"5c346ba075bd57F5A62B82d72AF39CBBB07a98cbA8"`;
 
 exports[`datatype > 1337 > hexadecimal > with length, prefix, and casing 1`] = `"0x5c346ba075bd57f5a62b"`;
 
diff --git a/test/datatype.spec.ts b/test/datatype.spec.ts
index 22b5306ca03..a57139fdd0c 100644
--- a/test/datatype.spec.ts
+++ b/test/datatype.spec.ts
@@ -357,9 +357,9 @@ describe('datatype', () => {
           const hex = faker.datatype.hexadecimal({
             prefix: '0x',
             length: 7,
-            case: 'lower',
+            case: 'upper',
           });
-          expect(hex).toMatch(/^(0x)[0-9a-f]+$/i);
+          expect(hex).toMatch(/^(0x)[0-9A-F]+$/i);
           expect(hex.substring(2)).toHaveLength(7);
         });
       });

From ec79eaf2099d6bf31b57b55423e7ec64734cd0a6 Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Mon, 8 Aug 2022 18:37:53 -0400
Subject: [PATCH 14/16] Update src/modules/datatype/index.ts

Co-authored-by: ST-DDT <ST-DDT@gmx.de>
---
 src/modules/datatype/index.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/modules/datatype/index.ts b/src/modules/datatype/index.ts
index 63111f31849..7b3d7815f61 100644
--- a/src/modules/datatype/index.ts
+++ b/src/modules/datatype/index.ts
@@ -191,7 +191,7 @@ export class Datatype {
    * @param options The optional options object.
    * @param options.length Length of the generated number. Defaults to `1`.
    * @param options.prefix Prefix for the generated number. Defaults to `''`.
-   * @param options.case Case of the generated number. Defaults to `'upper'`.
+   * @param options.case Case of the generated number. Defaults to `'mixed'`.
    *
    * @example
    * faker.datatype.hexadecimal() // 'B'

From b1a70549234afdcbd4e9939ded7387c0d2eaca68 Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Tue, 9 Aug 2022 10:33:58 -0400
Subject: [PATCH 15/16] Update src/modules/datatype/index.ts

Co-authored-by: Shinigami <chrissi92@hotmail.de>
---
 src/modules/datatype/index.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/modules/datatype/index.ts b/src/modules/datatype/index.ts
index 7b3d7815f61..db4e9cc73f3 100644
--- a/src/modules/datatype/index.ts
+++ b/src/modules/datatype/index.ts
@@ -212,7 +212,7 @@ export class Datatype {
       deprecated({
         deprecated: 'faker.datatype.hexadecimal(length)',
         proposed: 'faker.datatype.hexadecimal({ length })',
-        since: '7.4',
+        since: '7.5',
         until: '8.0',
       });
       options = {

From 24ffdd9988e0d07e6abba7af41eccb6577943f22 Mon Sep 17 00:00:00 2001
From: Eric Cheng <ericcheng9316@gmail.com>
Date: Tue, 9 Aug 2022 18:29:07 -0400
Subject: [PATCH 16/16] chore: apply code review suggestion

Co-authored-by: ST-DDT <ST-DDT@gmx.de>
Co-authored-by: Shinigami <chrissi92@hotmail.de>
---
 src/modules/datatype/index.ts | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/src/modules/datatype/index.ts b/src/modules/datatype/index.ts
index db4e9cc73f3..671e8c6c53d 100644
--- a/src/modules/datatype/index.ts
+++ b/src/modules/datatype/index.ts
@@ -251,11 +251,13 @@ export class Datatype {
       ]);
     }
 
-    return letterCase === 'mixed'
-      ? `${prefix}${wholeString}`
-      : letterCase === 'lower'
-      ? `${prefix}${wholeString.toLowerCase()}`
-      : `${prefix}${wholeString.toUpperCase()}`;
+    if (letterCase === 'upper') {
+      wholeString = wholeString.toUpperCase();
+    } else if (letterCase === 'lower') {
+      wholeString = wholeString.toLowerCase();
+    }
+
+    return `${prefix}${wholeString}`;
   }
 
   /**