From 9cfecd833c1290584a04f953d11128c045b634ef Mon Sep 17 00:00:00 2001 From: Andrew Scott Date: Sat, 28 Sep 2024 12:12:21 -0400 Subject: [PATCH] Python: completed Black Jack --- python/black-jack/.exercism/config.json | 27 ++ python/black-jack/.exercism/metadata.json | 1 + python/black-jack/HELP.md | 130 +++++++ python/black-jack/HINTS.md | 45 +++ python/black-jack/README.md | 395 ++++++++++++++++++++++ python/black-jack/black_jack.py | 110 ++++++ python/black-jack/black_jack_test.py | 114 +++++++ 7 files changed, 822 insertions(+) create mode 100644 python/black-jack/.exercism/config.json create mode 100644 python/black-jack/.exercism/metadata.json create mode 100644 python/black-jack/HELP.md create mode 100644 python/black-jack/HINTS.md create mode 100644 python/black-jack/README.md create mode 100644 python/black-jack/black_jack.py create mode 100644 python/black-jack/black_jack_test.py diff --git a/python/black-jack/.exercism/config.json b/python/black-jack/.exercism/config.json new file mode 100644 index 0000000..a23fa9e --- /dev/null +++ b/python/black-jack/.exercism/config.json @@ -0,0 +1,27 @@ +{ + "authors": [ + "Ticktakto", + "Yabby1997", + "limm-jk", + "OMEGA-Y", + "wnstj2007", + "pranasziaukas", + "bethanyG" + ], + "contributors": [ + "PaulT89" + ], + "files": { + "solution": [ + "black_jack.py" + ], + "test": [ + "black_jack_test.py" + ], + "exemplar": [ + ".meta/exemplar.py" + ] + }, + "icon": "poker", + "blurb": "Learn about comparisons by implementing some Black Jack judging rules." +} diff --git a/python/black-jack/.exercism/metadata.json b/python/black-jack/.exercism/metadata.json new file mode 100644 index 0000000..cd2483b --- /dev/null +++ b/python/black-jack/.exercism/metadata.json @@ -0,0 +1 @@ +{"track":"python","exercise":"black-jack","id":"c39a445c45914cf69f9cd468976225b8","url":"https://exercism.org/tracks/python/exercises/black-jack","handle":"Chomp1295","is_requester":true,"auto_approve":false} \ No newline at end of file diff --git a/python/black-jack/HELP.md b/python/black-jack/HELP.md new file mode 100644 index 0000000..970b1fa --- /dev/null +++ b/python/black-jack/HELP.md @@ -0,0 +1,130 @@ +# Help + +## Running the tests + +We use [pytest][pytest: Getting Started Guide] as our website test runner. +You will need to install `pytest` on your development machine if you want to run tests for the Python track locally. +You should also install the following `pytest` plugins: + +- [pytest-cache][pytest-cache] +- [pytest-subtests][pytest-subtests] + +Extended information can be found in our website [Python testing guide][Python track tests page]. + + +### Running Tests + +To run the included tests, navigate to the folder where the exercise is stored using `cd` in your terminal (_replace `{exercise-folder-location}` below with your path_). +Test files usually end in `_test.py`, and are the same tests that run on the website when a solution is uploaded. + +Linux/MacOS +```bash +$ cd {path/to/exercise-folder-location} +``` + +Windows +```powershell +PS C:\Users\foobar> cd {path\to\exercise-folder-location} +``` + +
+ +Next, run the `pytest` command in your terminal, replacing `{exercise_test.py}` with the name of the test file: + +Linux/MacOS +```bash +$ python3 -m pytest -o markers=task {exercise_test.py} +==================== 7 passed in 0.08s ==================== +``` + +Windows +```powershell +PS C:\Users\foobar> py -m pytest -o markers=task {exercise_test.py} +==================== 7 passed in 0.08s ==================== +``` + + +### Common options +- `-o` : override default `pytest.ini` (_you can use this to avoid marker warnings_) +- `-v` : enable verbose output. +- `-x` : stop running tests on first failure. +- `--ff` : run failures from previous test before running other test cases. + +For additional options, use `python3 -m pytest -h` or `py -m pytest -h`. + + +### Fixing warnings + +If you do not use `pytest -o markers=task` when invoking `pytest`, you might receive a `PytestUnknownMarkWarning` for tests that use our new syntax: + +```bash +PytestUnknownMarkWarning: Unknown pytest.mark.task - is this a typo? You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html +``` + +To avoid typing `pytest -o markers=task` for every test you run, you can use a `pytest.ini` configuration file. +We have made one that can be downloaded from the top level of the Python track directory: [pytest.ini][pytest.ini]. + +You can also create your own `pytest.ini` file with the following content: + +```ini +[pytest] +markers = + task: A concept exercise task. +``` + +Placing the `pytest.ini` file in the _root_ or _working_ directory for your Python track exercises will register the marks and stop the warnings. +More information on pytest marks can be found in the `pytest` documentation on [marking test functions][pytest: marking test functions with attributes] and the `pytest` documentation on [working with custom markers][pytest: working with custom markers]. + +Information on customizing pytest configurations can be found in the `pytest` documentation on [configuration file formats][pytest: configuration file formats]. + + +### Extending your IDE or Code Editor + +Many IDEs and code editors have built-in support for using `pytest` and other code quality tools. +Some community-sourced options can be found on our [Python track tools page][Python track tools page]. + +[Pytest: Getting Started Guide]: https://docs.pytest.org/en/latest/getting-started.html +[Python track tools page]: https://exercism.org/docs/tracks/python/tools +[Python track tests page]: https://exercism.org/docs/tracks/python/tests +[pytest-cache]:http://pythonhosted.org/pytest-cache/ +[pytest-subtests]:https://github.com/pytest-dev/pytest-subtests +[pytest.ini]: https://github.com/exercism/python/blob/main/pytest.ini +[pytest: configuration file formats]: https://docs.pytest.org/en/6.2.x/customize.html#configuration-file-formats +[pytest: marking test functions with attributes]: https://docs.pytest.org/en/6.2.x/mark.html#raising-errors-on-unknown-marks +[pytest: working with custom markers]: https://docs.pytest.org/en/6.2.x/example/markers.html#working-with-custom-markers + +## Submitting your solution + +You can submit your solution using the `exercism submit black_jack.py` command. +This command will upload your solution to the Exercism website and print the solution page's URL. + +It's possible to submit an incomplete solution which allows you to: + +- See how others have completed the exercise +- Request help from a mentor + +## Need to get help? + +If you'd like help solving the exercise, check the following pages: + +- The [Python track's documentation](https://exercism.org/docs/tracks/python) +- The [Python track's programming category on the forum](https://forum.exercism.org/c/programming/python) +- [Exercism's programming category on the forum](https://forum.exercism.org/c/programming/5) +- The [Frequently Asked Questions](https://exercism.org/docs/using/faqs) + +Should those resources not suffice, you could submit your (incomplete) solution to request mentoring. + +Below are some resources for getting help if you run into trouble: + +- [The PSF](https://www.python.org) hosts Python downloads, documentation, and community resources. +- [The Exercism Community on Discord](https://exercism.org/r/discord) +- [Python Community on Discord](https://pythondiscord.com/) is a very helpful and active community. +- [/r/learnpython/](https://www.reddit.com/r/learnpython/) is a subreddit designed for Python learners. +- [#python on Libera.chat](https://www.python.org/community/irc/) this is where the core developers for the language hang out and get work done. +- [Python Community Forums](https://discuss.python.org/) +- [Free Code Camp Community Forums](https://forum.freecodecamp.org/) +- [CodeNewbie Community Help Tag](https://community.codenewbie.org/t/help) +- [Pythontutor](http://pythontutor.com/) for stepping through small code snippets visually. + +Additionally, [StackOverflow](http://stackoverflow.com/questions/tagged/python) is a good spot to search for your problem/question to see if it has been answered already. + If not - you can always [ask](https://stackoverflow.com/help/how-to-ask) or [answer](https://stackoverflow.com/help/how-to-answer) someone else's question. \ No newline at end of file diff --git a/python/black-jack/HINTS.md b/python/black-jack/HINTS.md new file mode 100644 index 0000000..aaa0273 --- /dev/null +++ b/python/black-jack/HINTS.md @@ -0,0 +1,45 @@ +# Hints + +[The Python comparisons tutorial][python comparisons tutorial] and [Python comparisons examples][python comparisons examples] are a great introduction covering the content of this exercise. + +## 1. Calculate the value of a card + +- You can use the equality comparison operator `==` to determine if a card is an ace card: `card == 'A'`. +- You can use the containment operator `in` to determine if a substring is contained inside a string: `'Q' in 'KJQ'`. +- You can use the [`int` constructor][int constructor] to convert a `str` of an `int` to an `int`: `int('13')`. + +## 2. Determine which card has a higher value + +- Once you have defined the `value_of_card` function, you can call it from other functions. +- You can use the value comparison operators `>` and `<` to determine if specific cards are _greater than_ or _less than_ a given value: `3 < 12`. +- You can use the equality comparison operator `==` to determine if two values are equal to one another. + +## 3. Calculate the value of an ace + +- Once you have defined the `value_of_card` function, you can call it from other functions. +- You can use the order comparison operator `>` to decide the appropriate course of action here. + +## 4. Determine Blackjack + +- Remember, you can use the [`if`/`elif`/`else` syntax][if syntax] to handle different combinations of cards. +- You can chain BOTH comparison operators and boolean operators _arbitrarily_: `y < z < x` or `(y or z) and (x or z)` +- You can reuse the already implemented `value_of_card` function. + +## 5. Splitting pairs + +- You can reuse the already implemented `value_of_card` function. +- You can handle the `A` case (when at least one of the cards in an ace) separately. + +## 6. Doubling down + +- An `A` scored at 11 will never allow doubling down if there are two cards in the hand. +- Given the first point, you _should_ be able to reuse the already implemented `value_of_card` function. +- You can chain comparison operators _arbitrarily_: `y < z < x`. +- You can use the [conditional expression][conditional expression] (_sometimes called a "ternary operator"_) + to shorten simple `if`/`else` statements: `13 if letter == 'M' else 3`. + +[conditional expression]: https://docs.python.org/3/reference/expressions.html#conditional-expressions +[if syntax]: https://docs.python.org/3/tutorial/controlflow.html#if-statements +[int constructor]: https://docs.python.org/3/library/functions.html#int +[python comparisons examples]: https://www.tutorialspoint.com/python/comparison_operators_example.htm +[python comparisons tutorial]: https://docs.python.org/3/reference/expressions.html#comparisons \ No newline at end of file diff --git a/python/black-jack/README.md b/python/black-jack/README.md new file mode 100644 index 0000000..bd8d281 --- /dev/null +++ b/python/black-jack/README.md @@ -0,0 +1,395 @@ +# Black Jack + +Welcome to Black Jack on Exercism's Python Track. +If you need help running the tests or submitting your code, check out `HELP.md`. +If you get stuck on the exercise, check out `HINTS.md`, but try and solve it without using those first :) + +## Introduction + +## Comparisons + +Python supports the following basic comparison operators: + +| Operator | Operation | Description | +| -------- | -------------------------- | ------------------------------------------------------------------------- | +| `>` | "greater than" | `a > b` is `True` if `a` is **strictly** greater in value than `b` | +| `<` | "less than" | `a < b` is `True` if `a` is **strictly** less in value than `b` | +| `==` | "equal to" | `a == b` is `True` if `a` is **strictly** equal to `b` in value | +| `>=` | "greater than or equal to" | `a >= b` is `True` if `a > b` OR `a == b` in value | +| `<=` | "less than or equal to" | `a <= b` is `True` if `a < b` or `a == b` in value | +| `!=` | "not equal to" | `a != b` is `True` if `a == b` is `False` | +| `is` | "identity" | `a is b` is `True` if **_and only if_** `a` and `b` are the same _object_ | +| `is not` | "negated identity" | `a is not b` is `True` if `a` and `b` are **not** the same _object_ | +| `in` | "containment test" | `a in b` is `True` if `a` is member, subset, or element of `b` | +| `not in` | "negated containment test" | `a not in b` is `True` if `a` is not a member, subset, or element of `b` | + +They all have the same priority (_which is higher than that of [Boolean operations][boolean operations], but lower than that of arithmetic or bitwise operations_). + +## Comparison between different data types + +Objects that are different types (_except numeric types_) never compare equal by default. +Non-identical instances of a `class` will also _**not**_ compare as equal unless the `class` defines special [rich comparison][rich comparisons] methods that customize the default `object` comparison behavior. +Customizing via `rich comparisons` will be covered in a follow-on exercise. +For (much) more detail on this topic, see [Value comparisons][value comparisons] in the Python documentation. + +Numeric types are (mostly) an exception to this type matching rule. +An `integer` **can** be considered equal to a `float` (_or an [`octal`][octal] equal to a [`hexadecimal`][hex]_), as long as the types can be implicitly converted for comparison. + +For the other numeric types in the Python standard library ([complex][complex numbers], [decimal][decimal numbers], [fractions][rational numbers]), comparison operators are defined where they "make sense" (_where implicit conversion does not change the outcome_), but throw a `TypeError` if the underlying objects cannot be accurately converted for comparison. +For more information on the rules that python uses for _numeric conversion_, see [arithmetic conversions][arithmetic conversions] in the Python documentation. + +```python +>>> import fractions + +# A string cannot be converted to an int. +>>> 17 == '17' +False + +# An int can be converted to float for comparison. +>>> 17 == 17.0 +True + +# The fraction 6/3 can be converted to the int 2 +# The int 2 can be converted to 0b10 in binary. +>>> 6/3 == 0b10 +True + +# An int can be converted to a complex number with a 0 imaginary part. +>>> 17 == complex(17) +True + +# The fraction 2/5 can be converted to the float 0.4 +>>> 0.4 == 2/5 +True + +>>> complex(2/5, 1/2) == complex(0.4, 0.5) +True +``` + +Any ordered comparison of a number to a `NaN` (_not a number_) type is `False`. +A confusing side effect of Python's `NaN` definition is that `NaN` never compares equal to `NaN`. + +```python +>>> x = float('NaN') + +>>> 3 < x +False + +>>> x < 3 +False + +# NaN never compares equal to NaN +>>> x == x +False +``` + +## Comparing Strings + +Unlike numbers, strings (`str`) are compared [_lexicographically_][lexographic order], using their individual Unicode code points (_the result of passing each code point in the `str` to the built-in function [`ord()`][ord], which returns an `int`_). +If all code points in both strings match and are _**in the same order**_, the two strings are considered equal. +This comparison is done in a 'pair-wise' fashion - first-to-first, second-to-second, etc. +In Python 3.x, `str` and `bytes` cannot be directly coerced/compared. + +```python +>>> 'Python' > 'Rust' +False + +>>> 'Python' > 'JavaScript' +True + +# Examples with Mandarin. +# hello < goodbye +>>> '你好' < '再见' +True + +# ord() of first characters +>>> ord('你'), ord('再') +(20320, 20877) + +# ord() of second characters +>>> ord('好'), ord('见') +(22909, 35265) + +# And with Korean words. +# Pretty < beautiful. +>>> '예쁜' < '아름다운' +False + +>>> ord('예'), ord('아') +(50696, 50500) +``` + +## Comparison Chaining + +Comparison operators can be chained _arbitrarily_ -- meaning that they can be used in any combination of any length. +Note that the evaluation of an expression takes place from `left` to `right`. + +As an example, `x < y <= z` is equivalent to `x < y` `and` `y <= z`, except that `y` is evaluated **only once**. +In both cases, `z` is _not_ evaluated **at all** when `x < y` is found to be `False`. +This is often called `short-circuit evaluation` - the evaluation stops if the truth value of the expression has already been determined. + +`Short circuiting` is supported by various boolean operators, functions, and also by comparison chaining in Python. +Unlike many other programming languages, including `C`, `C++`, `C#`, and `Java`, chained expressions like `a < b < c` in Python have a conventional [mathematical interpretation][three way boolean comparison] and precedence. + +```python +>>> x = 2 +>>> y = 5 +>>> z = 10 + +>>> x < y < z +True + +>>> x < y > z +False + +>>> x > y < z +False +``` + +## Comparing object identity + +The operators `is` and `is not` test for object [_identity_][object identity], as opposed to object _value_. +An object's identity never changes after creation and can be found by using the [`id()`][id function] function. + +` is ` evaluates to `True` if _**and only if**_ `id()` == `id()`. +` is not ` yields the inverse. + +Due to their singleton status, `None` and `NotImplemented` should always be compared to items using `is` and `is not`. +See the Python reference docs on [value comparisons][value comparisons none] and [PEP8][pep8 programming recommendations] for more details on this convention. + +```python +>>> my_fav_numbers = [1, 2, 3] + +>>> your_fav_numbers = my_fav_numbers + +>>> my_fav_numbers is your_fav_numbers +True + +# The returned id will differ by system and python version. +>>> id(my_fav_numbers) +4517478208 + +# your_fav_numbers is only an alias pointing to the original my_fav_numbers object. +# Assigning a new name does not create a new object. +>>> id(your_fav_numbers) +4517478208 + + +>>> my_fav_numbers is not your_fav_numbers +False + +>>> my_fav_numbers is not None +True + +>>> my_fav_numbers is NotImplemented +False +``` + +## Membership comparisons + +The operators `in` and `not in` test for _membership_. +` in ` evaluates to `True` if `` is a member of `` (_if `` is a subset of or is contained within ``_), and evaluates `False` otherwise. +` not in ` returns the negation, or _opposite of_ ` in `. + +For string and bytes types, ` in ` is `True` _**if and only if**_ `` is a substring of ``. + +```python +# A set of lucky numbers. +>>> lucky_numbers = {11, 22, 33} +>>> 22 in lucky_numbers +True + +>>> 44 in lucky_numbers +False + +# A dictionary of employee information. +>>> employee = {'name': 'John Doe', + 'id': 67826, 'age': 33, + 'title': 'ceo'} + +# Checking for the membership of certain keys. +>>> 'age' in employee +True + +>>> 33 in employee +False + +>>> 'lastname' not in employee +True + +# Checking for substring membership +>>> name = 'Super Batman' +>>> 'Bat' in name +True + +>>> 'Batwoman' in name +False +``` + +[arithmetic conversions]: https://docs.python.org/3/reference/expressions.html?highlight=number%20conversion#arithmetic-conversions +[boolean operations]: https://docs.python.org/3/library/stdtypes.html#boolean-operations-and-or-not +[complex numbers]: https://docs.python.org/3/library/functions.html#complex +[decimal numbers]: https://docs.python.org/3/library/decimal.html +[hex]: https://docs.python.org/3/library/functions.html?highlight=hex#hex +[id function]: https://docs.python.org/3/library/functions.html#id +[lexographic order]: https://en.wikipedia.org/wiki/Lexicographic_order +[object identity]: https://docs.python.org/3/reference/datamodel.html +[octal]: https://docs.python.org/3/library/functions.html?#oct +[ord]: https://docs.python.org/3/library/functions.html#ord +[pep8 programming recommendations]: https://pep8.org/#programming-recommendations +[rational numbers]: https://docs.python.org/3/library/fractions.html +[rich comparisons]: https://docs.python.org/3/reference/datamodel.html#object.__lt__ +[three way boolean comparison]: https://en.wikipedia.org/wiki/Three-way_comparison +[value comparisons none]: https://docs.python.org/3/reference/expressions.html?highlight=none#value-comparisons +[value comparisons]: https://docs.python.org/3/reference/expressions.html?highlight=nan#value-comparisons + +## Instructions + +In this exercise you are going to implement some rules of [Blackjack][blackjack], +such as the way the game is played and scored. + +**Note** : In this exercise, _`A`_ means ace, _`J`_ means jack, _`Q`_ means queen, and _`K`_ means king. +Jokers are discarded. +A [standard French-suited 52-card deck][standard_deck] is assumed, but in most versions, several decks are shuffled together for play. + +## 1. Calculate the value of a card + +In Blackjack, it is up to each individual player if an ace is worth 1 or 11 points (_more on that later_). +Face cards (`J`, `Q`, `K`) are scored at 10 points and any other card is worth its "pip" (_numerical_) value. + +Define the `value_of_card()` function with parameter `card`. +The function should return the _numerical value_ of the passed-in card string. +Since an ace can take on multiple values (1 **or** 11), this function should fix the value of an ace card at 1 for the time being. +Later on, you will implement a function to determine the value of an ace card, given an existing hand. + +```python +>>> value_of_card('K') +10 + +>>> value_of_card('4') +4 + +>>> value_of_card('A') +1 +``` + +## 2. Determine which card has a higher value + +Define the `higher_card(, )` function having parameters `card_one` and `card_two`. +For scoring purposes, the value of `J`, `Q` or `K` is 10. +The function should return which card has the higher value for scoring. +If both cards have an equal value, return both. +Returning both cards can be done by using a comma in the `return` statement: + +```python +# Using a comma in a return creates a Tuple. Tuples will be covered in a later exercise. +>>> def returning_two_values(value_one, value_two): + return value_one, value_two + +>>> returning_two_values('K', '3') +('K', '3') +``` + +An ace can take on multiple values, so we will fix `A` cards to a value of 1 for this task. + +```python +>>> higher_card('K', '10') +('K', '10') + +>>> higher_card('4', '6') +'6' + +>>> higher_card('K', 'A') +'K' +``` + +## 3. Calculate the value of an ace + +As mentioned before, an ace can be worth _either_ 1 **or** 11 points. +Players try to get as close as possible to a score of 21, without going _over_ 21 (_going "bust"_). + +Define the `value_of_ace(, )` function with parameters `card_one` and `card_two`, which are a pair of cards already in the hand _before_ getting an ace card. +Your function will have to decide if the upcoming ace will get a value of 1 or a value of 11, and return that value. +Remember: the value of the hand with the ace needs to be as high as possible _without_ going over 21. + +**Hint**: if we already have an ace in hand, then the value for the upcoming ace would be 1. + +```python +>>> value_of_ace('6', 'K') +1 + +>>> value_of_ace('7', '3') +11 +``` + +## 4. Determine a "Natural" or "Blackjack" Hand + +If a player is dealt an ace (`A`) and a ten-card (10, `K`, `Q`, or `J`) as their first two cards, then the player has a score of 21. +This is known as a **blackjack** hand. + + +Define the `is_blackjack(, )` function with parameters `card_one` and `card_two`, which are a pair of cards. +Determine if the two-card hand is a **blackjack**, and return the boolean `True` if it is, `False` otherwise. + +**Note** : The score _calculation_ can be done in many ways. +But if possible, we'd like you to check if there is an ace and a ten-card **_in_** the hand (_or at a certain position_), as opposed to _summing_ the hand values. + +```python +>>> is_blackjack('A', 'K') +True + +>>> is_blackjack('10', '9') +False +``` + +## 5. Splitting pairs + +If the players first two cards are of the same value, such as two sixes, or a `Q` and `K` a player may choose to treat them as two separate hands. +This is known as "splitting pairs". + +Define the `can_split_pairs(, )` function with parameters `card_one` and `card_two`, which are a pair of cards. +Determine if this two-card hand can be split into two pairs. +If the hand can be split, return the boolean `True` otherwise, return `False` + +```python +>>> can_split_pairs('Q', 'K') +True + +>>> can_split_pairs('10', 'A') +False +``` + +## 6. Doubling down + +When the original two cards dealt total 9, 10, or 11 points, a player can place an additional bet equal to their original bet. +This is known as "doubling down". + +Define the `can_double_down(, )` function with parameters `card_one` and `card_two`, which are a pair of cards. +Determine if the two-card hand can be "doubled down", and return the boolean `True` if it can, `False` otherwise. + +```python +>>> can_double_down('A', '9') +True + +>>> can_double_down('10', '2') +False +``` + +[blackjack]: https://bicyclecards.com/how-to-play/blackjack/ +[standard_deck]: https://en.wikipedia.org/wiki/Standard_52-card_deck + +## Source + +### Created by + +- @Ticktakto +- @Yabby1997 +- @limm-jk +- @OMEGA-Y +- @wnstj2007 +- @pranasziaukas +- @bethanyG + +### Contributed to by + +- @PaulT89 \ No newline at end of file diff --git a/python/black-jack/black_jack.py b/python/black-jack/black_jack.py new file mode 100644 index 0000000..214bb8c --- /dev/null +++ b/python/black-jack/black_jack.py @@ -0,0 +1,110 @@ +"""Functions to help play and score a game of blackjack. + +How to play blackjack: https://bicyclecards.com/how-to-play/blackjack/ +"Standard" playing cards: https://en.wikipedia.org/wiki/Standard_52-card_deck +""" + + +def value_of_card(card): + """Determine the scoring value of a card. + + :param card: str - given card. + :return: int - value of a given card. See below for values. + + 1. 'J', 'Q', or 'K' (otherwise known as "face cards") = 10 + 2. 'A' (ace card) = 1 + 3. '2' - '10' = numerical value. + """ + + res = 0 + if card >= "J": + res = 10 + elif card == "A": + res = 1 + else: + res = int(card) + + return res + + +def higher_card(card_one, card_two): + """Determine which card has a higher value in the hand. + + :param card_one, card_two: str - cards dealt in hand. See below for values. + :return: str or tuple - resulting Tuple contains both cards if they are of equal value. + + 1. 'J', 'Q', or 'K' (otherwise known as "face cards") = 10 + 2. 'A' (ace card) = 1 + 3. '2' - '10' = numerical value. + """ + + card_one_val = value_of_card(card_one) + card_two_val = value_of_card(card_two) + + if card_one_val == card_two_val: + return (card_one, card_two) + + if card_one_val > card_two_val: + return card_one + + return card_two + + +def value_of_ace(card_one, card_two): + """Calculate the most advantageous value for the ace card. + + :param card_one, card_two: str - card dealt. See below for values. + :return: int - either 1 or 11 value of the upcoming ace card. + + 1. 'J', 'Q', or 'K' (otherwise known as "face cards") = 10 + 2. 'A' (ace card) = 11 (if already in hand) + 3. '2' - '10' = numerical value. + """ + + if (value_of_card(card_one) + value_of_card(card_two) >= 11) or "A" in ( + card_one, + card_two, + ): + return 1 + + return 11 + + +def is_blackjack(card_one, card_two): + """Determine if the hand is a 'natural' or 'blackjack'. + + :param card_one, card_two: str - card dealt. See below for values. + :return: bool - is the hand is a blackjack (two cards worth 21). + + 1. 'J', 'Q', or 'K' (otherwise known as "face cards") = 10 + 2. 'A' (ace card) = 11 (if already in hand) + 3. '2' - '10' = numerical value. + """ + + if card_one != "A" and card_two != "A": + return False + + if card_one == "A": + return value_of_card(card_two) + 11 == 21 + + return value_of_card(card_one) + 11 == 21 + + +def can_split_pairs(card_one, card_two): + """Determine if a player can split their hand into two hands. + + :param card_one, card_two: str - cards dealt. + :return: bool - can the hand be split into two pairs? (i.e. cards are of the same value). + """ + + return value_of_card(card_one) == value_of_card(card_two) + + +def can_double_down(card_one, card_two): + """Determine if a blackjack player can place a double down bet. + + :param card_one, card_two: str - first and second cards in hand. + :return: bool - can the hand can be doubled down? (i.e. totals 9, 10 or 11 points). + """ + + return 9 <= value_of_card(card_one) + value_of_card(card_two) <= 11 diff --git a/python/black-jack/black_jack_test.py b/python/black-jack/black_jack_test.py new file mode 100644 index 0000000..0962781 --- /dev/null +++ b/python/black-jack/black_jack_test.py @@ -0,0 +1,114 @@ +import unittest +import pytest + +from black_jack import ( + value_of_card, + higher_card, + value_of_ace, + is_blackjack, + can_split_pairs, + can_double_down + ) + + +class BlackJackTest(unittest.TestCase): + + @pytest.mark.task(taskno=1) + def test_value_of_card(self): + test_data = [('2', 2), ('5', 5), ('8', 8), + ('A', 1), ('10', 10), ('J', 10), + ('Q', 10), ('K', 10)] + + for variant, (card, expected) in enumerate(test_data, 1): + with self.subTest(f'variation #{variant}', card=card, expected=expected): + actual_result = value_of_card(card) + error_msg = (f'Called value_of_card({card}). ' + f'The function returned {actual_result} as the value of the {card} card, ' + f'but the test expected {expected} as the {card} card value.') + + self.assertEqual(actual_result, expected, msg=error_msg) + + + @pytest.mark.task(taskno=2) + def test_higher_card(self): + test_data = [('A', 'A', ('A', 'A')), + ('10', 'J', ('10', 'J')), + ('3', 'A', '3'), + ('3', '6', '6'), + ('Q', '10', ('Q', '10')), + ('4', '4', ('4', '4')), + ('9', '10', '10'), + ('6', '9', '9'), + ('4', '8', '8')] + + for variant, (card_one, card_two, expected) in enumerate(test_data, 1): + with self.subTest(f'variation #{variant}', card_one=card_one, card_two=card_two, expected=expected): + actual_result = higher_card(card_one, card_two) + error_msg = (f'Called higher_card({card_one}, {card_two}). ' + f'The function returned {actual_result}, ' + f'but the test expected {expected} as the result for the cards {card_one, card_two}.') + + self.assertEqual(actual_result, expected, msg=error_msg) + + @pytest.mark.task(taskno=3) + def test_value_of_ace(self): + test_data = [('2', '3', 11), ('3', '6', 11), ('5', '2', 11), + ('8', '2', 11), ('5', '5', 11), ('Q', 'A', 1), + ('10', '2', 1), ('7', '8', 1), ('J', '9', 1), + ('K', 'K', 1), ('2', 'A', 1), ('A', '2', 1)] + + for variant, (card_one, card_two, ace_value) in enumerate(test_data, 1): + with self.subTest(f'variation #{variant}', card_one=card_one, card_two=card_two, ace_value=ace_value): + actual_result = value_of_ace(card_one, card_two) + error_msg = (f'Called value_of_ace({card_one}, {card_two}). ' + f'The function returned {actual_result}, ' + f'but the test expected {ace_value} as the value of an ace card ' + f'when the hand includes {card_one, card_two}.') + + self.assertEqual(value_of_ace(card_one, card_two), ace_value, msg=error_msg) + + @pytest.mark.task(taskno=4) + def test_is_blackjack(self): + test_data = [(('A', 'K'), True), (('10', 'A'), True), + (('10', '9'), False), (('A', 'A'), False), + (('4', '7'), False), (('9', '2'), False), + (('Q', 'K'), False)] + + for variant, (hand, expected) in enumerate(test_data, 1): + with self.subTest(f'variation #{variant}', hand=hand, expected=expected): + actual_result = is_blackjack(*hand) + error_msg = (f'Called is_blackjack({hand[0]}, {hand[1]}). ' + f'The function returned {actual_result}, ' + f'but hand {hand} {"is" if expected else "is not"} a blackjack.') + + self.assertEqual(actual_result, expected, msg=error_msg) + + @pytest.mark.task(taskno=5) + def test_can_split_pairs(self): + test_data = [(('Q', 'K'), True), (('6', '6'), True), + (('A', 'A'), True),(('10', 'A'), False), + (('10', '9'), False)] + + for variant, (hand, expected) in enumerate(test_data, 1): + with self.subTest(f'variation #{variant}', input=hand, expected=expected): + actual_result = can_split_pairs(*hand) + error_msg = (f'Called can_split_pairs({hand[0]}, {hand[1]}). ' + f'The function returned {actual_result}, ' + f'but hand {hand} {"can" if expected else "cannot"} be split into pairs.') + + self.assertEqual(actual_result, expected, msg=error_msg) + + @pytest.mark.task(taskno=6) + def test_can_double_down(self): + test_data = [(('A', '9'), True), (('K', 'A'), True), + (('4', '5'), True),(('A', 'A'), False), + (('10', '2'), False), (('10', '9'), False)] + + for variant, (hand, expected) in enumerate(test_data, 1): + with self.subTest(f'variation #{variant}', hand=hand, expected=expected): + actual_result = can_double_down(*hand) + error_msg = (f'Called can_double_down({hand[0]}, {hand[1]}). ' + f'The function returned {actual_result}, ' + f'but hand {hand} {"can" if expected else "cannot"} be doubled down.') + + self.assertEqual(actual_result, expected, msg=error_msg)