From e0e9ca94c4abf80ed3ec71e57621e6aa14f12df9 Mon Sep 17 00:00:00 2001 From: Glenn Jackman Date: Wed, 24 Dec 2025 18:52:03 -0500 Subject: [PATCH] isbn-verifier --- config.json | 8 ++ exercises/practice/isbn-verifier/.busted | 5 ++ .../isbn-verifier/.docs/instructions.md | 42 +++++++++++ .../practice/isbn-verifier/.meta/config.json | 19 +++++ .../practice/isbn-verifier/.meta/example.moon | 15 ++++ .../isbn-verifier/.meta/spec_generator.moon | 5 ++ .../practice/isbn-verifier/.meta/tests.toml | 73 +++++++++++++++++++ .../practice/isbn-verifier/isbn_verifier.moon | 4 + .../isbn-verifier/isbn_verifier_spec.moon | 65 +++++++++++++++++ 9 files changed, 236 insertions(+) create mode 100644 exercises/practice/isbn-verifier/.busted create mode 100644 exercises/practice/isbn-verifier/.docs/instructions.md create mode 100644 exercises/practice/isbn-verifier/.meta/config.json create mode 100644 exercises/practice/isbn-verifier/.meta/example.moon create mode 100644 exercises/practice/isbn-verifier/.meta/spec_generator.moon create mode 100644 exercises/practice/isbn-verifier/.meta/tests.toml create mode 100644 exercises/practice/isbn-verifier/isbn_verifier.moon create mode 100644 exercises/practice/isbn-verifier/isbn_verifier_spec.moon diff --git a/config.json b/config.json index 915192e..85077cc 100644 --- a/config.json +++ b/config.json @@ -334,6 +334,14 @@ "practices": [], "prerequisites": [], "difficulty": 4 + }, + { + "slug": "isbn-verifier", + "name": "ISBN Verifier", + "uuid": "ea44facf-a0d2-499e-8837-06ee3fea896e", + "practices": [], + "prerequisites": [], + "difficulty": 4 } ] }, diff --git a/exercises/practice/isbn-verifier/.busted b/exercises/practice/isbn-verifier/.busted new file mode 100644 index 0000000..86b84e7 --- /dev/null +++ b/exercises/practice/isbn-verifier/.busted @@ -0,0 +1,5 @@ +return { + default = { + ROOT = { '.' } + } +} diff --git a/exercises/practice/isbn-verifier/.docs/instructions.md b/exercises/practice/isbn-verifier/.docs/instructions.md new file mode 100644 index 0000000..4a0244e --- /dev/null +++ b/exercises/practice/isbn-verifier/.docs/instructions.md @@ -0,0 +1,42 @@ +# Instructions + +The [ISBN-10 verification process][isbn-verification] is used to validate book identification numbers. +These normally contain dashes and look like: `3-598-21508-8` + +## ISBN + +The ISBN-10 format is 9 digits (0 to 9) plus one check character (either a digit or an X only). +In the case the check character is an X, this represents the value '10'. +These may be communicated with or without hyphens, and can be checked for their validity by the following formula: + +```text +(d₁ * 10 + d₂ * 9 + d₃ * 8 + d₄ * 7 + d₅ * 6 + d₆ * 5 + d₇ * 4 + d₈ * 3 + d₉ * 2 + d₁₀ * 1) mod 11 == 0 +``` + +If the result is 0, then it is a valid ISBN-10, otherwise it is invalid. + +## Example + +Let's take the ISBN-10 `3-598-21508-8`. +We plug it in to the formula, and get: + +```text +(3 * 10 + 5 * 9 + 9 * 8 + 8 * 7 + 2 * 6 + 1 * 5 + 5 * 4 + 0 * 3 + 8 * 2 + 8 * 1) mod 11 == 0 +``` + +Since the result is 0, this proves that our ISBN is valid. + +## Task + +Given a string the program should check if the provided string is a valid ISBN-10. +Putting this into place requires some thinking about preprocessing/parsing of the string prior to calculating the check digit for the ISBN. + +The program should be able to verify ISBN-10 both with and without separating dashes. + +## Caveats + +Converting from strings to numbers can be tricky in certain languages. +Now, it's even trickier since the check digit of an ISBN-10 may be 'X' (representing '10'). +For instance `3-598-21507-X` is a valid ISBN-10. + +[isbn-verification]: https://en.wikipedia.org/wiki/International_Standard_Book_Number diff --git a/exercises/practice/isbn-verifier/.meta/config.json b/exercises/practice/isbn-verifier/.meta/config.json new file mode 100644 index 0000000..3322343 --- /dev/null +++ b/exercises/practice/isbn-verifier/.meta/config.json @@ -0,0 +1,19 @@ +{ + "authors": [ + "glennj" + ], + "files": { + "solution": [ + "isbn_verifier.moon" + ], + "test": [ + "isbn_verifier_spec.moon" + ], + "example": [ + ".meta/example.moon" + ] + }, + "blurb": "Check if a given string is a valid ISBN-10 number.", + "source": "Converting a string into a number and some basic processing utilizing a relatable real world example.", + "source_url": "https://en.wikipedia.org/wiki/International_Standard_Book_Number#ISBN-10_check_digit_calculation" +} diff --git a/exercises/practice/isbn-verifier/.meta/example.moon b/exercises/practice/isbn-verifier/.meta/example.moon new file mode 100644 index 0000000..1a2c9f2 --- /dev/null +++ b/exercises/practice/isbn-verifier/.meta/example.moon @@ -0,0 +1,15 @@ +{ + is_valid: (str) -> + clean = str\gsub('-', '') + return false if #clean != 10 + + sum = 0 + for i = 1, 10 + char = clean\sub i, i + digit = tonumber char -- may return "fail" + digit = 10 if i == 10 and char == 'X' + return false if not digit + sum += digit * (11 - i) + + sum % 11 == 0 +} diff --git a/exercises/practice/isbn-verifier/.meta/spec_generator.moon b/exercises/practice/isbn-verifier/.meta/spec_generator.moon new file mode 100644 index 0000000..f925e05 --- /dev/null +++ b/exercises/practice/isbn-verifier/.meta/spec_generator.moon @@ -0,0 +1,5 @@ +{ + module_name: 'Isbn10', + generate_test: (case, level) -> + indent "assert.is_#{case.expected} Isbn10.is_valid #{quote case.input.isbn}", level +} diff --git a/exercises/practice/isbn-verifier/.meta/tests.toml b/exercises/practice/isbn-verifier/.meta/tests.toml new file mode 100644 index 0000000..17e18d4 --- /dev/null +++ b/exercises/practice/isbn-verifier/.meta/tests.toml @@ -0,0 +1,73 @@ +# This is an auto-generated file. +# +# Regenerating this file via `configlet sync` will: +# - Recreate every `description` key/value pair +# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications +# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion) +# - Preserve any other key/value pair +# +# As user-added comments (using the # character) will be removed when this file +# is regenerated, comments can be added via a `comment` key. + +[0caa3eac-d2e3-4c29-8df8-b188bc8c9292] +description = "valid isbn" + +[19f76b53-7c24-45f8-87b8-4604d0ccd248] +description = "invalid isbn check digit" + +[4164bfee-fb0a-4a1c-9f70-64c6a1903dcd] +description = "valid isbn with a check digit of 10" + +[3ed50db1-8982-4423-a993-93174a20825c] +description = "check digit is a character other than X" + +[9416f4a5-fe01-4b61-a07b-eb75892ef562] +description = "invalid check digit in isbn is not treated as zero" + +[c19ba0c4-014f-4dc3-a63f-ff9aefc9b5ec] +description = "invalid character in isbn is not treated as zero" + +[28025280-2c39-4092-9719-f3234b89c627] +description = "X is only valid as a check digit" + +[8005b57f-f194-44ee-88d2-a77ac4142591] +description = "only one check digit is allowed" + +[fdb14c99-4cf8-43c5-b06d-eb1638eff343] +description = "X is not substituted by the value 10" + +[f6294e61-7e79-46b3-977b-f48789a4945b] +description = "valid isbn without separating dashes" + +[185ab99b-3a1b-45f3-aeec-b80d80b07f0b] +description = "isbn without separating dashes and X as check digit" + +[7725a837-ec8e-4528-a92a-d981dd8cf3e2] +description = "isbn without check digit and dashes" + +[47e4dfba-9c20-46ed-9958-4d3190630bdf] +description = "too long isbn and no dashes" + +[737f4e91-cbba-4175-95bf-ae630b41fb60] +description = "too short isbn" + +[5458a128-a9b6-4ff8-8afb-674e74567cef] +description = "isbn without check digit" + +[70b6ad83-d0a2-4ca7-a4d5-a9ab731800f7] +description = "check digit of X should not be used for 0" + +[94610459-55ab-4c35-9b93-ff6ea1a8e562] +description = "empty isbn" + +[7bff28d4-d770-48cc-80d6-b20b3a0fb46c] +description = "input is 9 characters" + +[ed6e8d1b-382c-4081-8326-8b772c581fec] +description = "invalid characters are not ignored after checking length" + +[daad3e58-ce00-4395-8a8e-e3eded1cdc86] +description = "invalid characters are not ignored before checking length" + +[fb5e48d8-7c03-4bfb-a088-b101df16fdc3] +description = "input is too long but contains a valid isbn" diff --git a/exercises/practice/isbn-verifier/isbn_verifier.moon b/exercises/practice/isbn-verifier/isbn_verifier.moon new file mode 100644 index 0000000..c976b36 --- /dev/null +++ b/exercises/practice/isbn-verifier/isbn_verifier.moon @@ -0,0 +1,4 @@ +{ + is_valid: (input) -> + error 'Implement me' +} diff --git a/exercises/practice/isbn-verifier/isbn_verifier_spec.moon b/exercises/practice/isbn-verifier/isbn_verifier_spec.moon new file mode 100644 index 0000000..dee9bd1 --- /dev/null +++ b/exercises/practice/isbn-verifier/isbn_verifier_spec.moon @@ -0,0 +1,65 @@ +Isbn10 = require 'isbn_verifier' + +describe 'isbn-verifier', -> + it 'valid isbn', -> + assert.is_true Isbn10.is_valid '3-598-21508-8' + + pending 'invalid isbn check digit', -> + assert.is_false Isbn10.is_valid '3-598-21508-9' + + pending 'valid isbn with a check digit of 10', -> + assert.is_true Isbn10.is_valid '3-598-21507-X' + + pending 'check digit is a character other than X', -> + assert.is_false Isbn10.is_valid '3-598-21507-A' + + pending 'invalid check digit in isbn is not treated as zero', -> + assert.is_false Isbn10.is_valid '4-598-21507-B' + + pending 'invalid character in isbn is not treated as zero', -> + assert.is_false Isbn10.is_valid '3-598-P1581-X' + + pending 'X is only valid as a check digit', -> + assert.is_false Isbn10.is_valid '3-598-2X507-9' + + pending 'only one check digit is allowed', -> + assert.is_false Isbn10.is_valid '3-598-21508-96' + + pending 'X is not substituted by the value 10', -> + assert.is_false Isbn10.is_valid '3-598-2X507-5' + + pending 'valid isbn without separating dashes', -> + assert.is_true Isbn10.is_valid '3598215088' + + pending 'isbn without separating dashes and X as check digit', -> + assert.is_true Isbn10.is_valid '359821507X' + + pending 'isbn without check digit and dashes', -> + assert.is_false Isbn10.is_valid '359821507' + + pending 'too long isbn and no dashes', -> + assert.is_false Isbn10.is_valid '3598215078X' + + pending 'too short isbn', -> + assert.is_false Isbn10.is_valid '00' + + pending 'isbn without check digit', -> + assert.is_false Isbn10.is_valid '3-598-21507' + + pending 'check digit of X should not be used for 0', -> + assert.is_false Isbn10.is_valid '3-598-21515-X' + + pending 'empty isbn', -> + assert.is_false Isbn10.is_valid '' + + pending 'input is 9 characters', -> + assert.is_false Isbn10.is_valid '134456729' + + pending 'invalid characters are not ignored after checking length', -> + assert.is_false Isbn10.is_valid '3132P34035' + + pending 'invalid characters are not ignored before checking length', -> + assert.is_false Isbn10.is_valid '3598P215088' + + pending 'input is too long but contains a valid isbn', -> + assert.is_false Isbn10.is_valid '98245726788'