tracks/javascript/exercises/luhn/README.md in trackler-2.2.1.94 vs tracks/javascript/exercises/luhn/README.md in trackler-2.2.1.95
- old
+ new
@@ -16,77 +16,80 @@
but they should be stripped before checking. All other non-digit characters
are disallowed.
## Example 1: valid credit card number
-```
+```text
4539 1488 0343 6467
```
The first step of the Luhn algorithm is to double every second digit,
starting from the right. We will be doubling
-```
+```text
4_3_ 1_8_ 0_4_ 6_6_
```
If doubling the number results in a number greater than 9 then subtract 9
from the product. The results of our doubling:
-```
+```text
8569 2478 0383 3437
```
Then sum all of the digits:
-```
+```text
8+5+6+9+2+4+7+8+0+3+8+3+3+4+3+7 = 80
```
If the sum is evenly divisible by 10, then the number is valid. This number is valid!
## Example 2: invalid credit card number
-```
+```text
8273 1232 7352 0569
```
Double the second digits, starting from the right
-```
+```text
7253 2262 5312 0539
```
Sum the digits
-```
+```text
7+2+5+3+2+2+6+2+5+3+1+2+0+5+3+9 = 57
```
57 is not evenly divisible by 10, so this number is not valid.
## Setup
-Go through the setup instructions for JavaScript to
-install the necessary dependencies:
+Go through the setup instructions for JavaScript to install the
+ necessary dependencies:
http://exercism.io/languages/javascript/installation
-## Making the Test Suite Pass
+## Running the test suite
-Execute the tests with:
+The provided test suite uses [Jasmine](https://jasmine.github.io/).
+You can install it by opening a terminal window and running the
+following command:
- jasmine <exercise-name>.spec.js
+```sh
+npm install -g jasmine
+```
-Replace `<exercise-name>` with the name of the current exercise. E.g., to
-test the Hello World exercise:
+Run the test suite from the exercise directory with:
- jasmine hello-world.spec.js
+```sh
+jasmine luhn.spec.js
+```
-In many test suites all but the first test have been skipped.
-
-Once you get a test passing, you can unskip the next one by
-changing `xit` to `it`.
+In many test suites all but the first test have been marked "pending".
+Once you get a test passing, activate the next one by changing `xit` to `it`.
## Source
The Luhn Algorithm on Wikipedia [http://en.wikipedia.org/wiki/Luhn_algorithm](http://en.wikipedia.org/wiki/Luhn_algorithm)