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gstr

Gstr is a project mainly written in Smalltalk, it's free.

Extensions to GNU Smalltalk to make it look a bit more like Ruby

gstr

A totally pointless exercise in adding stuff to GNU Smalltalk to make it look more like Ruby.

The system expects a folder structure with a lib folder and then a tests folder within that.

scripts

There are two runner scripts - st-run and st-test.

st-run

st-run loads all the files in lib, then passes your arguments to st-run.st. The idea is that this will be something similar to rake, but I'm not quite sure how it works.

st-test

st-test loads all the files in lib, then all the files in lib/tests, creating a global TestSuite (accessible via TestSuite global.).

Each file in lib/tests is expected to add itself to this global TestSuite - for example, if your TestCase is called MyTestCase do the following:

TestSuite global addTest: MyTestCase buildSuite.

Smalltalk Image files

Currently, st-run and st-test just use the global image (and I have mine pre-loaded with SUnit, DBI and DBD-MySQL). Eventually I will add commands to generate an image into lib, and if found it will use that one by default. There will probably be two stages to this; a working image and an output image. The idea here is that you can work on all your source files, test and run them with the scripts against your working image (with SUnit and other packages pre-loaded). Then, when you want to do a release, you generate an output image, which loads all your lib files into the working image and then saves that. So your output image has all your code frozen into it, meaning edits are harder but it should be faster to startup (as well as easier to deploy).

Object Extensions

Object has a more traditional if statement:

self if: someCondition then: [do this]
self if: someCondition then: [do this] else: [do that].

BlockClosure gains if: and unless: methods:

[do something] if: someCondition.
[do something] unless: someCondition.

Mock Objects

There is a mock object that works differently to the mocha/RSpec style mocks.

You create the mock object, send it messages and then test what was sent.

mock:= Mock new.
mock doSomething.
mock doSomethingElse.

mock shouldHaveReceived: #doSomething "answers true"
mock shouldHaveReceived: #someOtherMessage "raises an exception as someOtherMessage was not received"

There will also be a mechanism for stubbing existing objects - not sure how to implement this yet, but it will look like this:

myInstance expects: #calculate with: { 1, 2 } andReturns: 3.

MyClass expects: #sayHello with: 'George' andReturns: 'Hello George'.

Testing

Blocks are extended to allow you to test the results.

[test code] shouldBe: true.
[test code] should: BeGreen.
[test code] should: BeWorth amount: 25. 

(where BeGreen and BeWorth are custom matchers)

To implement a matcher you need to subclass GSTR.Matcher and implement the matches: value instance method. If matched, return true, if not matched return false.

A sample implementation for BeGreen would be:

GSTR.Matcher subclass: BeGreen [
  matches: value [
    ^(value = #green).
  ]
]

If you need to pass parameters to your matcher then add a class initialisation method.

A sample implementation for BeWorth would be:

GSTR.Matcher subclass: BeWorth [
  | expectedValue |
  matches: value [
    ^(value = expectedValue).
  ]
  initWith: anExpectedValue [
    expectedValue:= anExpectedValue.
  ]
]

BeWorth class extend [
  amount: anExpectedAmount [
    | instance | 
    instance:= BeWorth new.
    instance initWith: anExpectedAmount.
  ]
] 

ORM

No idea yet.

Web Framework

Something built on SWAZOO - SWAZOO dispatches the request into a queue. One of a pool of worker threads picks up the request and matches it against the router (yeah, GST is green-threaded but it could be ported to a native-threaded VM). The router is configured in a Sinatra-like fashion - each route is associated with a block that actually does the work.

Story Driven Development

A Cucumber-alike ought to be pretty easy. What about testing web results? Port HTMLUnit and Celerity? What about WATIR?

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