# assert_value

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Checks that two values are same and "magically" replaces expected value
with the actual in case the new behavior (and new actual value) is correct.
Support two kind of arguments: string and code block.

This check works with both Test/Unit and RSpec. See documentation and examples below:

## Testing String Values

It is better to start with no expected value

    assert_value "foo"

Then run tests as usual with "rake test". As a result you will see
diff between expected and actual values:

    Failure:
    @@ -1,0, +1,1 @@
    +foo
    Accept the new value: yes to all, no to all, yes, no? [Y/N/y/n] (y):

If you accept the new value your test will be automatically modified to

    assert_value "foo", <<-END
        foo
    END

## Testing Block Values

assert_value can take code block as an argument. If executed block raises exception then
exception message is returned as actual value:

    assert_value do
        nil+1
    end

Run tests

    Failure:
    @@ -1,0, +1,1 @@
    +Exception NoMethodError: undefined method `+' for nil:NilClass
    Accept the new value: yes to all, no to all, yes, no? [Y/N/y/n] (y): 

After the new value is accepted you get

    assert_value(<<-END) do
        Exception NoMethodError: undefined method `+' for nil:NilClass
    END
        nil + 1
    end

## Testing Values Stored in Files

Sometimes test string is too large to be inlined into the test source. Put it into the file instead:

    assert_value "foo", log: 'test/log/reference.txt'

## Additional Test/Unit Options:

    --no-interactive skips all questions and just reports failures
    --autoaccept prints diffs and automatically accepts all new actual values
    --no-canonicalize turns off expected and actual value canonicalization (see below for details)

Additional options can be passed during both single test file run and rake test run:

In Ruby 1.8:

    ruby test/unit/foo_test.rb -- --autoaccept
    rake test TESTOPTS="-- --autoaccept"

In Ruby 1.9:

    ruby test/unit/foo_test.rb --autoaccept
    rake test TESTOPTS="--autoaccept"

## RSpec

In specs you can either call assert_value directly or use "be_same_value_as" matcher:

    describe "spec with be_same_value_as matcher" do
        it "compares with inline value" do
            expect("foo").to be_same_value_as <<-END
                foo
            END
        end

        it "compares with inline block" do
            expect { "foo" }.to be_same_value_as <<-END
                foo
            END
        end

        it "compares with value in file" do
            expect("foo").to be_same_value_as(:log => 'test/logs/assert_value_with_files.log.ref')
        end
    end


## Canonicalization:

Before comparing expected and actual strings, assert_value canonicalizes both using these rules:

- indentation is ignored (except for indentation  relative to the first line of the expected/actual string)
- ruby-style comments after "#" are ignored
- empty lines are ignored
- trailing whitespaces are ignored

You can turn canonicalization off with --no-canonicalize option. This is useful
when you need to regenerate expected test strings.
To regenerate the whole test suite, run:

In Ruby 1.8:

    rake test TESTOPTS="-- --no-canonicalize --autoaccept"

In Ruby 1.9:

    rake test TESTOPTS="--no-canonicalize --autoaccept"


## Supported Rubies and Test Frameworks

| Framework / Ruby    | 1.8.7 | 1.9.3 | 2.0+ |
|---------------------|-------|-------|------|
| Test-Unit (bundled) | Yes   | No    | No   |
| Minitest (bundled)  | No    | Yes   | No   |
| Test-Unit (latest)  | No    | No    | Yes  |
| Minitest (latest)   | No    | No    | Yes  |
| Rspec 2.99          | Yes   | Yes   | No   |
| Rspec (latest)      | Yes   | Yes   | Yes  |

- ruby 1,8.7 came with bundled Test-unit 1.2.3 and cannot run latest Test-Unit
  and Minitest frameworks
- ruby 1.9.3 came with bundled Minitest 2.5.1 and cannot run other Test-Unit
  and MInitest frameworks
- RSpec 2.99 is the latest RSpec framework compatible with Rails 2.3

## Development


One way to setup development environment using rbenv:

```bash
# compile ruby
rbenv install 2.3.0

# set local version of ruby under rbenv
rbenv local 2.3.0

# install bundler
gem install bundle

# configure bundler
bundle config --local path .bundle/gems
bundle config --local bin .bundle/bin    # binstubs
bundle config   # to see current settings

# below seems to be necessary, having a Gemfile in
# subdirectory like
#    bundle config --local gemfile gemfiles/test-unit.bundled.gemfile
# breaks tests in old rubies
ln -s gemfiles/test-unit.bundled.gemfile Gemfile

# install gems
bundle install
```
## Run Tests

Test-Unit and Minitest
```
bundle exec rake test
```
RSpec 2.99
```
bundle exec rspec test
```

RSpec 3+
```
bundle exec rake spec
```

## Building The Gem
```
gem build assert_value.gemspec
ls assert_value-*.gem
gem push assert_value-*.gem
```

## Changelog

- 1.5: Improve support for various testing frameworks and Ruby versions:
       Ruby 2.2.2, 2.2.3, RSpec 2.x, 3.x, Test::Unit 2.x, 3.x, Minitest 4.x, 5.x
- 1.4: Fix RSpec support
- 1.3: Improve support for various testing frameworks, fix assertion counters
- 1.2: Rails 4.1 and minitest gem support
- 1.1: RSpec support
- 1.0: Rename to assert_value
- 0.7: Support Ruby 1.9's MiniTest
- 0.6: Support test execution on Mac
- 0.5: Support code blocks to assert_same
- 0.4: Added support for code blocks as argument
- 0.3: Ruby 1.9 is supported
- 0.2: Make assert_same useful as a standalone gem. Bugfixes
- 0.1: Initial release