Module: Gemmy::Components::DynamicSteps

Defined in:
lib/gemmy/patches_loaded/components/dynamic_steps.rb

Overview

Mimics the Cucumber API:

{#step} runs a step
{#define_step} defines a step

The usage is the same as Cucumber:

define_step /I print (.+) (.+) times/ do |string, n|
  n.times { print string }
end

step "I print hello 2 times"
=> 'hellohello'

Like Cucumber, it will raise an error if there is > 1 matching step AmbiguousMatchError can be rescued if desired.

It also raises an error if no matcher was found

Defined Under Namespace

Classes: AmbiguousMatchError, NoMatchFoundError

Instance Method Summary collapse

Instance Method Details

#define_step(regex, &blk) ⇒ Object

Defines a regex => proc mapping A good pattern for regex is to use (.+) as match groups, and mirror those as sequential named parameters in the block.

Match groups are left-greedy, for example:

"1 2 3 4 5".match(/(.+) (.+)/).tap &:shift
# => ['1 2 3 4', '5']



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# File 'lib/gemmy/patches_loaded/components/dynamic_steps.rb', line 46

def define_step(regex, &blk)
  steps[regex] = blk
end

#find_matching_steps(string) ⇒ Hash

Searches the keys in @steps for regexes that match the string.

Parameters:

  • string (String)

Returns:

  • (Hash) —

    where keys are regexes and vals are hashes with signature: matches: [Array<String>] the String#match results proc: [Proc] the block mapped to the regex



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# File 'lib/gemmy/patches_loaded/components/dynamic_steps.rb', line 80

def find_matching_steps(string)
  matching_steps = steps.reduce({}) do |matching_steps, (regex, proc)|
    match_results = string.match(regex).to_a.tap &:shift
    if match_results.any_not? &:blank?
      matching_steps[regex] = { matches: match_results, proc: proc }
    end
    matching_steps
  end
end

#step(string) ⇒ Object

run a step. searches @step keys for regex which matches the string then runs the associated proc, passing the regex match results



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# File 'lib/gemmy/patches_loaded/components/dynamic_steps.rb', line 54

def step(string)
  matching_steps = find_matching_steps(string)
  if matching_steps.keys.length > 1
    # Failure, multiple matching steps
    raise(
      AmbiguousMatchError,
      "step #{string} matched: #{matching_steps.keys.join(", ")}"
    )
  elsif matching_steps.keys.length == 0
    # Failure, no matching step
    raise(
      NoMatchFoundError,
      "step #{string} had no match"
    )
  else
    # Success, run the proc
    matching_step = matching_steps.values[0]
    matching_step[:proc].call(*(matching_step[:matches]))
  end
end

#steps ⇒ Object 



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# File 'lib/gemmy/patches_loaded/components/dynamic_steps.rb', line 34

def steps
  @steps ||= {}
end