added Pry.sessions and Pry#parent, for more info on pry sessions. Also completed more documentation

This commit is contained in:
John Mair 2011-01-14 01:35:46 +11:00
parent ead507210d
commit ce3532e7ca
3 changed files with 112 additions and 42 deletions

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@ -16,7 +16,7 @@ commands such as `show_method` and `jump_to`
* Read the [documentation](http://rdoc.info/github/banister/pry/master/file/README.markdown)
* See the [source code](http://github.com/banister/pry)
Example: Interacting with an object at runtime
Example: Interacting with an object at runtime
---------------------------------------
With the `Object#pry` method we can pry (open an irb-like session) on
@ -24,7 +24,7 @@ an object. In the example below we open a Pry session for the `Test` class and e
an instance variable. The current thread is halted for the duration of the session.
require 'pry'
class Test
def self.hello() "hello world" end
end
@ -54,13 +54,13 @@ effect:
You can also use the `Pry.start(obj)` or `pry(obj)` syntax to start a pry session on
`obj`. e.g
Pry.start 5
Pry.start(5)
Beginning Pry session for 5
pry(5)>
OR
pry 6
pry(6)
beginning Pry session for 6
pry(6)>
@ -103,7 +103,7 @@ command. E.g
2. 100
3. "friend"
=> nil
We can then jump back to any of the previous nesting levels by using
the `jump_to` command:
@ -113,7 +113,7 @@ the `jump_to` command:
=> 100
pry(Hello):1>
If we just want to go back one level of nesting we can of course
If we just want to go back one level of nesting we can of course
use the `quit` or `exit` or `back` commands.
To break out of all levels of Pry nesting and return immediately to the
@ -125,7 +125,7 @@ calling process use `exit_all`:
Ending Pry session for Hello
Ending Pry session for main
=> main
# program resumes here
Features and limitations
@ -167,7 +167,7 @@ invoke any of these methods directly depending on exactly what aspect of the fun
see [ripl](https://github.com/cldwalker/ripl)
* Pry's `show_method` and `show_doc` commands do not work
in Ruby 1.8.
Commands
-----------
@ -196,7 +196,7 @@ that is a hash of configuration options (discussed further, below).
* If, for some reason you do not want to 'loop' then use `Pry.new.rep()`; it
only performs the Read-Eval-Print section of the REPL - it ends the
session after just one line of input. It takes the same parameters as
`Pry#repl()`
`Pry#repl()`
* Likewise `Pry#re()` only performs the Read-Eval section of the REPL,
it returns the result of the evaluation or an Exception object in
case of error. It also takes the same parameters as `Pry#repl()`
@ -262,8 +262,8 @@ are:
Local customization (applied to a single Pry session) is done by
passing config hash options to `Pry.start()` or to `Pry.new()`; also the
same accessors as described above for the `Pry` class also exist for a
Pry instance.
same accessors as described above for the `Pry` class exist for a
Pry instance so that customization can occur during runtime.
### Input:
@ -278,7 +278,7 @@ this input by default:
Pry.input = StringIO.new("@x = 10\nexit")
Object.pry
Object.instance_variable_get(:@x) #=> 10
The above will execute the code in the `StringIO`
@ -291,19 +291,26 @@ session will hang as it loops indefinitely awaiting new input.
The settings for a specific session override the global settings
(discussed above). There are two ways to set input for a specific pry session: At the
point the session is started, or within the session itself:
point the session is started, or within the session itself (at runtime):
Here is the first case:
##### At session start
Pry.start(Object, :input => StringIO.new("@x = 10\nexit"))
Object.instance_variable_get(:@x) #=> 10
##### At runtime
If you want to set the input object within the session itself you use
the special `_pry_` local variable which represents the Pry instance
managing the current session; inside the session we type:
_pry_.input = StringIO.new("@x = 10\nexit")
Note we can also set the input object for the parent Pry session (if
the current session is nested) like so:
_pry_.parent.input = StringIO.new("@x = 10\nexit")
### Output
For output Pry accepts any object that implements the `puts` method. This
@ -317,27 +324,27 @@ this output by default:
Pry.output = StringIO.new
Object.pry
Object.instance_variable_get(:@x) #=> 10
#### Example: Setting output for a specific session
As per Input, given above, we set the local output as follows:
Here is the first case:
##### At session start
Pry.start(Object, :output => StringIO.new("@x = 10\nexit"))
Object.instance_variable_get(:@x) #=> 10
And to change output from within the session itself:
##### At runtime
_pry_.output = StringIO.new
### Commands
Pry commands are not methods; they are commands that are intercepted
and executed before a Ruby eval takes place. Pry comes with a default
command set, but these commands can be augmented or overriden by
command set (`Pry::Commands`), but these commands can be augmented or overriden by
user-specified ones.
A valid Pry command object must inherit from
@ -359,7 +366,7 @@ A valid Pry command object must inherit from
Then inside a pry session:
(pry)> hello john
pry(main)> hello john
hello john!
=> nil
@ -367,12 +374,12 @@ Then inside a pry session:
As in the case of `input` and `output`:
At session start:
##### At session start:
Pry.start(self, :commands => MyCommands)
From within the session:
##### At runtime:
_pry_.commands = MyCommands
#### The command API
@ -415,8 +422,51 @@ for you. Typing `help` in a Pry session will show a list of commands
to the user followed by their descriptions. Passing a parameter to
`help` with the command name will just return the description of that specific command.
### Hooks
Currently Pry supports just two hooks: `before_session` and
`after_session`. These hooks are invoked before a Pry session starts
and after a session ends respectively. The default hooks used are
stored in the `Pry::DEFAULT_HOOKS` and just output the text `"Beginning
Pry session for <obj>"` and `"Ending Pry session for <obj>"`.
#### Example: Setting global hooks
All subsequent Pry instances will use these hooks as default:
Pry.hooks = {
:before_session => proc { |out, obj| out.puts "Opened #{obj}" },
:after_session => proc { |out, obj| out.puts "Closed #{obj}" }
}
5.pry
Inside the session:
Opened 5
pry(5)> exit
Closed 5
Note that the `before_session` and `after_session` procs receive the
current session's output object and session receiver as parameters.
#### Example: Setting hooks for a specific session
Like all the other customization options, the global default (as
explained above) can be overriden for a specific session, either at
session start or during runtime.
##### At session start
Pry.start(self, :hooks => { :before_session => proc { puts "hello world!" },
:after_session => proc { puts "goodbye world!" }
})
##### At runtime
_pry_.hooks = { :before_session => proc { puts "puts "hello world!" } }
Contact
-------

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@ -20,7 +20,7 @@ class Pry
# This method should not need to be accessed directly.
# @return [Pry] The active Pry instance.
attr_accessor :active_instance
# Get/Set the object to use for input by default by all Pry instances.
# @return [#readline] The object to use for input by default by all
# Pry instances.
@ -57,6 +57,7 @@ class Pry
# prompts by default by all Pry instances.
attr_accessor :prompt
end
# Start a Pry REPL.
# @param [Object, Binding] target The receiver of the Pry session
# @param [Hash] options
@ -96,4 +97,11 @@ class Pry
def @nesting.level
last.is_a?(Array) ? last.first : nil
end
# Return all active Pry sessions.
# @return [Array<Pry>] Active Pry sessions.
def self.sessions
# last element in nesting array is the pry instance
nesting.map(&:last)
end
end

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@ -12,7 +12,7 @@ class Pry
# @param [Hash] options The optional configuration parameters.
# @option options [#readline] :input The object to use for input. (see input.rb)
# @option options [#puts] :output The object to use for output. (see output.rb)
# @option options [Pry::CommandBase] :commands The object to use for
# @option options [Pry::CommandBase] :commands The object to use for
# commands. (see commands.rb)
# @option options [Hash] :hooks The defined hook Procs (see hooks.rb)
# @option options [Array<Proc>] :default_prompt The array of Procs
@ -45,13 +45,25 @@ class Pry
self.class.nesting = v
end
# Return parent of current Pry session.
# @return [Pry] The parent of the current Pry session.
def parent
idx = Pry.sessions.index(self)
if idx > 0
Pry.sessions[idx - 1]
else
nil
end
end
# Execute the hook `hook_name`, if it is defined.
# @param [Symbol] hook_name The hook to execute
# @param [Array] args The arguments to pass to the hook.
def exec_hook(hook_name, *args, &block)
hooks[hook_name].call(*args, &block) if hooks[hook_name]
end
# Start a read-eval-print-loop.
# If no parameter is given, default to top-level (main).
# @param [Object, Binding] target The receiver of the Pry session
@ -63,7 +75,7 @@ class Pry
target_self = target.eval('self')
exec_hook :before_session, output, target_self
# cannot rely on nesting.level as
# nesting.level changes with new sessions
nesting_level = nesting.size
@ -73,26 +85,26 @@ class Pry
# Make sure special locals exist
target.eval("_pry_ = Pry.active_instance")
target.eval("_ = Pry.last_result")
break_level = catch(:breakout) do
nesting.push [nesting.size, target_self]
nesting.push [nesting.size, target_self, self]
loop do
rep(target)
rep(target)
end
end
nesting.pop
exec_hook :after_session, output, target_self
# keep throwing until we reach the desired nesting level
if nesting_level != break_level
throw :breakout, break_level
throw :breakout, break_level
end
target_self
end
# Perform a read-eval-print.
# If no parameter is given, default to top-level (main).
# @param [Object, Binding] target The receiver of the read-eval-print
@ -152,11 +164,11 @@ class Pry
process_commands(val, eval_string, target)
eval_string << "#{val}\n"
break eval_string if valid_expression?(eval_string)
end
end
# Process Pry commands. Pry commands are not Ruby methods and are evaluated
# prior to Ruby expressions.
# Commands can be modified/configured by the user: see `Pry::Commands`
@ -174,7 +186,7 @@ class Pry
if pattern
last_match = Regexp.last_match
options = {
:captures => last_match ? last_match.captures : nil,
:eval_string => eval_string,
@ -208,7 +220,7 @@ class Pry
input.readline
end
end
end
end
# Returns the appropriate prompt to use.
# This method should not need to be invoked directly.
@ -217,7 +229,7 @@ class Pry
# @param [Object] target_self The receiver of the Pry session.
# @return [String] The prompt.
def select_prompt(first_line, target_self)
if first_line
Array(prompt).first.call(target_self, nesting.level)
else
@ -238,10 +250,10 @@ class Pry
def valid_expression?(code)
!!Ripper::SexpBuilder.new(code).parse
end
else
require 'ruby_parser'
# Determine if a string of code is a valid Ruby expression.
# Ruby 1.9 uses Ripper, Ruby 1.8 uses RubyParser.
# @param [String] code The code to validate.
@ -257,7 +269,7 @@ class Pry
true
end
end
# Return a `Binding` object for `target` or return `target` if it is
# already a `Binding`.
# In the case where `target` is top-level then return `TOPLEVEL_BINDING`