Raised to indicate that a system exit should occur with the specified exit_code
A RequestSet groups a request to activate a set of dependencies.
nokogiri = Gem::Dependency.new 'nokogiri', '~> 1.6' pg = Gem::Dependency.new 'pg', '~> 0.14' set = Gem::RequestSet.new nokogiri, pg requests = set.resolve p requests.map { |r| r.full_name } #=> ["nokogiri-1.6.0", "mini_portile-0.5.1", "pg-0.17.0"]
S3URISigner implements AWS SigV4 for S3 Source to avoid a dependency on the aws-sdk-* gems More on AWS SigV4: docs.aws.amazon.com/AmazonS3/latest/API/sig-v4-authenticating-requests.html
The SourceList represents the sources rubygems has been configured to use. A source may be created from an array of sources:
Gem::SourceList.from %w[https://rubygems.example https://internal.example]
Or by adding them:
sources = Gem::SourceList.new sources << 'https://rubygems.example'
The most common way to get a SourceList is Gem.sources.
Gem::StubSpecification reads the stub: line from the gemspec. This prevents us having to eval the entire gemspec in order to find out certain information.
The UriFormatter handles URIs from user-input and escaping.
uf = Gem::UriFormatter.new 'example.com' p uf.normalize #=> 'http://example.com'
Represents a single line of code of a given source file
This object contains metadata about the line such as amount of indentation, if it is empty or not, and lexical data, such as if it has an ‘end` or a keyword in it.
Visibility of lines can be toggled off. Marking a line as invisible indicates that it should not be used for syntax checks. It’s functionally the same as commenting it out.
Example:
line = CodeLine.from_source("def foo\n").first line.number => 1 line.empty? # => false line.visible? # => true line.mark_invisible line.visible? # => false
Outputs code with highlighted lines
Whatever is passed to this class will be rendered even if it is “marked invisible” any filtering of output should be done before calling this class.
DisplayCodeWithLineNumbers.new(
lines: lines,
highlight_lines: [lines[2], lines[3]]
).call
# =>
1
2 def cat
> 3 Dir.chdir
> 4 end
5 end
6
Used for formatting invalid blocks
Explains syntax errors based on their source
example:
source = "def foo; puts 'lol'" # Note missing end explain ExplainSyntax.new( code_lines: CodeLine.from_source(source) ).call explain.errors.first # => "Unmatched keyword, missing `end' ?"
When the error cannot be determined by lexical counting then the parser is run against the input and the raw errors are returned.
Example:
source = "1 * " # Note missing a second number explain ExplainSyntax.new( code_lines: CodeLine.from_source(source) ).call explain.errors.first # => "syntax error, unexpected end-of-input"
Capture parse errors from Ripper
Prism returns the errors with their messages, but Ripper does not. To get them we must make a custom subclass.
Example:
puts RipperErrors.new(" def foo").call.errors # => ["syntax error, unexpected end-of-input, expecting ';' or '\\n'"]
Scans up/down from the given block
You can try out a change, stash it, or commit it to save for later
Example:
scanner = ScanHistory.new(code_lines: code_lines, block: block) scanner.scan( up: ->(_, _, _) { true }, down: ->(_, _, _) { true } ) scanner.changed? # => true expect(scanner.lines).to eq(code_lines) scanner.stash_changes expect(scanner.lines).to_not eq(code_lines)
Tracks which lines various code blocks have expanded to and which are still unexplored
Not a URI component.
URI is valid, bad usage is not.
YAML::Store provides the same functionality as PStore, except it uses YAML to dump objects instead of Marshal.
require 'yaml/store' Person = Struct.new :first_name, :last_name people = [Person.new("Bob", "Smith"), Person.new("Mary", "Johnson")] store = YAML::Store.new "test.store" store.transaction do store["people"] = people store["greeting"] = { "hello" => "world" } end
After running the above code, the contents of “test.store” will be:
--- people: - !ruby/struct:Person first_name: Bob last_name: Smith - !ruby/struct:Person first_name: Mary last_name: Johnson greeting: hello: world
Raised when a mathematical function is evaluated outside of its domain of definition.
For example, since cos returns values in the range -1..1, its inverse function acos is only defined on that interval:
Math.acos(42)
produces:
Math::DomainError: Numerical argument is out of domain - "acos"
A Process::Status contains information about a system process.
Thread-local variable $? is initially nil. Some methods assign to it a Process::Status object that represents a system process (either running or terminated):
`ruby -e "exit 99"` stat = $? # => #<Process::Status: pid 1262862 exit 99> stat.class # => Process::Status stat.to_i # => 25344 stat.stopped? # => false stat.exited? # => true stat.exitstatus # => 99
ConditionVariable objects augment class Mutex. Using condition variables, it is possible to suspend while in the middle of a critical section until a resource becomes available.
Example:
mutex = Thread::Mutex.new resource = Thread::ConditionVariable.new a = Thread.new { mutex.synchronize { # Thread 'a' now needs the resource resource.wait(mutex) # 'a' can now have the resource } } b = Thread.new { mutex.synchronize { # Thread 'b' has finished using the resource resource.signal } }