SilentUI is a UI choice that is absolutely silent.
Parses and sanitizes source into a lexically aware document
Internally the document is represented by an array with each index containing a CodeLine correlating to a line from the source code.
There are three main phases in the algorithm:
Sanitize/format input source
Search for invalid blocks
Format invalid blocks into something meaninful
This class handles the first part.
The reason this class exists is to format input source for better/easier/cleaner exploration.
The CodeSearch class operates at the line level so we must be careful to not introduce lines that look valid by themselves, but when removed will trigger syntax errors or strange behavior.
## Join Trailing slashes
Code with a trailing slash is logically treated as a single line:
1 it "code can be split" \ 2 "across multiple lines" do
In this case removing line 2 would add a syntax error. We get around this by internally joining the two lines into a single “line” object
## Logically Consecutive lines
Code that can be broken over multiple lines such as method calls are on different lines:
1 User. 2 where(name: "schneems"). 3 first
Removing line 2 can introduce a syntax error. To fix this, all lines are joined into one.
## Heredocs
A heredoc is an way of defining a multi-line string. They can cause many problems. If left as a single line, the parser would try to parse the contents as ruby code rather than as a string. Even without this problem, we still hit an issue with indentation:
1 foo = <<~HEREDOC 2 "Be yourself; everyone else is already taken."" 3 ― Oscar Wilde 4 puts "I look like ruby code" # but i'm still a heredoc 5 HEREDOC
If we didn’t join these lines then our algorithm would think that line 4 is separate from the rest, has a higher indentation, then look at it first and remove it.
If the code evaluates line 5 by itself it will think line 5 is a constant, remove it, and introduce a syntax errror.
All of these problems are fixed by joining the whole heredoc into a single line.
## Comments and whitespace
Comments can throw off the way the lexer tells us that the line logically belongs with the next line. This is valid ruby but results in a different lex output than before:
1 User. 2 where(name: "schneems"). 3 # Comment here 4 first
To handle this we can replace comment lines with empty lines and then re-lex the source. This removal and re-lexing preserves line index and document size, but generates an easier to work with document.
Multiple lines form a singular CodeBlock
Source code is made of multiple CodeBlocks.
Example:
code_block.to_s # => # def foo # puts "foo" # end code_block.valid? # => true code_block.in_valid? # => false
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
Searches code for a syntax error
There are three main phases in the algorithm:
Sanitize/format input source
Search for invalid blocks
Format invalid blocks into something meaninful
This class handles the part.
The bulk of the heavy lifting is done in:
- CodeFrontier (Holds information for generating blocks and determining if we can stop searching) - ParseBlocksFromLine (Creates blocks into the frontier) - BlockExpand (Expands existing blocks to search more code)
## Syntax error detection
When the frontier holds the syntax error, we can stop searching
search = CodeSearch.new(<<~EOM) def dog def lol end EOM search.call search.invalid_blocks.map(&:to_s) # => # => ["def lol\n"]
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
Ripper.lex is not guaranteed to lex the entire source document
This class guarantees the whole document is lex-ed by iteratively lexing the document where ripper stopped.
Prism likely doesn’t have the same problem. Once ripper support is removed we can likely reduce the complexity here if not remove the whole concept.
Example usage:
lex = LexAll.new(source: source) lex.each do |value| puts value.line end
Value object for accessing lex values
This lex:
[1, 0], :on_ident, "describe", CMDARG
Would translate into:
lex.line # => 1 lex.type # => :on_indent lex.token # => "describe"
Not a URI.
URI is valid, bad usage is not.
Raised on attempt to Ractor#take if there was an uncaught exception in the Ractor. Its cause will contain the original exception, and ractor is the original ractor it was raised in.
r = Ractor.new { raise "Something weird happened" } begin r.take rescue => e p e # => #<Ractor::RemoteError: thrown by remote Ractor.> p e.ractor == r # => true p e.cause # => #<RuntimeError: Something weird happened> end
Raised on an attempt to access an object which was moved in Ractor#send or Ractor.yield.
r = Ractor.new { sleep } ary = [1, 2, 3] r.send(ary, move: true) ary.inspect # Ractor::MovedError (can not send any methods to a moved object)
exception to wait for reading. see IO.select.
exception to wait for writing. see IO.select.
When using Psych.load to deserialize a YAML document, the document is translated to an intermediary AST. That intermediary AST is then translated in to a Ruby object graph.
In the opposite direction, when using Psych.dump, the Ruby object graph is translated to an intermediary AST which is then converted to a YAML document.
Psych::Nodes contains all of the classes that make up the nodes of a YAML AST. You can manually build an AST and use one of the visitors (see Psych::Visitors) to convert that AST to either a YAML document or to a Ruby object graph.
Here is an example of building an AST that represents a list with one scalar:
# Create our nodes stream = Psych::Nodes::Stream.new doc = Psych::Nodes::Document.new seq = Psych::Nodes::Sequence.new scalar = Psych::Nodes::Scalar.new('foo') # Build up our tree stream.children << doc doc.children << seq seq.children << scalar
The stream is the root of the tree. We can then convert the tree to YAML:
stream.to_yaml => "---\n- foo\n"
Or convert it to Ruby:
stream.to_ruby => [["foo"]]
YAML AST Requirements A valid YAML AST must have one Psych::Nodes::Stream at the root. A Psych::Nodes::Stream node must have 1 or more Psych::Nodes::Document nodes as children.
Psych::Nodes::Document nodes must have one and only one child. That child may be one of:
Psych::Nodes::Sequence and Psych::Nodes::Mapping nodes may have many children, but Psych::Nodes::Mapping nodes should have an even number of children.
All of these are valid children for Psych::Nodes::Sequence and Psych::Nodes::Mapping nodes:
Psych::Nodes::Scalar and Psych::Nodes::Alias are both terminal nodes and should not have any children.
The GC profiler provides access to information on GC runs including time, length and object space size.
Example:
GC::Profiler.enable require 'rdoc/rdoc' GC::Profiler.report GC::Profiler.disable
See also GC.count, GC.malloc_allocated_size and GC.malloc_allocations
The Observable module extended to DRb. See Observable for details.
Extends command line arguments array (ARGV) to parse itself.
Acceptable argument classes. Now contains DecimalInteger, OctalInteger and DecimalNumeric. See Acceptable argument classes (in source code).