Module: Synvert::Core::NodeQuery

Defined in:

lib/synvert/core/node_query.rb,
lib/synvert/core/node_query/parser.racc.rb

Overview

NodeQuery defines a node query language, which is a css like syntax for matching nodes.

It supports the following selectors:

• AST node type: .class, .send

• attribute value: [receiver = nil], [message = create]

• attribute regex: [key=~/\A:([^'"]+)\z/], [key!~/\A:([^'"]+)\z/]

• attribute conditions: [message != nil], [value > 1], [value >= 1], [value < 1], [value <= 1]

• nested attribute: [caller.message = map], [arguments.size = 2]

• first or last child: .def:first-child, .send:last-child

• nth-child or nth-last-child: .def:nth-child(2), .send:nth-last-child(2)

• descendant: .class .send

• child: .class > .def

• following sibling: .def:first-child + .def

• subsequnt sibling: .def:first-child ~ .def

• has: .class:has(.def)

It also supports some custom selectors:

• nested selector: .send[arguments = [size = 2][first = .sym][last = .hash]]

• array value: .send[arguments = (a, b)]

• IN operator: .send[message IN (try, try!)]

• NOT IN operator: .send[message NOT IN (create, build)]

• INCLUDES operator: .send[arguments INCLUDES &block]

• dynamic attribute value: .hash > .pair

Examples:

# it matches methods call nodes, like `puts message` or `p message`
Synvert::Core::NodeQuery::Parser.parse('.send[receiver = nil][message IN (puts, p)]').query_nodes(node)

Defined Under Namespace

Modules: Compiler Classes: Lexer, Parser