1 files changed, 321 insertions, 32 deletions

diff --git a/lib/prism/node_ext.rb b/lib/prism/node_ext.rb
index 264d3a5c1e..8a6624e76d 100644
--- a/lib/prism/node_ext.rb
+++ b/lib/prism/node_ext.rb
@@ -1,99 +1,388 @@
 # frozen_string_literal: true
+# :markup: markdown
+#--
+# rbs_inline: enabled
 
+#--
 # Here we are reopening the prism module to provide methods on nodes that aren't
 # templated and are meant as convenience methods.
+#++
 module Prism
-  class FloatNode < Node
-    # Returns the value of the node as a Ruby Float.
-    def value
-      Float(slice)
+  class Node
+    #: (*String replacements) -> void
+    def deprecated(*replacements) # :nodoc:
+      location = caller_locations(1, 1)&.[](0)&.label
+      suggest = replacements.map { |replacement| "#{self.class}##{replacement}" }
+
+      warn(<<~MSG, uplevel: 1, category: :deprecated)
+        [deprecation]: #{self.class}##{location} is deprecated and will be \
+        removed in the next major version. Use #{suggest.join("/")} instead.
+        #{(caller(1, 3) || []).join("\n")}
+      MSG
     end
   end
 
-  class ImaginaryNode < Node
-    # Returns the value of the node as a Ruby Complex.
-    def value
-      Complex(0, numeric.value)
+  module RegularExpressionOptions # :nodoc:
+    # Returns a numeric value that represents the flags that were used to create
+    # the regular expression.
+    #--
+    #: (Integer flags) -> Integer
+    def self.options(flags)
+      o = 0
+      o |= Regexp::IGNORECASE if flags.anybits?(RegularExpressionFlags::IGNORE_CASE)
+      o |= Regexp::EXTENDED if flags.anybits?(RegularExpressionFlags::EXTENDED)
+      o |= Regexp::MULTILINE if flags.anybits?(RegularExpressionFlags::MULTI_LINE)
+      o |= Regexp::FIXEDENCODING if flags.anybits?(RegularExpressionFlags::EUC_JP | RegularExpressionFlags::WINDOWS_31J | RegularExpressionFlags::UTF_8)
+      o |= Regexp::NOENCODING if flags.anybits?(RegularExpressionFlags::ASCII_8BIT)
+      o
     end
   end
 
-  class IntegerNode < Node
-    # Returns the value of the node as a Ruby Integer.
-    def value
-      Integer(slice)
+  class InterpolatedMatchLastLineNode < Node
+    # Returns a numeric value that represents the flags that were used to create
+    # the regular expression.
+    #--
+    #: () -> Integer
+    def options
+      RegularExpressionOptions.options(flags)
     end
   end
 
   class InterpolatedRegularExpressionNode < Node
     # Returns a numeric value that represents the flags that were used to create
     # the regular expression.
+    #--
+    #: () -> Integer
     def options
-      o = flags & (RegularExpressionFlags::IGNORE_CASE | RegularExpressionFlags::EXTENDED | RegularExpressionFlags::MULTI_LINE)
-      o |= Regexp::FIXEDENCODING if flags.anybits?(RegularExpressionFlags::EUC_JP | RegularExpressionFlags::WINDOWS_31J | RegularExpressionFlags::UTF_8)
-      o |= Regexp::NOENCODING if flags.anybits?(RegularExpressionFlags::ASCII_8BIT)
-      o
+      RegularExpressionOptions.options(flags)
     end
   end
 
-  class RationalNode < Node
-    # Returns the value of the node as a Ruby Rational.
-    def value
-      Rational(slice.chomp("r"))
+  class MatchLastLineNode < Node
+    # Returns a numeric value that represents the flags that were used to create
+    # the regular expression.
+    #--
+    #: () -> Integer
+    def options
+      RegularExpressionOptions.options(flags)
     end
   end
 
   class RegularExpressionNode < Node
     # Returns a numeric value that represents the flags that were used to create
     # the regular expression.
+    #--
+    #: () -> Integer
     def options
-      o = flags & (RegularExpressionFlags::IGNORE_CASE | RegularExpressionFlags::EXTENDED | RegularExpressionFlags::MULTI_LINE)
-      o |= Regexp::FIXEDENCODING if flags.anybits?(RegularExpressionFlags::EUC_JP | RegularExpressionFlags::WINDOWS_31J | RegularExpressionFlags::UTF_8)
-      o |= Regexp::NOENCODING if flags.anybits?(RegularExpressionFlags::ASCII_8BIT)
-      o
+      RegularExpressionOptions.options(flags)
+    end
+  end
+
+  private_constant :RegularExpressionOptions
+
+  module HeredocQuery # :nodoc:
+    # Returns true if this node was represented as a heredoc in the source code.
+    #--
+    #: (String? opening) -> bool?
+    def self.heredoc?(opening)
+      # @type self: InterpolatedStringNode | InterpolatedXStringNode | StringNode | XStringNode
+      opening&.start_with?("<<")
+    end
+  end
+
+  class InterpolatedStringNode < Node
+    # Returns true if this node was represented as a heredoc in the source code.
+    #--
+    #: () -> bool?
+    def heredoc?
+      HeredocQuery.heredoc?(opening)
+    end
+  end
+
+  class InterpolatedXStringNode < Node
+    # Returns true if this node was represented as a heredoc in the source code.
+    #--
+    #: () -> bool?
+    def heredoc?
+      HeredocQuery.heredoc?(opening)
+    end
+  end
+
+  class StringNode < Node
+    # Returns true if this node was represented as a heredoc in the source code.
+    #--
+    #: () -> bool?
+    def heredoc?
+      HeredocQuery.heredoc?(opening)
+    end
+
+    # Occasionally it's helpful to treat a string as if it were interpolated so
+    # that there's a consistent interface for working with strings.
+    #--
+    #: () -> InterpolatedStringNode
+    def to_interpolated
+      InterpolatedStringNode.new(
+        source,
+        -1,
+        location,
+        frozen? ? InterpolatedStringNodeFlags::FROZEN : 0,
+        opening_loc,
+        [copy(location: content_loc, opening_loc: nil, closing_loc: nil)],
+        closing_loc
+      )
+    end
+  end
+
+  class XStringNode < Node
+    # Returns true if this node was represented as a heredoc in the source code.
+    #--
+    #: () -> bool?
+    def heredoc?
+      HeredocQuery.heredoc?(opening)
+    end
+
+    # Occasionally it's helpful to treat a string as if it were interpolated so
+    # that there's a consistent interface for working with strings.
+    #--
+    #: () -> InterpolatedXStringNode
+    def to_interpolated
+      InterpolatedXStringNode.new(
+        source,
+        -1,
+        location,
+        flags,
+        opening_loc,
+        [StringNode.new(source, node_id, content_loc, 0, nil, content_loc, nil, unescaped)],
+        closing_loc
+      )
+    end
+  end
+
+  private_constant :HeredocQuery
+
+  class ImaginaryNode < Node
+    # Returns the value of the node as a Ruby Complex.
+    #--
+    #: () -> Complex
+    def value
+      Complex(0, numeric.value)
+    end
+  end
+
+  class RationalNode < Node
+    # Returns the value of the node as a Ruby Rational.
+    #--
+    #: () -> Rational
+    def value
+      Rational(numerator, denominator)
     end
   end
 
   class ConstantReadNode < Node
-    # Returns the list of parts for the full name of this constant. For example: [:Foo]
+    # Returns the list of parts for the full name of this constant.
+    # For example: [:Foo]
+    #--
+    #: () -> Array[Symbol]
     def full_name_parts
       [name]
     end
 
     # Returns the full name of this constant. For example: "Foo"
+    #--
+    #: () -> String
     def full_name
-      name.name
+      name.to_s
+    end
+  end
+
+  class ConstantWriteNode < Node
+    # Returns the list of parts for the full name of this constant.
+    # For example: [:Foo]
+    #--
+    #: () -> Array[Symbol]
+    def full_name_parts
+      [name]
+    end
+
+    # Returns the full name of this constant. For example: "Foo"
+    #--
+    #: () -> String
+    def full_name
+      name.to_s
     end
   end
 
   class ConstantPathNode < Node
-    # Returns the list of parts for the full name of this constant path. For example: [:Foo, :Bar]
+    # An error class raised when dynamic parts are found while computing a
+    # constant path's full name. For example:
+    # Foo::Bar::Baz -> does not raise because all parts of the constant path are
+    # simple constants
+    # var::Bar::Baz -> raises because the first part of the constant path is a
+    # local variable
+    class DynamicPartsInConstantPathError < StandardError; end
+
+    # An error class raised when error recovery nodes are found while computing a
+    # constant path's full name. For example:
+    # Foo:: -> raises because the constant path is missing the last part
+    class ErrorRecoveryNodesInConstantPathError < StandardError; end
+
+    # Returns the list of parts for the full name of this constant path.
+    # For example: [:Foo, :Bar]
+    #--
+    #: () -> Array[Symbol]
     def full_name_parts
-      parts = [child.name]
-      current = parent
+      parts = [] #: Array[Symbol]
+      current = self #: node?
 
       while current.is_a?(ConstantPathNode)
-        parts.unshift(current.child.name)
+        name = current.name
+        if name.nil?
+          raise ErrorRecoveryNodesInConstantPathError, "Constant path contains error recovery nodes. Cannot compute full name"
+        end
+
+        parts.unshift(name)
         current = current.parent
       end
 
+      if !current.is_a?(ConstantReadNode) && !current.nil?
+        raise DynamicPartsInConstantPathError, "Constant path contains dynamic parts. Cannot compute full name"
+      end
+
       parts.unshift(current&.name || :"")
     end
 
     # Returns the full name of this constant path. For example: "Foo::Bar"
+    #--
+    #: () -> String
     def full_name
       full_name_parts.join("::")
     end
   end
 
   class ConstantPathTargetNode < Node
-    # Returns the list of parts for the full name of this constant path. For example: [:Foo, :Bar]
+    # Returns the list of parts for the full name of this constant path.
+    # For example: [:Foo, :Bar]
+    #--
+    #: () -> Array[Symbol]
     def full_name_parts
-      (parent&.full_name_parts || [:""]).push(child.name)
+      parts =
+        case (parent = self.parent)
+        when ConstantPathNode, ConstantReadNode
+          parent.full_name_parts
+        when nil
+          [:""]
+        else
+          # e.g. self::Foo, (var)::Bar = baz
+          raise ConstantPathNode::DynamicPartsInConstantPathError, "Constant target path contains dynamic parts. Cannot compute full name"
+        end
+
+      if (name = self.name).nil?
+        raise ConstantPathNode::ErrorRecoveryNodesInConstantPathError, "Constant target path contains error recovery nodes. Cannot compute full name"
+      end
+
+      parts.push(name)
     end
 
     # Returns the full name of this constant path. For example: "Foo::Bar"
+    #--
+    #: () -> String
     def full_name
       full_name_parts.join("::")
     end
   end
+
+  class ConstantTargetNode < Node
+    # Returns the list of parts for the full name of this constant.
+    # For example: [:Foo]
+    #--
+    #: () -> Array[Symbol]
+    def full_name_parts
+      [name]
+    end
+
+    # Returns the full name of this constant. For example: "Foo"
+    #--
+    #: () -> String
+    def full_name
+      name.to_s
+    end
+  end
+
+  class ParametersNode < Node
+    # Mirrors the Method#parameters method.
+    #--
+    #: () -> Array[[Symbol, Symbol] | [Symbol]]
+    def signature
+      names = [] #: Array[[Symbol, Symbol] | [Symbol]]
+
+      requireds.each do |param|
+        names << (param.is_a?(MultiTargetNode) ? [:req] : [:req, param.name])
+      end
+
+      optionals.each { |param| names << [:opt, param.name] }
+
+      if (rest = self.rest).is_a?(RestParameterNode)
+        names << [:rest, rest.name || :*]
+      end
+
+      posts.each do |param|
+        case param
+        when MultiTargetNode
+          names << [:req]
+        when ErrorRecoveryNode
+          raise "Invalid syntax"
+        else
+          names << [:req, param.name]
+        end
+      end
+
+      # Regardless of the order in which the keywords were defined, the required
+      # keywords always come first followed by the optional keywords.
+      keyopt = [] #: Array[OptionalKeywordParameterNode]
+      keywords.each do |param|
+        if param.is_a?(OptionalKeywordParameterNode)
+          keyopt << param
+        else
+          names << [:keyreq, param.name]
+        end
+      end
+
+      keyopt.each { |param| names << [:key, param.name] }
+
+      case (keyword_rest = self.keyword_rest)
+      when ForwardingParameterNode
+        names.concat([[:rest, :*], [:keyrest, :**], [:block, :&]])
+      when KeywordRestParameterNode
+        names << [:keyrest, keyword_rest.name || :**]
+      when NoKeywordsParameterNode
+        names << [:nokey]
+      end
+
+      case (block = self.block)
+      when BlockParameterNode
+        names << [:block, block.name || :&]
+      when NoBlockParameterNode
+        names << [:noblock]
+      end
+
+      names
+    end
+  end
+
+  class CallNode < Node
+    # When a call node has the attribute_write flag set, it means that the call
+    # is using the attribute write syntax. This is either a method call to []=
+    # or a method call to a method that ends with =. Either way, the = sign is
+    # present in the source.
+    #
+    # Prism returns the message_loc _without_ the = sign attached, because there
+    # can be any amount of space between the message and the = sign. However,
+    # sometimes you want the location of the full message including the inner
+    # space and the = sign. This method provides that.
+    #--
+    #: () -> Location?
+    def full_message_loc
+      attribute_write? ? message_loc&.adjoin("=") : message_loc
+    end
+  end
 end