Class: Json::Merge::Emitter

Inherits:
Ast::Merge::EmitterBase
  • Object
show all
Defined in:
lib/json/merge/emitter.rb

Overview

Custom JSON emitter that preserves comments and formatting.
This class provides utilities for emitting JSON while maintaining
the original structure, comments, and style choices.

Inherits common emitter functionality from Ast::Merge::EmitterBase.

Examples:

Basic usage

emitter = Emitter.new
emitter.emit_object_start
emitter.emit_pair("key", '"value"')
emitter.emit_object_end

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#needs_comma ⇒ Boolean (readonly)

Returns Whether next item needs a comma.

Returns:

  • (Boolean) —

    Whether next item needs a comma



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# File 'lib/json/merge/emitter.rb', line 18

def needs_comma
  @needs_comma
end

Instance Method Details

#clear_subclass_state ⇒ Object

Clear subclass-specific state



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# File 'lib/json/merge/emitter.rb', line 26

def clear_subclass_state
  @needs_comma = false
end

#emit_array_element(value, inline_comment: nil) ⇒ Object

Emit an array element

Parameters:

  • value (String) —

    Value (already formatted)

  • inline_comment (String, nil) (defaults to: nil) —

    Optional inline comment



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# File 'lib/json/merge/emitter.rb', line 116

def emit_array_element(value, inline_comment: nil)
  add_comma_if_needed
  line = "#{current_indent}#{value}"
  line += " // #{inline_comment}" if inline_comment
  @lines << line
  @needs_comma = true
end

#emit_array_end ⇒ Object

Emit array end



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# File 'lib/json/merge/emitter.rb', line 93

def emit_array_end
  dedent
  @lines << "#{current_indent}]"
  @needs_comma = true
end

#emit_array_start(key = nil) ⇒ Object

Emit array start

Parameters:

  • key (String, nil) (defaults to: nil) —

    Key name if this array is a value in an object



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# File 'lib/json/merge/emitter.rb', line 81

def emit_array_start(key = nil)
  add_comma_if_needed
  @lines << if key
    "#{current_indent}\"#{key}\": ["
  else
    "#{current_indent}["
  end
  indent
  @needs_comma = false
end

#emit_block_comment(text) ⇒ Object

Emit a block comment

Parameters:

  • text (String) —

    Comment text



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# File 'lib/json/merge/emitter.rb', line 59

def emit_block_comment(text)
  @lines << "#{current_indent}/* #{text} */"
end

#emit_comment(text, inline: false) ⇒ Object

Emit a single-line comment

Parameters:

  • text (String) —

    Comment text (without //)

  • inline (Boolean) (defaults to: false) —

    Whether this is an inline comment



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# File 'lib/json/merge/emitter.rb', line 45

def emit_comment(text, inline: false)
  if inline
    # Inline comments are appended to the last line
    return if @lines.empty?

    @lines[-1] = "#{@lines[-1]} // #{text}"
  else
    @lines << "#{current_indent}// #{text}"
  end
end

#emit_nested_object_end ⇒ Object

Emit closing brace for nested object



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# File 'lib/json/merge/emitter.rb', line 134

def emit_nested_object_end
  dedent
  @lines << "#{current_indent}}"
  @needs_comma = true
end

#emit_nested_object_start(key) ⇒ Object

Emit a key with opening brace for nested object

Parameters:

  • key (String) —

    Key name



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# File 'lib/json/merge/emitter.rb', line 126

def emit_nested_object_start(key)
  add_comma_if_needed
  @lines << "#{current_indent}\"#{key}\": {"
  indent
  @needs_comma = false
end

#emit_object_end ⇒ Object

Emit object end



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# File 'lib/json/merge/emitter.rb', line 72

def emit_object_end
  dedent
  @lines << "#{current_indent}}"
  @needs_comma = true
end

#emit_object_start ⇒ Object

Emit object start



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# File 'lib/json/merge/emitter.rb', line 64

def emit_object_start
  add_comma_if_needed
  @lines << "#{current_indent}{"
  indent
  @needs_comma = false
end

#emit_pair(key, value, inline_comment: nil) ⇒ Object

Emit a key-value pair

Parameters:

  • key (String) —

    Key name (without quotes)

  • value (String) —

    Value (already formatted, e.g., ‘“string”’, ‘123’, ‘true’)

  • inline_comment (String, nil) (defaults to: nil) —

    Optional inline comment



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# File 'lib/json/merge/emitter.rb', line 104

def emit_pair(key, value, inline_comment: nil)
  add_comma_if_needed
  line = "#{current_indent}\"#{key}\": #{value}"
  line += " // #{inline_comment}" if inline_comment
  @lines << line
  @needs_comma = true
end

#emit_tracked_comment(comment) ⇒ Object

Emit a tracked comment from CommentTracker

Parameters:

  • comment (Hash) —

    Comment with :text, :indent, :block



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# File 'lib/json/merge/emitter.rb', line 32

def emit_tracked_comment(comment)
  indent = " " * (comment[:indent] || 0)
  @lines << if comment[:block]
    "#{indent}/* #{comment[:text]} */"
  else
    "#{indent}// #{comment[:text]}"
  end
end

#initialize_subclass_state(**options) ⇒ Object

Initialize subclass-specific state (comma tracking for JSON)



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# File 'lib/json/merge/emitter.rb', line 21

def initialize_subclass_state(**options)
  @needs_comma = false
end

#to_json ⇒ String

Get the output as a JSON string

Returns:

  • (String) 


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# File 'lib/json/merge/emitter.rb', line 143

def to_json
  to_s
end