Class: Markbridge::Renderers::Discourse::RenderContext

Inherits:
Object
  • Object
show all
Defined in:
lib/markbridge/renderers/discourse/render_context.rb

Overview

Immutable context for rendering that wraps the parent chain Provides query methods to ask about parent elements without the renderer knowing about specific element types

Uses a hash-based cache for O(1) parent lookups instead of O(depth) scans

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(parents = [], parent_cache: nil, html_mode: false) ⇒ RenderContext

Returns a new instance of RenderContext.



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# File 'lib/markbridge/renderers/discourse/render_context.rb', line 14

def initialize(parents = [], parent_cache: nil, html_mode: false)
  @parents = parents.freeze
  @depth = parents.size
  @parent_cache = parent_cache || build_cache(parents)
  @html_mode = html_mode
end

Instance Attribute Details

#depth ⇒ Object (readonly)

Returns the value of attribute depth.



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# File 'lib/markbridge/renderers/discourse/render_context.rb', line 12

def depth
  @depth
end

#parents ⇒ Object (readonly)

Returns the value of attribute parents.



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# File 'lib/markbridge/renderers/discourse/render_context.rb', line 12

def parents
  @parents
end

Instance Method Details

#count_parents(klass) ⇒ Integer

Count parents of given type O(1) instead of O(depth)

Parameters:

  • klass (Class)

Returns:

  • (Integer) 


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# File 'lib/markbridge/renderers/discourse/render_context.rb', line 62

def count_parents(klass)
  @parent_cache[klass]&.size || 0
end

#find_parent(klass) ⇒ AST::Element?

Find closest parent of given type O(1) hash lookup instead of O(depth) scan

Parameters:

  • klass (Class)

Returns:



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# File 'lib/markbridge/renderers/discourse/render_context.rb', line 54

def find_parent(klass)
  @parent_cache[klass]&.last
end

#has_parent?(klass) ⇒ Boolean

Check if parent of type exists O(1) check

Parameters:

  • klass (Class)

Returns:

  • (Boolean) 


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# File 'lib/markbridge/renderers/discourse/render_context.rb', line 70

def has_parent?(klass)
  !@parent_cache[klass].nil?
end

#html_mode? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/markbridge/renderers/discourse/render_context.rb', line 46

def html_mode?
  @html_mode
end

#root? ⇒ Boolean

Check if we’re at the root (no parents)

Returns:

  • (Boolean) 


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# File 'lib/markbridge/renderers/discourse/render_context.rb', line 76

def root?
  @depth.zero?
end

#with_html_mode(value) ⇒ RenderContext

Create new context with html_mode toggled Preserves parent chain and cache

Parameters:

  • value (Boolean)

Returns:



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# File 'lib/markbridge/renderers/discourse/render_context.rb', line 41

def with_html_mode(value)
  self.class.new(@parents, parent_cache: @parent_cache, html_mode: value)
end

#with_parent(element) ⇒ RenderContext

Create new context with element added to parent chain. Incrementally updates the cache (O(1)) instead of rebuilding from parents (O(depth)) — important for deeply-nested documents.

Parameters:

Returns:



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# File 'lib/markbridge/renderers/discourse/render_context.rb', line 26

def with_parent(element)
  new_parents = @parents + [element]

  new_cache = @parent_cache.dup
  element_class = element.class
  new_cache[element_class] ||= []
  new_cache[element_class] = new_cache[element_class] + [element]

  self.class.new(new_parents, parent_cache: new_cache, html_mode: @html_mode)
end