lib/haml/compiler/children_compiler.rb
# frozen_string_literal: true
require 'haml/temple_line_counter'
module Haml
class Compiler
class ChildrenCompiler
def initialize
@lineno = 1
@multi_flattener = Temple::Filters::MultiFlattener.new
end
def compile(node, &block)
temple = [:multi]
return temple if node.children.empty?
temple << [:whitespace] if prepend_whitespace?(node)
node.children.each do |n|
rstrip_whitespace!(temple) if nuke_prev_whitespace?(n)
insert_newlines!(temple, n)
temple << moving_lineno(n) { block.call(n) }
temple << [:whitespace] if insert_whitespace?(n)
end
rstrip_whitespace!(temple) if nuke_inner_whitespace?(node)
temple
end
private
def insert_newlines!(temple, node)
(node.line - @lineno).times do
temple << [:newline]
end
@lineno = node.line
end
def moving_lineno(node, &block)
# before: As they may have children, we need to increment lineno before compilation.
case node.type
when :script, :silent_script
@lineno += 1
when :tag
[node.value[:dynamic_attributes].new, node.value[:dynamic_attributes].old].compact.each do |attribute_hash|
@lineno += attribute_hash.count("\n")
end
@lineno += 1 if node.children.empty? && node.value[:parse]
end
temple = block.call # compile
# after: filter may not have children, and for some dynamic filters we can't predict the number of lines.
case node.type
when :filter
@lineno += TempleLineCounter.count_lines(temple)
end
temple
end
def prepend_whitespace?(node)
return false unless %i[comment tag].include?(node.type)
!nuke_inner_whitespace?(node)
end
def nuke_inner_whitespace?(node)
case
when node.type == :tag
node.value[:nuke_inner_whitespace]
when node.parent.nil?
false
else
nuke_inner_whitespace?(node.parent)
end
end
def nuke_prev_whitespace?(node)
case node.type
when :tag
node.value[:nuke_outer_whitespace]
when :silent_script
!node.children.empty? && nuke_prev_whitespace?(node.children.first)
else
false
end
end
def nuke_outer_whitespace?(node)
return false if node.type != :tag
node.value[:nuke_outer_whitespace]
end
def rstrip_whitespace!(temple)
return if temple.size == 1
case temple[0]
when :multi
case temple[-1][0]
when :whitespace
temple.delete_at(-1)
when :multi, :block
rstrip_whitespace!(temple[-1])
end
when :block
_block, code, exp = temple
if code.start_with?(/\s*if\s/)
# Remove [:whitespace] before `end`
exp.replace(@multi_flattener.call(exp))
rstrip_whitespace!(exp)
# Remove [:whitespace] before `else` if exists
else_index = find_else_index(exp)
if else_index
whitespace_index = else_index - 1
while exp[whitespace_index] == [:newline]
whitespace_index -= 1
end
if exp[whitespace_index] == [:whitespace]
exp.delete_at(whitespace_index)
end
end
end
end
end
def find_else_index(temple)
multi, *args = temple
return nil if multi != :multi
args.each_with_index do |arg, index|
if arg[0] == :code && arg[1].match?(/\A\s*else\s*\z/)
return index + 1
end
end
nil
end
def insert_whitespace?(node)
return false if nuke_outer_whitespace?(node)
case node.type
when :doctype
node.value[:type] != 'xml'
when :comment, :plain, :tag
true
when :script
node.children.empty? && !nuke_inner_whitespace?(node)
when :filter
!%w[ruby].include?(node.value[:name])
else
false
end
end
end
end
end