kemko/liquid
1
0
Fork 0
mirror of https://github.com/kemko/liquid.git synced 2026-01-01 15:55:40 +03:00
Code Issues Actions Packages Projects Releases Wiki Activity

Implicit variable scoping

Browse Source
This commit is contained in:
Florian Weingarten
2019-04-11 10:25:52 +01:00
parent b3b63a683f
commit af614f3a2e
15 changed files with 102 additions and 161 deletions
Download Patch File Download Diff File Expand all files Collapse all files

75
lib/liquid/context.rb
View File

@@ -12,12 +12,12 @@ module Liquid
#
# context['bob'] #=> nil class Context
class Context
attr_reader :scopes, :errors, :registers, :environments, :resource_limits
attr_reader :scope, :errors, :registers, :environments, :resource_limits
attr_accessor :exception_renderer, :template_name, :partial, :global_filter, :strict_variables, :strict_filters
def initialize(environments = {}, outer_scope = {}, registers = {}, rethrow_errors = false, resource_limits = nil)
@environments = [environments].flatten
@scopes = [(outer_scope || {})]
@scope = outer_scope || {}
@registers = registers
@errors = []
@partial = false
@@ -25,8 +25,6 @@ module Liquid
@resource_limits = resource_limits || ResourceLimits.new(Template.default_resource_limits)
squash_instance_assigns_with_environments
@this_stack_used = false
self.exception_renderer = Template.default_exception_renderer
if rethrow_errors
self.exception_renderer = ->(e) { raise }
@@ -35,6 +33,8 @@ module Liquid
@interrupts = []
@filters = []
@global_filter = nil
@stack_level = 0
end
def warnings
@@ -86,21 +86,9 @@ module Liquid
strainer.invoke(method, *args).to_liquid
end
# Push new local scope on the stack. use <tt>Context#stack</tt> instead
def push(new_scope = {})
@scopes.unshift(new_scope)
raise StackLevelError, "Nesting too deep".freeze if @scopes.length > Block::MAX_DEPTH
end
# Merge a hash of variables in the current local scope
def merge(new_scopes)
@scopes[0].merge!(new_scopes)
end
# Pop from the stack. use <tt>Context#stack</tt> instead
def pop
raise ContextError if @scopes.size == 1
@scopes.shift
@scope.merge!(new_scopes)
end
# Pushes a new local scope on the stack, pops it at the end of the block
@@ -111,32 +99,26 @@ module Liquid
# end
#
# context['var] #=> nil
def stack(new_scope = nil)
old_stack_used = @this_stack_used
if new_scope
push(new_scope)
@this_stack_used = true
else
@this_stack_used = false
def stack(*variable_names)
previous_values = {}
variable_names.each do |variable_name|
previous_values[variable_name] = @scope[variable_name]
end
yield
ensure
pop if @this_stack_used
@this_stack_used = old_stack_used
end
@stack_level += 1
raise StackLevelError, "Nesting too deep".freeze if @stack_level > Block::MAX_DEPTH
def clear_instance_assigns
@scopes[0] = {}
begin
yield
ensure
@scope.merge!(previous_values)
@stack_level -= 1
end
end
# Only allow String, Numeric, Hash, Array, Proc, Boolean or <tt>Liquid::Drop</tt>
def []=(key, value)
unless @this_stack_used
@this_stack_used = true
push({})
end
@scopes[0][key] = value
@scope[key] = value
end
# Look up variable, either resolve directly after considering the name. We can directly handle
@@ -161,26 +143,19 @@ module Liquid
# Fetches an object starting at the local scope and then moving up the hierachy
def find_variable(key, raise_on_not_found: true)
# This was changed from find() to find_index() because this is a very hot
# path and find_index() is optimized in MRI to reduce object allocation
index = @scopes.find_index { |s| s.key?(key) }
scope = @scopes[index] if index
variable = nil
scope = @scope if @scope.key?(key)
if scope.nil?
@environments.each do |e|
index = @environments.find_index do |e|
variable = lookup_and_evaluate(e, key, raise_on_not_found: raise_on_not_found)
# When lookup returned a value OR there is no value but the lookup also did not raise
# then it is the value we are looking for.
if !variable.nil? || @strict_variables && raise_on_not_found
scope = e
break
end
!variable.nil? || @strict_variables && raise_on_not_found
end
scope = @environments[index || -1]
end
scope ||= @environments.last || @scopes.last
variable ||= lookup_and_evaluate(scope, key, raise_on_not_found: raise_on_not_found)
variable = variable.to_liquid
@@ -213,10 +188,10 @@ module Liquid
end
def squash_instance_assigns_with_environments
@scopes.last.each_key do |k|
@scope.each_key do |k|
@environments.each do |env|
if env.key?(k)
scopes.last[k] = lookup_and_evaluate(env, k)
@scope[k] = lookup_and_evaluate(env, k)
break
end
end

2
lib/liquid/tags/assign.rb
View File

@@ -24,7 +24,7 @@ module Liquid
def render(context)
val = @from.render(context)
context.scopes.last[@to] = val
context[@to] = val
context.resource_limits.assign_score += assign_score_of(val)
''.freeze
end

2
lib/liquid/tags/capture.rb
View File

@@ -24,7 +24,7 @@ module Liquid
def render(context)
output = super
context.scopes.last[@to] = output
context[@to] = output
context.resource_limits.assign_score += output.bytesize
''.freeze
end

21
lib/liquid/tags/case.rb
View File

@@ -39,20 +39,19 @@ module Liquid
end
def render(context)
context.stack do
execute_else_block = true
execute_else_block = true
output = ''
@blocks.each do |block|
if block.else?
return block.attachment.render(context) if execute_else_block
elsif block.evaluate(context)
execute_else_block = false
output << block.attachment.render(context)
end
output = ''
@blocks.each do |block|
if block.else?
return block.attachment.render(context) if execute_else_block
elsif block.evaluate(context)
execute_else_block = false
output << block.attachment.render(context)
end
output
end
output
end
private

16
lib/liquid/tags/cycle.rb
View File

@@ -34,15 +34,13 @@ module Liquid
def render(context)
context.registers[:cycle] ||= {}
context.stack do
key = context.evaluate(@name)
iteration = context.registers[:cycle][key].to_i
result = context.evaluate(@variables[iteration])
iteration += 1
iteration = 0 if iteration >= @variables.size
context.registers[:cycle][key] = iteration
result
end
key = context.evaluate(@name)
iteration = context.registers[:cycle][key].to_i
result = context.evaluate(@variables[iteration])
iteration += 1
iteration = 0 if iteration >= @variables.size
context.registers[:cycle][key] = iteration
result
end
private

2
lib/liquid/tags/for.rb
View File

@@ -156,7 +156,7 @@ module Liquid
result = ''
context.stack do
context.stack('forloop', @variable_name) do
loop_vars = Liquid::ForloopDrop.new(@name, length, for_stack[-1])
for_stack.push(loop_vars)

10
lib/liquid/tags/if.rb
View File

@@ -40,14 +40,12 @@ module Liquid
end
def render(context)
context.stack do
@blocks.each do |block|
if block.evaluate(context)
return block.attachment.render(context)
end
@blocks.each do |block|
if block.evaluate(context)
return block.attachment.render(context)
end
''.freeze
end
''.freeze
end
private

14
lib/liquid/tags/ifchanged.rb
View File

@@ -1,15 +1,13 @@
module Liquid
class Ifchanged < Block
def render(context)
context.stack do
output = super
output = super
if output != context.registers[:ifchanged]
context.registers[:ifchanged] = output
output
else
''.freeze
end
if output != context.registers[:ifchanged]
context.registers[:ifchanged] = output
output
else
''.freeze
end
end
end

2
lib/liquid/tags/include.rb
View File

@@ -60,7 +60,7 @@ module Liquid
begin
context.template_name = template_name
context.partial = true
context.stack do
context.stack(context_variable_name, *@attributes.keys) do
@attributes.each do |key, value|
context[key] = context.evaluate(value)
end

2
lib/liquid/tags/table_row.rb
View File

@@ -31,7 +31,7 @@ module Liquid
cols = context.evaluate(@attributes['cols'.freeze]).to_i
result = "<tr class=\"row1\">\n"
context.stack do
context.stack('tablerowloop', @variable_name) do
tablerowloop = Liquid::TablerowloopDrop.new(length, cols)
context['tablerowloop'.freeze] = tablerowloop

28
lib/liquid/tags/unless.rb
View File

@@ -7,22 +7,20 @@ module Liquid
#
class Unless < If
def render(context)
context.stack do
# First condition is interpreted backwards ( if not )
first_block = @blocks.first
unless first_block.evaluate(context)
return first_block.attachment.render(context)
end
# After the first condition unless works just like if
@blocks[1..-1].each do |block|
if block.evaluate(context)
return block.attachment.render(context)
end
end
''.freeze
# First condition is interpreted backwards ( if not )
first_block = @blocks.first
unless first_block.evaluate(context)
return first_block.attachment.render(context)
end
# After the first condition unless works just like if
@blocks[1..-1].each do |block|
if block.evaluate(context)
return block.attachment.render(context)
end
end
''.freeze
end
end

2
performance/shopify/comment_form.rb
View File

@@ -15,7 +15,7 @@ class CommentForm < Liquid::Block
def render(context)
article = context[@variable_name]
context.stack do
context.stack('form') do
context['form'] = {
'posted_successfully?' => context.registers[:posted_successfully],
'errors' => context['comment.errors'],

2
performance/shopify/paginate.rb
View File

@@ -24,7 +24,7 @@ class Paginate < Liquid::Block
def render(context)
@context = context
context.stack do
context.stack('paginate') do
current_page = context['current_page'].to_i
pagination = {

33
test/integration/drop_test.rb
View File

@@ -1,14 +1,6 @@
require 'test_helper'
class ContextDrop < Liquid::Drop
def scopes
@context.scopes.size
end
def scopes_as_array
(1..@context.scopes.size).to_a
end
def loop_pos
@context['forloop.index']
end
@@ -194,31 +186,6 @@ class DropsTest < Minitest::Test
end
end
def test_scope
assert_equal '1', Liquid::Template.parse('{{ context.scopes }}').render!('context' => ContextDrop.new)
assert_equal '2', Liquid::Template.parse('{%for i in dummy%}{{ context.scopes }}{%endfor%}').render!('context' => ContextDrop.new, 'dummy' => [1])
assert_equal '3', Liquid::Template.parse('{%for i in dummy%}{%for i in dummy%}{{ context.scopes }}{%endfor%}{%endfor%}').render!('context' => ContextDrop.new, 'dummy' => [1])
end
def test_scope_though_proc
assert_equal '1', Liquid::Template.parse('{{ s }}').render!('context' => ContextDrop.new, 's' => proc{ |c| c['context.scopes'] })
assert_equal '2', Liquid::Template.parse('{%for i in dummy%}{{ s }}{%endfor%}').render!('context' => ContextDrop.new, 's' => proc{ |c| c['context.scopes'] }, 'dummy' => [1])
assert_equal '3', Liquid::Template.parse('{%for i in dummy%}{%for i in dummy%}{{ s }}{%endfor%}{%endfor%}').render!('context' => ContextDrop.new, 's' => proc{ |c| c['context.scopes'] }, 'dummy' => [1])
end
def test_scope_with_assigns
assert_equal 'variable', Liquid::Template.parse('{% assign a = "variable"%}{{a}}').render!('context' => ContextDrop.new)
assert_equal 'variable', Liquid::Template.parse('{% assign a = "variable"%}{%for i in dummy%}{{a}}{%endfor%}').render!('context' => ContextDrop.new, 'dummy' => [1])
assert_equal 'test', Liquid::Template.parse('{% assign header_gif = "test"%}{{header_gif}}').render!('context' => ContextDrop.new)
assert_equal 'test', Liquid::Template.parse("{% assign header_gif = 'test'%}{{header_gif}}").render!('context' => ContextDrop.new)
end
def test_scope_from_tags
assert_equal '1', Liquid::Template.parse('{% for i in context.scopes_as_array %}{{i}}{% endfor %}').render!('context' => ContextDrop.new, 'dummy' => [1])
assert_equal '12', Liquid::Template.parse('{%for a in dummy%}{% for i in context.scopes_as_array %}{{i}}{% endfor %}{% endfor %}').render!('context' => ContextDrop.new, 'dummy' => [1])
assert_equal '123', Liquid::Template.parse('{%for a in dummy%}{%for a in dummy%}{% for i in context.scopes_as_array %}{{i}}{% endfor %}{% endfor %}{% endfor %}').render!('context' => ContextDrop.new, 'dummy' => [1])
end
def test_access_context_from_drop
assert_equal '123', Liquid::Template.parse('{%for a in dummy%}{{ context.loop_pos }}{% endfor %}').render!('context' => ContextDrop.new, 'dummy' => [1, 2, 3])
end

52
test/unit/context_unit_test.rb
View File

@@ -102,21 +102,6 @@ class ContextUnitTest < Minitest::Test
assert_nil @context['does_not_exist']
end
def test_scoping
@context.push
@context.pop
assert_raises(Liquid::ContextError) do
@context.pop
end
assert_raises(Liquid::ContextError) do
@context.push
@context.pop
@context.pop
end
end
def test_length_query
@context['numbers'] = [1, 2, 3, 4]
@@ -170,20 +155,43 @@ class ContextUnitTest < Minitest::Test
def test_add_item_in_outer_scope
@context['test'] = 'test'
@context.push
assert_equal 'test', @context['test']
@context.pop
@context.stack('test') do
assert_equal 'test', @context['test']
end
assert_equal 'test', @context['test']
end
def test_add_item_in_inner_scope
@context.push
@context['test'] = 'test'
assert_equal 'test', @context['test']
@context.pop
@context.stack('test') do
@context['test'] = 'test'
assert_equal 'test', @context['test']
end
assert_nil @context['test']
end
def test_nested_scopes
@context['test'] = 1
@context.stack('test') do
assert_equal 1, @context['test']
@context['test'] = 2
assert_equal 2, @context['test']
@context.stack('test') do
assert_equal 2, @context['test']
@context['test'] = 3
assert_equal 3, @context['test']
end
assert_equal 2, @context['test']
end
assert_equal 1, @context['test']
end
def test_hierachical_data
@context['hash'] = { "name" => 'tobi' }
assert_equal 'tobi', @context['hash.name']