Commit Graph
33 Commits
Author SHA1 Message Date
Charles-P. ClermontandGuilherme Carreiro 94bbf6ca32 Make it possible to safe_parse subsets of expressions
e.g. sometimes you want to only accept strings | lookups.
{% render snippetName %} for example. snippetName is a string right now.
We don't want safe_parse_expression because this would allow snippetName
to be a number, a boolean, etc. But we still want to strict parse this.

So what we'll do is use parse_expression(string, safe: true), this is
an optional opt-in to say "I know what I'm doing". Usually that's
because you're using the output of Parser#something as the input of
parse_expression.

It is true that Parser#expression is subset of Expression.parse, it is
not true of the opposite (e.g. Expression.parse doesn't care about .5
and happily parses that as a global lookup of the variable named "5",
Parser#expression throws for that.)

diff --git a/lib/liquid/condition.rb b/lib/liquid/condition.rb
index e5c321dc..9ab350f0 100644
--- a/lib/liquid/condition.rb
+++ b/lib/liquid/condition.rb
@@ -48,8 +48,8 @@ module Liquid
       @@operators
     end

-    def self.parse_expression(parse_context, markup)
-      @@method_literals[markup] || parse_context.parse_expression(markup)
+    def self.parse_expression(parse_context, markup, safe: false)
+      @@method_literals[markup] || parse_context.parse_expression(markup, safe: safe)
     end

     attr_reader :attachment, :child_condition
diff --git a/lib/liquid/parse_context.rb b/lib/liquid/parse_context.rb
index 1c59fe4a..82cf5768 100644
--- a/lib/liquid/parse_context.rb
+++ b/lib/liquid/parse_context.rb
@@ -51,13 +51,13 @@ module Liquid
     end

     def safe_parse_expression(parser)
-      Expression.safe_parse(parser)
+      Expression.safe_parse(parser, @string_scanner, @expression_cache)
     end

-    def parse_expression(markup)
+    def parse_expression(markup, safe: false)
       # todo(guilherme): remove this once rigid mode is fully using safe_parse_expression
-      # raise Liquid::InternalError, "parse_expression is not supported in rigid mode" if @error_mode == :rigid
-      puts("🚨 parse_expression used in rigid mode") if @error_mode == :rigid
+      # raise Liquid::InternalError, "parse_expression is not supported in rigid mode" if !safe && @error_mode == :rigid
+      puts("🚨 parse_expression used in rigid mode") if !safe && @error_mode == :rigid

       Expression.parse(markup, @string_scanner, @expression_cache)
     end
diff --git a/lib/liquid/tag.rb b/lib/liquid/tag.rb
index 656d2e47..374ee511 100644
--- a/lib/liquid/tag.rb
+++ b/lib/liquid/tag.rb
@@ -72,8 +72,8 @@ module Liquid
       parse_context.safe_parse_expression(parser)
     end

-    def parse_expression(markup)
-      parse_context.parse_expression(markup)
+    def parse_expression(markup, safe: false)
+      parse_context.parse_expression(markup, safe: safe)
     end
   end
 end
diff --git a/lib/liquid/tags/for.rb b/lib/liquid/tags/for.rb
index c2be5db1..3182983b 100644
--- a/lib/liquid/tags/for.rb
+++ b/lib/liquid/tags/for.rb
@@ -93,7 +93,7 @@ module Liquid
       raise SyntaxError, options[:locale].t("errors.syntax.for_invalid_in") unless p.id?('in')

       collection_name  = p.expression
-      @collection_name = parse_expression(collection_name)
+      @collection_name = parse_expression(collection_name, safe: true)

       @name     = "#{@variable_name}-#{collection_name}"
       @reversed = p.id?('reversed')
diff --git a/lib/liquid/tags/if.rb b/lib/liquid/tags/if.rb
index 342374f1..e25d6250 100644
--- a/lib/liquid/tags/if.rb
+++ b/lib/liquid/tags/if.rb
@@ -81,8 +81,8 @@ module Liquid
       block.attach(new_body)
     end

-    def parse_expression(markup)
-      Condition.parse_expression(parse_context, markup)
+    def parse_expression(markup, safe: false)
+      Condition.parse_expression(parse_context, markup, safe: safe)
     end

     def lax_parse(markup)
@@ -124,9 +124,9 @@ module Liquid
     end

     def parse_comparison(p)
-      a = parse_expression(p.expression)
+      a = parse_expression(p.expression, safe: true)
       if (op = p.consume?(:comparison))
-        b = parse_expression(p.expression)
+        b = parse_expression(p.expression, safe: true)
         Condition.new(a, op, b)
       else
         Condition.new(a)
diff --git a/lib/liquid/tags/include.rb b/lib/liquid/tags/include.rb
index 6cdbfd6f..b72a235b 100644
--- a/lib/liquid/tags/include.rb
+++ b/lib/liquid/tags/include.rb
@@ -87,10 +87,11 @@ module Liquid
     def rigid_parse(markup)
       p = @parse_context.new_parser(markup)

-      template_name = p.expression
+      @template_name_expr = safe_parse_expression(p)
       with_or_for = p.id?("for") || p.id?("with") || nil
+      @variable_name_expr = nil
       if with_or_for
-        variable_name = p.expression
+        @variable_name_expr = parse_expression(p.consume(:id), safe: true)
       end

       alias_name = nil
@@ -98,8 +99,6 @@ module Liquid
         alias_name = p.consume(:id)
       end

-      @template_name_expr = parse_expression(template_name)
-      @variable_name_expr = variable_name ? parse_expression(variable_name) : nil
       @alias_name = alias_name

       # optional comma
@@ -109,7 +108,7 @@ module Liquid
       while p.look(:id)
         key = p.consume
         p.consume(:colon)
-        @attributes[key] = parse_expression(p.expression)
+        @attributes[key] = safe_parse_expression(p)
         p.consume?(:comma) # optional comma
       end
     end
diff --git a/lib/liquid/tags/render.rb b/lib/liquid/tags/render.rb
index 89c11063..4f716b24 100644
--- a/lib/liquid/tags/render.rb
+++ b/lib/liquid/tags/render.rb
@@ -88,10 +88,11 @@ module Liquid
     def rigid_parse(markup)
       p = @parse_context.new_parser(markup)

-      template_name = rigid_template_name(p)
+      @template_name_expr = parse_expression(rigid_template_name(p), safe: true)
+      @variable_name_expr = nil
       with_or_for = p.id?("for") || p.id?("with") || nil
       if with_or_for
-        variable_name = p.expression
+        @variable_name_expr = safe_parse_expression(p)
       end

       alias_name = nil
@@ -99,8 +100,6 @@ module Liquid
         alias_name = p.consume(:id)
       end

-      @template_name_expr = parse_expression(template_name)
-      @variable_name_expr = variable_name ? parse_expression(variable_name) : nil
       @alias_name = alias_name
       @is_for_loop = (with_or_for == FOR)

@@ -111,7 +110,7 @@ module Liquid
       while p.look(:id)
         key = p.consume
         p.consume(:colon)
-        @attributes[key] = parse_expression(p.expression)
+        @attributes[key] = safe_parse_expression(p)
         p.consume?(:comma) # optional comma
       end
     end
diff --git a/lib/liquid/variable.rb b/lib/liquid/variable.rb
index 20957065..a3623bc5 100644
--- a/lib/liquid/variable.rb
+++ b/lib/liquid/variable.rb
@@ -65,11 +65,11 @@ module Liquid

       return if p.look(:end_of_string)

-      @name = parse_context.parse_expression(p.expression)
+      @name = parse_context.safe_parse_expression(p)
       while p.consume?(:pipe)
         filtername = p.consume(:id)
         filterargs = p.consume?(:colon) ? parse_filterargs(p) : Const::EMPTY_ARRAY
-        @filters << parse_filter_expressions(filtername, filterargs)
+        @filters << parse_filter_expressions(filtername, filterargs, safe: true)
       end
       p.consume(:end_of_string)
     end
@@ -122,15 +122,15 @@ module Liquid

     private

-    def parse_filter_expressions(filter_name, unparsed_args)
+    def parse_filter_expressions(filter_name, unparsed_args, safe: false)
       filter_args  = []
       keyword_args = nil
       unparsed_args.each do |a|
-        if (matches = a.match(JustTagAttributes))
+        if (matches = a.match(JustTagAttributes)) # we'll need to fix this
           keyword_args           ||= {}
-          keyword_args[matches[1]] = parse_context.parse_expression(matches[2])
+          keyword_args[matches[1]] = parse_context.parse_expression(matches[2], safe: false)
         else
-          filter_args << parse_context.parse_expression(a)
+          filter_args << parse_context.parse_expression(a, safe: safe)
         end
       end
       result = [filter_name, filter_args]
2025-10-27 16:33:31 +01:00
Ian Ker-Seymer 1b2b62964e Allow for binary comparison of incompatible strings 2024-01-30 19:03:05 -05:00
Marco Rudilosso 21d6197533 Call to_liquid_value when short circuiting conditions 2023-07-19 15:22:12 +00:00
Guilherme CarreiroandGitHub 9ab688eada Update rubocop-shopify (2.7.0 -> 2.12.0) (#1687) 2023-02-15 08:40:59 +01:00
Thierry Joyal 1d2bee1f60 Condition#evaluate to receive mandatory context argument 2022-03-02 14:35:31 -05:00
Charles-P. Clermont e86fe27259 Fix lint 2021-09-09 11:22:39 -04:00
Michael Go f686c5dec7 use Utils.to_liquid_value on conditionals 2021-06-14 18:19:37 -03:00
Dylan Thacker-SmithandGitHub 10ea6144e0 Add Liquid::ParseContext#parse_expression for liquid-c node disabling (#1333)
We would like to be able to disable liquid-c VM rendering at runtime,
but right now expression parsing is done using Expression.parse, which
isn't aware of the parse context.  That prevents us from conditionally
compiling to VM code based on a parse option.
2020-10-27 11:00:04 -04:00
Dylan Thacker-SmithandGitHub a03f02789b Only use MethodLiteral in condition expressions (#1300) 2020-09-25 11:10:33 -04:00
Alessandro Diogo BrückheimerandMike Angell e83b1e4159 Add ForceEqualSignAlignment to .rubocop.yml (#1190)
* Add ForceEqualSignAlignment to .rubocop.yml

* Revert ForceEqualSignAlignment cop

* Update method alignment

* Undo addition of whitespace to improve readability

* Fix missing alignment
2019-10-21 21:18:48 +10:00
0d26f05bb8 Enabled frozen string literals (#1154)
* Enabled frozen string literals

* Update rubocop config

* Prefer string interpolation in simple cases

Co-Authored-By: Dylan Thacker-Smith <[email protected]>
2019-09-18 13:19:45 +10:00
Mike Angell 799da202df Apply simple rubocop fixes 2019-08-31 21:58:33 +10:00
Stephen Paul Weber 7d13d88258 s/Traversal/ParseTreeVisitor 2018-10-18 09:38:33 -04:00
Stephen Paul Weber c11fc656cf Colocate Traversal classes with classes they traverse
This puts all knowledge of the traversal in the same file, and removes
the need for a CASES registry.
2018-10-18 09:37:48 -04:00
Stephen Paul Weber d789ec4175 Liquid::Traversal
This enables traversal over whole document tree.
2018-10-15 10:11:58 -04:00
Dylan Thacker-SmithandGitHub 8928454e29 Use a loop to evaluate binary comparisions to avoid recursion (#891)
Using recursion allows a malicious template to cause a SystemStackError
2017-05-10 10:41:24 -04:00
Dylan Thacker-SmithandGitHub 2bb3552033 Fix internal liquid error when comparing hash with incompatible type (#849) 2017-01-16 13:13:17 -05:00
Florian Weingarten 4c22cef341 blank and empty as variable names 2015-06-04 12:30:50 -04:00
Dylan Thacker-Smith 8a2947865b Avoid an exception from checking if a string contains a non-string. 2015-06-03 02:21:51 -04:00
Florian Weingarten 3372ca8136 Rubocop 2015-05-14 14:37:18 +00:00
Dylan Thacker-Smith a1a128db19 Refactor Condition so that it takes a parsed expression. 2014-10-18 15:03:40 -04:00
Dylan Thacker-Smith 37260f17ff Use Expression.parse and Context#evaluate in the Condition class. 2014-10-18 14:27:58 -04:00
Florian Weingarten 7196a2d58e Avoid parallel assignments 2014-10-18 13:58:32 +00:00
Bogdan Gusiev 4e9d414fde Fixed condition constains operator with wrong data type
"contains" operator on wrong data type should not cause NoMethodError.
2014-08-18 17:32:29 +03:00
Bogdan Gusiev fa14fd02e7 Raise Liquid::ArugmentError when condition has wrong usage
Condition now raises ::ArgumentError when built wrongly.
This patch make it raise Liquid::ArgumentError instead
to indicate a liquid markup error instead of ruby error.
2014-04-21 16:42:37 +03:00
Florian Weingarten 0a7de51e2b Revert some freezes on non-literals 2014-01-27 14:56:07 -05:00
Florian Weingarten 43ac8d560b Freeze all the things 2014-01-07 12:35:16 -05:00
James MacAulay 11dc18bfdf A better fix for "and"/"or" in strings
(now with less side effects)
2009-09-23 15:44:29 -04:00
James MacAulay f42ce88456 fixed conditions with strings containing "and"/"or" 2009-09-14 15:01:26 -04:00
James MacAulay d1d6febfc1 'contains' operator returns false if either operand is nil 2009-08-19 19:38:31 -04:00
Jakub KuźmaandTobias Lütke 8d27864845 Ruby 1.9.1 bugfixes
Signed-off-by: Tobias Lütke <[email protected]>
2009-04-17 06:33:25 +08:00
Tobias Lütke 7f58cbf82d Merged last set of changes from original SVN location 2008-05-08 11:34:43 -04:00
Tobias Lütke 1d647361e1 Initial github import of liquid 2008-05-08 11:28:13 -04:00