Ensure custom template objects always raise UnknownVariable exception…

…s when attributes cannot be resolved

spec/marten/template/concerns/can_define_template_attributes_spec.cr

@@ -6,7 +6,13 @@ describe Marten::Template::CanDefineTemplateAttributes do
       test = Marten::Template::CanDefineTemplateAttributesSpec::Test.new
       test.resolve_template_attribute("foo").should eq "foo"
       test.resolve_template_attribute("bar").should eq "bar"
-      test.resolve_template_attribute("xyz").should be_nil
+    end
+
+    it "raises a Marten::Template::Errors::UnknownVariable exception when the attribute is not defined" do
+      test = Marten::Template::CanDefineTemplateAttributesSpec::Test.new
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        test.resolve_template_attribute("xyz")
+      end
     end
   end
 end

spec/marten/template/ext/marten/db/fields/file/file_spec.cr

@@ -39,5 +39,14 @@ describe Marten::DB::Field::File::File do
 
       file.resolve_template_attribute("url").should eq field.storage.url("css/app.css")
     end
+
+    it "raises as expected if the specified attribute is not supported" do
+      field = Marten::DB::Field::File.new("my_field")
+      file = Marten::DB::Field::File::File.new(field, "path/to/file.txt")
+
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        file.resolve_template_attribute("unknown_attribute")
+      end
+    end
   end
 end

spec/marten/template/ext/marten/db/query/page_spec.cr

@@ -145,5 +145,14 @@ describe Marten::DB::Query::Page do
       Marten::DB::Query::Page(Tag).new([tag], 2, paginator).resolve_template_attribute("size").should eq 1
       Marten::DB::Query::Page(Tag).new([] of Tag, 2, paginator).resolve_template_attribute("size").should eq 0
     end
+
+    it "raises as expected if the specified attribute is not supported" do
+      tag = Tag.create!(name: "a_tag", is_active: true)
+      paginator = Tag.all.order(:name).paginator(2)
+
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        Marten::DB::Query::Page(Tag).new([tag], 2, paginator).resolve_template_attribute("unknown")
+      end
+    end
   end
 end

spec/marten/template/ext/marten/db/query/paginator_spec.cr

@@ -15,5 +15,13 @@ describe Marten::DB::Query::Paginator do
 
       paginator.resolve_template_attribute("pages_count").should eq 3
     end
+
+    it "raises as expected if the specified attribute is not supported" do
+      paginator = Tag.all.order(:name).paginator(2)
+
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        paginator.resolve_template_attribute("unknown_attribute")
+      end
+    end
   end
 end

spec/marten/template/ext/marten/db/query/set_spec.cr

@@ -145,5 +145,11 @@ describe Marten::DB::Query::Set do
 
       Tag.all.resolve_template_attribute("size").should eq 2
     end
+
+    it "raises as expected if the specified attribute is not supported" do
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        Tag.all.resolve_template_attribute("unknown")
+      end
+    end
   end
 end

spec/marten/template/ext/marten/http/flash_store_spec.cr

@@ -27,10 +27,12 @@ describe Marten::HTTP::FlashStore do
       flash_store.resolve_template_attribute("alert").should eq "bad"
     end
 
-    it "returns nil if the flash message is not found" do
+    it "raises as expected if the specified attribute is not supported" do
       flash_store = Marten::HTTP::FlashStore.new(flashes: {"foo" => "bar", "alert" => "bad"}, discard: [] of String)
 
-      flash_store.resolve_template_attribute("unknown").should be_nil
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        flash_store.resolve_template_attribute("unknown")
+      end
     end
   end
 end

spec/marten/template/ext/marten/schema/bound_field_spec.cr

@@ -48,11 +48,13 @@ describe Marten::Schema::BoundField do
       bound_field_2.resolve_template_attribute("value").should be_nil
     end
 
-    it "returns nil if the passed attribute name is not found" do
+    it "raises as expected if the passed attribute is not supported" do
       schema = Marten::Schema::BoundFieldExtSpec::TestSchema.new(Marten::HTTP::Params::Data{"foo" => ["hello"]})
       bound_field = Marten::Schema::BoundField.new(schema, schema.class.get_field("foo"))
 
-      bound_field.resolve_template_attribute("unknown").should be_nil
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        bound_field.resolve_template_attribute("unknown")
+      end
     end
   end
 end

spec/marten/template/ext/marten/schema_spec.cr

@@ -17,10 +17,12 @@ describe Marten::Schema do
       errors.should eq schema.errors
     end
 
-    it "returns nil if the passed attribute name is not found" do
+    it "raises as expected if the passed attribute name is not found" do
       schema = Marten::SchemaExtSpec::SimpleSchema.new(Marten::HTTP::Params::Data{"foo" => ["hello"]})
 
-      schema.resolve_template_attribute("unknown").should be_nil
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        schema.resolve_template_attribute("unknown")
+      end
     end
   end
 end

spec/marten/template/object/auto_spec.cr

@@ -7,34 +7,49 @@ describe Marten::Template::Object::Auto do
       obj.resolve_template_attribute("attr").should eq "hello"
     end
 
-    it "allows to resolve a key using the #[]? method as a fallback" do
+    it "allows to resolve a key using the #[] method as a fallback" do
       obj = Marten::Template::Object::AutoSpec::Test.new({"foo" => "bar"})
       obj.resolve_template_attribute("foo").should eq "bar"
     end
 
-    it "does not resolve the value using the #[]? method if a public method is resolved first" do
+    it "resolves values #[] with priority over a method with the same key" do
       obj = Marten::Template::Object::AutoSpec::Test.new({"attr" => "bar"})
-      obj.resolve_template_attribute("attr").should eq "hello"
+      obj.resolve_template_attribute("attr").should eq "bar"
     end
 
     it "does not allow to resolve a method that takes arguments" do
       obj = Marten::Template::Object::AutoSpec::Test.new
-      obj.resolve_template_attribute("with_args").should be_nil
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        obj.resolve_template_attribute("with_args")
+      end
     end
 
     it "does not allow to resolve a method that takes a block" do
       obj = Marten::Template::Object::AutoSpec::Test.new
-      obj.resolve_template_attribute("with_block").should be_nil
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        obj.resolve_template_attribute("with_block")
+      end
     end
 
     it "does not allow to resolve a protected method" do
       obj = Marten::Template::Object::AutoSpec::Test.new
-      obj.resolve_template_attribute("protected_attr").should be_nil
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        obj.resolve_template_attribute("protected_attr")
+      end
     end
 
     it "does not allow to resolve a private method" do
       obj = Marten::Template::Object::AutoSpec::Test.new
-      obj.resolve_template_attribute("private_attr").should be_nil
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        obj.resolve_template_attribute("private_attr")
+      end
+    end
+
+    it "raises a Marten::Template::Errors::UnknownVariable exception if the attribute is not supported" do
+      obj = Marten::Template::Object::AutoSpec::Test.new
+      expect_raises(Marten::Template::Errors::UnknownVariable) do
+        obj.resolve_template_attribute("unknown")
+      end
     end
   end
 end
@@ -46,8 +61,8 @@ module Marten::Template::Object::AutoSpec
     def initialize(@data = {} of String => String)
     end
 
-    def []?(key : String)
-      @data[key]?
+    def [](key : String)
+      @data[key]
     end
 
     def attr

src/marten/template/concerns/can_define_template_attributes.cr

@@ -12,6 +12,8 @@ module Marten
           when {% if name.is_a?(StringLiteral) %}{{ name }}{% else %}{{ name.id.stringify }}{% end %}
             {{ name.id }}
           {% end %}
+          else
+            raise Marten::Template::Errors::UnknownVariable.new
           end
         end
       end

src/marten/template/ext/marten/db/field/file/file.cr

@@ -1,17 +1,5 @@
 class Marten::DB::Field::File::File
   include Marten::Template::Object
 
-  # :nodoc:
-  def resolve_template_attribute(key : ::String)
-    case key
-    when "attached?"
-      attached?
-    when "name"
-      name
-    when "size"
-      size
-    when "url"
-      url
-    end
-  end
+  template_attributes :attached?, :name, :size, :url
 end

src/marten/template/ext/marten/db/query/page.cr

@@ -1,34 +1,6 @@
 class Marten::DB::Query::Page(M)
   include Marten::Template::Object
 
-  def resolve_template_attribute(key : String)
-    case key
-    when "all?"
-      all?
-    when "any?"
-      any?
-    when "count"
-      count
-    when "empty?"
-      empty?
-    when "first?"
-      first?
-    when "next_page?"
-      next_page?
-    when "next_page_number"
-      next_page_number
-    when "none?"
-      none?
-    when "number"
-      number
-    when "one?"
-      one?
-    when "previous_page?"
-      previous_page?
-    when "previous_page_number"
-      previous_page_number
-    when "size"
-      size
-    end
-  end
+  template_attributes :all?, :any?, :count, :empty?, :first?, :next_page?, :next_page_number, :none?, :number, :one?,
+    :previous_page?, :previous_page_number, :size
 end

src/marten/template/ext/marten/db/query/paginator.cr

@@ -1,12 +1,5 @@
 class Marten::DB::Query::Paginator(M)
   include Marten::Template::Object
 
-  def resolve_template_attribute(key : String)
-    case key
-    when "page_size"
-      page_size
-    when "pages_count"
-      pages_count
-    end
-  end
+  template_attributes :page_size, :pages_count
 end

src/marten/template/ext/marten/db/query/set.cr

@@ -1,42 +1,6 @@
 class Marten::DB::Query::Set(M)
   include Marten::Template::Object
 
-  def resolve_template_attribute(key : String)
-    case key
-    when "all"
-      all
-    when "all?"
-      all?
-    when "any?"
-      any?
-    when "count"
-      count
-    when "distinct"
-      distinct
-    when "empty?"
-      empty?
-    when "exists?"
-      exists?
-    when "first"
-      first
-    when "first!"
-      first!
-    when "first?"
-      first?
-    when "last"
-      last
-    when "last!"
-      last!
-    when "none"
-      none
-    when "none?"
-      none?
-    when "one?"
-      one?
-    when "reverse"
-      reverse
-    when "size"
-      size
-    end
-  end
+  template_attributes :all, :all?, :any?, :count, :distinct, :empty?, :exists?, :first, :first!, :first?, :last, :last!,
+    :none, :none?, :one?, :reverse, :size
 end

src/marten/template/ext/marten/http/flash_store.cr

@@ -9,7 +9,9 @@ class Marten::HTTP::FlashStore
     when "size"
       size
     else
-      self[key]?
+      self[key]
     end
+  rescue KeyError
+    raise Marten::Template::Errors::UnknownVariable.new
   end
 end

src/marten/template/ext/marten/schema.cr

@@ -7,7 +7,9 @@ abstract class Marten::Schema
     when "errors"
       errors
     else
-      self[key]?
+      self[key]
     end
+  rescue Marten::Schema::Errors::UnknownField
+    raise Marten::Template::Errors::UnknownVariable.new
   end
 end

src/marten/template/ext/marten/schema/bound_field.cr

@@ -14,6 +14,8 @@ class Marten::Schema::BoundField
       id
     when "value"
       value
+    else
+      raise Marten::Template::Errors::UnknownVariable.new
     end
   end
 end

src/marten/template/object/auto.cr

@@ -12,27 +12,39 @@ module Marten
         # :nodoc:
         def resolve_template_attribute(key : String)
           {% begin %}
-            value = case key
-            {% if !@type.abstract? && !@type.type_vars.any?(&.abstract?) %}
-              {% already_processed = [] of String %}
-              {% for type in [@type] + @type.ancestors %}
-                {% if type.name != "Object" && type.name != "Reference" %}
-                  {% for method in type.methods %}
-                    {% if !already_processed.includes?(method.name.id.stringify) %}
-                      {% if method.visibility == :public && !method.accepts_block? && method.args.empty? %}
-                        when {{ method.name.id.stringify }}
-                          self.{{ method.name.id }}
-                        {% already_processed << method.name.id.stringify %}
+            value = nil
+            looked_up_value = false
+
+            if responds_to?(:[])
+              begin
+                value = self[key]
+                looked_up_value = true
+              rescue KeyError
+                # Do nothing
+              end
+            end
+
+            if !looked_up_value
+              value = case key
+              {% if !@type.abstract? && !@type.type_vars.any?(&.abstract?) %}
+                {% already_processed = [] of String %}
+                {% for type in [@type] + @type.ancestors %}
+                  {% if type.name != "Object" && type.name != "Reference" %}
+                    {% for method in type.methods %}
+                      {% if !already_processed.includes?(method.name.id.stringify) %}
+                        {% if method.visibility == :public && !method.accepts_block? && method.args.empty? %}
+                          when {{ method.name.id.stringify }}
+                            self.{{ method.name.id }}
+                          {% already_processed << method.name.id.stringify %}
+                        {% end %}
                       {% end %}
                     {% end %}
                   {% end %}
                 {% end %}
               {% end %}
-            {% end %}
-            end
-
-            if value.nil? && responds_to?(:[]?)
-              value = self[key]?
+                        else
+                          raise Marten::Template::Errors::UnknownVariable.new
+              end
             end
 
             value