Add Jinja2 macro for adding trailing strings.

third_party/WebKit/Source/build/scripts/templates/ComputedStyleBase.h.tmpl

-{% from 'macros.tmpl' import license %}
+{% from 'macros.tmpl' import license, print_if %}
 {{license()}}
 
 #ifndef ComputedStyleBase_h
 #define ComputedStyleBase_h
 
 #include "core/ComputedStyleBaseConstants.h"
 #include "core/CoreExport.h"
 {% for field in fields if field.storage_type_path != None %}
 #include "{{field.storage_type_path}}.h"
 {% endfor %}
 
 {# Returns the default value for the field, converted to fit in the storage container. #}
-{% macro default_value(field) %}
+{% macro default_value(field) -%}

[sashab, 2017/02/19 23:17:03]

What's the dashes for?

[shend, 2017/02/19 23:20:17]

They strip out leading/trailing whitespace so you can write the {% macro %}
stuff on a separate line without introducing excess new lines in the generated
code.

 {# We only support enum fields for now. #}
-static_cast<unsigned>({{field.default_value}}){% endmacro %}
+static_cast<unsigned>({{field.default_value}})
+{%- endmacro %}
 
 namespace blink {
 
 // The generated portion of ComputedStyle. For more info, see the header comment
 // in ComputedStyle.h.
 class CORE_EXPORT ComputedStyleBase {
  public:
   ALWAYS_INLINE ComputedStyleBase() :
   {% for field in fields %}
-      {% set trailing_comma = "," if field != fields[-1] else "" %}
-      {{field.name}}({{default_value(field)}}){{trailing_comma}}
+      {{field.name}}({{default_value(field)}}){{print_if(not loop.last, ',')}}

[sashab, 2017/02/19 23:17:03]

Woah loop.last awesome!!

[shend, 2017/02/19 23:20:17]

\o/

   {% endfor %}
   {}
   ~ComputedStyleBase() {}
 
   ALWAYS_INLINE ComputedStyleBase(const ComputedStyleBase& o) :
   {% for field in fields %}
-      {% set trailing_comma = "," if field != fields[-1] else "" %}
-      {{field.name}}(o.{{field.name}}){{trailing_comma}}
+      {{field.name}}(o.{{field.name}}){{print_if(not loop.last, ',')}}
   {% endfor %}
   {}
 
   bool operator==(const ComputedStyleBase& o) const {
     return true &&
     {% for field in fields %}
-        {{field.name}} == o.{{field.name}} &&
+        {{field.name}} == o.{{field.name}}{{print_if(not loop.last, ' &&')}}
     {% endfor %}
-        true;
+        ;
   }
 
   bool operator!=(const ComputedStyleBase& o) const { return !(*this == o); }
 
   inline bool inheritedEqual(const ComputedStyleBase& o) const {
     return true &&
     {% for field in fields if field.is_property and field.is_inherited %}
-        {{field.name}} == o.{{field.name}} &&
+        {{field.name}} == o.{{field.name}}{{print_if(not loop.last, ' &&')}}
     {% endfor %}
-        true;
+        ;
   }
 
   inline bool independentInheritedEqual(const ComputedStyleBase& o) const {
     return true &&
     {% for field in fields if field.is_property and field.is_inherited and field.is_independent %}
-        {{field.name}} == o.{{field.name}} &&
+        {{field.name}} == o.{{field.name}}{{print_if(not loop.last, ' &&')}}
     {% endfor %}
-        true;
+        ;
   }
 
   inline bool nonIndependentInheritedEqual(const ComputedStyleBase& o) const {
     return true &&
     {% for field in fields if field.is_property and field.is_inherited and not field.is_independent %}
-        {{field.name}} == o.{{field.name}} &&
+        {{field.name}} == o.{{field.name}}{{print_if(not loop.last, ' &&')}}
     {% endfor %}
-        true;
+        ;
   }
 
   inline bool nonInheritedEqual(const ComputedStyleBase& o) const {
     return true &&
     {% for field in fields if field.is_property and not field.is_inherited %}
-        {{field.name}} == o.{{field.name}} &&
+        {{field.name}} == o.{{field.name}}{{print_if(not loop.last, ' &&')}}
     {% endfor %}
-        true;
+        ;
   }
 
   void setBitDefaults() {
     {% for field in fields %}
     {{field.resetter_method_name}}();
     {% endfor %}
   }
 
   enum IsAtShadowBoundary {
     AtShadowBoundary,
@@ skipping 23 matching lines @@
  protected:
   // Storage.
   {% for field in fields %}
   unsigned {{field.name}} : {{field.size}}; // {{field.storage_type}}
   {% endfor %}
 };
 
 } // namespace blink
 
 #endif // ComputedStyleBase_h