THRIFT-121. Support arbitrary type annotations

Adds syntax for attaching arbitrary key/value pairs to types.
These annotations can be accessed by individual generators to alter
the code they produce.

This version supports annotations on container types and structures.


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@724954 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/compiler/cpp/src/parse/t_type.h b/compiler/cpp/src/parse/t_type.h
index 09e386f..6f178bd 100644
--- a/compiler/cpp/src/parse/t_type.h
+++ b/compiler/cpp/src/parse/t_type.h
@@ -8,6 +8,7 @@
 #define T_TYPE_H
 
 #include <string>
+#include <map>
 #include <cstring>
 #include "t_doc.h"
 
@@ -114,6 +115,7 @@
     return rv;
   }
 
+  std::map<std::string, std::string> annotations_;
 
  protected:
   t_type() :
@@ -148,4 +150,14 @@
   uint8_t fingerprint_[fingerprint_len];
 };
 
+
+/**
+ * Placeholder struct for returning the key and value of an annotation
+ * during parsing.
+ */
+struct t_annotation {
+  std::string key;
+  std::string val;
+};
+
 #endif
diff --git a/compiler/cpp/src/thrifty.yy b/compiler/cpp/src/thrifty.yy
index e5f1736..f27e9ab 100644
--- a/compiler/cpp/src/thrifty.yy
+++ b/compiler/cpp/src/thrifty.yy
@@ -56,6 +56,7 @@
   t_field*       tfield;
   char*          dtext;
   t_field::e_req ereq;
+  t_annotation*  tannot;
 }
 
 /**
@@ -142,6 +143,7 @@
 
 %type<ttype>     BaseType
 %type<ttype>     ContainerType
+%type<ttype>     SimpleContainerType
 %type<ttype>     MapType
 %type<ttype>     SetType
 %type<ttype>     ListType
@@ -152,6 +154,10 @@
 %type<ttypedef>  Typedef
 %type<ttype>     DefinitionType
 
+%type<ttype>     TypeAnnotations
+%type<ttype>     TypeAnnotationList
+%type<tannot>    TypeAnnotation
+
 %type<tfield>    Field
 %type<iconst>    FieldIdentifier
 %type<ereq>      FieldRequiredness
@@ -658,12 +664,16 @@
     }
 
 Struct:
-  tok_struct tok_identifier XsdAll '{' FieldList '}'
+  tok_struct tok_identifier XsdAll '{' FieldList '}' TypeAnnotations
     {
       pdebug("Struct -> tok_struct tok_identifier { FieldList }");
-      $5->set_name($2);
       $5->set_xsd_all($3);
       $$ = $5;
+      $$->set_name($2);
+      if ($7 != NULL) {
+        $$->annotations_ = $7->annotations_;
+        delete $7;
+      }
       y_field_val = -1;
     }
 
@@ -997,20 +1007,30 @@
       $$ = g_type_double;
     }
 
-ContainerType:
+ContainerType: SimpleContainerType TypeAnnotations
+    {
+      pdebug("ContainerType -> SimpleContainerType TypeAnnotations");
+      $$ = $1;
+      if ($2 != NULL) {
+        $$->annotations_ = $2->annotations_;
+        delete $2;
+      }
+    }
+
+SimpleContainerType:
   MapType
     {
-      pdebug("ContainerType -> MapType");
+      pdebug("SimpleContainerType -> MapType");
       $$ = $1;
     }
 | SetType
     {
-      pdebug("ContainerType -> SetType");
+      pdebug("SimpleContainerType -> SetType");
       $$ = $1;
     }
 | ListType
     {
-      pdebug("ContainerType -> ListType");
+      pdebug("SimpleContainerType -> ListType");
       $$ = $1;
     }
 
@@ -1054,4 +1074,38 @@
       $$ = NULL;
     }
 
+TypeAnnotations:
+  '(' TypeAnnotationList ')'
+    {
+      pdebug("TypeAnnotations -> ( TypeAnnotationList )");
+      $$ = $2;
+    }
+|
+    {
+      $$ = NULL;
+    }
+
+TypeAnnotationList:
+  TypeAnnotationList TypeAnnotation
+    {
+      pdebug("TypeAnnotationList -> TypeAnnotationList , TypeAnnotation");
+      $$ = $1;
+      $$->annotations_[$2->key] = $2->val;
+      delete $2;
+    }
+|
+    {
+      /* Just use a dummy structure to hold the annotations. */
+      $$ = new t_struct(g_program);
+    }
+
+TypeAnnotation:
+  tok_identifier '=' tok_literal CommaOrSemicolonOptional
+    {
+      pdebug("TypeAnnotation -> tok_identifier = tok_literal");
+      $$ = new t_annotation;
+      $$->key = $1;
+      $$->val = $3;
+    }
+
 %%
diff --git a/test/AnnotationTest.thrift b/test/AnnotationTest.thrift
new file mode 100644
index 0000000..64e8d82
--- /dev/null
+++ b/test/AnnotationTest.thrift
@@ -0,0 +1,12 @@
+typedef list<i32> ( cpp.template = "std::list" ) int_linked_list
+
+struct foo {
+  1: i32 bar;
+  2: i32 baz;
+  3: i32 qux;
+  4: i32 bop;
+} (
+  cpp.type = "DenseFoo",
+  python.type = "DenseFoo",
+  java.final = "",
+)