Expose variable environments via C-API

Author: mgreter

docs/api-function.md

@@ -53,6 +53,15 @@ const char* sass_callee_get_path (Sass_Callee_Entry);
 size_t sass_callee_get_line (Sass_Callee_Entry);
 size_t sass_callee_get_column (Sass_Callee_Entry);
 enum Sass_Callee_Type sass_callee_get_type (Sass_Callee_Entry);
+Sass_Env_Frame sass_callee_get_env (Sass_Callee_Entry);
+
+// Getters and Setters for environments (lexical, local and global)
+union Sass_Value* sass_env_get_lexical (Sass_Env_Frame, const char*);
+void sass_env_set_lexical (Sass_Env_Frame, const char*, union Sass_Value*);
+union Sass_Value* sass_env_get_local (Sass_Env_Frame, const char*);
+void sass_env_set_local (Sass_Env_Frame, const char*, union Sass_Value*);
+union Sass_Value* sass_env_get_global (Sass_Env_Frame, const char*);
+void sass_env_set_global (Sass_Env_Frame, const char*, union Sass_Value*);
 ```
 
 ### More links

include/sass/functions.h

@@ -11,13 +11,16 @@ extern "C" {
 
 
 // Forward declaration
+struct Sass_Env;
 struct Sass_Callee;
 struct Sass_Import;
 struct Sass_Options;
 struct Sass_Compiler;
 struct Sass_Importer;
 struct Sass_Function;
 
+// Typedef helpers for callee lists
+typedef struct Sass_Env (*Sass_Env_Frame);
 // Typedef helpers for callee lists
 typedef struct Sass_Callee (*Sass_Callee_Entry);
 // Typedef helpers for import lists
@@ -81,6 +84,16 @@ ADDAPI const char* ADDCALL sass_callee_get_path (Sass_Callee_Entry);
 ADDAPI size_t ADDCALL sass_callee_get_line (Sass_Callee_Entry);
 ADDAPI size_t ADDCALL sass_callee_get_column (Sass_Callee_Entry);
 ADDAPI enum Sass_Callee_Type ADDCALL sass_callee_get_type (Sass_Callee_Entry);
+ADDAPI Sass_Env_Frame ADDCALL sass_callee_get_env (Sass_Callee_Entry);
+
+// Getters and Setters for environments (lexical, local and global)
+ADDAPI union Sass_Value* ADDCALL sass_env_get_lexical (Sass_Env_Frame, const char*);
+ADDAPI void ADDCALL sass_env_set_lexical (Sass_Env_Frame, const char*, union Sass_Value*);
+ADDAPI union Sass_Value* ADDCALL sass_env_get_local (Sass_Env_Frame, const char*);
+ADDAPI void ADDCALL sass_env_set_local (Sass_Env_Frame, const char*, union Sass_Value*);
+ADDAPI union Sass_Value* ADDCALL sass_env_get_global (Sass_Env_Frame, const char*);
+ADDAPI void ADDCALL sass_env_set_global (Sass_Env_Frame, const char*, union Sass_Value*);
+
 // Getters for import entry
 ADDAPI const char* ADDCALL sass_import_get_imp_path (Sass_Import_Entry);
 ADDAPI const char* ADDCALL sass_import_get_abs_path (Sass_Import_Entry);

src/eval.cpp

@@ -913,7 +913,8 @@ namespace Sass {
         c->pstate().path,
         c->pstate().line + 1,
         c->pstate().column + 1,
-        SASS_CALLEE_FUNCTION
+        SASS_CALLEE_FUNCTION,
+        { env }
       });
 
       // eval the body if user-defined or special, invoke underlying CPP function if native
@@ -953,7 +954,8 @@ namespace Sass {
         c->pstate().path,
         c->pstate().line + 1,
         c->pstate().column + 1,
-        SASS_CALLEE_C_FUNCTION
+        SASS_CALLEE_C_FUNCTION,
+        { env }
       });
 
       To_C to_c;

src/expand.cpp

@@ -712,7 +712,8 @@ namespace Sass {
       c->pstate().path,
       c->pstate().line + 1,
       c->pstate().column + 1,
-      SASS_CALLEE_MIXIN
+      SASS_CALLEE_MIXIN,
+      { env }
     });
 
     Env new_env(def->environment());

src/sass_functions.cpp

@@ -2,6 +2,7 @@
 #include <cstring>
 #include "util.hpp"
 #include "context.hpp"
+#include "values.hpp"
 #include "sass/functions.h"
 #include "sass_functions.hpp"
 
@@ -132,6 +133,30 @@ extern "C" {
   size_t ADDCALL sass_callee_get_line(Sass_Callee_Entry entry) { return entry->line; }
   size_t ADDCALL sass_callee_get_column(Sass_Callee_Entry entry) { return entry->column; }
   enum Sass_Callee_Type ADDCALL sass_callee_get_type(Sass_Callee_Entry entry) { return entry->type; }
+  Sass_Env_Frame ADDCALL sass_callee_get_env (Sass_Callee_Entry entry) { return &entry->env; }
+
+  // Getters and Setters for environments (lexical, local and global)
+  union Sass_Value* ADDCALL sass_env_get_lexical (Sass_Env_Frame env, const char* name) {
+    Expression_Ptr ex = SASS_MEMORY_CAST(Expression, (*env->frame)[name]);
+    return ex != NULL ? ast_node_to_sass_value(ex) : NULL;
+  }
+  void ADDCALL sass_env_set_lexical (Sass_Env_Frame env, const char* name, union Sass_Value* val) {
+    (*env->frame)[name] = sass_value_to_ast_node(val);
+  }
+  union Sass_Value* ADDCALL sass_env_get_local (Sass_Env_Frame env, const char* name) {
+    Expression_Ptr ex = SASS_MEMORY_CAST(Expression, env->frame->get_local(name));
+    return ex != NULL ? ast_node_to_sass_value(ex) : NULL;
+  }
+  void ADDCALL sass_env_set_local (Sass_Env_Frame env, const char* name, union Sass_Value* val) {
+    env->frame->set_local(name, sass_value_to_ast_node(val));
+  }
+  union Sass_Value* ADDCALL sass_env_get_global (Sass_Env_Frame env, const char* name) {
+    Expression_Ptr ex = SASS_MEMORY_CAST(Expression, env->frame->get_global(name));
+    return ex != NULL ? ast_node_to_sass_value(ex) : NULL;
+  }
+  void ADDCALL sass_env_set_global (Sass_Env_Frame env, const char* name, union Sass_Value* val) {
+    env->frame->set_global(name, sass_value_to_ast_node(val));
+  }
 
   // Getter for import entry
   const char* ADDCALL sass_import_get_imp_path(Sass_Import_Entry entry) { return entry->imp_path; }

src/sass_functions.hpp

@@ -2,6 +2,8 @@
 #define SASS_SASS_FUNCTIONS_H
 
 #include "sass.h"
+#include "environment.hpp"
+#include "functions.hpp"
 
 // Struct to hold custom function callback
 struct Sass_Function {
@@ -22,13 +24,20 @@ struct Sass_Import {
   size_t column;
 };
 
+// External environments
+struct Sass_Env {
+  // links to parent frames
+  Sass::Env* frame;
+};
+
 // External call entry
 struct Sass_Callee {
   const char* name;
   const char* path;
   size_t line;
   size_t column;
   enum Sass_Callee_Type type;
+  struct Sass_Env env;
 };
 
 // Struct to hold importer callback