Rework ES2015 module system and add missing features. (#2792)

Co-authored-by: Dániel Bátyai <dbatyai@inf.u-szeged.hu> JerryScript-DCO-1.0-Signed-off-by: Dániel Bátyai dbatyai@inf.u-szeged.hu JerryScript-DCO-1.0-Signed-off-by: Daniel Vince vinced@inf.u-szeged.hu
2019-04-25 14:57:17 +02:00
parent 938e9c7530
commit 37b7645e6a
59 changed files with 2209 additions and 991 deletions
@@ -60,11 +60,6 @@ void
 ecma_finalize (void)
 {
  jmem_unregister_free_unused_memory_callback (ecma_free_unused_memory);
-
-#if ENABLED (JERRY_ES2015_MODULE_SYSTEM)
-  ecma_module_finalize_lex_envs ();
-#endif /* ENABLED (JERRY_ES2015_MODULE_SYSTEM) */
-
  ecma_finalize_global_lex_env ();
  ecma_finalize_builtins ();
  ecma_gc_run (JMEM_FREE_UNUSED_MEMORY_SEVERITY_LOW);
@@ -16,12 +16,125 @@
 #ifndef ECMA_MODULE_H
 #define ECMA_MODULE_H

-#include "js-parser-internal.h"
-
 #if ENABLED (JERRY_ES2015_MODULE_SYSTEM)

-void ecma_module_load_modules (parser_context_t *context_p);
+#include "common.h"
+#include "ecma-globals.h"

+#define ECMA_MODULE_MAX_PATH 255u
+
+/**
+ * Imported or exported names, such as "a as b"
+ * Note: See https://www.ecma-international.org/ecma-262/6.0/#table-39
+ *       and https://www.ecma-international.org/ecma-262/6.0/#table-41
+ */
+typedef struct ecma_module_names
+{
+  struct ecma_module_names *next_p; /**< next linked list node */
+  ecma_string_t *imex_name_p;       /**< Import/export name of the item */
+  ecma_string_t *local_name_p;      /**< Local name of the item */
+} ecma_module_names_t;
+
+typedef struct ecma_module ecma_module_t;
+
+/**
+ * Module node to store imports / exports.
+ */
+typedef struct ecma_module_node
+{
+  struct ecma_module_node *next_p;     /**< next linked list node */
+  ecma_module_names_t *module_names_p; /**< names of the requested import/export node */
+  ecma_module_t *module_request_p;     /**< module structure of the requested module */
+} ecma_module_node_t;
+
+/**
+ * Module context containing all import and export nodes.
+ */
+typedef struct ecma_module_context
+{
+  struct ecma_module_context *parent_p;   /**< parent context */
+  ecma_module_node_t *imports_p;          /**< import item of the current context */
+  ecma_module_node_t *local_exports_p;    /**< export item of the current context */
+  ecma_module_node_t *indirect_exports_p; /**< export item of the current context */
+  ecma_module_node_t *star_exports_p;     /**< export item of the current context */
+  ecma_module_t *module_p;                /**< module request */
+} ecma_module_context_t;
+
+/**
+ * An enum identifing the current state of the module
+ */
+typedef enum
+{
+  ECMA_MODULE_STATE_INIT = 0,       /**< module is initialized */
+  ECMA_MODULE_STATE_PARSING = 1,    /**< module is currently being parsed */
+  ECMA_MODULE_STATE_PARSED = 2,     /**< module has been parsed */
+  ECMA_MODULE_STATE_EVALUATING = 3, /**< module is currently being evaluated */
+  ECMA_MODULE_STATE_EVALUATED = 4,  /**< module has been evaluated */
+} ecma_module_state_t;
+
+/**
+ * Module structure storing an instance of a module
+ */
+struct ecma_module
+{
+  struct ecma_module *next_p;         /**< next linked list node */
+  ecma_module_state_t state;          /**< state of the mode */
+  ecma_string_t *path_p;              /**< path of the module */
+  ecma_module_context_t *context_p;   /**< module context of the module */
+  ecma_object_t *compiled_code_p;     /**< compiled code of the module */
+  ecma_object_t *scope_p;             /**< lexica lenvironment of the module */
+  ecma_object_t *namespace_object_p;  /**< namespace import object of the module */
+};
+
+/**
+ *  A record that can be used to store {module, identifier} pairs
+ */
+typedef struct ecma_module_record
+{
+  ecma_module_t *module_p;  /**< module */
+  ecma_string_t *name_p;    /**< identifier name */
+} ecma_module_record_t;
+
+/**
+ *  A list of module records that can be used to identify circular imports during resolution
+ */
+typedef struct ecma_module_resolve_set
+{
+  struct ecma_module_resolve_set *next_p; /**< next in linked list */
+  ecma_module_record_t record;            /**< module record */
+} ecma_module_resolve_set_t;
+
+/**
+ * A list that is used like a stack to drive the resolution process, instead of recursion.
+ */
+typedef struct ecma_module_resolve_stack
+{
+  struct ecma_module_resolve_stack *next_p; /**< next in linked list */
+  ecma_module_t *module_p;                  /**< module request */
+  ecma_string_t *export_name_p;             /**< export identifier name */
+  bool resolving;                           /**< flag storing wether the current frame started resolving */
+} ecma_module_resolve_stack_t;
+
+bool ecma_module_resolve_set_insert (ecma_module_resolve_set_t **set_p,
+                                     ecma_module_t *module_p,
+                                     ecma_string_t *export_name_p);
+void ecma_module_resolve_set_cleanup (ecma_module_resolve_set_t *set_p);
+
+void ecma_module_resolve_stack_push (ecma_module_resolve_stack_t **stack_p,
+                                     ecma_module_t *module_p,
+                                     ecma_string_t *export_name_p);
+void ecma_module_resolve_stack_pop (ecma_module_resolve_stack_t **stack_p);
+
+ecma_string_t *ecma_module_create_normalized_path (const uint8_t *char_p,
+                                                   prop_length_t size);
+ecma_module_t *ecma_module_find_or_create_module (ecma_string_t *path_p);
+
+ecma_value_t ecma_module_connect_imports (void);
+ecma_value_t ecma_module_parse_modules (void);
+ecma_value_t ecma_module_check_indirect_exports (void);
+
+void ecma_module_release_module_names (ecma_module_names_t *module_name_p);
+void ecma_module_cleanup (void);
 #endif /* ENABLED (JERRY_ES2015_MODULE_SYSTEM) */

 #endif /* !ECMA_MODULE_H */