some reorganization

(moved pretty much everything that relates to scope in scope.js, added a
module for NodeJS that can be used with require() and exports everything.)

1 files changed, 49 insertions, 4 deletions

diff --git a/lib/scope.js b/lib/scope.js
index a5719bf3..0ac797e0 100644
--- a/lib/scope.js
+++ b/lib/scope.js
@@ -11,6 +11,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
     var labels = {};
     var tw = new TreeWalker(function(node, descend){
         if (node instanceof AST_Scope) {
+            node.init_scope_vars();
             var save_scope = node.parent_scope = scope;
             scope = node;
             descend();
@@ -31,6 +32,9 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
             delete labels[l.name];
             return true;        // no descend again
         }
+        if (node instanceof AST_SymbolDeclaration) {
+            node.init_scope_vars();
+        }
         if (node instanceof AST_SymbolLambda) {
             scope.def_function(node);
         }
@@ -65,15 +69,27 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
     });
     this.walk(tw);
 
-    // pass 2: find back references and eval/with
-    var tw = new TreeWalker(function(node){
+    // pass 2: find back references and eval
+    var func = null;
+    var tw = new TreeWalker(function(node, descend){
+        if (node instanceof AST_Lambda) {
+            var prev_func = func;
+            func = node;
+            descend();
+            func = prev_func;
+            return true;
+        }
         if (node instanceof AST_SymbolRef) {
             var sym = node.scope.find_variable(node);
             node.reference(sym);
             if (!sym) {
                 if (node.name == "eval") {
-                    for (var s = node.scope; s; s = s.parent_scope)
-                        s.uses_eval = true;
+                    for (var s = node.scope;
+                         s && !s.uses_eval;
+                         s = s.parent_scope) s.uses_eval = true;
+                }
+                if (node.name == "arguments") {
+                    func.uses_arguments = true;
                 }
             }
         }
@@ -81,11 +97,31 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
     this.walk(tw);
 });
 
+AST_Scope.DEFMETHOD("init_scope_vars", function(){
+    this.variables = {};      // map name to AST_SymbolVar (variables defined in this scope; includes functions)
+    this.functions = {};      // map name to AST_SymbolDefun (functions defined in this scope)
+    this.uses_with = false;   // will be set to true if this or some nested scope uses the `with` statement
+    this.uses_eval = false;   // will be set to true if this or nested scope uses the global `eval`
+    this.parent_scope = null; // the parent scope
+    this.enclosed = [];       // a list of variables from this or outer scope(s) that are referenced from this or inner scopes
+    this.cname = -1;          // the current index for mangling functions/variables
+});
+
+AST_Lambda.DEFMETHOD("init_scope_vars", function(){
+    AST_Scope.prototype.init_scope_vars.call(this);
+    this.uses_arguments = false;
+});
+
+AST_SymbolDeclaration.DEFMETHOD("init_scope_vars", function(){
+    this.references = [];
+});
+
 AST_Toplevel.DEFMETHOD("scope_warnings", function(options){
     options = defaults(options, {
         undeclared       : false, // this makes a lot of noise
         unreferenced     : true,
         assign_to_global : true,
+        func_arguments   : true,
         eval             : true
     });
     var tw = new TreeWalker(function(node){
@@ -132,6 +168,15 @@ AST_Toplevel.DEFMETHOD("scope_warnings", function(options){
                 col: node.start.col
             });
         }
+        if (options.func_arguments
+            && node instanceof AST_Lambda
+            && node.uses_arguments) {
+            AST_Node.warn("arguments used in function {name} [{line},{col}]", {
+                name: node.name ? node.name.name : "anonymous",
+                line: node.start.line,
+                col: node.start.col
+            });
+        }
     });
     this.walk(tw);
 });