added mangler and other stuff

lib/ast.js

@@ -44,6 +44,11 @@ var AST_Node = DEFNODE("Node", "start end", {
     }
 }, null);
 
+AST_Node.warn_function = noop;
+AST_Node.warn = function(txt, props) {
+    AST_Node.warn_function(string_template(txt, props));
+};
+
 var AST_Debugger = DEFNODE("Debugger", null, {
     $documentation: "Represents a debugger statement"
 });
@@ -121,6 +126,7 @@ var AST_For = DEFNODE("For", "init condition step", {
             if (this.init) this.init._walk(visitor);
             if (this.condition) this.condition._walk(visitor);
             if (this.step) this.step._walk(visitor);
+            this.body._walk(visitor);
         });
     }
 }, AST_Statement);
@@ -132,6 +138,7 @@ var AST_ForIn = DEFNODE("ForIn", "init name object", {
             if (this.init) this.init._walk(visitor);
             if (this.name) this.name._walk(visitor);
             if (this.object) this.object._walk(visitor);
+            this.body._walk(visitor);
         });
     }
 }, AST_Statement);
@@ -151,12 +158,15 @@ var AST_With = DEFNODE("With", "expression", {
 var AST_Scope = DEFNODE("Scope", null, {
     $documentation: "Base class for all statements introducing a lexical scope",
     initialize: function() {
-        this.labels = {};
+        this.labels = {};         // map name to AST_Label (labels defined in this scope)
-        this.variables = {};
+        this.variables = {};      // map name to AST_SymbolVar (variables defined in this scope; includes functions)
-        this.functions = {};
+        this.functions = {};      // map name to AST_SymbolDefun (functions defined in this scope)
-        this.uses_with = false;
+        this.uses_with = false;   // will be set to true if this or some nested scope uses the `with` statement
-        this.uses_eval = false;
+        this.uses_eval = false;   // will be set to true if this or nested scope uses the global `eval`
-        this.parent_scope = null;
+        this.parent_scope = null; // the parent scope
+        this.enclosed = [];       // a list of variables this or from outer scope(s) that are accessed from this or inner scopes
+        this.cname = -1;          // the current index for mangling functions/variables
+        this.lname = -1;          // the current index for mangling labels
     }
 }, AST_BlockStatement);
 
@@ -496,17 +506,7 @@ var AST_Label = DEFNODE("Label", null, {
 }, AST_SymbolDeclaration);
 
 var AST_SymbolRef = DEFNODE("SymbolRef", "symbol", {
-    $documentation: "Reference to some symbol (not definition/declaration)",
+    $documentation: "Reference to some symbol (not definition/declaration)"
-    reference: function(symbol) {
-        if (symbol) {
-            this.symbol = symbol;
-            symbol.references.push(this);
-            this.global = symbol.scope.parent_scope == null;
-        } else {
-            this.undeclared = true;
-            this.global = true;
-        }
-    }
 }, AST_Symbol);
 
 var AST_LabelRef = DEFNODE("LabelRef", null, {

lib/output.js

@@ -804,12 +804,20 @@ function OutputStream(options) {
     DEFPRINT(AST_Symbol, function(self, output){
         output.print_name(self.name);
     });
+    DEFPRINT(AST_SymbolDeclaration, function(self, output){
+        output.print_name(self.mangled_name || self.name);
+    });
+    DEFPRINT(AST_SymbolRef, function(self, output){
+        var def = self.symbol;
+        if (def) {
+            def.print(output);
+        } else {
+            output.print_name(self.name);
+        }
+    });
     DEFPRINT(AST_This, function(self, output){
         output.print("this");
     });
-    DEFPRINT(AST_Label, function(self, output){
-        output.print_name(self.name);
-    });
     DEFPRINT(AST_Constant, function(self, output){
         output.print(self.getValue());
     });

lib/scope.js

@@ -21,18 +21,20 @@ AST_Scope.DEFMETHOD("figure_out_scope", function(){
                 s.uses_with = true;
             return;
         }
-        if (node instanceof AST_SymbolDeclaration && !scope.parent_scope) {
+        if (node instanceof AST_SymbolLambda) {
-            node.global = true;
-        }
-        if (node instanceof AST_SymbolVar) {
-            scope.def_variable(node);
-        }
-        else if (node instanceof AST_SymbolLambda) {
             scope.def_function(node);
         }
         else if (node instanceof AST_SymbolDefun) {
+            // Careful here, the scope where this should be defined is
+            // the parent scope.  The reason is that we enter a new
+            // scope when we encounter the AST_Defun node (which is
+            // instanceof AST_Scope) but we get to the symbol a bit
+            // later.
             scope.parent_scope.def_function(node);
         }
+        else if (node instanceof AST_SymbolVar) {
+            scope.def_variable(node);
+        }
         else if (node instanceof AST_Label) {
             scope.def_label(node);
         }
@@ -58,19 +60,72 @@ AST_Scope.DEFMETHOD("figure_out_scope", function(){
         }
         else if (node instanceof AST_SymbolRef) {
             var sym = node.scope.find_variable(node);
+            node.reference(sym);
             if (!sym) {
                 if (node.name == "eval") {
                     for (var s = scope; s; s = s.parent_scope)
                         s.uses_eval = true;
                 }
-            } else {
-                node.reference(sym);
             }
         }
     });
     this.walk(tw);
 });
 
+AST_Scope.DEFMETHOD("scope_warnings", function(options){
+    options = defaults(options, {
+        undeclared       : false,
+        assign_to_global : true
+    });
+    var tw = new TreeWalker(function(node){
+        if (options.undeclared
+            && node instanceof AST_SymbolRef
+            && node.undeclared)
+        {
+            // XXX: this also warns about JS standard names,
+            // i.e. Object, Array, parseInt etc.  Should add a list of
+            // exceptions.
+            AST_Node.warn("Undeclared symbol: {name} [{line},{col}]", {
+                name: node.name,
+                line: node.start.line,
+                col: node.start.col
+            });
+        }
+        if (options.assign_to_global
+            && node instanceof AST_Assign
+            && node.left instanceof AST_SymbolRef
+            && (node.left.undeclared
+                || (node.left.symbol.global
+                    && node.left.scope !== node.left.symbol.scope)))
+        {
+            AST_Node.warn("{msg}: {name} [{line},{col}]", {
+                msg: node.left.undeclared ? "Accidental global?" : "Assignment to global",
+                name: node.left.name,
+                line: node.start.line,
+                col: node.start.col
+            });
+        }
+    });
+    this.walk(tw);
+});
+
+AST_SymbolRef.DEFMETHOD("reference", function(symbol) {
+    if (symbol) {
+        this.symbol = symbol;
+        var origin = symbol.scope;
+        symbol.references.push(this);
+        for (var s = this.scope; s; s = s.parent_scope) {
+            push_uniq(s.enclosed, symbol);
+            if (s === origin) break;
+        }
+    } else {
+        this.undeclared = true;
+        for (var s = this.scope; s; s = s.parent_scope) {
+            push_uniq(s.enclosed, this);
+        }
+    }
+});
+
 AST_Scope.DEFMETHOD("find_variable", function(name){
     if (name instanceof AST_Symbol) name = name.name;
     return this.variables[name] ||
@@ -90,6 +145,7 @@ AST_Scope.DEFMETHOD("def_function", function(symbol){
 });
 
 AST_Scope.DEFMETHOD("def_variable", function(symbol){
+    symbol.global = !this.parent_scope;
     this.variables[symbol.name] = symbol;
     delete this.functions[symbol.name];
     symbol.scope = this;
@@ -99,3 +155,52 @@ AST_Scope.DEFMETHOD("def_label", function(symbol){
     this.labels[symbol.name] = symbol;
     symbol.scope = this;
 });
+
+AST_Scope.DEFMETHOD("next_mangled", function(for_label){
+    var ext = this.enclosed, n = ext.length;
+    out: for (;;) {
+        var m = base54(for_label
+                       ? (++this.lname)
+                       : (++this.cname));
+
+        if (!is_identifier(m)) continue; // skip over "do"
+
+        // labels are easy, since they can't be referenced from nested
+        // scopes.  XXX: not sure that will be the case when the `let`
+        // keyword is to be supported.
+        if (for_label) return m;
+
+        // if it's for functions or variables, we must ensure that the
+        // mangled name does not shadow a name from some parent scope
+        // that is referenced in this or in inner scopes.
+        for (var i = n; --i >= 0;) {
+            var sym = ext[i];
+            var name = sym.mangled_name || sym.name;
+            if (m == name) continue out;
+        }
+
+        return m;
+    }
+});
+
+AST_SymbolDeclaration.DEFMETHOD("mangle", function(){
+    if (!this.global)
+        this.mangled_name = this.scope.next_mangled(false);
+});
+
+AST_Label.DEFMETHOD("mangle", function(){
+    this.mangled_name = this.scope.next_mangled(true);
+});
+
+AST_Scope.DEFMETHOD("mangle_names", function(){
+    var tw = new TreeWalker(function(node){
+        // We only need to mangle declarations.  Special logic wired
+        // into the code generator will display the mangled name if
+        // it's present (and for AST_SymbolRef-s it'll use the mangled
+        // name of the AST_SymbolDeclaration that it points to).
+        if (node instanceof AST_SymbolDeclaration) {
+            node.mangle();
+        }
+    });
+    this.walk(tw);
+});

lib/utils.js

@@ -98,7 +98,13 @@ var MAP = (function(){
     return MAP;
 })();
 
-var BASE54_DIGITS = "etnrisouaflchpdvmgybwESxTNCkLAOM_DPHBjFIqRUzWXV$JKQGYZ0516372984";
+// XXX: currently this is optimized for jQuery, though I have the
+// feeling it works well in general for many scripts (well, better
+// than alphabetical order).  It would be nice if we could adapt it to
+// the currently running script.
+// var BASE54_DIGITS = "etnrisouaflchpdvmgybwESxTNCkLAOM_DPHBjFIqRUzWXV$JKQGYZ0516372984";
+
+var BASE54_DIGITS = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_0123456789";
 
 function base54(num) {
     var ret = "", base = 54;
@@ -109,3 +115,14 @@ function base54(num) {
     } while (num > 0);
     return ret;
 };
+
+function push_uniq(array, el) {
+    if (array.indexOf(el) < 0)
+        array.push(el);
+};
+
+function string_template(text, props) {
+    return text.replace(/\{(.+?)\}/g, function(str, p){
+        return props[p];
+    });
+};

tmp/test-node.js

@@ -22,43 +22,58 @@
     load_global("../lib/scope.js");
     load_global("../lib/output.js");
 
+    AST_Node.warn_function = function(txt) {
+        sys.debug(txt);
+    };
+
     ///
 
     var filename = process.argv[2];
-    console.time("parse");
+    var code = fs.readFileSync(filename, "utf8");
-    var ast = parse(fs.readFileSync(filename, "utf8"));
-    console.timeEnd("parse");
 
-    var stream = OutputStream({ beautify: true });
+    var ast = time_it("parse", function() {
-    console.time("figure_out_scope");
+        return parse(code);
-    ast.figure_out_scope();
-    console.timeEnd("figure_out_scope");
-    console.time("generate");
-    ast.print(stream);
-    console.timeEnd("generate");
-    //sys.puts(stream.get());
-
-
-    var w = new TreeWalker(function(node, descend){
-        if (node.start) {
-            console.log(node.TYPE + " [" + node.start.line + ":" + node.start.col + "]");
-        } else {
-            console.log(node.TYPE + " [NO START]");
-        }
-        if (node instanceof AST_Scope) {
-            if (node.uses_eval) console.log("!!! uses eval");
-            if (node.uses_with) console.log("!!! uses with");
-        }
-        if (node instanceof AST_SymbolDeclaration) {
-            console.log("--- declaration " + node.name + (node.global ? " [global]" : ""));
-        }
-        else if (node instanceof AST_SymbolRef) {
-            console.log("--- reference " + node.name + " to " + (node.symbol ? node.symbol.name : "global"));
-            if (node.symbol) {
-                console.log("    declaration at: " + node.symbol.start.line + ":" + node.symbol.start.col);
-            }
-        }
     });
-    ast._walk(w);
+    var stream = OutputStream({ beautify: true });
+    time_it("scope", function(){
+        ast.figure_out_scope();
+    });
+    time_it("mangle", function(){
+        ast.mangle_names();
+    });
+    time_it("generate", function(){
+        ast.print(stream);
+    });
+    sys.puts(stream.get());
+
+    // var w = new TreeWalker(function(node, descend){
+    //     if (node.start) {
+    //         console.log(node.TYPE + " [" + node.start.line + ":" + node.start.col + "]");
+    //     } else {
+    //         console.log(node.TYPE + " [NO START]");
+    //     }
+    //     if (node instanceof AST_Scope) {
+    //         if (node.uses_eval) console.log("!!! uses eval");
+    //         if (node.uses_with) console.log("!!! uses with");
+    //     }
+    //     if (node instanceof AST_SymbolDeclaration) {
+    //         console.log("--- declaration " + node.name + (node.global ? " [global]" : ""));
+    //     }
+    //     else if (node instanceof AST_SymbolRef) {
+    //         console.log("--- reference " + node.name + " to " + (node.symbol ? node.symbol.name : "global"));
+    //         if (node.symbol) {
+    //             console.log("    declaration at: " + node.symbol.start.line + ":" + node.symbol.start.col);
+    //         }
+    //     }
+    // });
+    // ast._walk(w);
+
+    ast.scope_warnings();
+
+    function time_it(name, cont) {
+        var t1 = new Date().getTime();
+        try { return cont(); }
+        finally { sys.debug("// " + name + ": " + ((new Date().getTime() - t1) / 1000).toFixed(3) + " sec."); }
+    };
 
 })();