Issue pegjs#45 (template rules): Add precheck pass for completes crea…

…ting AST and default handling for new AST nodes.

lib/compiler.js

@@ -18,6 +18,9 @@ var compiler = {
    * |PEG.GrammarError|.
    */
   passes: {
+    precheck: {
+      ruleRef2ParamRef:    require("./compiler/passes/rule-ref2param-ref")
+    },
     check: {
       reportMissingRules:  require("./compiler/passes/report-missing-rules"),
       reportLeftRecursion: require("./compiler/passes/report-left-recursion"),

lib/compiler/passes/rule-ref2param-ref.js

@@ -0,0 +1,21 @@
+var arrays  = require("../../utils/arrays"),
+    visitor = require("../visitor");
+
+function ruleRef2ParamRef(ast) {
+  var convert = visitor.build({
+    rule: function(node) {
+      convert(node.expression, node);
+    },
+
+    rule_ref: function(node, ownerRule) {
+      // This is template parameter reference
+      if (arrays.contains(ownerRule.params, node.name)) {
+        node.type = 'param_ref';
+      }
+    }
+  });
+
+  convert(ast);
+}
+
+module.exports = ruleRef2ParamRef;

lib/compiler/visitor.js

@@ -56,7 +56,9 @@ var visitor = {
           one_or_more:  visitExpression,
           semantic_and: visitNop,
           semantic_not: visitNop,
-          rule_ref:     visitNop,
+          rule_ref:     visitChildren("args"),
+          arg:          visitExpression,
+          param_ref:    visitNop,
           literal:      visitNop,
           "class":      visitNop,
           any:          visitNop

package.json

@@ -28,6 +28,7 @@
     "lib/compiler/passes/report-left-recursion.js",
     "lib/compiler/passes/report-infinite-loops.js",
     "lib/compiler/passes/report-missing-rules.js",
+    "lib/compiler/passes/rule-ref2param-ref.js",
     "lib/grammar-error.js",
     "lib/parser.js",
     "lib/peg.js",

spec/unit/compiler/passes/helpers.js

@@ -63,8 +63,12 @@ beforeEach(function() {
 
     toReportError: function(grammar, details) {
       var ast = PEG.parser.parse(grammar);
+      var pass = PEG.compiler.passes.precheck.ruleRef2ParamRef;
 
       try {
+        // Precheck passes logically parse phase, but cann't be done in parser itself
+        pass(ast, {});
+
         this.actual(ast);
 
         this.message = function() {