Rename the "node" module format to "commonjs"

Parsers generated in this format use module.exports, so they are not
strictly CommonJS, but this is a common extension and the original name
would be confusing once Node.js implements ES2015 modules.

README.md

@@ -100,8 +100,8 @@ You can tweak the generated parser with several options:
     `peg.generate`
   * `--extra-options-file` — file with additional options (in JSON format) to
     pass to `peg.generate`
-  * `--format` — format of the generated parser: `amd`, `globals`, `node`, `umd`
+  * `--format` — format of the generated parser: `amd`, `commonjs`, `globals`,
-    (default: `node`)
+    `umd` (default: `commonjs`)
   * `--optimize` — selects between optimizing the generated parser for parsing
     speed (`speed`) or code size (`size`) (default: `speed`)
   * `--plugin` — makes PEG.js use a specified plugin (can be specified multiple
@@ -142,13 +142,13 @@ object to `peg.generate`. The following options are supported:
     `false`)
   * `dependencies` — parser dependencies, the value is an object which maps
     variables used to access the dependencies in the parser to module IDs used
-    to load them; valid only when `format` is set to `"amd"`, `"node"`, or
+    to load them; valid only when `format` is set to `"amd"`, `"commonjs"`, or
     `"umd"` (default: `{}`)
   * `exportVar` — name of a global variable into which the parser object is
     assigned to when no module loader is detected; valid only when `format` is
     set to `"globals"` or `"umd"` (default: `null`)
-  * `format` — format of the genreated parser (`"amd"`, `"bare"`, `"globals"`,
+  * `format` — format of the genreated parser (`"amd"`, `"bare"`, `"commonjs"`,
-    `"node"`, or `"umd"`); valid only when `output` is set to `"source"`
+    `"globals"`, or `"umd"`); valid only when `output` is set to `"source"`
     (default: `"bare"`)
   * `optimize`— selects between optimizing the generated parser for parsing
     speed (`"speed"`) or code size (`"size"`) (default: `"speed"`)

bin/pegjs

@@ -32,7 +32,7 @@ function printHelp() {
   console.log("      --extra-options-file <file>    file with additional options (in JSON");
   console.log("                                     format) to pass to peg.generate");
   console.log("      --format <format>              format of the generated parser: amd,");
-  console.log("                                     globals, node, umd (default: node)");
+  console.log("                                     commonjs, globals, umd (default: commonjs)");
   console.log("  -h, --help                         print help and exit");
   console.log("  -O, --optimize <goal>              select optimization for speed or size");
   console.log("                                     (default: speed)");
@@ -114,7 +114,7 @@ var options = {
   cache:        false,
   dependencies: {},
   exportVar:    null,
-  format:       "node",
+  format:       "commonjs",
   optimize:     "speed",
   output:       "source",
   plugins:      [],
@@ -186,8 +186,8 @@ while (args.length > 0 && isOption(args[0])) {
       if (args.length === 0) {
         abort("Missing parameter of the --format option.");
       }
-      if (args[0] !== "amd" && args[0] !== "globals" && args[0] !== "node" && args[0] !== "umd") {
+      if (args[0] !== "amd" && args[0] !== "commonjs" && args[0] !== "globals" && args[0] !== "umd") {
-        abort("Module format must be one of \"amd\", \"globals\", \"node\", and \"umd\".");
+        abort("Module format must be one of \"amd\", \"commonjs\", \"globals\", and \"umd\".");
       }
       options.format = args[0];
       break;
@@ -257,7 +257,7 @@ while (args.length > 0 && isOption(args[0])) {
 }
 
 if (objects.keys(options.dependencies).length > 0) {
-  if (options.format !== "amd" && options.format !== "node" && options.format !== "umd") {
+  if (options.format !== "amd" && options.format !== "commonjs" && options.format !== "umd") {
       abort("Can't use the -d/--dependency option with the \"" + options.format + "\" module format.");
   }
 }

lib/compiler/passes/generate-js.js

@@ -1264,7 +1264,7 @@ function generateJS(ast, options) {
         ].join('\n');
       },
 
-      node: function() {
+      commonjs: function() {
         var parts          = [],
             dependencyVars = objects.keys(options.dependencies),
             requires       = arrays.map(