Add a tools/spec_parse.py script.

This makes it possible to run the spec parser in a way which is a bit
more like the other tools that we have (e.g., tools/test.py):

  > tools/spec_parse.py tests/language/callable_test.dart

It still requires the developer to run `make parser` in
tools/spec_parser and hence does not run on a buildbot, but it's one
step forward.

Change-Id: I68ad6cea55bc02dddac21558acec33fc4bfc1981
Reviewed-on: https://dart-review.googlesource.com/9620
Commit-Queue: Erik Ernst <eernst@google.com>
Reviewed-by: Lasse R.H. Nielsen <lrn@google.com>

docs/language/Dart.g

@@ -25,14 +25,22 @@ import java.util.Stack;
 }
 
 @parser::members {
-  public static String filePath = null;
-  public static boolean filePathHasBeenPrinted = true;
+  private String filePath = null;
+  private boolean errorHasOccurred = false;
+
+  /** Parse library, return true if success, false if errors occurred. */
+  public boolean parseLibrary(String filePath) throws RecognitionException {
+    this.filePath = filePath;
+    errorHasOccurred = false;
+    libraryDefinition();
+    return !errorHasOccurred;
+  }
 
   // Grammar debugging friendly output, 'The Definitive ANTLR Reference', p247.
   public String getErrorMessage(RecognitionException e, String[] tokenNames) {
     List stack = getRuleInvocationStack(e, this.getClass().getName());
     String msg = null;
-    if ( e instanceof NoViableAltException ) {
+    if (e instanceof NoViableAltException) {
       NoViableAltException nvae = (NoViableAltException)e;
       msg = "no viable alt; token=" + e.token +
           " (decision=" + nvae.decisionNumber +
@@ -42,9 +50,9 @@ import java.util.Stack;
     else {
       msg = super.getErrorMessage(e, tokenNames);
     }
-    if (!filePathHasBeenPrinted) {
-      filePathHasBeenPrinted = true;
-      System.err.println(">>> Parse error in " + filePath + ":");
+    if (!errorHasOccurred) {
+      errorHasOccurred = true;
+      System.err.println("Parse error in " + filePath + ":");
     }
     return stack + " " + msg;
   }

tests/language_2/language_2_parser.status

@@ -99,10 +99,6 @@ unbalanced_brace_test: Skip # Not yet supported.
 unsigned_right_shift_test: Skip # Not yet supported (but this will be OK!).
 unsupported_operators_test: Skip # Not yet supported.
 variable_declaration_metadata_test: Skip # Not yet supported.
-
-# Tests using generic methods.
-generic_methods_unused_parameter_test: Skip # Not yet supported.
-generic_methods_named_parameters_test: Skip # Not yet supported.
 generic_function_typedef2_test: Skip # Not yet supported.
 
 # Tests using assert in initializer list.

tools/spec_parse.py

@@ -0,0 +1,50 @@
+#!/usr/bin/env python
+#
+# Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE file.
+
+# This script runs the parser which is generated using ANTLR 3 from
+# docs/language/Dart.g. It relies on a certain environment and is hence
+# usable locally where this environment can be obtained, but it may not be
+# possible to run it, e.g., on build bots. The requirements are as follows:
+#
+#   - `make parser` in spec_parser has been executed successfully.
+#   - A suitable JVM is in the PATH and may be executed as 'java'.
+#   - the ANTLR3 jar is available as /usr/share/java/antlr3-runtime.jar.
+
+import os
+import string
+import subprocess
+import sys
+
+import utils
+
+
+def Help(missing):
+  print('Execution of the spec parser failed. Missing: ' + missing)
+  print('Please read the comment near the top of spec_parse.py.\n')
+  sys.exit(1)
+
+
+def Main():
+  args = sys.argv[1:]
+  tools_dir = os.path.dirname(os.path.realpath(__file__))
+  spec_parser_dir = os.path.join(tools_dir, 'spec_parser')
+  spec_parser_file = os.path.join(spec_parser_dir, 'SpecParser.class')
+  antlr_jar = '/usr/share/java/antlr3-runtime.jar'
+  class_path = string.join([spec_parser_dir, antlr_jar], ':')
+  command = ['java', '-cp', class_path, 'SpecParser'] + args
+
+  if not os.path.exists(antlr_jar): Help(antlr_jar)
+  if not os.path.exists(spec_parser_file): Help('"make parser" in spec_parser')
+
+  with utils.CoreDumpArchiver(args):
+    exit_code = subprocess.call(command)
+
+  utils.DiagnoseExitCode(exit_code, command)
+  return exit_code
+
+
+if __name__ == '__main__':
+  sys.exit(Main())

tools/spec_parser/SpecParser.java

@@ -6,27 +6,42 @@ import org.antlr.runtime.*;
 
 /// Class for `main` which will parse files given as command line arguments.
 public class SpecParser {
-  static boolean verbose = false;
+  private static void helpAndExit() {
+    System.err.println("Expected arguments: [--verbose] <file>...");
+    System.exit(1);
+  }
 
   public static void main(String[] args) throws Exception {
-    if (args.length == 0) {
-      System.err.println("Expected a file path as argument.");
-      System.exit(1);
-    }
+    boolean verbose = false;
+    int numberOfFileArguments = 0;
+    int numberOfFailures = 0;
+
+    if (args.length == 0) helpAndExit();
+    numberOfFileArguments = args.length;
     for (int i = 0; i < args.length; i++) {
       String filePath = args[i];
       if (filePath.equals("--verbose")) {
         verbose = true;
+        numberOfFileArguments--;
+        if (numberOfFileArguments == 0) helpAndExit();
         continue;
       }
-      CharStream charStream = new ANTLRFileStream(filePath);
-      DartLexer lexer = new DartLexer(charStream);
-      CommonTokenStream tokens = new CommonTokenStream(lexer);
-      DartParser parser = new DartParser(tokens);
-      DartParser.filePath = filePath;
-      DartParser.filePathHasBeenPrinted = false;
-      if (verbose) System.err.println(">>> Parsing file: " + filePath);
-      parser.libraryDefinition();
+      if (verbose) System.err.println("Parsing file: " + filePath);
+      DartParser parser = new DartParser(new CommonTokenStream(
+          new DartLexer(new ANTLRFileStream(filePath))));
+      if (!parser.parseLibrary(filePath)) numberOfFailures++;
+    }
+    if (numberOfFailures > 0) {
+      System.err.println("Parsed " + numberOfFileArguments + " files, " +
+          numberOfFailures + " failing.");
+      System.exit(1);
+    } else {
+      if (numberOfFileArguments == 1) {
+        System.out.println("Parsed successfully.");
+      } else {
+        System.out.println("Parsed " + numberOfFileArguments +
+            " files successfully.");
+      }
     }
   }
 }