* ext/psych/lib/psych/syntax_error.rb: Add file, line, offset, and

  message attributes during parse failure.
* ext/psych/parser.c: Update parser to raise exception with correct
  values.
* test/psych/test_exception.rb: corresponding tests.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@33404 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,11 @@
+Wed Oct  5 02:50:27 2011  Aaron Patterson <aaron@tenderlovemaking.com>
+
+	* ext/psych/lib/psych/syntax_error.rb: Add file, line, offset, and
+	  message attributes during parse failure.
+	* ext/psych/parser.c: Update parser to raise exception with correct
+	  values.
+	* test/psych/test_exception.rb: corresponding tests.
+
 Wed Oct  5 01:52:16 2011  Aaron Patterson <aaron@tenderlovemaking.com>
 
 	* ext/psych/parser.c (parse): Use context_mark for indicating error

ext/psych/lib/psych/syntax_error.rb

@@ -0,0 +1,18 @@
+module Psych
+  class SyntaxError < ::SyntaxError
+    attr_reader :file, :line, :column, :offset, :problem, :context
+
+    def initialize file, line, col, offset, problem, context
+      err     = [problem, context].compact.join ' '
+      message = "(%s): %s at line %d column %d" % [file, err, line, col]
+
+      @file    = file
+      @line    = line
+      @column  = col
+      @offset  = offset
+      @problem = problem
+      @context = context
+      super(message)
+    end
+  end
+end

ext/psych/parser.c

@@ -59,6 +59,23 @@ static VALUE allocate(VALUE klass)
     return Data_Wrap_Struct(klass, 0, dealloc, parser);
 }
 
+static VALUE make_exception(yaml_parser_t * parser, VALUE path)
+{
+    VALUE exception;
+    size_t line, column;
+
+    line = parser->context_mark.line + 1;
+    column = parser->context_mark.column + 1;
+
+    return rb_funcall(ePsychSyntaxError, rb_intern("new"), 6,
+	    path,
+	    INT2NUM(line),
+	    INT2NUM(column),
+	    INT2NUM(parser->problem_offset),
+	    parser->problem ? rb_usascii_str_new2(parser->problem) : Qnil,
+	    parser->context ? rb_usascii_str_new2(parser->context) : Qnil);
+}
+
 /*
  * call-seq:
  *    parser.parse(yaml)
@@ -98,21 +115,18 @@ static VALUE parse(VALUE self, VALUE yaml)
 
     while(!done) {
 	if(!yaml_parser_parse(parser, &event)) {
-	    VALUE path;
-	    size_t line   = parser->context_mark.line + 1;
-	    size_t column = parser->context_mark.column + 1;
+	    VALUE path, exception;
 
 	    if(rb_respond_to(yaml, id_path))
 		path = rb_funcall(yaml, id_path, 0);
 	    else
 		path = rb_str_new2("<unknown>");
 
+	    exception = make_exception(parser, path);
 	    yaml_parser_delete(parser);
 	    yaml_parser_initialize(parser);
 
-	    rb_raise(ePsychSyntaxError, "(%s): couldn't parse YAML at line %d column %d",
-		    StringValuePtr(path),
-		    (int)line, (int)column);
+	    rb_exc_raise(exception);
 	}
 
 	switch(event.type) {
@@ -376,6 +390,7 @@ void Init_psych_parser()
     /* UTF-16-BE Encoding with BOM */
     rb_define_const(cPsychParser, "UTF16BE", INT2NUM(YAML_UTF16BE_ENCODING));
 
+    rb_require("psych/syntax_error");
     ePsychSyntaxError = rb_define_class_under(mPsych, "SyntaxError", rb_eSyntaxError);
 
     rb_define_method(cPsychParser, "parse", parse, 1);

test/psych/test_exception.rb

@@ -16,6 +16,21 @@ def setup
       @wups = Wups.new
     end
 
+    def test_attributes
+      e = assert_raises(Psych::SyntaxError) {
+        Psych.load '--- `foo'
+      }
+
+      assert_equal '<unknown>', e.file
+      assert_equal 1, e.line
+      assert_equal 5, e.column
+      # FIXME: offset isn't being set correctly by libyaml
+      # assert_equal 5, e.offset
+
+      assert e.problem
+      assert e.context
+    end
+
     def test_convert
       w = Psych.load(Psych.dump(@wups))
       assert_equal @wups, w