Adding better error reporting on unmatched brackets -- you will now get notification of what was expected in most cases

git-svn-id: https://reductivelabs.com/svn/puppet/trunk@2531 980ebf18-57e1-0310-9a29-db15c13687c0

5 files changed, 62 insertions, 2 deletions

diff --git a/CHANGELOG b/CHANGELOG
index b97acb323..648587401 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,5 @@
+    Added better error reporting on unmatched brackets.
+
     Moved puppetd and puppetmasterd to sbin in svn and fixed install.rb
     to copy them into sbin on the local system appropriately.  (#323)
 
diff --git a/lib/puppet/parser/grammar.ra b/lib/puppet/parser/grammar.ra
index c8130ccf0..2d09c9671 100644
--- a/lib/puppet/parser/grammar.ra
+++ b/lib/puppet/parser/grammar.ra
@@ -655,6 +655,9 @@ end
 
 # Raise a Parse error.
 def error(message)
+    if brace = @lexer.expected
+        message += "; expected '%s'"
+    end
     except = Puppet::ParseError.new(message)
     except.line = @lexer.line
     if @lexer.file
@@ -758,6 +761,10 @@ def on_error(token,value,stack)
     #    [@lexer.line,@lexer.last]
     error = "Syntax error at '%s'" % [value]
 
+    if brace = @lexer.expected
+        error += "; expected '%s'" % brace
+    end
+
     except = Puppet::ParseError.new(error)
     except.line = @lexer.line
     if @lexer.file
diff --git a/lib/puppet/parser/lexer.rb b/lib/puppet/parser/lexer.rb
index 9fc1f9a38..daa75f236 100644
--- a/lib/puppet/parser/lexer.rb
+++ b/lib/puppet/parser/lexer.rb
@@ -54,6 +54,16 @@ module Puppet
                 %r{\$(\w*::)*\w+} => :VARIABLE
             }
 
+            @@pairs = {
+                "{" => "}",
+                "(" => ")",
+                "[" => "]",
+                "<|" => "|>",
+                "<<|" => "|>>"
+            }
+
+            @@reverse_pairs = @@pairs.inject({}) { |hash, pair| hash[pair[1]] = pair[0]; hash }
+
             @@keywords = {
                 "case" => :CASE,
                 "class" => :CLASS,
@@ -76,6 +86,20 @@ module Puppet
                 initvars
             end
 
+            def expected
+                if @expected.empty?
+                    nil
+                else
+                    token = @expected[-1]
+                    @@tokens.each do |value, name|
+                        if token == name
+                            return value
+                        end
+                    end
+                    return token
+                end
+            end
+
             # scan the whole file
             # basically just used for testing
             def fullscan
@@ -130,6 +154,8 @@ module Puppet
 
                 @namestack = []
                 @indefine = false
+
+                @expected = []
             end
 
             # Go up one in the namespace.
@@ -247,6 +273,12 @@ module Puppet
                         value = value.sub(/^\$/, '')
                     end
 
+                    if match = @@pairs[value] and ptoken != :DQUOTE and ptoken != :SQUOTE
+                        @expected << match
+                    elsif exp = @expected[-1] and exp == value and ptoken != :DQUOTE and ptoken != :SQUOTE
+                        @expected.pop
+                    end
+
                     yield [ptoken, value]
 
                     if @lasttoken == :CLASS
diff --git a/lib/puppet/parser/parser.rb b/lib/puppet/parser/parser.rb
index 236bd390f..e52d53faa 100644
--- a/lib/puppet/parser/parser.rb
+++ b/lib/puppet/parser/parser.rb
@@ -29,7 +29,7 @@ module Puppet
 
     class Parser < Racc::Parser
 
-module_eval <<'..end grammar.ra modeval..id3bb0c917f5', 'grammar.ra', 608
+module_eval <<'..end grammar.ra modeval..idec1116a64f', 'grammar.ra', 608
 require 'puppet/parser/functions'
 
 attr_reader :file, :interp
@@ -80,6 +80,9 @@ end
 
 # Raise a Parse error.
 def error(message)
+    if brace = @lexer.expected
+        message += "; expected '%s'"
+    end
     except = Puppet::ParseError.new(message)
     except.line = @lexer.line
     if @lexer.file
@@ -183,6 +186,10 @@ def on_error(token,value,stack)
     #    [@lexer.line,@lexer.last]
     error = "Syntax error at '%s'" % [value]
 
+    if brace = @lexer.expected
+        error += "; expected '%s'" % brace
+    end
+
     except = Puppet::ParseError.new(error)
     except.line = @lexer.line
     if @lexer.file
@@ -254,7 +261,7 @@ end
 
 # $Id$
 
-..end grammar.ra modeval..id3bb0c917f5
+..end grammar.ra modeval..idec1116a64f
 
 ##### racc 1.4.5 generates ###
 
diff --git a/test/language/lexer.rb b/test/language/lexer.rb
index bb2cc8d66..7b4909fb1 100755
--- a/test/language/lexer.rb
+++ b/test/language/lexer.rb
@@ -242,6 +242,18 @@ class TestLexer < Test::Unit::TestCase
             end
         end
     end
+
+    # Make sure the expected stack works as it should
+    def test_expected
+        @lexer.string = "[a{"
+        expected = @lexer.instance_variable_get("@expected")
+        @lexer.scan {}
+        assert_equal("}", @lexer.expected, "expected value is wrong")
+
+        @lexer.string = "}"
+        @lexer.scan {}
+        assert_equal("]", @lexer.expected, "expected value is wrong after pop")
+    end
 end
 
 # $Id$