Backport racc-1.4.15 from upstream.

1 files changed, 211 insertions, 0 deletions

diff --git a/lib/racc/logfilegenerator.rb b/lib/racc/logfilegenerator.rb
new file mode 100644
index 0000000000..b95b1afaa2
--- /dev/null
+++ b/lib/racc/logfilegenerator.rb
@@ -0,0 +1,211 @@
+#
+# $Id: a7e9663605afdda065d305b250a9805e3bd3fa70 $
+#
+# Copyright (c) 1999-2006 Minero Aoki
+#
+# This program is free software.
+# You can distribute/modify this program under the terms of
+# the GNU LGPL, Lesser General Public License version 2.1.
+# For details of the GNU LGPL, see the file "COPYING".
+#
+
+module Racc
+
+  class LogFileGenerator
+
+    def initialize(states, debug_flags = DebugFlags.new)
+      @states = states
+      @grammar = states.grammar
+      @debug_flags = debug_flags
+    end
+
+    def output(out)
+      output_conflict out; out.puts
+      output_useless  out; out.puts
+      output_rule     out; out.puts
+      output_token    out; out.puts
+      output_state    out
+    end
+
+    #
+    # Warnings
+    #
+
+    def output_conflict(out)
+      @states.each do |state|
+        if state.srconf
+          out.printf "state %d contains %d shift/reduce conflicts\n",
+                     state.stateid, state.srconf.size
+        end
+        if state.rrconf
+          out.printf "state %d contains %d reduce/reduce conflicts\n",
+                     state.stateid, state.rrconf.size
+        end
+      end
+    end
+
+    def output_useless(out)
+      @grammar.each do |rl|
+        if rl.useless?
+          out.printf "rule %d (%s) never reduced\n",
+                     rl.ident, rl.target.to_s
+        end
+      end
+      @grammar.each_nonterminal do |t|
+        if t.useless?
+          out.printf "useless nonterminal %s\n", t.to_s
+        end
+      end
+    end
+
+    #
+    # States
+    #
+
+    def output_state(out)
+      out << "--------- State ---------\n"
+
+      showall = @debug_flags.la || @debug_flags.state
+      @states.each do |state|
+        out << "\nstate #{state.ident}\n\n"
+
+        (showall ? state.closure : state.core).each do |ptr|
+          pointer_out(out, ptr) if ptr.rule.ident != 0 or showall
+        end
+        out << "\n"
+
+        action_out out, state
+      end
+    end
+
+    def pointer_out(out, ptr)
+      buf = sprintf("%4d) %s :", ptr.rule.ident, ptr.rule.target.to_s)
+      ptr.rule.symbols.each_with_index do |tok, idx|
+        buf << ' _' if idx == ptr.index
+        buf << ' ' << tok.to_s
+      end
+      buf << ' _' if ptr.reduce?
+      out.puts buf
+    end
+
+    def action_out(f, state)
+      sr = state.srconf && state.srconf.dup
+      rr = state.rrconf && state.rrconf.dup
+      acts = state.action
+      keys = acts.keys
+      keys.sort! {|a,b| a.ident <=> b.ident }
+
+      [ Shift, Reduce, Error, Accept ].each do |klass|
+        keys.delete_if do |tok|
+          act = acts[tok]
+          if act.kind_of?(klass)
+            outact f, tok, act
+            if sr and c = sr.delete(tok)
+              outsrconf f, c
+            end
+            if rr and c = rr.delete(tok)
+              outrrconf f, c
+            end
+
+            true
+          else
+            false
+          end
+        end
+      end
+      sr.each {|tok, c| outsrconf f, c } if sr
+      rr.each {|tok, c| outrrconf f, c } if rr
+
+      act = state.defact
+      if not act.kind_of?(Error) or @debug_flags.any?
+        outact f, '$default', act
+      end
+
+      f.puts
+      state.goto_table.each do |t, st|
+        if t.nonterminal?
+          f.printf "  %-12s  go to state %d\n", t.to_s, st.ident
+        end
+      end
+    end
+
+    def outact(f, t, act)
+      case act
+      when Shift
+        f.printf "  %-12s  shift, and go to state %d\n", 
+                 t.to_s, act.goto_id
+      when Reduce
+        f.printf "  %-12s  reduce using rule %d (%s)\n",
+                 t.to_s, act.ruleid, act.rule.target.to_s
+      when Accept
+        f.printf "  %-12s  accept\n", t.to_s
+      when Error
+        f.printf "  %-12s  error\n", t.to_s
+      else
+        raise "racc: fatal: wrong act for outact: act=#{act}(#{act.class})"
+      end
+    end
+
+    def outsrconf(f, confs)
+      confs.each do |c|
+        r = c.reduce
+        f.printf "  %-12s  [reduce using rule %d (%s)]\n",
+                 c.shift.to_s, r.ident, r.target.to_s
+      end
+    end
+
+    def outrrconf(f, confs)
+      confs.each do |c|
+        r = c.low_prec
+        f.printf "  %-12s  [reduce using rule %d (%s)]\n",
+                 c.token.to_s, r.ident, r.target.to_s
+      end
+    end
+
+    #
+    # Rules
+    #
+
+    def output_rule(out)
+      out.print "-------- Grammar --------\n\n"
+      @grammar.each do |rl|
+        if @debug_flags.any? or rl.ident != 0
+          out.printf "rule %d %s: %s\n",
+                     rl.ident, rl.target.to_s, rl.symbols.join(' ')
+        end
+      end
+    end
+
+    #
+    # Tokens
+    #
+
+    def output_token(out)
+      out.print "------- Symbols -------\n\n"
+
+      out.print "**Nonterminals, with rules where they appear\n\n"
+      @grammar.each_nonterminal do |t|
+        tmp = <<SRC
+  %s (%d)
+    on right: %s
+    on left : %s
+SRC
+        out.printf tmp, t.to_s, t.ident,
+                   symbol_locations(t.locate).join(' '),
+                   symbol_locations(t.heads).join(' ')
+      end
+
+      out.print "\n**Terminals, with rules where they appear\n\n"
+      @grammar.each_terminal do |t|
+        out.printf "  %s (%d) %s\n",
+                   t.to_s, t.ident, symbol_locations(t.locate).join(' ')
+      end
+    end
+
+    def symbol_locations(locs)
+      locs.map {|loc| loc.rule.ident }.reject {|n| n == 0 }.uniq
+    end
+
+  end
+
+end   # module Racc