Add 'only-explicit-rules' option to display explicit grammar rules

lib/lrama/grammar/rule.rb

@@ -21,6 +21,14 @@ def ==(other)
       def display_name
         l = lhs.id.s_value
         r = empty_rule? ? "ε" : rhs.map {|r| r.id.s_value }.join(" ")
+        "#{l} -> #{r}"
+      end
+
+      def display_name_without_action
+        l = lhs.id.s_value
+        r = empty_rule? ? "ε" : rhs.map do |r|
+          r.id.s_value if r.first_set.any?
+        end.compact.join(" ")
 
         "#{l} -> #{r}"
       end

lib/lrama/option_parser.rb

@@ -85,6 +85,7 @@ def parse_by_option_parser(argv)
         o.on_tail '    automaton                        display states'
         o.on_tail '    closure                          display states'
         o.on_tail '    rules                            display grammar rules'
+        o.on_tail '    only-explicit-rules              display only explicit grammar rules'
         o.on_tail '    actions                          display grammar rules with actions'
         o.on_tail '    time                             display generation time'
         o.on_tail '    all                              include all the above traces'
@@ -135,8 +136,8 @@ def aliased_report_option(opt)
 
     VALID_TRACES = %w[
       locations scan parse automaton bitsets closure
-      grammar rules actions resource sets muscles
-      tools m4-early m4 skeleton time ielr cex
+      grammar rules only-explicit-rules actions resource
+      sets muscles tools m4-early m4 skeleton time ielr cex
     ].freeze
     NOT_SUPPORTED_TRACES = %w[
       locations scan parse bitsets grammar resource
@@ -146,7 +147,7 @@ def aliased_report_option(opt)
     def validate_trace(trace)
       h = {}
       return h if trace.empty? || trace == ['none']
-      supported = VALID_TRACES - NOT_SUPPORTED_TRACES
+      supported = VALID_TRACES - NOT_SUPPORTED_TRACES - %w[only-explicit-rules]
       if trace == ['all']
         supported.each { |t| h[t.to_sym] = true }
         return h

lib/lrama/trace_reporter.rb

@@ -15,9 +15,10 @@ def report(**options)
 
     private
 
-    # @rbs rules: (bool rules, bool actions, **untyped _) -> void
-    def _report(rules: false, actions: false, **_)
-      report_rules if rules
+    # @rbs rules: (bool rules, bool actions, bool only_explicit_rules, **untyped _) -> void
+    def _report(rules: false, actions: false, only_explicit_rules: false, **_)
+      report_rules if rules && !only_explicit_rules
+      report_only_explicit_rules if only_explicit_rules
       report_actions if actions
     end
 
@@ -27,6 +28,14 @@ def report_rules
       @grammar.rules.each { |rule| puts rule.display_name }
     end
 
+    # @rbs () -> void
+    def report_only_explicit_rules
+      puts "Grammar rules:"
+      @grammar.rules.each do |rule|
+        puts rule.display_name_without_action if rule.lhs.first_set.any?
+      end
+    end
+
     # @rbs () -> void
     def report_actions
       puts "Grammar rules with actions:"

sig/generated/lrama/trace_reporter.rbs

@@ -10,12 +10,15 @@ module Lrama
 
     private
 
-    # @rbs rules: (bool rules, bool actions, **untyped _) -> void
-    def _report: (?rules: untyped, ?actions: untyped, **untyped _) -> untyped
+    # @rbs rules: (bool rules, bool actions, bool only_explicit_rules, **untyped _) -> void
+    def _report: (?rules: untyped, ?actions: untyped, ?only_explicit_rules: untyped, **untyped _) -> untyped
 
     # @rbs () -> void
     def report_rules: () -> void
 
+    # @rbs () -> void
+    def report_only_explicit_rules: () -> void
+
     # @rbs () -> void
     def report_actions: () -> void
   end

spec/lrama/option_parser_spec.rb

@@ -85,6 +85,7 @@
               automaton                        display states
               closure                          display states
               rules                            display grammar rules
+              only-explicit-rules              display only explicit grammar rules
               actions                          display grammar rules with actions
               time                             display generation time
               all                              include all the above traces

spec/lrama/trace_reporter_spec.rb

@@ -0,0 +1,102 @@
+# frozen_string_literal: true
+
+RSpec.describe Lrama::TraceReporter do
+  describe "#report" do
+    let(:path) { "common/basic.y" }
+    let(:y) { File.read(fixture_path(path)) }
+    let(:grammar) do
+      grammar = Lrama::Parser.new(y, path).parse
+      grammar.prepare
+      grammar.validate!
+      grammar
+    end
+
+    context "when rules: true and only_explicit_rules: false" do
+      it "prints the all rules" do
+        expect do
+          described_class.new(grammar).report(rules: true, only_explicit_rules: false)
+        end.to output(<<~RULES).to_stdout
+          Grammar rules:
+          $accept -> program EOI
+          program -> class
+          program -> '+' strings_1
+          program -> '-' strings_2
+          class -> keyword_class tSTRING keyword_end
+          $@1 -> ε
+          $@2 -> ε
+          class -> keyword_class $@1 tSTRING '!' keyword_end $@2
+          $@3 -> ε
+          $@4 -> ε
+          class -> keyword_class $@3 tSTRING '?' keyword_end $@4
+          strings_1 -> string_1
+          strings_2 -> string_1
+          strings_2 -> string_2
+          string_1 -> string
+          string_2 -> string '+'
+          string -> tSTRING
+          unused -> tNUMBER
+        RULES
+      end
+    end
+
+    context "when rules: true and only_explicit_rules: true" do
+      it "prints the only explicit rules" do
+        expect do
+          described_class.new(grammar).report(rules: true, only_explicit_rules: true)
+        end.to output(<<~RULES).to_stdout
+          Grammar rules:
+          $accept -> program EOI
+          program -> class
+          program -> '+' strings_1
+          program -> '-' strings_2
+          class -> keyword_class tSTRING keyword_end
+          class -> keyword_class tSTRING '!' keyword_end
+          class -> keyword_class tSTRING '?' keyword_end
+          strings_1 -> string_1
+          strings_2 -> string_1
+          strings_2 -> string_2
+          string_1 -> string
+          string_2 -> string '+'
+          string -> tSTRING
+          unused -> tNUMBER
+        RULES
+      end
+    end
+
+    context "when actions: true" do
+      it "prints the actions" do
+        expect do
+          described_class.new(grammar).report(actions: true)
+        end.to output(<<~RULES).to_stdout
+          Grammar rules with actions:
+          $accept -> program EOI {}
+          program -> class {}
+          program -> '+' strings_1 {}
+          program -> '-' strings_2 {}
+          class -> keyword_class tSTRING keyword_end { code 1 }
+          $@1 -> ε { code 2 }
+          $@2 -> ε { code 3 }
+          class -> keyword_class $@1 tSTRING '!' keyword_end $@2 {}
+          $@3 -> ε { code 4 }
+          $@4 -> ε { code 5 }
+          class -> keyword_class $@3 tSTRING '?' keyword_end $@4 {}
+          strings_1 -> string_1 {}
+          strings_2 -> string_1 {}
+          strings_2 -> string_2 {}
+          string_1 -> string {}
+          string_2 -> string '+' {}
+          string -> tSTRING {}
+          unused -> tNUMBER {}
+        RULES
+      end
+    end
+
+    context 'when empty options' do
+      it 'does not print anything' do
+        expect do
+          described_class.new(grammar).report
+        end.to_not output.to_stdout
+      end
+    end
+  end
+end