Merge pull request ruby#441 from ydah/support-rules-option

Add support `--report=rules` option
ydah · Jun 10, 2024 · 9a75458 · 9a75458
2 parents 13140bc + db5b291
commit 9a75458
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Showing 7 changed files with 54 additions and 6 deletions.
diff --git a/lib/lrama/option_parser.rb b/lib/lrama/option_parser.rb
@@ -92,7 +92,7 @@ def parse_by_option_parser(argv)
     end
 
     BISON_REPORTS = %w[states itemsets lookaheads solved counterexamples cex all none]
-    OTHER_REPORTS = %w[terms verbose]
+    OTHER_REPORTS = %w[rules terms verbose]
     NOT_SUPPORTED_REPORTS = %w[cex none]
     VALID_REPORTS = BISON_REPORTS + OTHER_REPORTS - NOT_SUPPORTED_REPORTS
 

diff --git a/lib/lrama/states_reporter.rb b/lib/lrama/states_reporter.rb
@@ -16,9 +16,8 @@ def report(io, **options)
 
     private
 
-    def _report(io, grammar: false, terms: false, states: false, itemsets: false, lookaheads: false, solved: false, counterexamples: false, verbose: false)
-      # TODO: Unused rules
-
+    def _report(io, grammar: false, rules: false, terms: false, states: false, itemsets: false, lookaheads: false, solved: false, counterexamples: false, verbose: false)
+      report_unused_rules(io) if rules
       report_unused_terms(io) if terms
       report_conflicts(io)
       report_grammar(io) if grammar
@@ -49,6 +48,22 @@ def report_unused_terms(io)
       end
     end
 
+    def report_unused_rules(io)
+      used_rules = @states.rules.flat_map(&:rhs)
+
+      unused_rules = @states.rules.map(&:lhs).select do |rule|
+        !used_rules.include?(rule) && rule.token_id != 0
+      end
+
+      unless unused_rules.empty?
+        io << "#{unused_rules.count} Unused Rules\n\n"
+        unused_rules.each_with_index do |rule, index|
+          io << sprintf("%5d %s\n", index, rule.display_name)
+        end
+        io << "\n\n"
+      end
+    end
+
     def report_conflicts(io)
       has_conflict = false
 

diff --git a/spec/fixtures/common/basic.y b/spec/fixtures/common/basic.y
@@ -81,6 +81,9 @@ string_2: string '+'
 string: tSTRING
       ;
 
+unused: tNUMBER
+      ;
+
 %%
 
 // Epilogue
diff --git a/spec/lrama/lexer_spec.rb b/spec/lrama/lexer_spec.rb
@@ -257,6 +257,10 @@
         expect(lexer.next_token).to eq([':', ':'])
         expect(lexer.next_token).to eq([:IDENTIFIER, token_class::Ident.new(s_value: 'tSTRING')])
         expect(lexer.next_token).to eq([';', ';'])
+        expect(lexer.next_token).to eq([:IDENT_COLON, token_class::Ident.new(s_value: 'unused')])
+        expect(lexer.next_token).to eq([':', ':'])
+        expect(lexer.next_token).to eq([:IDENTIFIER, token_class::Ident.new(s_value: 'tNUMBER')])
+        expect(lexer.next_token).to eq([';', ';'])
         expect(lexer.next_token).to eq(['%%', '%%'])
         expect(lexer.next_token).to eq(nil)
       end

diff --git a/spec/lrama/option_parser_spec.rb b/spec/lrama/option_parser_spec.rb
@@ -68,7 +68,7 @@
               -h, --help                       display this help and exit
 
           Valid Reports:
-              states itemsets lookaheads solved counterexamples all terms verbose
+              states itemsets lookaheads solved counterexamples all rules terms verbose
 
           Valid Traces:
               none locations scan parse automaton bitsets closure grammar rules actions resource sets muscles tools m4-early m4 skeleton time ielr cex all

diff --git a/spec/lrama/parser_spec.rb b/spec/lrama/parser_spec.rb
@@ -107,6 +107,7 @@
         Sym.new(id: T::Ident.new(s_value: "string_1"),  alias_name: nil, number: 28, tag: nil,                                 term: false, token_id:  9, nullable: false, precedence: nil, printer: nil),
         Sym.new(id: T::Ident.new(s_value: "string_2"),  alias_name: nil, number: 29, tag: nil,                                 term: false, token_id: 10, nullable: false, precedence: nil, printer: nil),
         Sym.new(id: T::Ident.new(s_value: "string"),    alias_name: nil, number: 30, tag: nil,                                 term: false, token_id: 11, nullable: false, precedence: nil, printer: nil),
+        Sym.new(id: T::Ident.new(s_value: "unused"),    alias_name: nil, number: 31, tag: nil,                                 term: false, token_id: 12, nullable: false, precedence: nil, printer: nil),
       ])
       expect(grammar.types).to eq([Type.new(id: T::Ident.new(s_value: "class"), tag: T::Tag.new(s_value: "<i>"))])
       _rules = grammar.rule_builders.map {|b| [b.lhs, (b.rhs + [b.precedence_sym, b.user_code]).compact, b.line] }
@@ -214,6 +215,13 @@
           ],
           81,
         ],
+        [
+          T::Ident.new(s_value: "unused"),
+          [
+            T::Ident.new(s_value: "tNUMBER")
+          ],
+          84,
+        ],
       ])
       expect(grammar.rules).to eq([
         Rule.new(
@@ -415,6 +423,17 @@
           precedence_sym: grammar.find_symbol_by_s_value!("tSTRING"),
           lineno: 81,
         ),
+        Rule.new(
+          id: 17,
+          lhs: grammar.find_symbol_by_s_value!("unused"),
+          rhs: [
+            grammar.find_symbol_by_s_value!("tNUMBER"),
+          ],
+          token_code: nil,
+          nullable: false,
+          precedence_sym: grammar.find_symbol_by_s_value!("tNUMBER"),
+          lineno: 84,
+        ),
       ])
     end
 

diff --git a/spec/lrama/states_spec.rb b/spec/lrama/states_spec.rb
@@ -15,9 +15,14 @@
       states.compute
 
       io = StringIO.new
-      states.reporter.report(io, grammar: true, terms: true, states: true, itemsets: true, lookaheads: true)
+      states.reporter.report(io, grammar: true, rules: true, terms: true, states: true, itemsets: true, lookaheads: true)
 
       expect(io.string).to eq(<<~STR)
+        1 Unused Rules
+
+            0 unused
+
+
         11 Unused Terms
 
             0 YYerror
@@ -69,6 +74,8 @@
 
            16 string: tSTRING
 
+           17 unused: tNUMBER
+
 
         State 0