From f08fb17b4174d46de8e48a1c19712bede6803743 Mon Sep 17 00:00:00 2001
From: "Glenn Y. Rolland" <glenux@glenux.net>
Date: Fri, 27 Dec 2019 20:30:23 +0100
Subject: [PATCH] Enforce names= definition before parse()

---
 lib/namarara/parser.rb                   | 14 ++++++++++
 spec/example-multi-expr.rb               | 35 ++++++++++++++++++++++++
 spec/example-single-expr.rb              | 21 ++++++++++++++
 spec/namarara/priority_parser_spec.rb    |  4 +++
 spec/namarara/simple_expr_parser_spec.rb | 27 ++++++++++++++++++
 5 files changed, 101 insertions(+)
 create mode 100644 spec/example-multi-expr.rb
 create mode 100644 spec/example-single-expr.rb

diff --git a/lib/namarara/parser.rb b/lib/namarara/parser.rb
index 3ee3944..c3c672e 100755
--- a/lib/namarara/parser.rb
+++ b/lib/namarara/parser.rb
@@ -181,8 +181,22 @@ module Namarara
   # 8< ---- 8< ---- ...
 
   class Parser < Rly::Yacc
+    class MissingNamesError < RuntimeError; end
     attr_writer :names
 
+    # Initialize names hash
+    def initialize(*args)
+      @names = nil
+      super(*args)
+    end
+
+    # Make sure names are filled in
+    def parse(str)
+      raise MissingNamesError if @names.nil?
+
+      super(str)
+    end
+
     # Check if grammar is valid
     def check_grammar(line, tokens)
       grammar = tokens.to_s.split(/=|AND|OR/)
diff --git a/spec/example-multi-expr.rb b/spec/example-multi-expr.rb
new file mode 100644
index 0000000..25889a8
--- /dev/null
+++ b/spec/example-multi-expr.rb
@@ -0,0 +1,35 @@
+
+require 'namarara'
+
+# Initialize Namarara
+namarara = Namarara::Parser.new(Namarara::Lexer.new)
+
+# A set of rules i want to check
+rules = {
+    vulnerable_person: 'is_adult AND is_subordinate',
+    has_constraints: 'is_adult AND has_children',
+    is_child: 'NOT is_adult'
+    # ...
+}
+
+# A set of values i want to inject (values must be expressed as strings)
+namarara.names = {
+    "is_adult" => 'false', 
+    "is_subordinate" => 'true',
+    "has_children" => 'true'
+}
+
+rules.map do |rule|
+    namarara_bet = namarara.parse(rule.expr)
+    result = namarara_bet.compute
+    if result then
+        warnings << "Rule #{rule} is true"
+    end
+end
+
+if not warnings.empty?
+    puts "Warning: you are collectif sensitive personnal data !"
+    puts warnings.join("\n")
+else
+    puts "Perfect! Nothing to say ;-)"
+end
diff --git a/spec/example-single-expr.rb b/spec/example-single-expr.rb
new file mode 100644
index 0000000..60dcb02
--- /dev/null
+++ b/spec/example-single-expr.rb
@@ -0,0 +1,21 @@
+
+require 'namarara'
+
+# Initialize Namarara
+namarara = Namarara::Parser.new(Namarara::Lexer.new)
+
+# Build the binary expression tree (aka BET)
+exp_tree = namarara.parse('this AND (that OR other) AND something_else')
+puts p
+
+# Prepare variables 
+exp_tree.names = {
+  this: 'true',
+  that: 'false',
+  other: 'false',
+  something_else: 'true'
+}
+
+# Compute tree with variables
+result = exp_tree.compute
+puts "#{result} == "
diff --git a/spec/namarara/priority_parser_spec.rb b/spec/namarara/priority_parser_spec.rb
index 9fa5c1b..7d46abd 100644
--- a/spec/namarara/priority_parser_spec.rb
+++ b/spec/namarara/priority_parser_spec.rb
@@ -10,12 +10,14 @@ describe Namarara::Parser do
 
   it 'has to do not before or' do
     line = 'NOT true OR NOT true'
+    parser.names = {}
     token = parser.parse(line)
     assert_equal('( NOT ( bool:true ) ) OR ( NOT ( bool:true ) )', token.to_s)
   end
 
   it 'has to do not before and' do
     line = 'NOT false AND NOT false'
+    parser.names = {}
     token = parser.parse(line)
     assert_equal(
       '( NOT ( bool:false ) ) AND ( NOT ( bool:false ) )',
@@ -25,6 +27,7 @@ describe Namarara::Parser do
 
   it 'has to do and before or' do
     line = 'false OR true AND false'
+    parser.names = {}
     token = parser.parse(line)
     assert_equal(
       '( bool:false ) OR ( ( bool:true ) AND ( bool:false ) )',
@@ -34,6 +37,7 @@ describe Namarara::Parser do
 
   it 'has to do and before or operators' do
     line = 'false OR false AND true OR true'
+    parser.names = {}
     token = parser.parse(line)
     assert_equal(
       '( ( bool:false ) OR ( ( bool:false ) '\
diff --git a/spec/namarara/simple_expr_parser_spec.rb b/spec/namarara/simple_expr_parser_spec.rb
index f7a9eda..753b4c3 100644
--- a/spec/namarara/simple_expr_parser_spec.rb
+++ b/spec/namarara/simple_expr_parser_spec.rb
@@ -17,24 +17,28 @@ describe Namarara::Parser do
 
   it 'has to find true boolean and compute it to expr' do
     line = 'true'
+    parser.names = {}
     token = parser.parse(line)
     assert_equal(true, token.compute)
   end
 
   it 'has to find false boolean and compute it to expr' do
     line = 'false'
+    parser.names = {}
     token = parser.parse(line)
     assert_equal(false, token.compute)
   end
 
   it 'has to find parenthesis expr and compute it to expr' do
     line = '( true )'
+    parser.names = {}
     token = parser.parse(line)
     assert_equal(true, token.compute)
   end
 
   it 'has to apply not on expr' do
     line = 'NOT true'
+    parser.names = {}
     token = parser.parse(line)
     assert_equal(false, token.compute)
   end
@@ -170,4 +174,27 @@ describe Namarara::Parser do
     token = parser.parse(line)
     assert_equal(true, token.compute)
   end
+
+  it 'cannot parse before setting names' do
+    line = 'multi_face_god AND character'
+
+    assert_raises Namarara::Parser::MissingNamesError do
+      token = parser.parse(line)
+      parser.names = {
+        'multi_face_god' => 3,
+        'character' => 1
+      }
+      assert_equal(true, token.compute)
+    end
+  end
+
+  it 'can set names before parsing' do
+    line = 'a_girl_has_no_name AND multi_face_god'
+    parser.names = {
+      'a_girl_has_no_name' => 3,
+      'multi_face_god' => 1
+    }
+    token = parser.parse(line)
+    assert_equal(true, token.compute)
+  end
 end