propane/spec/propane/grammar_spec.rb

176 lines
4.3 KiB
Ruby

class Propane
describe Grammar do
it "parses a user grammar" do
input = <<EOF
# Comment line
module a.b;
class Foobar;
token while;
token id
/[a-zA-Z_][a-zA-Z_0-9]*/;
token token_with_code <<
Code for the token
>>
tokenid token_with_no_pattern;
drop /\\s+/;
A -> B <<
a = 42;
>>
B -> C while id;
B -> <<
b = 0;
>>
EOF
grammar = Grammar.new(input)
expect(grammar.classname).to eq "Foobar"
expect(grammar.modulename).to eq "a.b"
o = grammar.tokens.find {|token| token.name == "while"}
expect(o).to_not be_nil
expect(o.line_number).to eq 6
o = grammar.patterns.find {|pattern| pattern.token == o}
expect(o).to_not be_nil
expect(o.pattern).to eq "while"
expect(o.line_number).to eq 6
expect(o.code).to be_nil
o = grammar.tokens.find {|token| token.name == "id"}
expect(o).to_not be_nil
expect(o.line_number).to eq 9
o = grammar.patterns.find {|pattern| pattern.token == o}
expect(o).to_not be_nil
expect(o.pattern).to eq "[a-zA-Z_][a-zA-Z_0-9]*"
expect(o.line_number).to eq 9
expect(o.code).to be_nil
o = grammar.tokens.find {|token| token.name == "token_with_code"}
expect(o).to_not be_nil
expect(o.line_number).to eq 11
o = grammar.patterns.find {|pattern| pattern.token == o}
expect(o).to_not be_nil
expect(o.pattern).to eq "token_with_code"
expect(o.line_number).to eq 11
expect(o.code).to eq "Code for the token\n"
o = grammar.tokens.find {|token| token.name == "token_with_no_pattern"}
expect(o).to_not be_nil
expect(o.line_number).to eq 15
o = grammar.patterns.find {|pattern| pattern.token == o}
expect(o).to be_nil
o = grammar.patterns.find {|pattern| pattern.pattern == "\\s+"}
expect(o).to_not be_nil
expect(o.line_number).to eq 17
expect(o.token).to be_nil
expect(o.code).to be_nil
expect(grammar.rules.size).to eq 3
o = grammar.rules[0]
expect(o.name).to eq "A"
expect(o.components).to eq %w[B]
expect(o.line_number).to eq 19
expect(o.code).to eq " a = 42;\n"
o = grammar.rules[1]
expect(o.name).to eq "B"
expect(o.components).to eq %w[C while id]
expect(o.line_number).to eq 22
expect(o.code).to be_nil
o = grammar.rules[2]
expect(o.name).to eq "B"
expect(o.components).to eq []
expect(o.line_number).to eq 23
expect(o.code).to eq " b = 0;\n"
end
it "parses code segments with semicolons" do
input = <<EOF
token code1 <<
a = b;
return c;
>>
token code2 <<
writeln("Hello there");
>>
tokenid token_with_no_pattern;
EOF
grammar = Grammar.new(input)
o = grammar.tokens.find {|token| token.name == "code1"}
expect(o).to_not be_nil
expect(o.line_number).to eq 1
o = grammar.patterns.find {|pattern| pattern.token == o}
expect(o).to_not be_nil
expect(o.code).to eq " a = b;\n return c;\n"
o = grammar.tokens.find {|token| token.name == "code2"}
expect(o).to_not be_nil
expect(o.line_number).to eq 6
o = grammar.patterns.find {|pattern| pattern.token == o}
expect(o).to_not be_nil
expect(o.code).to eq %[ writeln("Hello there");\n]
end
it "supports mode labels" do
input = <<EOF
token a;
m1: token b;
/foo/ <<
>>
m2: /bar/ <<
>>
drop /q/;
m3: drop /r/;
EOF
grammar = Grammar.new(input)
o = grammar.tokens.find {|token| token.name == "a"}
expect(o).to_not be_nil
o = grammar.patterns.find {|pattern| pattern.token == o}
expect(o).to_not be_nil
expect(o.mode).to be_nil
o = grammar.tokens.find {|token| token.name == "b"}
expect(o).to_not be_nil
o = grammar.patterns.find {|pattern| pattern.token == o}
expect(o).to_not be_nil
expect(o.mode).to eq "m1"
o = grammar.patterns.find {|pattern| pattern.pattern == "foo"}
expect(o).to_not be_nil
expect(o.mode).to be_nil
o = grammar.patterns.find {|pattern| pattern.pattern == "bar"}
expect(o).to_not be_nil
expect(o.mode).to eq "m2"
o = grammar.patterns.find {|pattern| pattern.pattern == "q"}
expect(o).to_not be_nil
expect(o.mode).to be_nil
o = grammar.patterns.find {|pattern| pattern.pattern == "r"}
expect(o).to_not be_nil
expect(o.mode).to eq "m3"
end
end
end