tcg stands for "TestCase Generator". With tcg, you can write testcases in a way that is language independent, and generate code for specific language.
Syntax of tcg is simple:
begin <test-id>
input = <input value>
output = <output value>
end
where <test-id> defines the name/id of testcase, <input value> defines the input value, and <output value> defines expected output value.
For example:
begin TestToUpper1
input = "foo"
output = "FOO"
end
begin TestToUpper2
input =
"""
this is a raw string block,
with multiple lines.
"""
output =
"""
THIS IS A RAW STRING BLOCK,
WITH MULTIPLE LINES.
"""
end
begin test_split_word
input = "a long long sentence."
output = {"a", "long", "long", "sentence", "."}
end
begin test_map
input = "a:1, b:2"
output = {
"a": 1,
"b": 2,
}
end
By scanning previous testcases definition, tcg can generate code for C++ googletest framework:
// example.h
namespace tcg {
std::string TestToUpper1Input = "foo";
std::string TestToUpper2Input =
"this is a raw string block,\n"
"with multiple lines.";
...
void CheckTestToUpper1(const std::string &output) {
std::string expected = "FOO";
EXPECTED_EQ(expected, output);
}
void CheckTestToUpper2(const std::string &output) {
std::string expected =
"THIS IS A RAW STRING BLOCK,\n"
"WITH MULTIPLE LINES.";
EXPECTED_EQ("FOO", output);
}
} // namespace tcg
Lexical Rules:
DIGIT [0-9]
ALPHABET [a-zA-Z_]
NON_SPACE [^ \t\r\n\v\f]
DOUBLE_QUOTE \"
TRIBAL_QUOTE \"\"\"
K_BEGIN (?i:begin)
K_END (?i:end)
K_INPUT (?i:input)
K_OUTPUT (?i:output)
K_BOOLEAN_TRUE "true"
K_BOOLEAN_FALSE "false"
K_EQUAL_SIGN "="
K_COMMA ","
K_COLON ":"
K_L_BRACKET "["
K_R_BRACKET "]"
K_L_BRACE "{"
K_R_BRACE "}"
ID {ALPHABET}({ALPHABET}|{DIGIT})*
SHORT_STRING_CHAR [^"\n\\]
LONG_STRING_CHAR [^\\]
ESCAPE_SEQ \\.
SHORT_STRING {DOUBLE_QUOTE}({SHORT_STRING_CHAR}|{ESCAPE_SEQ})*{DOUBLE_QUOTE}
LONG_STRING {TRIBAL_QUOTE}({LONG_STRING_CHAR}|{ESCAPE_SEQ})*{TRIBAL_QUOTE}
NON_ZERO_DIGIT [1-9]
DECIMAL_INTEGER ({NON_ZERO_DIGIT}{DIGIT}*)|"0"
FLOAT_NUMBER {DIGIT}+"."{DIGIT}+
Syntax:
Grammar
0 $accept: testcases $end
1 testcases: testcases single_testcase
2 | single_testcase
3 single_testcase: K_BEGIN ID body K_END
4 body: K_INPUT K_EQUAL_SIGN compound K_OUTPUT K_EQUAL_SIGN compound
5 compound: single_element
6 | list
7 | dict
8 list: K_L_BRACKET elements K_R_BRACKET
9 elements: single_element K_COMMA elements
10 | single_element K_COMMA
11 | single_element
12 dict: K_L_BRACE pairs K_R_BRACE
13 pairs: single_pair K_COMMA pairs
14 | single_pair K_COMMA
15 | single_pair
16 single_pair: single_element K_COLON single_element
17 single_element: boolean
18 | number
19 | string
20 boolean: K_BOOLEAN_TRUE
21 | K_BOOLEAN_FALSE
22 number: DECIMAL_INTEGER
23 | FLOAT_NUMBER
24 string: SHORT_STRING