refactor: organize test files

60 files changed, 1969 insertions, 1952 deletions

diff --git a/tests/arithmetic_operators.c b/tests/arithmetic_operators.c
deleted file mode 100644
index e7cfe95..0000000
--- a/tests/arithmetic_operators.c
+++ /dev/null
@@ -1,9 +0,0 @@
-#include <helpers.h>
-
-int main() {
-    ASSERT_EQ(42, 42);
-    ASSERT_EQ(21, 5 + 20 - 4);
-    ASSERT_EQ(26, 2 * 3 + 4 * 5);
-    ASSERT_EQ(197, (((3 + 5) / 2) + (5 * (9 - 6)) * (5 + 6 * 7)) % 256);
-    ASSERT_EQ(30, (-10 + 20 * -3) + 100);
-}
diff --git a/tests/assignment_operators.c b/tests/assignment_operators.c
deleted file mode 100644
index 1edc574..0000000
--- a/tests/assignment_operators.c
+++ /dev/null
@@ -1,64 +0,0 @@
-#include <helpers.h>
-
-int main() {
-    int i = 0;
-    for (; i < 5; i += 1) {
-    }
-    ASSERT_EQ(5, i);
-
-    for (i = 5; i >= 0; i -= 1)
-        ;
-    ASSERT_EQ(-1, i);
-
-    int x = 123;
-    x *= 456;
-    ASSERT_EQ(56088, x);
-
-    int y = 120;
-    y /= 5;
-    ASSERT_EQ(24, y);
-
-    int z = 17;
-    z %= 7;
-    ASSERT_EQ(3, z);
-
-    int a = 0x05;
-    a |= 0x0A;
-    ASSERT_EQ(0x0F, a);
-
-    int b = 0x0F;
-    b &= 0x0A;
-    ASSERT_EQ(0x0A, b);
-
-    int c = 7;
-    c |= 8;
-    ASSERT_EQ(15, c);
-
-    int d = 15;
-    d &= 6;
-    ASSERT_EQ(6, d);
-
-    int e = 0x0F;
-    e ^= 0x05;
-    ASSERT_EQ(0x0A, e);
-
-    int f = 3;
-    f <<= 2;
-    ASSERT_EQ(12, f);
-
-    int g = 16;
-    g >>= 2;
-    ASSERT_EQ(4, g);
-
-    int h = -16;
-    h >>= 2;
-    ASSERT_EQ(-4, h);
-
-    int j = 1;
-    j <<= 4;
-    ASSERT_EQ(16, j);
-
-    int k = 64;
-    k >>= 3;
-    ASSERT_EQ(8, k);
-}
diff --git a/tests/bitwise_operators.c b/tests/bitwise_operators.c
deleted file mode 100644
index e8a5619..0000000
--- a/tests/bitwise_operators.c
+++ /dev/null
@@ -1,38 +0,0 @@
-#include <helpers.h>
-
-int main() {
-    ASSERT_EQ(123, 0 | 123);
-    ASSERT_EQ(460, 12 | 456);
-
-    ASSERT_EQ(8, 1 << 3);
-    ASSERT_EQ(336, 21 << 4);
-    ASSERT_EQ(13, 111 >> 3);
-    ASSERT_EQ(0, 15 >> 14);
-
-    int a = 5;
-    int b = 3;
-    ASSERT_EQ(1, a & b);
-    ASSERT_EQ(7, a | b);
-    ASSERT_EQ(6, a ^ b);
-    ASSERT_EQ(4, 2 + 3 & 4);
-
-    int c = 1 + 2 & 3;
-    int d = 4 & 5 ^ 6;
-    int e = 1 ^ 2 | 3;
-    int f = 0 | 1 & 2;
-    ASSERT_EQ(3, c);
-    ASSERT_EQ(2, d);
-    ASSERT_EQ(3, e);
-    ASSERT_EQ(0, f);
-
-    ASSERT_EQ(-1, ~0);
-    ASSERT_EQ(-2, ~1);
-    ASSERT_EQ(-6, ~5);
-    ASSERT_EQ(0, ~(-1));
-    ASSERT_EQ(5, ~(-6));
-
-    int x = 10;
-    ASSERT_EQ(-11, ~x);
-    ASSERT_EQ(-1, ~(x & 0));
-    ASSERT_EQ(-16, ~(x | 5));
-}
diff --git a/tests/bool_type.c b/tests/bool_type.c
deleted file mode 100644
index 7313410..0000000
--- a/tests/bool_type.c
+++ /dev/null
@@ -1,10 +0,0 @@
-#include <helpers.h>
-
-int main() {
-    bool b1 = true, b0 = false;
-    ASSERT_EQ(1, b1);
-    ASSERT_EQ(0, b0);
-    ASSERT_EQ(1, sizeof(b1));
-    ASSERT_EQ(1, sizeof(b0));
-    ASSERT_EQ(1, sizeof(bool));
-}
diff --git a/tests/cli.sh b/tests/cli.sh
new file mode 100644
index 0000000..fc8a481
--- /dev/null
+++ b/tests/cli.sh
@@ -0,0 +1,79 @@
+# --version
+expected="ducc v0.3.0"
+
+if [[ "$("$ducc" --version)" != "$expected" ]]; then
+    echo "invalid output" >&2
+    exit 1
+fi
+
+# assembly output
+cat > foo.c <<'EOF'
+int main() {}
+EOF
+
+"$ducc" -o bar.s foo.c
+if [[ $? -ne 0 ]]; then
+    exit 1
+fi
+gcc -o a.out bar.s
+./a.out "$@"
+exit_code=$?
+
+if [[ $exit_code -ne 0 ]]; then
+    echo "invalid exit code: $exit_code" >&2
+    exit 1
+fi
+
+# argc/argv
+cat <<'EOF' > expected
+argc = 4
+argv[1] = hoge
+argv[2] = piyo
+argv[3] = fuga
+EOF
+test_diff hoge piyo fuga<<'EOF'
+int printf();
+
+int main(int argc, char** argv) {
+    printf("argc = %d\n", argc);
+    int i;
+    for (i = 1; i < argc; ++i) {
+        printf("argv[%d] = %s\n", i, argv[i]);
+    }
+    return 0;
+}
+EOF
+
+# compile errors
+cat <<'EOF' > expected
+main.c:2: undefined function: f
+EOF
+test_compile_error <<'EOF'
+int main() {
+    f();
+}
+EOF
+
+# TODO: improve error message
+# cat <<'EOF' > expected
+# main.c:1: expected ';' or '{', but got '}'
+# EOF
+cat <<'EOF' > expected
+main.c:1: expected ';', but got '}'
+EOF
+
+test_compile_error <<'EOF'
+int main() }
+EOF
+
+# TODO: improve error message
+# cat <<'EOF' > expected
+# main.c:1: expected ';' or '{', but got '}'
+# EOF
+cat <<'EOF' > expected
+main.c:1: expected ';', but got '123'
+EOF
+
+test_compile_error <<'EOF'
+int main() 123
+EOF
diff --git a/tests/comma_operator.sh b/tests/comma_operator.sh
deleted file mode 100644
index b754cf5..0000000
--- a/tests/comma_operator.sh
+++ /dev/null
@@ -1,36 +0,0 @@
-cat <<'EOF' > expected
-0 0
-1 1
-2 2
-3 3
-4 4
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-int main() {
-    int i = 1000;
-    int j = 1000;
-    for (i = 0, j = 0; i < 5; i++, j++) {
-        printf("%d %d\n", i, j);
-    }
-}
-EOF
-
-cat <<'EOF' > expected
-1 2 3 4
-0 0 5
-EOF
-
-test_diff <<'EOF'
-int printf();
-int x, y, z = 5;
-int main() {
-    int a, b;
-    a = 1, b = 2;
-    int c = 3, d = 4;
-    printf("%d %d %d %d\n", a, b, c, d);
-    printf("%d %d %d\n", x, y, z);
-}
-EOF
diff --git a/tests/command_line_args.sh b/tests/command_line_args.sh
deleted file mode 100644
index 7286815..0000000
--- a/tests/command_line_args.sh
+++ /dev/null
@@ -1,18 +0,0 @@
-cat <<'EOF' > expected
-argc = 4
-argv[1] = hoge
-argv[2] = piyo
-argv[3] = fuga
-EOF
-test_diff hoge piyo fuga<<'EOF'
-int printf();
-
-int main(int argc, char** argv) {
-    printf("argc = %d\n", argc);
-    int i;
-    for (i = 1; i < argc; ++i) {
-        printf("argv[%d] = %s\n", i, argv[i]);
-    }
-    return 0;
-}
-EOF
diff --git a/tests/comments.sh b/tests/comments.sh
deleted file mode 100644
index 1318f93..0000000
--- a/tests/comments.sh
+++ /dev/null
@@ -1,24 +0,0 @@
-cat <<'EOF' > expected
-EOF
-test_diff <<'EOF'
-// TODO: check if the token is at the beginning of line.
-// TODO: check if skipped whitespaces do not contain line breaks.
-int main() {
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-EOF
-
-test_diff <<'EOF'
-/* lorem ipsum */
-/*
-lorem ipsum
-*/
-// /*
-/* /*
- */
-int/**/main() {
-}
-EOF
diff --git a/tests/comparison_operators.c b/tests/comparison_operators.c
deleted file mode 100644
index 7e0600d..0000000
--- a/tests/comparison_operators.c
+++ /dev/null
@@ -1,12 +0,0 @@
-#include <helpers.h>
-
-int main() {
-    ASSERT_EQ(1, 0 == 0);
-    ASSERT_EQ(0, 123 != 123);
-    ASSERT_EQ(1, 123 != 456);
-    ASSERT_EQ(0, 123 == 124);
-    ASSERT_EQ(1, 123 < 567);
-    ASSERT_EQ(1, 123 <= 567);
-    ASSERT_EQ(1, 123 <= 123);
-    ASSERT_EQ(0, 123 < 123);
-}
diff --git a/tests/compile_errors.sh b/tests/compile_errors.sh
deleted file mode 100644
index e99282b..0000000
--- a/tests/compile_errors.sh
+++ /dev/null
@@ -1,32 +0,0 @@
-cat <<'EOF' > expected
-main.c:2: undefined function: f
-EOF
-test_compile_error <<'EOF'
-int main() {
-    f();
-}
-EOF
-
-# TODO: improve error message
-# cat <<'EOF' > expected
-# main.c:1: expected ';' or '{', but got '}'
-# EOF
-cat <<'EOF' > expected
-main.c:1: expected ';', but got '}'
-EOF
-
-test_compile_error <<'EOF'
-int main() }
-EOF
-
-# TODO: improve error message
-# cat <<'EOF' > expected
-# main.c:1: expected ';' or '{', but got '}'
-# EOF
-cat <<'EOF' > expected
-main.c:1: expected ';', but got '123'
-EOF
-
-test_compile_error <<'EOF'
-int main() 123
-EOF
diff --git a/tests/compiler_output.sh b/tests/compiler_output.sh
deleted file mode 100644
index 33c4f17..0000000
--- a/tests/compiler_output.sh
+++ /dev/null
@@ -1,16 +0,0 @@
-cat > foo.c <<'EOF'
-int main() {}
-EOF
-
-"$ducc" -o bar.s foo.c
-if [[ $? -ne 0 ]]; then
-    exit 1
-fi
-gcc -o a.out bar.s
-./a.out "$@"
-exit_code=$?
-
-if [[ $exit_code -ne 0 ]]; then
-    echo "invalid exit code: $exit_code" >&2
-    exit 1
-fi
diff --git a/tests/compiler_version.sh b/tests/compiler_version.sh
deleted file mode 100644
index 76ba104..0000000
--- a/tests/compiler_version.sh
+++ /dev/null
@@ -1,6 +0,0 @@
-expected="ducc v0.3.0"
-
-if [[ "$("$ducc" --version)" != "$expected" ]]; then
-    echo "invalid output" >&2
-    exit 1
-fi
diff --git a/tests/define_macros.sh b/tests/define_macros.sh
deleted file mode 100644
index c92560f..0000000
--- a/tests/define_macros.sh
+++ /dev/null
@@ -1,91 +0,0 @@
-cat <<'EOF' > expected
-EOF
-test_diff <<'EOF'
-#define A 1
-int main() {
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-1,2,3
-EOF
-test_diff <<'EOF'
-int printf();
-
-#define A 1
-#define B 2
-#define C 3
-
-int main() {
-    printf("%d,%d,%d\n", A, B, C);
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-0,0,0,0
-EOF
-test_diff <<'EOF'
-int printf();
-
-#define NULL 0
-#define TK_EOF        0
-#define TY_UNKNOWN 0
-#define AST_UNKNOWN       0
-
-int main() {
-    printf("%d,%d,%d,%d\n", NULL, TK_EOF, TY_UNKNOWN, AST_UNKNOWN);
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-42,123
-EOF
-test_diff <<'EOF'
-int printf();
-
-#define A foo_a
-#define B foo_b
-
-int main() {
-    int foo_a = 42;
-    int foo_b = 123;
-
-    printf("%d,%d\n", A, B);
-
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-123
-EOF
-
-test_diff <<'EOF'
-#define foo() 123
-
-int printf();
-
-int main() {
-    printf("%d\n", foo());
-}
-EOF
-
-cat <<'EOF' > expected
-579
-975
-EOF
-
-test_diff <<'EOF'
-#define foo 123 + 456
-#define bar() 321 + 654
-
-int printf();
-
-int main() {
-    printf("%d\n", foo);
-    printf("%d\n", bar());
-}
-EOF
diff --git a/tests/empty_preprocessor.sh b/tests/empty_preprocessor.sh
index 5a744a8..c9000b3 100644
--- a/tests/empty_preprocessor.sh
+++ b/tests/empty_preprocessor.sh
@@ -1,4 +1,4 @@
-touch expected
+> expected
 test_diff <<'EOF'
 #
 #
diff --git a/tests/enums.sh b/tests/enums.sh
deleted file mode 100644
index 3fc15a0..0000000
--- a/tests/enums.sh
+++ /dev/null
@@ -1,48 +0,0 @@
-cat <<'EOF' > expected
-4
-0,1,2
-EOF
-test_diff <<'EOF'
-int printf();
-
-enum E {
-    A,
-    B,
-    C,
-};
-
-int main() {
-    enum E x = A;
-    printf("%d\n", sizeof(enum E));
-    printf("%d,%d,%d\n", A, B, C);
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-10,11,20,21
-0,5,6,6
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-enum E1 {
-    A = 10,
-    B,
-    C = 20,
-    D,
-};
-
-enum E2 {
-    E,
-    F = 5,
-    G,
-    H = G,
-};
-
-int main() {
-    printf("%d,%d,%d,%d\n", A, B, C, D);
-    printf("%d,%d,%d,%d\n", E, F, G, H);
-}
-EOF
diff --git a/tests/ex_fizzbuzz.sh b/tests/ex_fizzbuzz.sh
deleted file mode 100644
index b7a9e6b..0000000
--- a/tests/ex_fizzbuzz.sh
+++ /dev/null
@@ -1,106 +0,0 @@
-set -e
-
-cat <<'EOF' > expected
-1
-2
-Fizz
-4
-Buzz
-Fizz
-7
-8
-Fizz
-Buzz
-11
-Fizz
-13
-14
-FizzBuzz
-16
-17
-Fizz
-19
-Buzz
-Fizz
-22
-23
-Fizz
-Buzz
-26
-Fizz
-28
-29
-FizzBuzz
-31
-32
-Fizz
-34
-Buzz
-Fizz
-37
-38
-Fizz
-Buzz
-41
-Fizz
-43
-44
-FizzBuzz
-46
-47
-Fizz
-49
-Buzz
-Fizz
-52
-53
-Fizz
-Buzz
-56
-Fizz
-58
-59
-FizzBuzz
-61
-62
-Fizz
-64
-Buzz
-Fizz
-67
-68
-Fizz
-Buzz
-71
-Fizz
-73
-74
-FizzBuzz
-76
-77
-Fizz
-79
-Buzz
-Fizz
-82
-83
-Fizz
-Buzz
-86
-Fizz
-88
-89
-FizzBuzz
-91
-92
-Fizz
-94
-Buzz
-Fizz
-97
-98
-Fizz
-Buzz
-EOF
-
-test_example fizzbuzz
diff --git a/tests/ex_hello.sh b/tests/ex_hello.sh
deleted file mode 100644
index 750c14a..0000000
--- a/tests/ex_hello.sh
+++ /dev/null
@@ -1,7 +0,0 @@
-set -e
-
-cat <<'EOF' > expected
-Hello, World!
-EOF
-
-test_example hello
diff --git a/tests/example_programs.sh b/tests/examples.sh
index 24b3f29..6b15ed8 100644
--- a/tests/example_programs.sh
+++ b/tests/examples.sh
@@ -1,3 +1,117 @@
+# hello
+cat <<'EOF' > expected
+Hello, World!
+EOF
+
+test_example hello
+
+# fizzbuzz
+cat <<'EOF' > expected
+1
+2
+Fizz
+4
+Buzz
+Fizz
+7
+8
+Fizz
+Buzz
+11
+Fizz
+13
+14
+FizzBuzz
+16
+17
+Fizz
+19
+Buzz
+Fizz
+22
+23
+Fizz
+Buzz
+26
+Fizz
+28
+29
+FizzBuzz
+31
+32
+Fizz
+34
+Buzz
+Fizz
+37
+38
+Fizz
+Buzz
+41
+Fizz
+43
+44
+FizzBuzz
+46
+47
+Fizz
+49
+Buzz
+Fizz
+52
+53
+Fizz
+Buzz
+56
+Fizz
+58
+59
+FizzBuzz
+61
+62
+Fizz
+64
+Buzz
+Fizz
+67
+68
+Fizz
+Buzz
+71
+Fizz
+73
+74
+FizzBuzz
+76
+77
+Fizz
+79
+Buzz
+Fizz
+82
+83
+Fizz
+Buzz
+86
+Fizz
+88
+89
+FizzBuzz
+91
+92
+Fizz
+94
+Buzz
+Fizz
+97
+98
+Fizz
+Buzz
+EOF
+
+test_example fizzbuzz
+
+# example programs
 cat <<'EOF' > expected
 1
 2
diff --git a/tests/cast_expressions.sh b/tests/expressions.sh
index b493e04..dadfade 100644
--- a/tests/cast_expressions.sh
+++ b/tests/expressions.sh
@@ -1,3 +1,141 @@
+# logical operators
+cat <<'EOF' > expected
+foo
+EOF
+test_diff <<'EOF'
+int printf();
+
+int foo() {
+    printf("foo\n");
+    return 0;
+}
+
+int bar() {
+    printf("bar\n");
+    return 1;
+}
+
+int main() {
+    if (foo() && bar()) {
+        printf("baz\n");
+    }
+
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+foo
+bar
+baz
+EOF
+test_diff <<'EOF'
+int printf();
+
+int foo() {
+    printf("foo\n");
+    return 0;
+}
+
+int bar() {
+    printf("bar\n");
+    return 1;
+}
+
+int main() {
+    if (foo() || bar()) {
+        printf("baz\n");
+    }
+
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+0
+1
+0
+EOF
+test_diff <<'EOF'
+int printf();
+
+int main() {
+    printf("%d\n", !1);
+    printf("%d\n", !0);
+    printf("%d\n", !23);
+    return 0;
+}
+EOF
+
+# increment/decrement operators
+cat <<'EOF' > expected
+44
+44
+46
+46
+44
+42
+42
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+int main() {
+    int a = 42;
+    ++a;
+    a++;
+    printf("%d\n", a);
+    printf("%d\n", a++);
+    printf("%d\n", ++a);
+    printf("%d\n", a);
+    --a;
+    a--;
+    printf("%d\n", a--);
+    printf("%d\n", --a);
+    printf("%d\n", a);
+}
+EOF
+
+# comma operator
+cat <<'EOF' > expected
+0 0
+1 1
+2 2
+3 3
+4 4
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+int main() {
+    int i = 1000;
+    int j = 1000;
+    for (i = 0, j = 0; i < 5; i++, j++) {
+        printf("%d %d\n", i, j);
+    }
+}
+EOF
+
+cat <<'EOF' > expected
+1 2 3 4
+0 0 5
+EOF
+
+test_diff <<'EOF'
+int printf();
+int x, y, z = 5;
+int main() {
+    int a, b;
+    a = 1, b = 2;
+    int c = 3, d = 4;
+    printf("%d %d %d %d\n", a, b, c, d);
+    printf("%d %d %d\n", x, y, z);
+}
+EOF
+
+# cast expressions
 cat <<'EOF' > expected
 65
 65
diff --git a/tests/function_macros.sh b/tests/function_macros.sh
deleted file mode 100644
index 1108650..0000000
--- a/tests/function_macros.sh
+++ /dev/null
@@ -1,110 +0,0 @@
-cat <<'EOF' > expected
-42
-246
-221
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-#define A(x) x
-#define B(x) x+x
-#define C(x, y) x*y
-
-int main() {
-    printf("%d\n", A(42));
-    printf("%d\n", B
-    (123));
-    printf("%d\n", C (13, 17));
-}
-EOF
-
-cat <<'EOF' > expected
-123
-EOF
-test_diff <<'EOF'
-#define A(x) x
-
-int printf();
-
-int main() {
-    printf("%d\n", A ( 123 ));
-}
-EOF
-
-cat <<'EOF' > expected
-main.c:4: expected ')', but got '<new-line>'
-EOF
-test_compile_error <<'EOF'
-#define A(x) x
-
-int main() {
-#if A (
-       123) < A(345)
-    printf("1\n");
-#endif
-}
-EOF
-
-cat <<'EOF' > expected
-42
-100 200
-300
-0
-1 2 3
-15
-42
-123
-879
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-#define ADD(a, b) ((a) + (b))
-#define PRINT_TWO(x, y) printf("%d %d\n", x, y)
-#define MAX(a, b) ((a) > (b) ? (a) : (b))
-#define NESTED(x) (x)
-#define CONCAT3(a, b, c) a ## b ## c
-
-int main() {
-    printf("%d\n", ADD(40, 2));
-    PRINT_TWO(100, 200);
-    printf("%d\n", MAX(100 + 200, 250));
-    printf("%d\n");
-    NESTED((printf("1 "), printf("2 "), printf("3\n"), 0));
-
-    int x = 5, y = 10;
-    printf("%d\n", ADD(x + 2, y - 2));
-    printf("%d\n", ADD(MAX(10, 20), MAX(15 + 5, 22)));
-    printf("%d\n", ADD(  100  ,  23  ));
-    printf("%d\n", ADD(NESTED((100 + 200)), MAX((123 + 456), (111 + 222))));
-}
-EOF
-
-cat <<'EOF' > expected
-int printf ( const char *, ...);
-
-int main () {
- int foo = 42;
- printf ( %d\n, foo);
-
- int a = 123;
- printf ( %d\n, a);
-}
-EOF
-test_cpp <<'EOF'
-int printf(const char*, ...);
-
-int main() {
-#define foo foo
-    int foo = 42;
-    printf("%d\n", foo);
-
-#define a b
-#define b c
-#define c a
-    int a = 123;
-    printf("%d\n", a);
-}
-EOF
diff --git a/tests/function_pointers.sh b/tests/function_pointers.sh
deleted file mode 100644
index cddc623..0000000
--- a/tests/function_pointers.sh
+++ /dev/null
@@ -1,24 +0,0 @@
-cat <<'EOF' > expected
-a
-h
-g
-EOF
-
-test_diff <<'EOF'
-int* f1(int a);
-int (*f2)(int a);
-
-extern int atexit (void (*) (void));
-extern int atexit (void (*fn) (void));
-
-int printf(const char*, ...);
-
-void g() { printf("g\n"); }
-void h() { printf("h\n"); }
-
-int main() {
-    atexit(g);
-    atexit(h);
-    printf("a\n");
-}
-EOF
diff --git a/tests/function_basics.c b/tests/functions.c
index 83fb66e..e9e622e 100644
--- a/tests/function_basics.c
+++ b/tests/functions.c
@@ -96,7 +96,17 @@ int f9(int select, int a, int b, int c, int d, S e, int f, int g) {
     }
 }
 
+// recursive functions
+int fib(int n) {
+    if (n <= 1) {
+        return 1;
+    } else {
+        return fib(n - 1) + fib(n - 2);
+    }
+}
+
 int main() {
+    // function basics
     ASSERT_EQ(66, foo());
     ASSERT_EQ(10, 10 * f(1, 2, 3, 4, 5, 6));
     ASSERT_EQ(20, 10 * f2(1, 2, 3, 4, 5, 6));
@@ -126,4 +136,7 @@ int main() {
     ASSERT_EQ(6, f9(5, 1, 2, 3, 4, s, 7, 8));
     ASSERT_EQ(7, f9(6, 1, 2, 3, 4, s, 7, 8));
     ASSERT_EQ(8, f9(7, 1, 2, 3, 4, s, 7, 8));
+
+    // recursive functions
+    ASSERT_EQ(89, fib(10));
 }
diff --git a/tests/functions.sh b/tests/functions.sh
new file mode 100644
index 0000000..ddae9b2
--- /dev/null
+++ b/tests/functions.sh
@@ -0,0 +1,148 @@
+# function pointers
+cat <<'EOF' > expected
+a
+h
+g
+EOF
+
+test_diff <<'EOF'
+int* f1(int a);
+int (*f2)(int a);
+
+extern int atexit (void (*) (void));
+extern int atexit (void (*fn) (void));
+
+int printf(const char*, ...);
+
+void g() { printf("g\n"); }
+void h() { printf("h\n"); }
+
+int main() {
+    atexit(g);
+    atexit(h);
+    printf("a\n");
+}
+EOF
+
+# void functions
+cat <<'EOF' > expected
+123
+EOF
+test_diff <<'EOF'
+int printf();
+
+void foo_bar(int hoge_piyo) {
+    printf("%d\n", hoge_piyo);
+}
+
+int main() {
+    foo_bar(123);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+EOF
+test_diff <<'EOF'
+struct S {
+    int a;
+};
+
+struct S* f();
+
+struct S* g() {}
+
+int main() {
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+hi
+EOF
+test_diff <<'EOF'
+int printf();
+
+void f() {
+    printf("hi\n");
+    return;
+}
+
+int main() {
+    f();
+    return 0;
+}
+EOF
+
+# variadic functions
+cat <<'EOF' > expected
+123
+456 789
+EOF
+
+test_diff <<'EOF'
+#include <stdarg.h>
+
+int fprintf();
+
+struct FILE;
+typedef struct FILE FILE;
+
+extern FILE* stdout;
+
+int vfprintf(FILE*, const char*, va_list);
+
+void fatal_error(const char* msg, ...) {
+    va_list args;
+    va_start(args, msg);
+    vfprintf(stdout, msg, args);
+    va_end(args);
+    fprintf(stdout, "\n");
+}
+
+int main() {
+    fatal_error("%d", 123);
+    fatal_error("%d %d", 456, 789);
+    return 0;
+}
+EOF
+
+test_exit_code 0 <<'EOF'
+#include <stdarg.h>
+#include <helpers.h>
+
+int sum(int n, ...) {
+    va_list args;
+    va_start(args, n);
+    int s = 0;
+    for (int i = 0; i < n; ++i) {
+        s += va_arg(args, int);
+    }
+    va_end(args);
+    return s;
+}
+
+int main() {
+    ASSERT_EQ(400, sum(5, 100, 90, 80, 70, 60));
+}
+EOF
+
+# implicit return
+# C99: 5.1.2.2.3
+test_exit_code 0 <<'EOF'
+int main() {
+}
+EOF
+
+test_exit_code 0 <<'EOF'
+int main() {
+    1 + 2 + 3;
+}
+EOF
+
+test_exit_code 0 <<'EOF'
+int main() {
+    if (1);
+    else return 1;
+}
+EOF
diff --git a/tests/global_variables.c b/tests/global_variables.c
deleted file mode 100644
index 20e0a64..0000000
--- a/tests/global_variables.c
+++ /dev/null
@@ -1,36 +0,0 @@
-#include <helpers.h>
-
-int printf(const char*, ...);
-int strcmp(const char*, const char*);
-
-int a;
-int* b = &a;
-int c[10];
-int* d = c;
-int e, *f = e, g[10], *h = g;
-
-char i = 42;
-short j = 123;
-int k = 999;
-
-char l[6] = "hello";
-
-int main() {
-    *b = 123;
-    ASSERT_EQ(123, a);
-
-    d[2] = 42;
-    ASSERT_EQ(42, c[2]);
-
-    *f = 456;
-    ASSERT_EQ(456, e);
-
-    h[5] = 789;
-    ASSERT_EQ(789, g[5]);
-
-    ASSERT_EQ(42, i);
-    ASSERT_EQ(123, j);
-    ASSERT_EQ(999, k);
-
-    ASSERT_EQ(0, strcmp("hello", l));
-}
diff --git a/tests/goto.sh b/tests/goto.sh
index 1e28a51..4d00031 100644
--- a/tests/goto.sh
+++ b/tests/goto.sh
@@ -1,4 +1,4 @@
-touch expected
+> expected
 test_diff <<'EOF'
 int main() {
     goto end;
diff --git a/tests/identifiers.sh b/tests/identifiers.sh
deleted file mode 100644
index ae00bd3..0000000
--- a/tests/identifiers.sh
+++ /dev/null
@@ -1,15 +0,0 @@
-cat <<'EOF' > expected
-42,123
-EOF
-test_diff <<'EOF'
-int printf();
-
-int main() {
-    int _a = 42;
-    int _b = 123;
-
-    printf("%d,%d\n", _a, _b);
-
-    return 0;
-}
-EOF
diff --git a/tests/implicit_return.sh b/tests/implicit_return.sh
deleted file mode 100644
index 20a8bed..0000000
--- a/tests/implicit_return.sh
+++ /dev/null
@@ -1,18 +0,0 @@
-# C99: 5.1.2.2.3
-test_exit_code 0 <<'EOF'
-int main() {
-}
-EOF
-
-test_exit_code 0 <<'EOF'
-int main() {
-    1 + 2 + 3;
-}
-EOF
-
-test_exit_code 0 <<'EOF'
-int main() {
-    if (1);
-    else return 1;
-}
-EOF
diff --git a/tests/include.sh b/tests/include.sh
new file mode 100644
index 0000000..33cabb4
--- /dev/null
+++ b/tests/include.sh
@@ -0,0 +1,189 @@
+cat <<'EOF' > header.h
+int add(int a, int b) {
+    return a + b;
+}
+
+int printf(const char*, ...);
+EOF
+
+cat <<'EOF' > expected
+8
+EOF
+test_diff <<'EOF'
+#include "header.h"
+
+int main() {
+    printf("%d\n", add(5, 3));
+    return 0;
+}
+EOF
+
+mkdir -p foo
+cat <<'EOF' > bar.h
+#include "baz.h"
+EOF
+cat <<'EOF' > baz.h
+#define A 123
+EOF
+cat <<'EOF' > foo/bar.h
+#include "baz.h"
+EOF
+cat <<'EOF' > foo/baz.h
+#define A 456
+EOF
+
+cat <<'EOF' > expected
+123
+456
+EOF
+test_diff <<'EOF'
+int printf(const char*, ...);
+
+int main() {
+#include "bar.h"
+    printf("%d\n", A);
+
+#undef A
+
+#include "foo/bar.h"
+    printf("%d\n", A);
+}
+EOF
+
+cat <<'EOF' > expected
+12
+EOF
+
+cat <<'EOF' > math.h
+int multiply(int a, int b) {
+    return a * b;
+}
+EOF
+
+cat <<'EOF' > calc.h
+#include "math.h"
+
+int calculate(int x) {
+    return multiply(x, 2);
+}
+
+int printf(const char*, ...);
+EOF
+
+test_diff <<'EOF'
+#include "calc.h"
+
+int main() {
+    printf("%d\n", calculate(6));
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+42
+EOF
+
+cat <<'EOF' > header.h
+#define A 42
+EOF
+
+test_diff <<'EOF'
+#include "header.h"
+
+int printf();
+
+int main() {
+    printf("%d\n", A);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+42
+EOF
+
+cat <<'EOF' > header.h
+#ifndef HEADER_H
+#define HEADER_H
+
+int f() { return 42; }
+
+#endif
+EOF
+
+test_diff <<'EOF'
+#include "header.h"
+#include "header.h"
+#include "header.h"
+
+int printf();
+
+int main() {
+    printf("%d\n", HEADER_H HEADER_H HEADER_H f() HEADER_H HEADER_H HEADER_H);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+main.c:1: cannot open include file: "nonexistent.h"
+EOF
+
+test_compile_error <<'EOF'
+#include "nonexistent.h"
+
+int main() {
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+include depth limit exceeded
+EOF
+
+# Create circular include files
+cat <<'EOF' > a.h
+#include "b.h"
+int a() { return 1; }
+EOF
+
+cat <<'EOF' > b.h
+#include "a.h"
+int b() { return 2; }
+EOF
+
+test_compile_error <<'EOF'
+#include "a.h"
+
+int main() {
+    a() + b();
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+main.c:1: cannot open include file: "hoge.h"
+EOF
+
+test_compile_error <<'EOF'
+#include "hoge.h"
+EOF
+
+cat <<'EOF' > expected
+main.c:1: cannot resolve include file name: <hoge.h>
+EOF
+
+test_compile_error <<'EOF'
+#include <hoge.h>
+EOF
+
+cat <<'EOF' > expected
+42
+EOF
+
+test_exit_code 0 <<'EOF'
+#ifdef FOO
+#include FOO
+#endif
+
+int main() { 1 < 2; }
+EOF
diff --git a/tests/include_errors.sh b/tests/include_errors.sh
deleted file mode 100644
index e0f856e..0000000
--- a/tests/include_errors.sh
+++ /dev/null
@@ -1,63 +0,0 @@
-cat <<'EOF' > expected
-main.c:1: cannot open include file: "nonexistent.h"
-EOF
-
-test_compile_error <<'EOF'
-#include "nonexistent.h"
-
-int main() {
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-include depth limit exceeded
-EOF
-
-# Create circular include files
-cat <<'EOF' > a.h
-#include "b.h"
-int a() { return 1; }
-EOF
-
-cat <<'EOF' > b.h
-#include "a.h"
-int b() { return 2; }
-EOF
-
-test_compile_error <<'EOF'
-#include "a.h"
-
-int main() {
-    a() + b();
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-main.c:1: cannot open include file: "hoge.h"
-EOF
-
-test_compile_error <<'EOF'
-#include "hoge.h"
-EOF
-
-cat <<'EOF' > expected
-main.c:1: cannot resolve include file name: <hoge.h>
-EOF
-
-test_compile_error <<'EOF'
-#include <hoge.h>
-EOF
-
-cat <<'EOF' > expected
-42
-EOF
-
-test_exit_code 0 <<'EOF'
-#ifdef FOO
-#include FOO
-#endif
-
-int main() { 1 < 2; }
-EOF
diff --git a/tests/include_guards.sh b/tests/include_guards.sh
deleted file mode 100644
index f8f0462..0000000
--- a/tests/include_guards.sh
+++ /dev/null
@@ -1,25 +0,0 @@
-cat <<'EOF' > expected
-42
-EOF
-
-cat <<'EOF' > header.h
-#ifndef HEADER_H
-#define HEADER_H
-
-int f() { return 42; }
-
-#endif
-EOF
-
-test_diff <<'EOF'
-#include "header.h"
-#include "header.h"
-#include "header.h"
-
-int printf();
-
-int main() {
-    printf("%d\n", HEADER_H HEADER_H HEADER_H f() HEADER_H HEADER_H HEADER_H);
-    return 0;
-}
-EOF
diff --git a/tests/include_local.sh b/tests/include_local.sh
deleted file mode 100644
index 05c42b7..0000000
--- a/tests/include_local.sh
+++ /dev/null
@@ -1,99 +0,0 @@
-cat <<'EOF' > header.h
-int add(int a, int b) {
-    return a + b;
-}
-
-int printf(const char*, ...);
-EOF
-
-cat <<'EOF' > expected
-8
-EOF
-test_diff <<'EOF'
-#include "header.h"
-
-int main() {
-    printf("%d\n", add(5, 3));
-    return 0;
-}
-EOF
-
-mkdir -p foo
-cat <<'EOF' > bar.h
-#include "baz.h"
-EOF
-cat <<'EOF' > baz.h
-#define A 123
-EOF
-cat <<'EOF' > foo/bar.h
-#include "baz.h"
-EOF
-cat <<'EOF' > foo/baz.h
-#define A 456
-EOF
-
-cat <<'EOF' > expected
-123
-456
-EOF
-test_diff <<'EOF'
-int printf(const char*, ...);
-
-int main() {
-#include "bar.h"
-    printf("%d\n", A);
-
-#undef A
-
-#include "foo/bar.h"
-    printf("%d\n", A);
-}
-EOF
-
-cat <<'EOF' > expected
-12
-EOF
-
-cat <<'EOF' > math.h
-int multiply(int a, int b) {
-    return a * b;
-}
-EOF
-
-cat <<'EOF' > calc.h
-#include "math.h"
-
-int calculate(int x) {
-    return multiply(x, 2);
-}
-
-int printf(const char*, ...);
-EOF
-
-test_diff <<'EOF'
-#include "calc.h"
-
-int main() {
-    printf("%d\n", calculate(6));
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-42
-EOF
-
-cat <<'EOF' > header.h
-#define A 42
-EOF
-
-test_diff <<'EOF'
-#include "header.h"
-
-int printf();
-
-int main() {
-    printf("%d\n", A);
-    return 0;
-}
-EOF
diff --git a/tests/increment_operators.sh b/tests/increment_operators.sh
deleted file mode 100644
index e7fb221..0000000
--- a/tests/increment_operators.sh
+++ /dev/null
@@ -1,28 +0,0 @@
-cat <<'EOF' > expected
-44
-44
-46
-46
-44
-42
-42
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-int main() {
-    int a = 42;
-    ++a;
-    a++;
-    printf("%d\n", a);
-    printf("%d\n", a++);
-    printf("%d\n", ++a);
-    printf("%d\n", a);
-    --a;
-    a--;
-    printf("%d\n", a--);
-    printf("%d\n", --a);
-    printf("%d\n", a);
-}
-EOF
diff --git a/tests/keywords.sh b/tests/keywords.sh
deleted file mode 100644
index 0bdb6f7..0000000
--- a/tests/keywords.sh
+++ /dev/null
@@ -1,14 +0,0 @@
-cat <<'EOF' > expected
-
-
-int printf ();
-int main () {}
-EOF
-
-test_cpp <<'EOF'
-// A keyword is treated as a normal identifier in preprocessing phase.
-#define auto int
-
-auto printf();
-auto main() {}
-EOF
diff --git a/tests/char_literals.c b/tests/literals.c
index cc592ff..7b84ea1 100644
--- a/tests/char_literals.c
+++ b/tests/literals.c
@@ -1,6 +1,13 @@
 #include <helpers.h>
 
 int main() {
+    // number literals
+    ASSERT_EQ(0, 0);
+    ASSERT_EQ(291, 0x123);
+    ASSERT_EQ(3405691582, 0xcafebabe);
+    ASSERT_EQ(436, 0664);
+
+    // char literals
     ASSERT_EQ(97, 'a');
     ASSERT_EQ(48, '0');
     ASSERT_EQ(92, '\\');
@@ -22,4 +29,12 @@ int main() {
     ASSERT_EQ(0, '\0');
 
     ASSERT_EQ(27, '\e');
+
+    // bool type
+    bool b1 = true, b0 = false;
+    ASSERT_EQ(1, b1);
+    ASSERT_EQ(0, b0);
+    ASSERT_EQ(1, sizeof(b1));
+    ASSERT_EQ(1, sizeof(b0));
+    ASSERT_EQ(1, sizeof(bool));
 }
diff --git a/tests/local_variables.c b/tests/local_variables.c
deleted file mode 100644
index ac63f04..0000000
--- a/tests/local_variables.c
+++ /dev/null
@@ -1,38 +0,0 @@
-#include <helpers.h>
-
-int main() {
-    int foo;
-    foo = 42;
-    ASSERT_EQ(42, foo);
-
-    int bar;
-    bar = 28;
-    ASSERT_EQ(70, foo + bar);
-
-    int a1;
-    int a2;
-    int a3;
-    int a4;
-    int a5;
-    int a6;
-    int a7;
-    int a8;
-    int a9;
-
-    a1 = 1;
-    a2 = 2;
-    a3 = 3;
-    a4 = 4;
-    a5 = 5;
-    a6 = 6;
-    a7 = 7;
-    a8 = 8;
-    a9 = 9;
-
-    ASSERT_EQ(45, a1 + a2 + a3 + a4 + a5 + a6 + a7 + a8 + a9 + 0);
-
-    int d = 2, e = d, f = d + e;
-    ASSERT_EQ(2, d);
-    ASSERT_EQ(2, e);
-    ASSERT_EQ(4, f);
-}
diff --git a/tests/logical_operators.sh b/tests/logical_operators.sh
deleted file mode 100644
index b4332e5..0000000
--- a/tests/logical_operators.sh
+++ /dev/null
@@ -1,67 +0,0 @@
-cat <<'EOF' > expected
-foo
-EOF
-test_diff <<'EOF'
-int printf();
-
-int foo() {
-    printf("foo\n");
-    return 0;
-}
-
-int bar() {
-    printf("bar\n");
-    return 1;
-}
-
-int main() {
-    if (foo() && bar()) {
-        printf("baz\n");
-    }
-
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-foo
-bar
-baz
-EOF
-test_diff <<'EOF'
-int printf();
-
-int foo() {
-    printf("foo\n");
-    return 0;
-}
-
-int bar() {
-    printf("bar\n");
-    return 1;
-}
-
-int main() {
-    if (foo() || bar()) {
-        printf("baz\n");
-    }
-
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-0
-1
-0
-EOF
-test_diff <<'EOF'
-int printf();
-
-int main() {
-    printf("%d\n", !1);
-    printf("%d\n", !0);
-    printf("%d\n", !23);
-    return 0;
-}
-EOF
diff --git a/tests/macro_operators.sh b/tests/macro_operators.sh
deleted file mode 100644
index 2954d53..0000000
--- a/tests/macro_operators.sh
+++ /dev/null
@@ -1,134 +0,0 @@
-cat <<'EOF' > expected
-int printf ();
-
-
-int foobar = 100;
-int prefix_test = 200;
-int test_suffix = 300;
-
-int var_1 = 10;
-int var_2 = 20;
-
-int var_A = 30;
-
-int number_12 = 12;
-
-int bazqux = 42;
-
-int main () {
- printf ( foobar=%d\n, foobar);
- printf ( prefix_test=%d\n, prefix_test);
- printf ( test_suffix=%d\n, test_suffix);
- printf ( var_1=%d\n, var_1);
- printf ( var_2=%d\n, var_2);
- printf ( var_A=%d\n, var_A);
- printf ( number_12=%d\n, number_12);
- return 0;
-}
-EOF
-
-test_cpp <<'EOF'
-int printf();
-
-#define CONCAT(a, b) a##b
-#define PREFIX(name) prefix_##name
-#define SUFFIX(name) name##_suffix
-
-int CONCAT(foo, bar) = 100;
-int PREFIX(test) = 200;
-int SUFFIX(test) = 300;
-
-#define MAKE_VAR(n) var_##n
-int MAKE_VAR(1) = 10;
-int MAKE_VAR(2) = 20;
-
-#define A 0
-int MAKE_VAR(A) = 30;
-
-#define NUMBER(x, y) number_##x##y
-int NUMBER(1, 2) = 12;
-
-#define CONCAT2(a, b) a ## b
-int CONCAT2(baz, qux) = 42;
-
-int main() {
-    printf("foobar=%d\n", foobar);
-    printf("prefix_test=%d\n", prefix_test);
-    printf("test_suffix=%d\n", test_suffix);
-    printf("var_1=%d\n", var_1);
-    printf("var_2=%d\n", var_2);
-    printf("var_A=%d\n", var_A);
-    printf("number_12=%d\n", number_12);
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-int printf ( const char *, ...);
-
-
-int H ( int n) { return n; }
-
-int main () {
- printf ( %d\n, H ( 123));
-}
-EOF
-
-test_cpp <<'EOF'
-int printf(const char*, ...);
-
-#define F(x) CHECK(G(x))
-#define G(x) CHECK(H(x))
-#define CHECK(x) x
-
-int H(int n) { return n; }
-
-int main() {
-    printf("%d\n", F(123));
-}
-EOF
-
-test_exit_code 0 <<'EOF'
-#include <helpers.h>
-
-int strcmp(const char*, const char*);
-
-#define FOO 42
-
-#define TO_STRING(x) TO_STRING_HELPER(x)
-#define TO_STRING_HELPER(x) #x
-#define BAR TO_STRING(FOO)
-
-#define TO_STRING2(x) #x
-#define BAZ TO_STRING2(FOO)
-
-int main() {
-    ASSERT_EQ(0, strcmp("42", BAR));
-    ASSERT_EQ(0, strcmp("FOO", BAZ));
-}
-EOF
-
-test_exit_code 0 <<'EOF'
-#include <helpers.h>
-
-#define CONCAT3(x, y, z) x##y##z
-#define FOO CONCAT3(, 2, 3)
-#define BAR CONCAT3(1, , 3)
-#define BAZ CONCAT3(1, 2, )
-
-int main() {
-    ASSERT_EQ(23, FOO);
-    ASSERT_EQ(13, BAR);
-    ASSERT_EQ(12, BAZ);
-}
-EOF
-
-cat <<'EOF' > expected
-foo
-EOF
-
-test_cpp <<'EOF'
-#define CONCAT(x, y) x ## y
-#define CONCAT2(name, r) CONCAT(name, r)
-CONCAT2(foo,)
-EOF
diff --git a/tests/macros.sh b/tests/macros.sh
new file mode 100644
index 0000000..69baae5
--- /dev/null
+++ b/tests/macros.sh
@@ -0,0 +1,426 @@
+cat <<'EOF' > expected
+EOF
+test_diff <<'EOF'
+#define A 1
+int main() {
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+1,2,3
+EOF
+test_diff <<'EOF'
+int printf();
+
+#define A 1
+#define B 2
+#define C 3
+
+int main() {
+    printf("%d,%d,%d\n", A, B, C);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+0,0,0,0
+EOF
+test_diff <<'EOF'
+int printf();
+
+#define NULL 0
+#define TK_EOF        0
+#define TY_UNKNOWN 0
+#define AST_UNKNOWN       0
+
+int main() {
+    printf("%d,%d,%d,%d\n", NULL, TK_EOF, TY_UNKNOWN, AST_UNKNOWN);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+42,123
+EOF
+test_diff <<'EOF'
+int printf();
+
+#define A foo_a
+#define B foo_b
+
+int main() {
+    int foo_a = 42;
+    int foo_b = 123;
+
+    printf("%d,%d\n", A, B);
+
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+123
+EOF
+
+test_diff <<'EOF'
+#define foo() 123
+
+int printf();
+
+int main() {
+    printf("%d\n", foo());
+}
+EOF
+
+cat <<'EOF' > expected
+579
+975
+EOF
+
+test_diff <<'EOF'
+#define foo 123 + 456
+#define bar() 321 + 654
+
+int printf();
+
+int main() {
+    printf("%d\n", foo);
+    printf("%d\n", bar());
+}
+EOF
+
+cat <<'EOF' > expected
+42
+246
+221
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+#define A(x) x
+#define B(x) x+x
+#define C(x, y) x*y
+
+int main() {
+    printf("%d\n", A(42));
+    printf("%d\n", B
+    (123));
+    printf("%d\n", C (13, 17));
+}
+EOF
+
+cat <<'EOF' > expected
+123
+EOF
+test_diff <<'EOF'
+#define A(x) x
+
+int printf();
+
+int main() {
+    printf("%d\n", A ( 123 ));
+}
+EOF
+
+cat <<'EOF' > expected
+main.c:4: expected ')', but got '<new-line>'
+EOF
+test_compile_error <<'EOF'
+#define A(x) x
+
+int main() {
+#if A (
+       123) < A(345)
+    printf("1\n");
+#endif
+}
+EOF
+
+cat <<'EOF' > expected
+42
+100 200
+300
+0
+1 2 3
+15
+42
+123
+879
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+#define ADD(a, b) ((a) + (b))
+#define PRINT_TWO(x, y) printf("%d %d\n", x, y)
+#define MAX(a, b) ((a) > (b) ? (a) : (b))
+#define NESTED(x) (x)
+#define CONCAT3(a, b, c) a ## b ## c
+
+int main() {
+    printf("%d\n", ADD(40, 2));
+    PRINT_TWO(100, 200);
+    printf("%d\n", MAX(100 + 200, 250));
+    printf("%d\n");
+    NESTED((printf("1 "), printf("2 "), printf("3\n"), 0));
+
+    int x = 5, y = 10;
+    printf("%d\n", ADD(x + 2, y - 2));
+    printf("%d\n", ADD(MAX(10, 20), MAX(15 + 5, 22)));
+    printf("%d\n", ADD(  100  ,  23  ));
+    printf("%d\n", ADD(NESTED((100 + 200)), MAX((123 + 456), (111 + 222))));
+}
+EOF
+
+cat <<'EOF' > expected
+int printf ( const char *, ...);
+
+int main () {
+ int foo = 42;
+ printf ( %d\n, foo);
+
+ int a = 123;
+ printf ( %d\n, a);
+}
+EOF
+test_cpp <<'EOF'
+int printf(const char*, ...);
+
+int main() {
+#define foo foo
+    int foo = 42;
+    printf("%d\n", foo);
+
+#define a b
+#define b c
+#define c a
+    int a = 123;
+    printf("%d\n", a);
+}
+EOF
+
+cat <<'EOF' > expected
+int printf ();
+
+
+int foobar = 100;
+int prefix_test = 200;
+int test_suffix = 300;
+
+int var_1 = 10;
+int var_2 = 20;
+
+int var_A = 30;
+
+int number_12 = 12;
+
+int bazqux = 42;
+
+int main () {
+ printf ( foobar=%d\n, foobar);
+ printf ( prefix_test=%d\n, prefix_test);
+ printf ( test_suffix=%d\n, test_suffix);
+ printf ( var_1=%d\n, var_1);
+ printf ( var_2=%d\n, var_2);
+ printf ( var_A=%d\n, var_A);
+ printf ( number_12=%d\n, number_12);
+ return 0;
+}
+EOF
+
+test_cpp <<'EOF'
+int printf();
+
+#define CONCAT(a, b) a##b
+#define PREFIX(name) prefix_##name
+#define SUFFIX(name) name##_suffix
+
+int CONCAT(foo, bar) = 100;
+int PREFIX(test) = 200;
+int SUFFIX(test) = 300;
+
+#define MAKE_VAR(n) var_##n
+int MAKE_VAR(1) = 10;
+int MAKE_VAR(2) = 20;
+
+#define A 0
+int MAKE_VAR(A) = 30;
+
+#define NUMBER(x, y) number_##x##y
+int NUMBER(1, 2) = 12;
+
+#define CONCAT2(a, b) a ## b
+int CONCAT2(baz, qux) = 42;
+
+int main() {
+    printf("foobar=%d\n", foobar);
+    printf("prefix_test=%d\n", prefix_test);
+    printf("test_suffix=%d\n", test_suffix);
+    printf("var_1=%d\n", var_1);
+    printf("var_2=%d\n", var_2);
+    printf("var_A=%d\n", var_A);
+    printf("number_12=%d\n", number_12);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+int printf ( const char *, ...);
+
+
+int H ( int n) { return n; }
+
+int main () {
+ printf ( %d\n, H ( 123));
+}
+EOF
+
+test_cpp <<'EOF'
+int printf(const char*, ...);
+
+#define F(x) CHECK(G(x))
+#define G(x) CHECK(H(x))
+#define CHECK(x) x
+
+int H(int n) { return n; }
+
+int main() {
+    printf("%d\n", F(123));
+}
+EOF
+
+test_exit_code 0 <<'EOF'
+#include <helpers.h>
+
+int strcmp(const char*, const char*);
+
+#define FOO 42
+
+#define TO_STRING(x) TO_STRING_HELPER(x)
+#define TO_STRING_HELPER(x) #x
+#define BAR TO_STRING(FOO)
+
+#define TO_STRING2(x) #x
+#define BAZ TO_STRING2(FOO)
+
+int main() {
+    ASSERT_EQ(0, strcmp("42", BAR));
+    ASSERT_EQ(0, strcmp("FOO", BAZ));
+}
+EOF
+
+test_exit_code 0 <<'EOF'
+#include <helpers.h>
+
+#define CONCAT3(x, y, z) x##y##z
+#define FOO CONCAT3(, 2, 3)
+#define BAR CONCAT3(1, , 3)
+#define BAZ CONCAT3(1, 2, )
+
+int main() {
+    ASSERT_EQ(23, FOO);
+    ASSERT_EQ(13, BAR);
+    ASSERT_EQ(12, BAZ);
+}
+EOF
+
+cat <<'EOF' > expected
+foo
+EOF
+
+test_cpp <<'EOF'
+#define CONCAT(x, y) x ## y
+#define CONCAT2(name, r) CONCAT(name, r)
+CONCAT2(foo,)
+EOF
+
+cat <<'EOF' > expected
+1
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+int main() {
+    printf("%d\n", __ducc__);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+main.c
+main.c
+main.c
+EOF
+
+cat <<'EOF' > header.h
+#define A __FILE__
+EOF
+
+test_diff <<'EOF'
+#define B __FILE__
+#include "header.h"
+int printf();
+int main() {
+    printf("%s\n", __FILE__);
+    printf("%s\n", B);
+    printf("%s\n", A);
+}
+EOF
+
+cat <<'EOF' > expected
+5
+6 6
+7 7
+EOF
+
+cat <<'EOF' > header.h
+#define A __LINE__
+EOF
+
+test_diff <<'EOF'
+#define B __LINE__
+#include "header.h"
+int printf();
+int main() {
+    printf("%d\n", __LINE__);
+    printf("%d %d\n", B, B);
+    printf("%d %d\n", A, A);
+}
+EOF
+
+cat <<'EOF' > expected
+int printf ();
+
+int main () {
+
+ printf ( A is defined\n);
+
+
+ printf ( A is undefined\n);
+}
+EOF
+
+test_cpp <<'EOF'
+int printf();
+
+int main() {
+#define A 1
+
+#ifdef A
+    printf("A is defined\n");
+#else
+    printf("A is undefined\n");
+#endif
+
+#undef A
+
+#ifdef A
+    printf("A is defined\n");
+#else
+    printf("A is undefined\n");
+#endif
+}
+EOF
diff --git a/tests/number_literals.c b/tests/number_literals.c
deleted file mode 100644
index c28e4e3..0000000
--- a/tests/number_literals.c
+++ /dev/null
@@ -1,8 +0,0 @@
-#include <helpers.h>
-
-int main() {
-    ASSERT_EQ(0, 0);
-    ASSERT_EQ(291, 0x123);
-    ASSERT_EQ(3405691582, 0xcafebabe);
-    ASSERT_EQ(436, 0664);
-}
diff --git a/tests/operators.c b/tests/operators.c
new file mode 100644
index 0000000..9e9ba08
--- /dev/null
+++ b/tests/operators.c
@@ -0,0 +1,122 @@
+#include <helpers.h>
+
+int main() {
+    // arithmetic operators
+    ASSERT_EQ(42, 42);
+    ASSERT_EQ(21, 5 + 20 - 4);
+    ASSERT_EQ(26, 2 * 3 + 4 * 5);
+    ASSERT_EQ(197, (((3 + 5) / 2) + (5 * (9 - 6)) * (5 + 6 * 7)) % 256);
+    ASSERT_EQ(30, (-10 + 20 * -3) + 100);
+
+    // comparison operators
+    ASSERT_EQ(1, 0 == 0);
+    ASSERT_EQ(0, 123 != 123);
+    ASSERT_EQ(1, 123 != 456);
+    ASSERT_EQ(0, 123 == 124);
+    ASSERT_EQ(1, 123 < 567);
+    ASSERT_EQ(1, 123 <= 567);
+    ASSERT_EQ(1, 123 <= 123);
+    ASSERT_EQ(0, 123 < 123);
+
+    // bitwise operators
+    ASSERT_EQ(123, 0 | 123);
+    ASSERT_EQ(460, 12 | 456);
+
+    ASSERT_EQ(8, 1 << 3);
+    ASSERT_EQ(336, 21 << 4);
+    ASSERT_EQ(13, 111 >> 3);
+    ASSERT_EQ(0, 15 >> 14);
+
+    int a = 5;
+    int b = 3;
+    ASSERT_EQ(1, a & b);
+    ASSERT_EQ(7, a | b);
+    ASSERT_EQ(6, a ^ b);
+    ASSERT_EQ(4, 2 + 3 & 4);
+
+    int c = 1 + 2 & 3;
+    int d = 4 & 5 ^ 6;
+    int e = 1 ^ 2 | 3;
+    int f = 0 | 1 & 2;
+    ASSERT_EQ(3, c);
+    ASSERT_EQ(2, d);
+    ASSERT_EQ(3, e);
+    ASSERT_EQ(0, f);
+
+    ASSERT_EQ(-1, ~0);
+    ASSERT_EQ(-2, ~1);
+    ASSERT_EQ(-6, ~5);
+    ASSERT_EQ(0, ~(-1));
+    ASSERT_EQ(5, ~(-6));
+
+    int x = 10;
+    ASSERT_EQ(-11, ~x);
+    ASSERT_EQ(-1, ~(x & 0));
+    ASSERT_EQ(-16, ~(x | 5));
+
+    // assignment operators
+    int i = 0;
+    for (; i < 5; i += 1) {
+    }
+    ASSERT_EQ(5, i);
+
+    for (i = 5; i >= 0; i -= 1)
+        ;
+    ASSERT_EQ(-1, i);
+
+    x = 123;
+    x *= 456;
+    ASSERT_EQ(56088, x);
+
+    int y = 120;
+    y /= 5;
+    ASSERT_EQ(24, y);
+
+    int z = 17;
+    z %= 7;
+    ASSERT_EQ(3, z);
+
+    a = 0x05;
+    a |= 0x0A;
+    ASSERT_EQ(0x0F, a);
+
+    b = 0x0F;
+    b &= 0x0A;
+    ASSERT_EQ(0x0A, b);
+
+    c = 7;
+    c |= 8;
+    ASSERT_EQ(15, c);
+
+    d = 15;
+    d &= 6;
+    ASSERT_EQ(6, d);
+
+    e = 0x0F;
+    e ^= 0x05;
+    ASSERT_EQ(0x0A, e);
+
+    f = 3;
+    f <<= 2;
+    ASSERT_EQ(12, f);
+
+    int g = 16;
+    g >>= 2;
+    ASSERT_EQ(4, g);
+
+    int h = -16;
+    h >>= 2;
+    ASSERT_EQ(-4, h);
+
+    int j = 1;
+    j <<= 4;
+    ASSERT_EQ(16, j);
+
+    int k = 64;
+    k >>= 3;
+    ASSERT_EQ(8, k);
+
+    // ternary operator
+    ASSERT_EQ(2, 1 ? 2 : 3);
+    ASSERT_EQ(5, 0 ? 4 : 5);
+}
diff --git a/tests/pointer_basics.sh b/tests/pointer_basics.sh
deleted file mode 100644
index 6faa421..0000000
--- a/tests/pointer_basics.sh
+++ /dev/null
@@ -1,79 +0,0 @@
-cat <<'EOF' > expected
-EOF
-test_diff <<'EOF'
-int main() {
-    int a1;
-    int* a2;
-    char a3;
-    char* a4;
-    long a5;
-    long* a6;
-    void* a8;
-    int** a10;
-    char** a12;
-    long** a14;
-    void** a16;
-    int*** a18;
-    char*** a20;
-    long*** a22;
-    void*** a24;
-    int* const* const* a25;
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-42 42
-EOF
-test_diff <<'EOF'
-int printf();
-
-int main() {
-    int x;
-    int* y;
-    y = &x;
-    *y = 42;
-    printf("%d %d\n", x, *y);
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-3
-3
-3
-EOF
-test_diff <<'EOF'
-int printf();
-
-int main() {
-    char c;
-    int i;
-    long l;
-    c = 42;
-    i = 42*2;
-    l = 42*3;
-
-    char* cp1;
-    char* cp2;
-    int* ip1;
-    int* ip2;
-    long* lp1;
-    long* lp2;
-
-    cp1 = &c;
-    cp2 = &c + 3;
-
-    ip1 = &i;
-    ip2 = &i + 3;
-
-    lp1 = &l;
-    lp2 = &l + 3;
-
-    printf("%d\n", cp2 - cp1);
-    printf("%d\n", ip2 - ip1);
-    printf("%d\n", lp2 - lp1);
-
-    return 0;
-}
-EOF
diff --git a/tests/array_basics.sh b/tests/pointers.sh
index e50a3c0..bbd4ed4 100644
--- a/tests/array_basics.sh
+++ b/tests/pointers.sh
@@ -1,3 +1,85 @@
+# pointer basics
+cat <<'EOF' > expected
+EOF
+test_diff <<'EOF'
+int main() {
+    int a1;
+    int* a2;
+    char a3;
+    char* a4;
+    long a5;
+    long* a6;
+    void* a8;
+    int** a10;
+    char** a12;
+    long** a14;
+    void** a16;
+    int*** a18;
+    char*** a20;
+    long*** a22;
+    void*** a24;
+    int* const* const* a25;
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+42 42
+EOF
+test_diff <<'EOF'
+int printf();
+
+int main() {
+    int x;
+    int* y;
+    y = &x;
+    *y = 42;
+    printf("%d %d\n", x, *y);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+3
+3
+3
+EOF
+test_diff <<'EOF'
+int printf();
+
+int main() {
+    char c;
+    int i;
+    long l;
+    c = 42;
+    i = 42*2;
+    l = 42*3;
+
+    char* cp1;
+    char* cp2;
+    int* ip1;
+    int* ip2;
+    long* lp1;
+    long* lp2;
+
+    cp1 = &c;
+    cp2 = &c + 3;
+
+    ip1 = &i;
+    ip2 = &i + 3;
+
+    lp1 = &l;
+    lp2 = &l + 3;
+
+    printf("%d\n", cp2 - cp1);
+    printf("%d\n", ip2 - ip1);
+    printf("%d\n", lp2 - lp1);
+
+    return 0;
+}
+EOF
+
+# arrays
 cat <<'EOF' > expected
 42
 EOF
@@ -160,3 +242,76 @@ int main() {
     printf("%zu\n", sizeof(c));
 }
 EOF
+
+# string operations
+> expected
+test_diff <<'EOF'
+int main() {
+    "";
+    return 0;
+}
+EOF
+
+> expected
+test_diff <<'EOF'
+int main() {
+    "abc";
+    return 0;
+}
+EOF
+
+> expected
+test_diff <<'EOF'
+int main() {
+    "\"foo\"bar\\\n\"";
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+abc
+defghijkl
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+int main() {
+    printf("abc\n");
+    printf("def" "ghi"
+    "jkl\n");
+}
+EOF
+
+cat <<'EOF' > expected
+h
+l
+,
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+int main() {
+    char* h = " hello,world" + 1;
+    printf("%c\n", *h);
+    printf("%c\n", h[2]);
+    printf("%c\n", *(h + 5));
+}
+EOF
+
+cat <<'EOF' > expected
+105
+0
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+int main() {
+    char* s = "hi";
+    while (*s++) {
+        printf("%d\n", *s);
+    }
+}
+EOF
diff --git a/tests/predefined_macros.sh b/tests/predefined_macros.sh
deleted file mode 100644
index ada2fdd..0000000
--- a/tests/predefined_macros.sh
+++ /dev/null
@@ -1,54 +0,0 @@
-cat <<'EOF' > expected
-1
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-int main() {
-    printf("%d\n", __ducc__);
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-main.c
-main.c
-main.c
-EOF
-
-cat <<'EOF' > header.h
-#define A __FILE__
-EOF
-
-test_diff <<'EOF'
-#define B __FILE__
-#include "header.h"
-int printf();
-int main() {
-    printf("%s\n", __FILE__);
-    printf("%s\n", B);
-    printf("%s\n", A);
-}
-EOF
-
-cat <<'EOF' > expected
-5
-6 6
-7 7
-EOF
-
-cat <<'EOF' > header.h
-#define A __LINE__
-EOF
-
-test_diff <<'EOF'
-#define B __LINE__
-#include "header.h"
-int printf();
-int main() {
-    printf("%d\n", __LINE__);
-    printf("%d %d\n", B, B);
-    printf("%d %d\n", A, A);
-}
-EOF
diff --git a/tests/printf.sh b/tests/printf.sh
index 7c4454c..ec805dc 100644
--- a/tests/printf.sh
+++ b/tests/printf.sh
@@ -1,4 +1,4 @@
-touch expected
+> expected
 test_diff <<'EOF'
 int printf();
 
diff --git a/tests/recursive_functions.c b/tests/recursive_functions.c
deleted file mode 100644
index b81824a..0000000
--- a/tests/recursive_functions.c
+++ /dev/null
@@ -1,13 +0,0 @@
-#include <helpers.h>
-
-int fib(int n) {
-    if (n <= 1) {
-        return 1;
-    } else {
-        return fib(n - 1) + fib(n - 2);
-    }
-}
-
-int main() {
-    ASSERT_EQ(89, fib(10));
-}
diff --git a/tests/short_type.sh b/tests/short_type.sh
deleted file mode 100644
index b298a98..0000000
--- a/tests/short_type.sh
+++ /dev/null
@@ -1,16 +0,0 @@
-cat <<'EOF' > expected
-2 42
-8 123
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-int main() {
-    short a = 42;
-    printf("%zu %hd\n", sizeof(a), a);
-    short* b = &a;
-    *b = 123;
-    printf("%zu %hd\n", sizeof(b), *b);
-}
-EOF
diff --git a/tests/stdlib_declarations.sh b/tests/stdlib_declarations.sh
deleted file mode 100644
index efd6a30..0000000
--- a/tests/stdlib_declarations.sh
+++ /dev/null
@@ -1,21 +0,0 @@
-cat <<'EOF' > expected
-EOF
-test_diff <<'EOF'
-typedef long size_t;
-
-int atoi(const char*);
-void* calloc(size_t, size_t);
-void exit(int);
-int getchar(void);
-int isalnum(int);
-int isalpha(int);
-int isdigit(int);
-int isspace(int);
-void* memcpy(void*, void*, size_t);
-int printf(const char*, ...);
-int sprintf(char*, const char*, ...);
-int strcmp(const char*, const char*);
-char* strstr(const char*, const char*);
-
-int main() { return 0; }
-EOF
diff --git a/tests/string_operations.sh b/tests/string_operations.sh
deleted file mode 100644
index 2466145..0000000
--- a/tests/string_operations.sh
+++ /dev/null
@@ -1,71 +0,0 @@
-touch expected
-test_diff <<'EOF'
-int main() {
-    "";
-    return 0;
-}
-EOF
-
-touch expected
-test_diff <<'EOF'
-int main() {
-    "abc";
-    return 0;
-}
-EOF
-
-touch expected
-test_diff <<'EOF'
-int main() {
-    "\"foo\"bar\\\n\"";
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-abc
-defghijkl
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-int main() {
-    printf("abc\n");
-    printf("def" "ghi"
-    "jkl\n");
-}
-EOF
-
-cat <<'EOF' > expected
-h
-l
-,
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-int main() {
-    char* h = " hello,world" + 1;
-    printf("%c\n", *h);
-    printf("%c\n", h[2]);
-    printf("%c\n", *(h + 5));
-}
-EOF
-
-cat <<'EOF' > expected
-105
-0
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-int main() {
-    char* s = "hi";
-    while (*s++) {
-        printf("%d\n", *s);
-    }
-}
-EOF
diff --git a/tests/struct_arrays.sh b/tests/struct_arrays.sh
deleted file mode 100644
index 628c0d3..0000000
--- a/tests/struct_arrays.sh
+++ /dev/null
@@ -1,33 +0,0 @@
-cat <<'EOF' > expected
-20
-10
-20
-30
-40
-50
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-struct S {
-    int a[5];
-};
-
-int main() {
-    struct S x;
-    x.a[0] = 10;
-    x.a[1] = 20;
-    x.a[2] = 30;
-    x.a[3] = 40;
-    x.a[4] = 50;
-
-    printf("%zu\n", sizeof(struct S));
-
-    printf("%d\n", x.a[0]);
-    printf("%d\n", x.a[1]);
-    printf("%d\n", x.a[2]);
-    printf("%d\n", x.a[3]);
-    printf("%d\n", x.a[4]);
-}
-EOF
diff --git a/tests/struct_basics.sh b/tests/struct_basics.sh
deleted file mode 100644
index 13a50a5..0000000
--- a/tests/struct_basics.sh
+++ /dev/null
@@ -1,137 +0,0 @@
-cat <<'EOF' > expected
-EOF
-test_diff <<'EOF'
-struct Token {
-    int kind;
-    char* value;
-};
-
-struct Define {
-    char* from;
-    struct Token* to;
-};
-
-struct AstNode;
-
-struct Type {
-    int kind;
-    struct Type* to;
-    struct AstNode* members;
-};
-
-struct AstNode {
-    int kind;
-    struct AstNode* next;
-    struct AstNode* last;
-    char* name;
-    struct AstNode* func_params;
-    struct AstNode* func_body;
-    int int_value;
-    struct AstNode* expr1;
-    struct AstNode* expr2;
-    struct AstNode* expr3;
-    int op;
-    struct Type* ty;
-    int var_index;
-    struct AstNode* node1;
-    struct AstNode* node2;
-    char** str_literals;
-};
-
-struct LVar {
-    char* name;
-    struct Type* ty;
-};
-
-struct Func {
-    char* name;
-    struct Type* ty;
-};
-
-struct Parser {
-    struct Token* tokens;
-    int pos;
-    struct LVar* locals;
-    int n_locals;
-    struct Func* funcs;
-    int n_funcs;
-    char** str_literals;
-    int n_str_literals;
-};
-
-struct CodeGen {
-    int next_label;
-    int* loop_labels;
-};
-
-int main() {
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-42
-123
-EOF
-test_diff <<'EOF'
-struct S {
-    int a;
-    int b;
-};
-
-int printf();
-void* calloc();
-
-int main() {
-    struct S* sp;
-    sp = calloc(1, sizeof(struct S));
-    sp->a = 42;
-    printf("%d\n", sp->a);
-    (*sp).b = 123;
-    printf("%d\n", (*sp).b);
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-42
-EOF
-test_diff <<'EOF'
-void* calloc();
-int printf();
-
-struct T;
-
-struct S {
-    struct T* a;
-};
-
-struct T {
-    int b;
-};
-
-int main() {
-    struct S* s = calloc(1, sizeof(struct S));
-    s->a = calloc(1, sizeof(struct T));
-    s->a->b = 42;
-    printf("%d\n", s->a->b);
-    return 0;
-}
-EOF
-
-test_exit_code 0 <<'EOF'
-#include <helpers.h>
-
-struct S {
-    int a, b;
-};
-
-struct T {
-    short *a, b, c[12];
-};
-
-int main() {
-    ASSERT_EQ(8, sizeof(struct S));
-    ASSERT_EQ(40, sizeof(struct T));
-}
-EOF
diff --git a/tests/struct_initialization.sh b/tests/struct_initialization.sh
deleted file mode 100644
index f2c92cf..0000000
--- a/tests/struct_initialization.sh
+++ /dev/null
@@ -1,107 +0,0 @@
-cat <<'EOF' > expected
-0
-1
-EOF
-test_diff <<'EOF'
-int printf();
-void* calloc();
-
-struct S {
-    int a;
-    int b;
-};
-
-int main() {
-    struct S* s = calloc(1, sizeof(struct S));
-    s->b = 1;
-    printf("%ld\n", s->a);
-    printf("%ld\n", s->b);
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-123 456
-0 0
-123 456
-EOF
-
-test_diff <<'EOF'
-struct S {
-    int a;
-    int b;
-};
-typedef struct S S;
-
-void* calloc();
-int printf();
-
-int main() {
-    S* s1 = calloc(1, sizeof(S));
-    S* s2 = calloc(1, sizeof(S));
-    s1->a = 123;
-    s1->b = 456;
-    printf("%d %d\n", s1->a, s1->b);
-    printf("%d %d\n", s2->a, s2->b);
-    *s2 = *s1;
-    printf("%d %d\n", s2->a, s2->b);
-}
-EOF
-
-cat <<'EOF' > expected
-123 456
-0 0
-123 456
-EOF
-
-test_diff <<'EOF'
-struct S {
-    long a;
-    long b;
-};
-typedef struct S S;
-
-void* calloc();
-int printf();
-
-int main() {
-    S* s1 = calloc(1, sizeof(S));
-    S* s2 = calloc(1, sizeof(S));
-    s1->a = 123;
-    s1->b = 456;
-    printf("%d %d\n", s1->a, s1->b);
-    printf("%d %d\n", s2->a, s2->b);
-    *s2 = *s1;
-    printf("%d %d\n", s2->a, s2->b);
-}
-EOF
-
-cat <<'EOF' > expected
-123 456
-0 0
-123 456
-EOF
-
-test_diff <<'EOF'
-struct S {
-    long a;
-    long b;
-};
-typedef struct S S;
-
-void* calloc();
-int printf();
-
-int main() {
-    S s1;
-    S s2;
-    s1.a = 123;
-    s1.b = 456;
-    s2.a = 0;
-    s2.b = 0;
-    printf("%d %d\n", s1.a, s1.b);
-    printf("%d %d\n", s2.a, s2.b);
-    s2 = s1;
-    printf("%d %d\n", s2.a, s2.b);
-}
-EOF
diff --git a/tests/structs.sh b/tests/structs.sh
new file mode 100644
index 0000000..4c8ff6d
--- /dev/null
+++ b/tests/structs.sh
@@ -0,0 +1,364 @@
+cat <<'EOF' > expected
+EOF
+test_diff <<'EOF'
+struct Token {
+    int kind;
+    char* value;
+};
+
+struct Define {
+    char* from;
+    struct Token* to;
+};
+
+struct AstNode;
+
+struct Type {
+    int kind;
+    struct Type* to;
+    struct AstNode* members;
+};
+
+struct AstNode {
+    int kind;
+    struct AstNode* next;
+    struct AstNode* last;
+    char* name;
+    struct AstNode* func_params;
+    struct AstNode* func_body;
+    int int_value;
+    struct AstNode* expr1;
+    struct AstNode* expr2;
+    struct AstNode* expr3;
+    int op;
+    struct Type* ty;
+    int var_index;
+    struct AstNode* node1;
+    struct AstNode* node2;
+    char** str_literals;
+};
+
+struct LVar {
+    char* name;
+    struct Type* ty;
+};
+
+struct Func {
+    char* name;
+    struct Type* ty;
+};
+
+struct Parser {
+    struct Token* tokens;
+    int pos;
+    struct LVar* locals;
+    int n_locals;
+    struct Func* funcs;
+    int n_funcs;
+    char** str_literals;
+    int n_str_literals;
+};
+
+struct CodeGen {
+    int next_label;
+    int* loop_labels;
+};
+
+int main() {
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+42
+123
+EOF
+test_diff <<'EOF'
+struct S {
+    int a;
+    int b;
+};
+
+int printf();
+void* calloc();
+
+int main() {
+    struct S* sp;
+    sp = calloc(1, sizeof(struct S));
+    sp->a = 42;
+    printf("%d\n", sp->a);
+    (*sp).b = 123;
+    printf("%d\n", (*sp).b);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+42
+EOF
+test_diff <<'EOF'
+void* calloc();
+int printf();
+
+struct T;
+
+struct S {
+    struct T* a;
+};
+
+struct T {
+    int b;
+};
+
+int main() {
+    struct S* s = calloc(1, sizeof(struct S));
+    s->a = calloc(1, sizeof(struct T));
+    s->a->b = 42;
+    printf("%d\n", s->a->b);
+    return 0;
+}
+EOF
+
+test_exit_code 0 <<'EOF'
+#include <helpers.h>
+
+struct S {
+    int a, b;
+};
+
+struct T {
+    short *a, b, c[12];
+};
+
+int main() {
+    ASSERT_EQ(8, sizeof(struct S));
+    ASSERT_EQ(40, sizeof(struct T));
+}
+EOF
+
+cat <<'EOF' > expected
+20
+10
+20
+30
+40
+50
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+struct S {
+    int a[5];
+};
+
+int main() {
+    struct S x;
+    x.a[0] = 10;
+    x.a[1] = 20;
+    x.a[2] = 30;
+    x.a[3] = 40;
+    x.a[4] = 50;
+
+    printf("%zu\n", sizeof(struct S));
+
+    printf("%d\n", x.a[0]);
+    printf("%d\n", x.a[1]);
+    printf("%d\n", x.a[2]);
+    printf("%d\n", x.a[3]);
+    printf("%d\n", x.a[4]);
+}
+EOF
+
+cat <<'EOF' > expected
+0
+1
+EOF
+test_diff <<'EOF'
+int printf();
+void* calloc();
+
+struct S {
+    int a;
+    int b;
+};
+
+int main() {
+    struct S* s = calloc(1, sizeof(struct S));
+    s->b = 1;
+    printf("%ld\n", s->a);
+    printf("%ld\n", s->b);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+123 456
+0 0
+123 456
+EOF
+
+test_diff <<'EOF'
+struct S {
+    int a;
+    int b;
+};
+typedef struct S S;
+
+void* calloc();
+int printf();
+
+int main() {
+    S* s1 = calloc(1, sizeof(S));
+    S* s2 = calloc(1, sizeof(S));
+    s1->a = 123;
+    s1->b = 456;
+    printf("%d %d\n", s1->a, s1->b);
+    printf("%d %d\n", s2->a, s2->b);
+    *s2 = *s1;
+    printf("%d %d\n", s2->a, s2->b);
+}
+EOF
+
+cat <<'EOF' > expected
+123 456
+0 0
+123 456
+EOF
+
+test_diff <<'EOF'
+struct S {
+    long a;
+    long b;
+};
+typedef struct S S;
+
+void* calloc();
+int printf();
+
+int main() {
+    S* s1 = calloc(1, sizeof(S));
+    S* s2 = calloc(1, sizeof(S));
+    s1->a = 123;
+    s1->b = 456;
+    printf("%d %d\n", s1->a, s1->b);
+    printf("%d %d\n", s2->a, s2->b);
+    *s2 = *s1;
+    printf("%d %d\n", s2->a, s2->b);
+}
+EOF
+
+cat <<'EOF' > expected
+123 456
+0 0
+123 456
+EOF
+
+test_diff <<'EOF'
+struct S {
+    long a;
+    long b;
+};
+typedef struct S S;
+
+void* calloc();
+int printf();
+
+int main() {
+    S s1;
+    S s2;
+    s1.a = 123;
+    s1.b = 456;
+    s2.a = 0;
+    s2.b = 0;
+    printf("%d %d\n", s1.a, s1.b);
+    printf("%d %d\n", s2.a, s2.b);
+    s2 = s1;
+    printf("%d %d\n", s2.a, s2.b);
+}
+EOF
+
+cat <<'EOF' > expected
+42
+EOF
+test_diff <<'EOF'
+void* calloc();
+int printf();
+
+struct S {
+    int x;
+};
+typedef struct S S;
+
+int main() {
+    S* s = calloc(1, sizeof(S));
+    s->x = 42;
+    printf("%d\n", s->x);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+4
+EOF
+test_diff <<'EOF'
+struct S0;
+typedef struct S0 S0;
+
+struct S1 {
+    int x;
+};
+
+struct S2 {
+    int x;
+};
+
+struct S3 {
+    int x;
+};
+
+struct S4 {
+    int x;
+};
+
+struct S0 {
+    int x;
+};
+
+int printf(const char*, ...);
+int main() {
+    printf("%zu\n", sizeof(S0));
+}
+EOF
+
+cat <<'EOF' > expected
+8
+4
+4
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+typedef struct {
+    int x;
+    int y;
+} S;
+
+typedef union {
+    int a;
+    char b;
+} U;
+
+typedef enum {
+    RED,
+    GREEN,
+    BLUE
+} E;
+
+int main() {
+    printf("%zu\n", sizeof(S));
+    printf("%zu\n", sizeof(U));
+    printf("%zu\n", sizeof(E));
+}
+EOF
diff --git a/tests/ternary_operator.c b/tests/ternary_operator.c
deleted file mode 100644
index 1f46dbe..0000000
--- a/tests/ternary_operator.c
+++ /dev/null
@@ -1,6 +0,0 @@
-#include <helpers.h>
-
-int main() {
-    ASSERT_EQ(2, 1 ? 2 : 3);
-    ASSERT_EQ(5, 0 ? 4 : 5);
-}
diff --git a/tests/line_continuation.sh b/tests/tokenize.sh
index 89f4543..2db9640 100644
--- a/tests/line_continuation.sh
+++ b/tests/tokenize.sh
@@ -1,3 +1,47 @@
+# comments
+cat <<'EOF' > expected
+EOF
+test_diff <<'EOF'
+// TODO: check if the token is at the beginning of line.
+// TODO: check if skipped whitespaces do not contain line breaks.
+int main() {
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+EOF
+
+test_diff <<'EOF'
+/* lorem ipsum */
+/*
+lorem ipsum
+*/
+// /*
+/* /*
+ */
+int/**/main() {
+}
+EOF
+
+# identifiers
+cat <<'EOF' > expected
+42,123
+EOF
+test_diff <<'EOF'
+int printf();
+
+int main() {
+    int _a = 42;
+    int _b = 123;
+
+    printf("%d,%d\n", _a, _b);
+
+    return 0;
+}
+EOF
+
+# line continuation
 cat <<'EOF' > expected
 10 20
 100 300 500
@@ -54,3 +98,19 @@ test_diff < main_cr.c
 # Mixed
 printf 'int printf(const char*, ...);\nint main() {\r\n    printf("Hello World\\n");\r    printf("Line con\\\r\ntinues\\n");\n    return 0;\r\n}\r\n' > main_mixed.c
 test_diff < main_mixed.c
+
+# keywords
+cat <<'EOF' > expected
+
+
+int printf ();
+int main () {}
+EOF
+
+test_cpp <<'EOF'
+// A keyword is treated as a normal identifier in preprocessing phase.
+#define auto int
+
+auto printf();
+auto main() {}
+EOF
diff --git a/tests/typedef_struct.sh b/tests/typedef_struct.sh
deleted file mode 100644
index 593d903..0000000
--- a/tests/typedef_struct.sh
+++ /dev/null
@@ -1,84 +0,0 @@
-cat <<'EOF' > expected
-42
-EOF
-test_diff <<'EOF'
-void* calloc();
-int printf();
-
-struct S {
-    int x;
-};
-typedef struct S S;
-
-int main() {
-    S* s = calloc(1, sizeof(S));
-    s->x = 42;
-    printf("%d\n", s->x);
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-4
-EOF
-test_diff <<'EOF'
-struct S0;
-typedef struct S0 S0;
-
-struct S1 {
-    int x;
-};
-
-struct S2 {
-    int x;
-};
-
-struct S3 {
-    int x;
-};
-
-struct S4 {
-    int x;
-};
-
-struct S0 {
-    int x;
-};
-
-int printf(const char*, ...);
-int main() {
-    printf("%zu\n", sizeof(S0));
-}
-EOF
-
-cat <<'EOF' > expected
-8
-4
-4
-EOF
-
-test_diff <<'EOF'
-int printf();
-
-typedef struct {
-    int x;
-    int y;
-} S;
-
-typedef union {
-    int a;
-    char b;
-} U;
-
-typedef enum {
-    RED,
-    GREEN,
-    BLUE
-} E;
-
-int main() {
-    printf("%zu\n", sizeof(S));
-    printf("%zu\n", sizeof(U));
-    printf("%zu\n", sizeof(E));
-}
-EOF
diff --git a/tests/sizeof_operator.sh b/tests/types.sh
index c8df5da..892f85b 100644
--- a/tests/sizeof_operator.sh
+++ b/tests/types.sh
@@ -1,3 +1,22 @@
+# short type
+cat <<'EOF' > expected
+2 42
+8 123
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+int main() {
+    short a = 42;
+    printf("%zu %hd\n", sizeof(a), a);
+    short* b = &a;
+    *b = 123;
+    printf("%zu %hd\n", sizeof(b), *b);
+}
+EOF
+
+# sizeof operator
 cat <<'EOF' > expected
 sizeof(int) = 4
 sizeof(int*) = 8
@@ -174,3 +193,53 @@ int main() {
     return 0;
 }
 EOF
+
+# enums
+cat <<'EOF' > expected
+4
+0,1,2
+EOF
+test_diff <<'EOF'
+int printf();
+
+enum E {
+    A,
+    B,
+    C,
+};
+
+int main() {
+    enum E x = A;
+    printf("%d\n", sizeof(enum E));
+    printf("%d,%d,%d\n", A, B, C);
+    return 0;
+}
+EOF
+
+cat <<'EOF' > expected
+10,11,20,21
+0,5,6,6
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+enum E1 {
+    A = 10,
+    B,
+    C = 20,
+    D,
+};
+
+enum E2 {
+    E,
+    F = 5,
+    G,
+    H = G,
+};
+
+int main() {
+    printf("%d,%d,%d,%d\n", A, B, C, D);
+    printf("%d,%d,%d,%d\n", E, F, G, H);
+}
+EOF
diff --git a/tests/undef.sh b/tests/undef.sh
deleted file mode 100644
index 27d03c6..0000000
--- a/tests/undef.sh
+++ /dev/null
@@ -1,33 +0,0 @@
-cat <<'EOF' > expected
-int printf ();
-
-int main () {
-
- printf ( A is defined\n);
-
-
- printf ( A is undefined\n);
-}
-EOF
-
-test_cpp <<'EOF'
-int printf();
-
-int main() {
-#define A 1
-
-#ifdef A
-    printf("A is defined\n");
-#else
-    printf("A is undefined\n");
-#endif
-
-#undef A
-
-#ifdef A
-    printf("A is defined\n");
-#else
-    printf("A is undefined\n");
-#endif
-}
-EOF
diff --git a/tests/variables.c b/tests/variables.c
new file mode 100644
index 0000000..0bd2127
--- /dev/null
+++ b/tests/variables.c
@@ -0,0 +1,74 @@
+#include <helpers.h>
+
+int printf(const char*, ...);
+int strcmp(const char*, const char*);
+
+// global variables
+int g_a;
+int* g_b = &g_a;
+int g_c[10];
+int* g_d = g_c;
+int g_e, *g_f = g_e, g_g[10], *g_h = g_g;
+
+char g_i = 42;
+short g_j = 123;
+int g_k = 999;
+
+char g_l[6] = "hello";
+
+int main() {
+    // global variables
+    *g_b = 123;
+    ASSERT_EQ(123, g_a);
+
+    g_d[2] = 42;
+    ASSERT_EQ(42, g_c[2]);
+
+    *g_f = 456;
+    ASSERT_EQ(456, g_e);
+
+    g_h[5] = 789;
+    ASSERT_EQ(789, g_g[5]);
+
+    ASSERT_EQ(42, g_i);
+    ASSERT_EQ(123, g_j);
+    ASSERT_EQ(999, g_k);
+
+    ASSERT_EQ(0, strcmp("hello", g_l));
+
+    // local variables
+    int foo;
+    foo = 42;
+    ASSERT_EQ(42, foo);
+
+    int bar;
+    bar = 28;
+    ASSERT_EQ(70, foo + bar);
+
+    int a1;
+    int a2;
+    int a3;
+    int a4;
+    int a5;
+    int a6;
+    int a7;
+    int a8;
+    int a9;
+
+    a1 = 1;
+    a2 = 2;
+    a3 = 3;
+    a4 = 4;
+    a5 = 5;
+    a6 = 6;
+    a7 = 7;
+    a8 = 8;
+    a9 = 9;
+
+    ASSERT_EQ(45, a1 + a2 + a3 + a4 + a5 + a6 + a7 + a8 + a9 + 0);
+
+    int d = 2, e = d, f = d + e;
+    ASSERT_EQ(2, d);
+    ASSERT_EQ(2, e);
+    ASSERT_EQ(4, f);
+}
diff --git a/tests/variadic_functions.sh b/tests/variadic_functions.sh
deleted file mode 100644
index 155fc1a..0000000
--- a/tests/variadic_functions.sh
+++ /dev/null
@@ -1,51 +0,0 @@
-cat <<'EOF' > expected
-123
-456 789
-EOF
-
-test_diff <<'EOF'
-#include <stdarg.h>
-
-int fprintf();
-
-struct FILE;
-typedef struct FILE FILE;
-
-extern FILE* stdout;
-
-int vfprintf(FILE*, const char*, va_list);
-
-void fatal_error(const char* msg, ...) {
-    va_list args;
-    va_start(args, msg);
-    vfprintf(stdout, msg, args);
-    va_end(args);
-    fprintf(stdout, "\n");
-}
-
-int main() {
-    fatal_error("%d", 123);
-    fatal_error("%d %d", 456, 789);
-    return 0;
-}
-EOF
-
-test_exit_code 0 <<'EOF'
-#include <stdarg.h>
-#include <helpers.h>
-
-int sum(int n, ...) {
-    va_list args;
-    va_start(args, n);
-    int s = 0;
-    for (int i = 0; i < n; ++i) {
-        s += va_arg(args, int);
-    }
-    va_end(args);
-    return s;
-}
-
-int main() {
-    ASSERT_EQ(400, sum(5, 100, 90, 80, 70, 60));
-}
-EOF
diff --git a/tests/void_functions.sh b/tests/void_functions.sh
deleted file mode 100644
index 656c2c1..0000000
--- a/tests/void_functions.sh
+++ /dev/null
@@ -1,48 +0,0 @@
-cat <<'EOF' > expected
-123
-EOF
-test_diff <<'EOF'
-int printf();
-
-void foo_bar(int hoge_piyo) {
-    printf("%d\n", hoge_piyo);
-}
-
-int main() {
-    foo_bar(123);
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-EOF
-test_diff <<'EOF'
-struct S {
-    int a;
-};
-
-struct S* f();
-
-struct S* g() {}
-
-int main() {
-    return 0;
-}
-EOF
-
-cat <<'EOF' > expected
-hi
-EOF
-test_diff <<'EOF'
-int printf();
-
-void f() {
-    printf("hi\n");
-    return;
-}
-
-int main() {
-    f();
-    return 0;
-}
-EOF