tests/ui/proc-macro/expand-expr.rs

   1 // aux-build:expand-expr.rs
   2 // no-remap-src-base: check_expand_expr_file!() fails when enabled.
   3
   4 #![feature(concat_bytes)]
   5 extern crate expand_expr;
   6
   7 use expand_expr::{
   8     check_expand_expr_file, echo_pm, expand_expr_fail, expand_expr_is, recursive_expand,
   9 };
  10
  11 // Check builtin macros can be expanded.
  12
  13 expand_expr_is!(13u32, line!());
  14 expand_expr_is!(24u32, column!());
  15
  16 expand_expr_is!("Hello, World!", concat!("Hello, ", "World", "!"));
  17 expand_expr_is!("int10floats5.3booltrue", concat!("int", 10, "floats", 5.3, "bool", true));
  18 expand_expr_is!("Hello", concat!(r##"Hello"##));
  19
  20 expand_expr_is!("Included file contents\n", include_str!("auxiliary/included-file.txt"));
  21 expand_expr_is!(b"Included file contents\n", include_bytes!("auxiliary/included-file.txt"));
  22
  23 expand_expr_is!(
  24     "contents: Included file contents\n",
  25     concat!("contents: ", include_str!("auxiliary/included-file.txt"))
  26 );
  27
  28 expand_expr_is!(
  29     b"contents: Included file contents\n",
  30     concat_bytes!(b"contents: ", include_bytes!("auxiliary/included-file.txt"))
  31 );
  32
  33 // Correct value is checked for multiple sources.
  34 check_expand_expr_file!(file!());
  35
  36 expand_expr_is!("hello", stringify!(hello));
  37 expand_expr_is!("10 + 20", stringify!(10 + 20));
  38
  39 macro_rules! echo_tts {
  40     ($($t:tt)*) => { $($t)* };  //~ ERROR: expected expression, found `$`
  41 }
  42
  43 macro_rules! echo_lit {
  44     ($l:literal) => {
  45         $l
  46     };
  47 }
  48
  49 macro_rules! echo_expr {
  50     ($e:expr) => {
  51         $e
  52     };
  53 }
  54
  55 macro_rules! simple_lit {
  56     ($l:literal) => {
  57         expand_expr_is!($l, $l);
  58         expand_expr_is!($l, echo_lit!($l));
  59         expand_expr_is!($l, echo_expr!($l));
  60         expand_expr_is!($l, echo_tts!($l));
  61         expand_expr_is!($l, echo_pm!($l));
  62         const _: () = {
  63             macro_rules! mac {
  64                 () => {
  65                     $l
  66                 };
  67             }
  68             expand_expr_is!($l, mac!());
  69             expand_expr_is!($l, echo_expr!(mac!()));
  70             expand_expr_is!($l, echo_tts!(mac!()));
  71             expand_expr_is!($l, echo_pm!(mac!()));
  72         };
  73     };
  74 }
  75
  76 simple_lit!("Hello, World");
  77 simple_lit!('c');
  78 simple_lit!(b'c');
  79 simple_lit!(10);
  80 simple_lit!(10.0);
  81 simple_lit!(10.0f64);
  82 simple_lit!(-3.14159);
  83 simple_lit!(-3.5e10);
  84 simple_lit!(0xFEED);
  85 simple_lit!(-0xFEED);
  86 simple_lit!(0b0100);
  87 simple_lit!(-0b0100);
  88 simple_lit!("string");
  89 simple_lit!(r##"raw string"##);
  90 simple_lit!(b"byte string");
  91 simple_lit!(br##"raw byte string"##);
  92 simple_lit!(true);
  93 simple_lit!(false);
  94
  95 // Ensure char escapes aren't normalized by expansion
  96 simple_lit!("\u{0}");
  97 simple_lit!("\0");
  98 simple_lit!("\x00");
  99 simple_lit!('\u{0}');
 100 simple_lit!('\0');
 101 simple_lit!('\x00');
 102 simple_lit!(b"\x00");
 103 simple_lit!(b"\0");
 104 simple_lit!(b'\x00');
 105 simple_lit!(b'\0');
 106
 107 // Extra tokens after the string literal aren't ignored
 108 expand_expr_fail!("string"; hello); //~ ERROR: expected one of `.`, `?`, or an operator, found `;`
 109
 110 // Invalid expressions produce errors in addition to returning `Err(())`.
 111 expand_expr_fail!($); //~ ERROR: expected expression, found `$`
 112 expand_expr_fail!(echo_tts!($));
 113 expand_expr_fail!(echo_pm!($)); //~ ERROR: expected expression, found `$`
 114
 115 // We get errors reported and recover during macro expansion if the macro
 116 // doesn't produce a valid expression.
 117 expand_expr_is!("string", echo_tts!("string"; hello)); //~ ERROR: macro expansion ignores token `hello` and any following
 118 expand_expr_is!("string", echo_pm!("string"; hello)); //~ ERROR: macro expansion ignores token `;` and any following
 119
 120 // For now, fail if a non-literal expression is expanded.
 121 expand_expr_fail!(arbitrary_expression() + "etc");
 122 expand_expr_fail!(echo_tts!(arbitrary_expression() + "etc"));
 123 expand_expr_fail!(echo_expr!(arbitrary_expression() + "etc"));
 124 expand_expr_fail!(echo_pm!(arbitrary_expression() + "etc"));
 125
 126 const _: u32 = recursive_expand!(); //~ ERROR: recursion limit reached while expanding `recursive_expand!`
 127
 128 fn main() {
 129     // https://github.com/rust-lang/rust/issues/104414
 130     match b"Included file contents\n" {
 131         include_bytes!("auxiliary/included-file.txt") => (),
 132         _ => panic!("include_bytes! in pattern"),
 133     }
 134 }