Add test for new proc_macro literal methods

Author: GuillaumeGomez

library/literal-escaper/README.md

@@ -1,4 +1,4 @@
 # literal-escaper
 
 This crate provides code to unescape string literals. It is used by `rustc_lexer`
-and `proc-macro`.
+and `proc_macro`.

library/proc_macro/src/lib.rs

@@ -61,6 +61,7 @@ use crate::escape::{EscapeOptions, escape_bytes};
 
 /// Errors returned when trying to retrieve a literal unescaped value.
 #[unstable(feature = "proc_macro_value", issue = "136652")]
+#[derive(Debug, PartialEq, Eq)]
 pub enum ConversionErrorKind {
     /// The literal failed to be escaped, take a look at [`EscapeError`] for more information.
     FailedToUnescape(EscapeError),

tests/ui/proc-macro/auxiliary/api/literal.rs

@@ -1,10 +1,11 @@
 // ignore-tidy-linelength
 
-use proc_macro::Literal;
+use proc_macro::{ConversionErrorKind, Literal};
 
 pub fn test() {
     test_display_literal();
     test_parse_literal();
+    test_str_value_methods();
 }
 
 fn test_display_literal() {
@@ -81,3 +82,53 @@ fn test_parse_literal() {
     assert!("- 10".parse::<Literal>().is_err());
     assert!("-'x'".parse::<Literal>().is_err());
 }
+
+fn test_str_value_methods() {
+    // Testing `str_value`
+    let lit = "\"\n\"".parse::<Literal>().unwrap();
+    assert_eq!(lit.str_value(), Ok("\n".to_string()));
+
+    let lit = "r#\"\n\"#".parse::<Literal>().unwrap();
+    assert_eq!(lit.str_value(), Ok("\n".to_string()));
+
+    let lit = "1".parse::<Literal>().unwrap();
+    assert_eq!(lit.str_value(), Err(ConversionErrorKind::InvalidLiteralKind));
+
+    let lit = "b\"\n\"".parse::<Literal>().unwrap();
+    assert_eq!(lit.str_value(), Err(ConversionErrorKind::InvalidLiteralKind));
+
+    let lit = "c\"\n\"".parse::<Literal>().unwrap();
+    assert_eq!(lit.str_value(), Err(ConversionErrorKind::InvalidLiteralKind));
+
+    // Testing `cstr_value`
+    let lit = "\"\n\"".parse::<Literal>().unwrap();
+    assert_eq!(lit.cstr_value(), Err(ConversionErrorKind::InvalidLiteralKind));
+
+    let lit = "r#\"\n\"#".parse::<Literal>().unwrap();
+    assert_eq!(lit.cstr_value(), Err(ConversionErrorKind::InvalidLiteralKind));
+
+    let lit = "1".parse::<Literal>().unwrap();
+    assert_eq!(lit.cstr_value(), Err(ConversionErrorKind::InvalidLiteralKind));
+
+    let lit = "b\"\n\"".parse::<Literal>().unwrap();
+    assert_eq!(lit.cstr_value(), Err(ConversionErrorKind::InvalidLiteralKind));
+
+    let lit = "c\"\n\"".parse::<Literal>().unwrap();
+    assert_eq!(lit.cstr_value(), Ok(vec![b'\n', 0]));
+
+    // Testing `byte_str_value`
+    let lit = "\"\n\"".parse::<Literal>().unwrap();
+    assert_eq!(lit.byte_str_value(), Err(ConversionErrorKind::InvalidLiteralKind));
+
+    let lit = "r#\"\n\"#".parse::<Literal>().unwrap();
+    assert_eq!(lit.byte_str_value(), Err(ConversionErrorKind::InvalidLiteralKind));
+
+    let lit = "1".parse::<Literal>().unwrap();
+    assert_eq!(lit.byte_str_value(), Err(ConversionErrorKind::InvalidLiteralKind));
+
+    let lit = "b\"\n\"".parse::<Literal>().unwrap();
+    assert_eq!(lit.byte_str_value(), Ok(vec![b'\n']));
+
+    let lit = "c\"\n\"".parse::<Literal>().unwrap();
+    assert_eq!(lit.byte_str_value(), Err(ConversionErrorKind::InvalidLiteralKind));
+}

tests/ui/proc-macro/auxiliary/api/proc_macro_api_tests.rs

@@ -1,6 +1,7 @@
 //@ edition: 2021
 
 #![feature(proc_macro_span)]
+#![feature(proc_macro_value)]
 #![deny(dead_code)] // catch if a test function is never called
 
 extern crate proc_macro;