X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=compiler%2Frustc_lint_defs%2Fsrc%2Fbuiltin.rs;h=ba8a8c3d8c993cc036270771d061417c0045d0de;hb=d837c00d1008c2ab13bf80117b81f5e482fc9edb;hp=f95d4a6ca54812b2efb33dce2d2ad6a46ae9dd72;hpb=c38111c4fb9c22a36f9a9195d1884052bb670af2;p=rust.git

diff --git a/compiler/rustc_lint_defs/src/builtin.rs b/compiler/rustc_lint_defs/src/builtin.rs
index f95d4a6ca54..ba8a8c3d8c9 100644
--- a/compiler/rustc_lint_defs/src/builtin.rs
+++ b/compiler/rustc_lint_defs/src/builtin.rs
@@ -6,7 +6,7 @@
 //! compiler code, rather than using their own custom pass. Those
 //! lints are all available in `rustc_lint::builtin`.
 
-use crate::{declare_lint, declare_lint_pass, FutureBreakage};
+use crate::{declare_lint, declare_lint_pass, FutureBreakage, FutureIncompatibilityReason};
 use rustc_span::edition::Edition;
 
 declare_lint! {
@@ -41,7 +41,6 @@
     "applying forbid to lint-groups",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #81670 <https://github.com/rust-lang/rust/issues/81670>",
-        edition: None,
     };
 }
 
@@ -77,7 +76,6 @@
     "ill-formed attribute inputs that were previously accepted and used in practice",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #57571 <https://github.com/rust-lang/rust/issues/57571>",
-        edition: None,
     };
     crate_level_only
 }
@@ -114,7 +112,6 @@
     "conflicts between `#[repr(..)]` hints that were previously accepted and used in practice",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #68585 <https://github.com/rust-lang/rust/issues/68585>",
-        edition: None,
     };
 }
 
@@ -293,7 +290,6 @@
     "constant evaluation encountered erroneous expression",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #71800 <https://github.com/rust-lang/rust/issues/71800>",
-        edition: None,
     };
     report_in_external_macro
 }
@@ -900,7 +896,6 @@
     "detect private items in public interfaces not caught by the old implementation",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #34537 <https://github.com/rust-lang/rust/issues/34537>",
-        edition: None,
     };
 }
 
@@ -980,7 +975,6 @@
     "detect public re-exports of private extern crates",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #34537 <https://github.com/rust-lang/rust/issues/34537>",
-        edition: None,
     };
 }
 
@@ -1010,7 +1004,6 @@
     "type parameter default erroneously allowed in invalid location",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #36887 <https://github.com/rust-lang/rust/issues/36887>",
-        edition: None,
     };
 }
 
@@ -1078,7 +1071,6 @@
     "detects unaligned references to fields of packed structs",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #82523 <https://github.com/rust-lang/rust/issues/82523>",
-        edition: None,
     };
     report_in_external_macro
 }
@@ -1200,7 +1192,6 @@
     "patterns in functions without body were erroneously allowed",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #35203 <https://github.com/rust-lang/rust/issues/35203>",
-        edition: None,
     };
 }
 
@@ -1244,7 +1235,6 @@
     "detects missing fragment specifiers in unused `macro_rules!` patterns",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #40107 <https://github.com/rust-lang/rust/issues/40107>",
-        edition: None,
     };
 }
 
@@ -1286,7 +1276,6 @@
     "detects generic lifetime arguments in path segments with late bound lifetime parameters",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #42868 <https://github.com/rust-lang/rust/issues/42868>",
-        edition: None,
     };
 }
 
@@ -1322,7 +1311,6 @@
     "trait-object types were treated as different depending on marker-trait order",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #56484 <https://github.com/rust-lang/rust/issues/56484>",
-        edition: None,
     };
 }
 
@@ -1362,7 +1350,6 @@
     "distinct impls distinguished only by the leak-check code",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #56105 <https://github.com/rust-lang/rust/issues/56105>",
-        edition: None,
     };
 }
 
@@ -1554,7 +1541,7 @@
     "raw pointer to an inference variable",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #46906 <https://github.com/rust-lang/rust/issues/46906>",
-        edition: Some(Edition::Edition2018),
+        reason: FutureIncompatibilityReason::EditionError(Edition::Edition2018),
     };
 }
 
@@ -1621,7 +1608,7 @@
     "suggest using `dyn Trait` for trait objects",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #80165 <https://github.com/rust-lang/rust/issues/80165>",
-        edition: Some(Edition::Edition2021),
+        reason: FutureIncompatibilityReason::EditionError(Edition::Edition2021),
     };
 }
 
@@ -1676,7 +1663,7 @@
      instead of `crate`, `self`, or an extern crate name",
      @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #53130 <https://github.com/rust-lang/rust/issues/53130>",
-        edition: Some(Edition::Edition2018),
+        reason: FutureIncompatibilityReason::EditionError(Edition::Edition2018),
      };
 }
 
@@ -1725,7 +1712,6 @@
     "floating-point literals cannot be used in patterns",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #41620 <https://github.com/rust-lang/rust/issues/41620>",
-        edition: None,
     };
 }
 
@@ -1769,7 +1755,6 @@
     "detects name collision with an existing but unstable method",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #48919 <https://github.com/rust-lang/rust/issues/48919>",
-        edition: None,
         // Note: this item represents future incompatibility of all unstable functions in the
         //       standard library, and thus should never be removed or changed to an error.
     };
@@ -1873,7 +1858,6 @@
     "checks the object safety of where clauses",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #51443 <https://github.com/rust-lang/rust/issues/51443>",
-        edition: None,
     };
 }
 
@@ -1940,7 +1924,6 @@
     "detects proc macro derives using inaccessible names from parent modules",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #83583 <https://github.com/rust-lang/rust/issues/83583>",
-        edition: None,
     };
 }
 
@@ -2043,7 +2026,6 @@
      cannot be referred to by absolute paths",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #52234 <https://github.com/rust-lang/rust/issues/52234>",
-        edition: None,
     };
     crate_level_only
 }
@@ -2134,7 +2116,6 @@
     "constant used in pattern contains value of non-structural-match type in a field or a variant",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #62411 <https://github.com/rust-lang/rust/issues/62411>",
-        edition: None,
     };
 }
 
@@ -2190,7 +2171,6 @@
     "pointers are not structural-match",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #62411 <https://github.com/rust-lang/rust/issues/70861>",
-        edition: None,
     };
 }
 
@@ -2229,7 +2209,6 @@
     expression contains values of non-structural-match types",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #73448 <https://github.com/rust-lang/rust/issues/73448>",
-        edition: None,
     };
 }
 
@@ -2287,7 +2266,6 @@
     "ambiguous associated items",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #57644 <https://github.com/rust-lang/rust/issues/57644>",
-        edition: None,
     };
 }
 
@@ -2318,7 +2296,6 @@
     "reservation of a two-phased borrow conflicts with other shared borrows",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #59159 <https://github.com/rust-lang/rust/issues/59159>",
-        edition: None,
     };
 }
 
@@ -2360,7 +2337,6 @@
     "a feature gate that doesn't break dependent crates",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #64266 <https://github.com/rust-lang/rust/issues/64266>",
-        edition: None,
     };
 }
 
@@ -2589,7 +2565,6 @@
     "a C-like enum implementing Drop is cast",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #73333 <https://github.com/rust-lang/rust/issues/73333>",
-        edition: None,
     };
 }
 
@@ -2629,7 +2604,6 @@
     "detects a generic constant is used in a type without a emitting a warning",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #76200 <https://github.com/rust-lang/rust/issues/76200>",
-        edition: None,
     };
 }
 
@@ -2688,7 +2662,6 @@
     "uninhabited static",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #74840 <https://github.com/rust-lang/rust/issues/74840>",
-        edition: None,
     };
 }
 
@@ -2758,7 +2731,6 @@
     "unsupported naked function definitions",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #32408 <https://github.com/rust-lang/rust/issues/32408>",
-        edition: None,
     };
 }
 
@@ -2831,7 +2803,6 @@
     "trailing semicolon in macro body used as expression",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #79813 <https://github.com/rust-lang/rust/issues/79813>",
-        edition: None,
     };
 }
 
@@ -3001,6 +2972,8 @@
         PROC_MACRO_BACK_COMPAT,
         OR_PATTERNS_BACK_COMPAT,
         LARGE_ASSIGNMENTS,
+        FUTURE_PRELUDE_COLLISION,
+        RESERVED_PREFIX,
     ]
 }
 
@@ -3153,7 +3126,6 @@
     "detects invalid `#[doc(...)]` attributes",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #82730 <https://github.com/rust-lang/rust/issues/82730>",
-        edition: None,
     };
 }
 
@@ -3200,7 +3172,6 @@
     "detects usage of old versions of certain proc-macro crates",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #83125 <https://github.com/rust-lang/rust/issues/83125>",
-        edition: None,
         future_breakage: Some(FutureBreakage {
             date: None
         })
@@ -3241,6 +3212,91 @@
     "detects usage of old versions of or-patterns",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #84869 <https://github.com/rust-lang/rust/issues/84869>",
+        reason: FutureIncompatibilityReason::EditionError(Edition::Edition2021),
+    };
+}
+
+declare_lint! {
+    /// The `future_prelude_collision` lint detects the usage of trait methods which are ambiguous
+    /// with traits added to the prelude in future editions.
+    ///
+    /// ### Example
+    ///
+    /// ```rust,compile_fail
+    /// #![deny(future_prelude_collision)]
+    ///
+    /// trait Foo {
+    ///     fn try_into(self) -> Result<String, !>;
+    /// }
+    ///
+    /// impl Foo for &str {
+    ///     fn try_into(self) -> Result<String, !> {
+    ///         Ok(String::from(self))
+    ///     }
+    /// }
+    ///
+    /// fn main() {
+    ///     let x: String = "3".try_into().unwrap();
+    ///     //                  ^^^^^^^^
+    ///     // This call to try_into matches both Foo:try_into and TryInto::try_into as
+    ///     // `TryInto` has been added to the Rust prelude in 2021 edition.
+    ///     println!("{}", x);
+    /// }
+    /// ```
+    ///
+    /// {{produces}}
+    ///
+    /// ### Explanation
+    ///
+    /// In Rust 2021, one of the important introductions is the [prelude changes], which add
+    /// `TryFrom`, `TryInto`, and `FromIterator` into the standard library's prelude. Since this
+    /// results in an ambiguity as to which method/function to call when an existing `try_into`
+    ///  method is called via dot-call syntax or a `try_from`/`from_iter` associated function
+    ///  is called directly on a type.
+    ///
+    /// [prelude changes]: https://blog.rust-lang.org/inside-rust/2021/03/04/planning-rust-2021.html#prelude-changes
+    pub FUTURE_PRELUDE_COLLISION,
+    Allow,
+    "detects the usage of trait methods which are ambiguous with traits added to the \
+        prelude in future editions",
+    @future_incompatible = FutureIncompatibleInfo {
+        reference: "issue #85684 <https://github.com/rust-lang/rust/issues/85684>",
+        reason: FutureIncompatibilityReason::EditionError(Edition::Edition2021),
+    };
+}
+
+declare_lint! {
+    /// The `reserved_prefix` lint detects identifiers that will be parsed as a
+    /// prefix instead in Rust 2021.
+    ///
+    /// ### Example
+    ///
+    /// ```rust,compile_fail
+    /// #![deny(reserved_prefix)]
+    ///
+    /// macro_rules! m {
+    ///     (z $x:expr) => ();
+    /// }
+    ///
+    /// m!(z"hey");
+    /// ```
+    ///
+    /// {{produces}}
+    ///
+    /// ### Explanation
+    ///
+    /// In Rust 2015 and 2018, `z"hey"` is two tokens: the identifier `z`
+    /// followed by the string literal `"hey"`. In Rust 2021, the `z` is
+    /// considered a prefix for `"hey"`.
+    ///
+    /// This lint suggests to add whitespace between the `z` and `"hey"` tokens
+    /// to keep them separated in Rust 2021.
+    pub RESERVED_PREFIX,
+    Allow,
+    "identifiers that will be parsed as a prefix in Rust 2021",
+    @future_incompatible = FutureIncompatibleInfo {
+        reference: "issue #84978 <https://github.com/rust-lang/rust/issues/84978>",
         edition: Some(Edition::Edition2021),
     };
+    crate_level_only
 }