Differentiate between cargo and non-cargo runs

Author: estebank

compiler/rustc_resolve/src/diagnostics.rs

@@ -24,6 +24,7 @@ use rustc_session::lint::builtin::{
     MACRO_EXPANDED_MACRO_EXPORTS_ACCESSED_BY_ABSOLUTE_PATHS,
 };
 use rustc_session::lint::{AmbiguityErrorDiag, BuiltinLintDiag};
+use rustc_session::utils::was_invoked_from_cargo;
 use rustc_span::edit_distance::find_best_match_for_name;
 use rustc_span::edition::Edition;
 use rustc_span::hygiene::MacroKind;
@@ -2045,10 +2046,17 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
                             self.current_crate_outer_attr_insert_span,
                             format!("extern crate {ident};\n"),
                         )],
-                        format!(
-                            "if you wanted to use a crate named `{ident}`, use `cargo add {ident}` \
-                            to add it to your `Cargo.toml` and import it in your code",
-                        ),
+                        if was_invoked_from_cargo() {
+                            format!(
+                                "if you wanted to use a crate named `{ident}`, use `cargo add {ident}` \
+                             to add it to your `Cargo.toml` and import it in your code",
+                            )
+                        } else {
+                            format!(
+                                "you might be missing a crate named `{ident}`, add it to your \
+                                 project and import it in your code",
+                            )
+                        },
                         Applicability::MaybeIncorrect,
                     )),
                 )
@@ -2227,14 +2235,24 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
                 let descr = binding.res().descr();
                 (format!("{descr} `{ident}` is not a crate or module"), suggestion)
             } else {
-                let suggestion = suggestion.or(Some((
-                    vec![],
-                    format!(
-                        "if you wanted to use a crate named `{ident}`, use `cargo add {ident}` to \
-                         add it to your `Cargo.toml`",
-                    ),
-                    Applicability::MaybeIncorrect,
-                )));
+                let suggestion = if suggestion.is_some() {
+                    suggestion
+                } else if was_invoked_from_cargo() {
+                    Some((
+                        vec![],
+                        format!(
+                            "if you wanted to use a crate named `{ident}`, use `cargo add {ident}` \
+                             to add it to your `Cargo.toml`",
+                        ),
+                        Applicability::MaybeIncorrect,
+                    ))
+                } else {
+                    Some((
+                        vec![],
+                        format!("you might be missing a crate named `{ident}`",),
+                        Applicability::MaybeIncorrect,
+                    ))
+                };
                 (format!("use of unresolved module or unlinked crate `{ident}`"), suggestion)
             }
         }

tests/ui/attributes/field-attributes-vis-unresolved.stderr

@@ -4,7 +4,7 @@ error[E0433]: failed to resolve: use of unresolved module or unlinked crate `non
 LL |     pub(in nonexistent) field: u8
    |            ^^^^^^^^^^^ use of unresolved module or unlinked crate `nonexistent`
    |
-help: if you wanted to use a crate named `nonexistent`, use `cargo add nonexistent` to add it to your `Cargo.toml` and import it in your code
+help: you might be missing a crate named `nonexistent`, add it to your project and import it in your code
    |
 LL + extern crate nonexistent;
    |
@@ -15,7 +15,7 @@ error[E0433]: failed to resolve: use of unresolved module or unlinked crate `non
 LL |     pub(in nonexistent) u8
    |            ^^^^^^^^^^^ use of unresolved module or unlinked crate `nonexistent`
    |
-help: if you wanted to use a crate named `nonexistent`, use `cargo add nonexistent` to add it to your `Cargo.toml` and import it in your code
+help: you might be missing a crate named `nonexistent`, add it to your project and import it in your code
    |
 LL + extern crate nonexistent;
    |

tests/ui/coherence/conflicting-impl-with-err.stderr

@@ -4,15 +4,15 @@ error[E0433]: failed to resolve: use of unresolved module or unlinked crate `nop
 LL | impl From<nope::Thing> for Error {
    |           ^^^^ use of unresolved module or unlinked crate `nope`
    |
-   = help: if you wanted to use a crate named `nope`, use `cargo add nope` to add it to your `Cargo.toml`
+   = help: you might be missing a crate named `nope`
 
 error[E0433]: failed to resolve: use of unresolved module or unlinked crate `nope`
   --> $DIR/conflicting-impl-with-err.rs:5:16
    |
 LL |     fn from(_: nope::Thing) -> Self {
    |                ^^^^ use of unresolved module or unlinked crate `nope`
    |
-   = help: if you wanted to use a crate named `nope`, use `cargo add nope` to add it to your `Cargo.toml`
+   = help: you might be missing a crate named `nope`
 
 error: aborting due to 2 previous errors
 

tests/ui/delegation/bad-resolve.stderr

@@ -87,7 +87,7 @@ error[E0433]: failed to resolve: use of unresolved module or unlinked crate `unr
 LL | reuse unresolved_prefix::{a, b, c};
    |       ^^^^^^^^^^^^^^^^^ use of unresolved module or unlinked crate `unresolved_prefix`
    |
-   = help: if you wanted to use a crate named `unresolved_prefix`, use `cargo add unresolved_prefix` to add it to your `Cargo.toml`
+   = help: you might be missing a crate named `unresolved_prefix`
 
 error[E0433]: failed to resolve: `crate` in paths can only be used in start position
   --> $DIR/bad-resolve.rs:44:29

tests/ui/error-codes/E0432.stderr

@@ -4,7 +4,7 @@ error[E0432]: unresolved import `something`
 LL | use something::Foo;
    |     ^^^^^^^^^ use of unresolved module or unlinked crate `something`
    |
-help: if you wanted to use a crate named `something`, use `cargo add something` to add it to your `Cargo.toml` and import it in your code
+help: you might be missing a crate named `something`, add it to your project and import it in your code
    |
 LL + extern crate something;
    |

tests/ui/extern-flag/multiple-opts.stderr

@@ -4,7 +4,7 @@ error[E0433]: failed to resolve: use of unresolved module or unlinked crate `som
 LL |     somedep::somefun();
    |     ^^^^^^^ use of unresolved module or unlinked crate `somedep`
    |
-   = help: if you wanted to use a crate named `somedep`, use `cargo add somedep` to add it to your `Cargo.toml`
+   = help: you might be missing a crate named `somedep`
 
 error: aborting due to 1 previous error
 

tests/ui/extern-flag/noprelude.stderr

@@ -4,7 +4,7 @@ error[E0433]: failed to resolve: use of unresolved module or unlinked crate `som
 LL |     somedep::somefun();
    |     ^^^^^^^ use of unresolved module or unlinked crate `somedep`
    |
-   = help: if you wanted to use a crate named `somedep`, use `cargo add somedep` to add it to your `Cargo.toml`
+   = help: you might be missing a crate named `somedep`
 
 error: aborting due to 1 previous error
 

tests/ui/foreign/stashed-issue-121451.stderr

@@ -4,7 +4,7 @@ error[E0433]: failed to resolve: use of unresolved module or unlinked crate `lib
 LL | extern "C" fn _f() -> libc::uintptr_t {}
    |                       ^^^^ use of unresolved module or unlinked crate `libc`
    |
-   = help: if you wanted to use a crate named `libc`, use `cargo add libc` to add it to your `Cargo.toml`
+   = help: you might be missing a crate named `libc`
 
 error: aborting due to 1 previous error
 

tests/ui/hygiene/extern-prelude-from-opaque-fail-2018.stderr

@@ -24,7 +24,7 @@ LL |         fn f() { my_core::mem::drop(0); }
 LL | a!();
    | ---- in this macro invocation
    |
-   = help: if you wanted to use a crate named `my_core`, use `cargo add my_core` to add it to your `Cargo.toml`
+   = help: you might be missing a crate named `my_core`
    = help: consider importing this module:
            std::mem
    = note: this error originates in the macro `a` (in Nightly builds, run with -Z macro-backtrace for more info)
@@ -35,7 +35,7 @@ error[E0433]: failed to resolve: use of unresolved module or unlinked crate `my_
 LL |     fn f() { my_core::mem::drop(0); }
    |              ^^^^^^^ use of unresolved module or unlinked crate `my_core`
    |
-   = help: if you wanted to use a crate named `my_core`, use `cargo add my_core` to add it to your `Cargo.toml`
+   = help: you might be missing a crate named `my_core`
 help: consider importing this module
    |
 LL +     use std::mem;

tests/ui/hygiene/extern-prelude-from-opaque-fail.stderr

@@ -24,7 +24,7 @@ LL |         fn f() { my_core::mem::drop(0); }
 LL | a!();
    | ---- in this macro invocation
    |
-   = help: if you wanted to use a crate named `my_core`, use `cargo add my_core` to add it to your `Cargo.toml`
+   = help: you might be missing a crate named `my_core`
    = help: consider importing this module:
            my_core::mem
    = note: this error originates in the macro `a` (in Nightly builds, run with -Z macro-backtrace for more info)
@@ -35,7 +35,7 @@ error[E0433]: failed to resolve: use of unresolved module or unlinked crate `my_
 LL |     fn f() { my_core::mem::drop(0); }
    |              ^^^^^^^ use of unresolved module or unlinked crate `my_core`
    |
-   = help: if you wanted to use a crate named `my_core`, use `cargo add my_core` to add it to your `Cargo.toml`
+   = help: you might be missing a crate named `my_core`
 help: consider importing this module
    |
 LL +     use my_core::mem;