feat(profile): Add built-in profile debug

Key points:
- It inherits from `dev`
  - Conceptually, debugging is part of the development process
  - The hope is this will smooth out the transition for people
- `cargo install --debug` now uses `debug` instead of `dev`
- `debug` changes nothing from `dev` right now.
  `dev` will evolve in the future
  (with `debug` overriding those values to leave it effectively unchanged)
  but that is deferred out to offer a transition period where `debug`
  can be used without but isn't required for debugging as people deal
  with multiple Rust versions. This also shrinks the change and
  decouples what the conversation around what the settings should be.

Author: epage

crates/cargo-util-schemas/src/restricted_names.rs

@@ -137,14 +137,6 @@ pub(crate) fn validate_profile_name(name: &str) -> Result<()> {
     }
 
     let lower_name = name.to_lowercase();
-    if lower_name == "debug" {
-        return Err(ErrorKind::ProfileNameReservedKeyword {
-            name: name.into(),
-            help: "To configure the default development profile, \
-                use the name `dev` as in [profile.dev]",
-        }
-        .into());
-    }
     if lower_name == "build-override" {
         return Err(ErrorKind::ProfileNameReservedKeyword {
             name: name.into(),

doc/book/src/commands/cargo-bench.md

@@ -46,8 +46,8 @@ function to handle running benchmarks.
 
 By default, `cargo bench` uses the [`bench` profile], which enables
 optimizations and disables debugging information. If you need to debug a
-benchmark, you can use the `--profile=dev` command-line option to switch to
-the dev profile. You can then run the debug-enabled benchmark within a
+benchmark, you can use the `--profile=debug` command-line option to switch to
+the debug profile. You can then run the debug-enabled benchmark within a
 debugger.
 
 [`bench` profile]: ../reference/profiles.html#bench

doc/book/src/commands/cargo-install.md

@@ -260,7 +260,7 @@ is specified.</p>
 
 
 <dt class="option-term" id="option-cargo-install---debug"><a class="option-anchor" href="#option-cargo-install---debug"><code>--debug</code></a></dt>
-<dd class="option-desc"><p>Build with the <code>dev</code> profile instead of the <code>release</code> profile.
+<dd class="option-desc"><p>Build with the <code>debug</code> profile instead of the <code>release</code> profile.
 See also the <code>--profile</code> option for choosing a specific profile by name.</p>
 </dd>
 

doc/book/src/commands/cargo-test.md

@@ -38,7 +38,10 @@ manifest settings, in which case your code will need to provide its own `main`
 function to handle running tests.
 
 By default, `cargo test` uses the [`test` profile], which enables
-debugging.
+some optimizations and disables debugging information for fast feedback. If you need to debug a
+test, you can use the `--profile=debug` command-line option to switch to
+the debug profile. You can then run the debug-enabled test within a
+debugger.
 
 [`test` profile]: ../reference/profiles.html#test
 

doc/book/src/reference/profiles.md

@@ -262,8 +262,8 @@ whether or not [`rpath`] is enabled.
 
 ### dev
 
-The `dev` profile is used for normal development and debugging. It is the
-default for build commands like [`cargo build`], and is used for `cargo install --debug`.
+The `dev` profile is used for normal development. It is the
+default for build commands like [`cargo build`], and is used for `cargo install --profile dev`.
 
 The default settings for the `dev` profile are:
 
@@ -282,6 +282,17 @@ codegen-units = 256
 rpath = false
 ```
 
+### debug
+
+The `debug` profile is used for creating binaries to run with a debugger. It is used with `cargo build --profile debug` and `cargo install --debug`.
+
+The default settings for the `debug` profile are:
+
+```toml
+[profile.debug]
+inherits = "dev"
+```
+
 ### release
 
 The `release` profile is intended for optimized artifacts used for releases

doc/man/cargo-bench.md

@@ -51,8 +51,8 @@ function to handle running benchmarks.
 
 By default, `cargo bench` uses the [`bench` profile], which enables
 optimizations and disables debugging information. If you need to debug a
-benchmark, you can use the `--profile=dev` command-line option to switch to
-the dev profile. You can then run the debug-enabled benchmark within a
+benchmark, you can use the `--profile=debug` command-line option to switch to
+the debug profile. You can then run the debug-enabled benchmark within a
 debugger.
 
 [`bench` profile]: ../reference/profiles.html#bench

doc/man/cargo-install.md

@@ -178,7 +178,7 @@ Directory to install packages into.
 {{> options-target-dir }}
 
 {{#option "`--debug`" }}
-Build with the `dev` profile instead of the `release` profile.
+Build with the `debug` profile instead of the `release` profile.
 See also the `--profile` option for choosing a specific profile by name.
 {{/option}}
 

doc/man/cargo-test.md

@@ -43,7 +43,10 @@ manifest settings, in which case your code will need to provide its own `main`
 function to handle running tests.
 
 By default, `cargo test` uses the [`test` profile], which enables
-debugging.
+some optimizations and disables debugging information for fast feedback. If you need to debug a
+test, you can use the `--profile=debug` command-line option to switch to
+the debug profile. You can then run the debug-enabled test within a
+debugger.
 
 [`test` profile]: ../reference/profiles.html#test
 

doc/man/generated_txt/cargo-bench.txt

@@ -46,9 +46,9 @@ DESCRIPTION
        By default, cargo bench uses the bench profile
        <https://doc.rust-lang.org/cargo/reference/profiles.html#bench>, which
        enables optimizations and disables debugging information. If you need to
-       debug a benchmark, you can use the --profile=dev command-line option to
-       switch to the dev profile. You can then run the debug-enabled benchmark
-       within a debugger.
+       debug a benchmark, you can use the --profile=debug command-line option
+       to switch to the debug profile. You can then run the debug-enabled
+       benchmark within a debugger.
 
    Working directory of benchmarks
        The working directory of every benchmark is set to the root directory of

doc/man/generated_txt/cargo-install.txt

@@ -226,8 +226,8 @@ OPTIONS
            workspace of the local crate unless --target-dir is specified.
 
        --debug
-           Build with the dev profile instead of the release profile. See also
-           the --profile option for choosing a specific profile by name.
+           Build with the debug profile instead of the release profile. See
+           also the --profile option for choosing a specific profile by name.
 
        --profile name
            Install with the given profile. See the reference