impl PartialEq<{str,String}> for {Path,PathBuf}

[Kixunil]

This is a revival of #105877

Comparison of paths and strings is expected to be possible and needed e.g. in tests. This change adds the impls os PartialEq between strings and paths, both owned and unsized, in both directions.

ACP: rust-lang/libs-team#151

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[rust-log-analyzer]

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#18 exporting to docker image format
#18 sending tarball 21.1s done
#18 DONE 29.1s
##[endgroup]
Setting extra environment values for docker:  --env ENABLE_GCC_CODEGEN=1 --env GCC_EXEC_PREFIX=/usr/lib/gcc/
[CI_JOB_NAME=x86_64-gnu-llvm-19]
[CI_JOB_NAME=x86_64-gnu-llvm-19]
debug: `DISABLE_CI_RUSTC_IF_INCOMPATIBLE` configured.
---
sccache: Listening on address 127.0.0.1:4226
##[group]Configure the build
configure: processing command line
configure: 
configure: build.configure-args := ['--build=x86_64-unknown-linux-gnu', '--llvm-root=/usr/lib/llvm-19', '--enable-llvm-link-shared', '--set', 'rust.randomize-layout=true', '--set', 'rust.thin-lto-import-instr-limit=10', '--set', 'build.print-step-timings', '--enable-verbose-tests', '--set', 'build.metrics', '--enable-verbose-configure', '--enable-sccache', '--disable-manage-submodules', '--enable-locked-deps', '--enable-cargo-native-static', '--set', 'rust.codegen-units-std=1', '--set', 'dist.compression-profile=balanced', '--dist-compression-formats=xz', '--set', 'rust.lld=false', '--disable-dist-src', '--release-channel=nightly', '--enable-debug-assertions', '--enable-overflow-checks', '--enable-llvm-assertions', '--set', 'rust.verify-llvm-ir', '--set', 'rust.codegen-backends=llvm,cranelift,gcc', '--set', 'llvm.static-libstdcpp', '--set', 'gcc.download-ci-gcc=true', '--enable-new-symbol-mangling']
configure: build.build          := x86_64-unknown-linux-gnu
configure: target.x86_64-unknown-linux-gnu.llvm-config := /usr/lib/llvm-19/bin/llvm-config
configure: llvm.link-shared     := True
configure: rust.randomize-layout := True
configure: rust.thin-lto-import-instr-limit := 10
---

6    |                              |
7    |                              type must be known at this point
8    |
-    = note: cannot satisfy `String: PartialEq<_>`
-    = help: the following types implement trait `PartialEq<Rhs>`:
-              `String` implements `PartialEq<&str>`
-              `String` implements `PartialEq<ByteStr>`
-              `String` implements `PartialEq<ByteString>`
-              `String` implements `PartialEq<Cow<'_, str>>`
-       `String` implements `PartialEq<Path>`
-              `String` implements `PartialEq<PathBuf>`
-              `String` implements `PartialEq<str>`
-              `String` implements `PartialEq`
+    = note: multiple `impl`s satisfying `String: PartialEq<_>` found in the following crates: `alloc`, `std`:
+            - impl PartialEq for String;
+            - impl PartialEq<Path> for String;
+            - impl PartialEq<PathBuf> for String;
19 help: try using a fully qualified path to specify the expected types
20    |
21 LL -         if String::from("a") == "a".try_into().unwrap() {}


The actual stderr differed from the expected stderr.
To update references, rerun the tests and pass the `--bless` flag
To only update this specific test, also pass `--test-args inference/issue-72616.rs`

error: 1 errors occurred comparing output.
status: exit status: 1
command: env -u RUSTC_LOG_COLOR RUSTC_ICE="0" RUST_BACKTRACE="short" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/tests/ui/inference/issue-72616.rs" "-Zthreads=1" "-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX" "-Ztranslate-remapped-path-to-local-path=no" "-Z" "ignore-directory-in-diagnostics-source-blocks=/cargo" "-Z" "ignore-directory-in-diagnostics-source-blocks=/checkout/vendor" "--sysroot" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2" "--target=x86_64-unknown-linux-gnu" "--check-cfg" "cfg(test,FALSE)" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "-Zwrite-long-types-to-disk=no" "-Cstrip=debuginfo" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/inference/issue-72616" "-A" "unused" "-A" "internal_features" "-Crpath" "-Cdebuginfo=0" "-Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers"
stdout: none
--- stderr -------------------------------
error[E0283]: type annotations needed
##[error]  --> /checkout/tests/ui/inference/issue-72616.rs:22:37
   |
LL |         if String::from("a") == "a".try_into().unwrap() {}
   |                              --     ^^^^^^^^
   |                              |
   |                              type must be known at this point
   |
   = note: multiple `impl`s satisfying `String: PartialEq<_>` found in the following crates: `alloc`, `std`:
           - impl PartialEq for String;
           - impl PartialEq<Path> for String;
           - impl PartialEq<PathBuf> for String;
help: try using a fully qualified path to specify the expected types
   |
LL -         if String::from("a") == "a".try_into().unwrap() {}
LL +         if String::from("a") == <&str as TryInto<T>>::try_into("a").unwrap() {}
   |

error[E0283]: type annotations needed
##[error]  --> /checkout/tests/ui/inference/issue-72616.rs:22:37
   |
LL |         if String::from("a") == "a".try_into().unwrap() {}
   |                                     ^^^^^^^^
   |
   = note: multiple `impl`s satisfying `_: TryFrom<&str>` found in the following crates: `core`, `std`:
           - impl TryFrom<&str> for std::sys::net::connection::socket::LookupHost;
           - impl<T, U> TryFrom<U> for T
             where U: Into<T>;
   = note: required for `&str` to implement `TryInto<_>`
help: try using a fully qualified path to specify the expected types
   |
LL -         if String::from("a") == "a".try_into().unwrap() {}
LL +         if String::from("a") == <&str as TryInto<T>>::try_into("a").unwrap() {}
   |

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0283`.