rust_uprev: make find_ebuild_for_rust_version() call find_ebuild_path()

Previously, find_ebuild_for_rust_version() enumerated all versions of
dev-lang/rust, then filtered them to only those that match the specified
version. Instead, call find_ebuild_path(), which finds the requested
version directly and also contains an implementation of the logic
that tests only one version exists and properly accounts for symlinks.

BUG=b:318424456
TEST=presubmit, use the new code to create a rust uprev

Change-Id: Id7a058cb58a94cfa8a208d92ba6fc24b6344a683
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/5233111
Reviewed-by: George Burgess <gbiv@chromium.org>
Commit-Queue: Bob Haarman <inglorion@chromium.org>
Tested-by: Bob Haarman <inglorion@chromium.org>
Reviewed-by: Jordan Abrahams-Whitehead <ajordanr@google.com>

1 files changed, 2 insertions, 11 deletions

diff --git a/rust_tools/rust_uprev.py b/rust_tools/rust_uprev.py
index d3b445b9..9c0570c5 100755
--- a/rust_tools/rust_uprev.py
+++ b/rust_tools/rust_uprev.py
@@ -956,17 +956,8 @@ def find_oldest_rust_version() -> RustVersion:
 
 
 def find_ebuild_for_rust_version(version: RustVersion) -> Path:
-    rust_ebuilds = [
-        ebuild for x, ebuild in find_rust_versions() if x == version
-    ]
-    if not rust_ebuilds:
-        raise ValueError(f"No Rust ebuilds found matching {version}")
-    if len(rust_ebuilds) > 1:
-        raise ValueError(
-            f"Multiple Rust ebuilds found matching {version}: "
-            f"{rust_ebuilds}"
-        )
-    return rust_ebuilds[0]
+    """Returns the path of the ebuild for the given version of dev-lang/rust."""
+    return find_ebuild_path(RUST_PATH, "rust", version)
 
 
 def rebuild_packages(version: RustVersion):