From 7150fbae5d3132f8d5b927123f6e267492d8378c Mon Sep 17 00:00:00 2001
From: Igor Motov <imotov@nvidia.com>
Date: Mon, 27 Jul 2026 12:30:47 -1000
Subject: [PATCH] Use a proper libcuvs library when RAPIDS_VERSION points to a
 PR branch (#181)

Many `cuvs-lucene` PRs depend on `cuvs` PRs that have not yet been merged. There is a way to test such `cuvs-lucene` PRs in CI by temporary pointing `RAPIDS_VERSION` to the `cuvs` PR branch. Unfortunately, this approach only works when the C portion of `cuvs` has not changed, because it relies on a conda's `libcuvs` rather than building it from source.

This PR works around this by downloading the pre-built libcuvs conda artifact from the cuVS PR's own CI run via gh run download. The artifact is extracted with rapids-extract-conda-files and prepended to LD_LIBRARY_PATH, so the Java bindings are built and tested against the correct library.

Authors:
  - Igor Motov (https://github.com/imotov)

Approvers:
  - Kyle Edwards (https://github.com/KyleFromNVIDIA)
  - Bradley Dice (https://github.com/bdice)
  - Corey J. Nolet (https://github.com/cjnolet)

URL: https://github.com/NVIDIA/cuvs-lucene/pull/181
---
 build.sh         | 23 ++++++++++++++++++++---
 ci/build_java.sh |  7 ++++++-
 2 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/build.sh b/build.sh
index 4ec8c087..39322568 100755
--- a/build.sh
+++ b/build.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-# SPDX-FileCopyrightText: Copyright (c) 2025-2026, NVIDIA CORPORATION.
+# SPDX-FileCopyrightText: Copyright (c) 2025-2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
 set -e -u -o pipefail
@@ -15,21 +15,38 @@ function hasArg {
     (( NUMARGS != 0 )) && (echo " ${ARGS} " | grep -q " $1 ")
 }
 
+
 if hasArg --build-cuvs-java; then
   CUVS_WORKDIR="cuvs-workdir"
   CUVS_GIT_REPO="https://github.com/rapidsai/cuvs.git"
+  BRANCH=$(cat "RAPIDS_BRANCH")
   if [[ -d "$CUVS_WORKDIR" && -n "$(ls -A "$CUVS_WORKDIR")" ]]; then
     echo "Directory '$CUVS_WORKDIR' exists and is not empty."
     pushd $CUVS_WORKDIR
     git pull
   else
-    BRANCH=$(cat "RAPIDS_BRANCH")
     echo "Directory '$CUVS_WORKDIR' does not exist or is empty. Cloning the cuvs's '$BRANCH' branch."
     # Correct branch selection is crucial to avoid version mismatch issues when testing.
     git clone --branch "$BRANCH" $CUVS_GIT_REPO $CUVS_WORKDIR
     pushd $CUVS_WORKDIR
   fi
-  ./build.sh java
+
+  # libcuvs comes from the conda packages, so normally only the java bindings have
+  # to be built. For a pull request, the conda packages do not contain the PR's
+  # changes, so CI downloads the pre-built libcuvs artifact from the PR's own CI run.
+  CUVS_BUILD_TARGETS=("java")
+  if hasArg --use-pr-libcuvs && [[ "$BRANCH" == pull-request/* ]]; then
+    PR_NUM="${BRANCH#pull-request/}"
+    echo "Downloading libcuvs conda artifact from cuvs PR #${PR_NUM}..."
+    LIBCUVS_CONDA_DIR=$(rapids-get-pr-artifact NVIDIA/cuvs "$PR_NUM" cpp conda)
+    LIBCUVS_DIR=$(rapids-extract-conda-files "$LIBCUVS_CONDA_DIR")
+    # The downloaded library has to take precedence over the one provided by the
+    # conda packages, both here and while running the java tests.
+    LD_LIBRARY_PATH="$LIBCUVS_DIR/lib${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}"
+    export LD_LIBRARY_PATH
+    echo "LD_LIBRARY_PATH is: $LD_LIBRARY_PATH"
+  fi
+  ./build.sh "${CUVS_BUILD_TARGETS[@]}"
   popd
 fi
 
diff --git a/ci/build_java.sh b/ci/build_java.sh
index 173ca55c..f9e3c1af 100755
--- a/ci/build_java.sh
+++ b/ci/build_java.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-# SPDX-FileCopyrightText: Copyright (c) 2025, NVIDIA CORPORATION.
+# SPDX-FileCopyrightText: Copyright (c) 2025-2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
 set -euo pipefail
@@ -16,6 +16,11 @@ fi
 # Always build cuvs-java when running the pipeline
 EXTRA_BUILD_ARGS+=("--build-cuvs-java")
 
+# When RAPIDS_BRANCH points at a cuvs pull request, the libcuvs from the conda
+# packages does not contain the PR's changes, so download the pre-built artifact
+# from the PR's CI run instead. Only done in CI, local builds use the conda packages.
+EXTRA_BUILD_ARGS+=("--use-pr-libcuvs")
+
 # shellcheck disable=SC1091
 . /opt/conda/etc/profile.d/conda.sh