don't require cmake/nvcc etc just for getting dlpack header

Author: benfred

.github/workflows/check-c-abi.yaml

@@ -36,38 +36,23 @@ jobs:
         with:
           python-version: '3.11'
 
-      - name: Install system dependencies
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y \
-            libclang-dev \
-            clang \
-            cmake \
-            ninja-build
-
       - name: Install Python dependencies
         run: |
           pip install --upgrade pip
           pip install -e ci/check_c_abi
 
-      - name: Build C++ project to get dependencies (dlpack)
+      - name: Get dlpack dependency
         run: |
-          mkdir -p cpp/build
-          cd cpp/build
-          cmake .. \
-            -GNinja \
-            -DCMAKE_BUILD_TYPE=Debug \
-            -DBUILD_TESTS=OFF \
-            -DBUILD_EXAMPLES=OFF
-          echo "Build directory created and dependencies fetched"
+          git clone https://github.com/dmlc/dlpack
 
       - name: Extract ABI from main branch
         run: |
           mkdir -p baseline
           check-c-abi extract \
             --header-path c/include \
             --include-file cuvs/core/all.h \
-            --output-file baseline/c_abi.json.gz
+            --output-file baseline/c_abi.json.gz \
+            --dlpack-include-path dlpack/include
           echo "ABI extracted from main branch (commit: ${{ github.sha }})"
 
       - name: Store commit-specific baseline
@@ -99,30 +84,14 @@ jobs:
         with:
           python-version: '3.11'
 
-      - name: Install system dependencies
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y \
-            libclang-dev \
-            clang \
-            cmake \
-            ninja-build
-
       - name: Install Python dependencies
         run: |
           pip install --upgrade pip
           pip install ci/check_c_abi
 
-      - name: Build C++ project to get dependencies (dlpack)
+      - name: Get dlpack dependency
         run: |
-          mkdir -p cpp/build
-          cd cpp/build
-          cmake .. \
-            -GNinja \
-            -DCMAKE_BUILD_TYPE=Debug \
-            -DBUILD_TESTS=OFF \
-            -DBUILD_EXAMPLES=OFF
-          echo "Build directory created and dependencies fetched"
+          git clone https://github.com/dmlc/dlpack
 
       - name: Find merge base commit
         id: merge-base
@@ -159,19 +128,13 @@ jobs:
           echo "⚠️ No baseline artifacts found, extracting from main branch..."
           echo "This is slower but ensures we always have a baseline for comparison."
           git worktree add ../cuvs-main main
-          mkdir -p ../cuvs-main/cpp/build
-          cd ../cuvs-main/cpp/build
-          cmake .. \
-            -GNinja \
-            -DCMAKE_BUILD_TYPE=Debug \
-            -DBUILD_TESTS=OFF \
-            -DBUILD_EXAMPLES=OFF
-          cd ../../..
           mkdir -p baseline
           check-c-abi extract \
             --header-path ../cuvs-main/c/include \
             --include-file cuvs/core/all.h \
-            --output-file baseline/c_abi.json.gz
+            --output-file baseline/c_abi.json.gz \
+            --dlpack-include-path dlpack/include
+
           echo "✓ Baseline ABI extracted from main branch"
 
       - name: Report baseline source
@@ -189,7 +152,8 @@ jobs:
           check-c-abi analyze \
             --abi-file baseline/c_abi.json.gz \
             --header-path c/include \
-            --include-file cuvs/core/all.h
+            --include-file cuvs/core/all.h \
+            --dlpack-include-path dlpack/include
 
       - name: Comment on PR with results
         if: failure() && github.event_name == 'pull_request'

ci/check_c_abi/check_c_abi/main.py

@@ -35,6 +35,23 @@ def main_cli():
             break
         current_path = current_path.parent
 
+    parent_parser = argparse.ArgumentParser(
+        add_help=False, description="Common arguments for all subcommands"
+    )
+    parent_parser.add_argument(
+        "--header-path",
+        help="Path of C headers to analyze (default: %(default)s)",
+        default=str(default_c_header_path),
+    )
+    parent_parser.add_argument(
+        "--include-file",
+        help="root header file to examine (default: %(default)s)",
+        default="cuvs/core/all.h",
+    )
+    parent_parser.add_argument(
+        "--dlpack-include-path", help="path of dlpack header include"
+    )
+
     parser = argparse.ArgumentParser(
         description="Analyze C headers for breaking ABI changes"
     )
@@ -43,44 +60,28 @@ def main_cli():
     )
 
     parser_extract = subparsers.add_parser(
-        "extract", help="Extract the ABI from a set of header files"
+        "extract",
+        parents=[parent_parser],
+        help="Extract the ABI from a set of header files",
     )
     parser_extract.add_argument(
         "--output-file",
         type=str,
         help="The file to output the ABI into (default: %(default)s)",
         default="c_abi.json.gz",
     )
-    parser_extract.add_argument(
-        "--header-path",
-        help="Path of C headers to extract the ABI from (default: %(default)s)",
-        default=str(default_c_header_path),
-    )
-    parser_extract.add_argument(
-        "--include-file",
-        help="root header file to examine (default: %(default)s)",
-        default="cuvs/core/all.h",
-    )
 
     parser_analyze = subparsers.add_parser(
-        "analyze", help="Analyze a set of header files for breaking changes"
+        "analyze",
+        parents=[parent_parser],
+        help="Analyze a set of header files for breaking changes",
     )
     parser_analyze.add_argument(
         "--abi-file",
         type=str,
         help="The extracted ABI file to compare against (default: %(default)s)",
         default="c_abi.json.gz",
     )
-    parser_analyze.add_argument(
-        "--header-path",
-        help="Path of C headers to analyze (default: %(default)s)",
-        default=str(default_c_header_path),
-    )
-    parser_analyze.add_argument(
-        "--include-file",
-        help="root header file to examine (default: %(default)s)",
-        default="cuvs/core/all.h",
-    )
 
     args = parser.parse_args()
     if not args.command:
@@ -89,23 +90,34 @@ def main_cli():
 
     header_path = pathlib.Path(args.header_path)
 
-    # TODO: better way of specifying the dlpack header source, since missing the dlpack.h
-    # header means that we all dlpack types get treated as 'int' which could be misleading
-    # when looking for differences in the ABI (like if we change a field from `DLDataType` to
-    # `int` without specifying the dlpack include directory, we won't know that the type has
-    # changed)
-    dlpack_header_path = (
-        header_path.parent.parent
-        / "cpp"
-        / "build"
-        / "_deps"
-        / "dlpack-src"
-        / "include"
-    )
-    if not dlpack_header_path.is_dir():
-        raise ValueError(f"dlpack header {dlpack_header_path} not found")
+    if args.dlpack_include_path:
+        dlpack_include_path = pathlib.Path(args.dlpack_include_path).resolve()
+
+    else:
+        # try getting from the cmake build directory dependencies if we
+        # haven't specified the include directory
+        dlpack_include_path = (
+            header_path.parent.parent
+            / "cpp"
+            / "build"
+            / "_deps"
+            / "dlpack-src"
+            / "include"
+        )
+
+    if not dlpack_include_path.is_dir():
+        raise ValueError(
+            f"dlpack header path '{dlpack_include_path}' not found"
+        )
+
+    if not (dlpack_include_path / "dlpack" / "dlpack.h").is_file():
+        raise ValueError(
+            f"dlpack header 'dlpack/dlpack.h' not found in '{dlpack_include_path}'"
+        )
+
+    print(f"using dlpack from {dlpack_include_path}")
 
-    extra_clang_args = [f"-I{str(dlpack_header_path)}"]
+    extra_clang_args = [f"-I{str(dlpack_include_path)}"]
 
     if args.command == "extract":
         abi = Abi.from_include_path(