Add integration test to cover generated .repo files

This test prefetches RPM content and proceeds to generate the .repo file
by using the `inject-files` command.

Since the steps for this test differ from the usual, it was necessary to
customize the test boilerplate to call `inject-files` without actually
fully building the image, since only the contents of the generated .repo
file need to be checked.

Signed-off-by: Bruno Pimentel <bpimente@redhat.com>

tests/integration/test_data/rpm_test_repo_file/cachi2.repo

@@ -0,0 +1,10 @@
+[another-repoid]
+baseurl=file:///tmp/rpm_test_repo_file-output/deps/rpm/x86_64/another-repoid
+gpgcheck=1
+[cachi2-aaa000]
+baseurl=file:///tmp/rpm_test_repo_file-output/deps/rpm/x86_64/cachi2-aaa000
+gpgcheck=1
+name=Generated repository containing all packages unaffiliated with any official repository
+[releases]
+baseurl=file:///tmp/rpm_test_repo_file-output/deps/rpm/x86_64/releases
+gpgcheck=1

tests/integration/test_rpm.py

@@ -1,3 +1,5 @@
+import os
+import re
 from pathlib import Path
 from typing import List
 
@@ -105,6 +107,77 @@ def test_rpm_packages(
     )
 
 
+@pytest.mark.parametrize(
+    "test_params",
+    [
+        pytest.param(
+            utils.TestParameters(
+                repo="https://github.com/cachito-testing/cachi2-rpm",
+                ref="ce7fed744fc8fc2fd5d8981027e519ecd50b8805",
+                packages=({"path": ".", "type": "rpm"},),
+                flags=["--dev-package-managers"],
+                check_output=False,
+                check_deps_checksums=False,
+                check_vendor_checksums=False,
+                expected_exit_code=0,
+            ),
+            id="rpm_test_repo_file",
+        ),
+    ],
+)
+def test_repo_files(
+    test_params: utils.TestParameters,
+    cachi2_image: utils.ContainerImage,
+    tmp_path: Path,
+    test_data_dir: Path,
+    request: pytest.FixtureRequest,
+) -> None:
+    """Test if the contents of the generated .repo file are correct."""
+    test_case = request.node.callspec.id
+    output_folder = tmp_path.joinpath(f"{test_case}-output")
+
+    source_folder = utils.clone_repository(
+        test_params.repo, test_params.ref, f"{test_case}-source", tmp_path
+    )
+
+    utils.fetch_deps_and_check_output(
+        tmp_path, test_case, test_params, source_folder, test_data_dir, cachi2_image
+    )
+
+    # call inject-files to create the .repo file
+    cmd = [
+        "inject-files",
+        output_folder,
+        "--for-output-dir",
+        Path("/tmp", f"{test_case}-output"),
+    ]
+    (output, exit_code) = cachi2_image.run_cmd_on_image(cmd, tmp_path)
+    assert exit_code == 0, f"Injecting project files failed. output-cmd: {output}"
+
+    # load .repo file contents
+    def read_and_normalize_repofile(path: Path) -> str:
+        with open(path) as file:
+            # whenever an RPM lacks a repoid in the lockfile, Cachi2 will resort to a randomly
+            # generated internal repoid, which needs to be replaced by a constant string so it can
+            # be tested consistently.
+            return re.sub(r"cachi2-[a-f0-9]{6}", "cachi2-aaa000", file.read())
+
+    repo_file_content = read_and_normalize_repofile(
+        output_folder.joinpath("deps/rpm/x86_64/repos.d/cachi2.repo")
+    )
+
+    # update test data if needed
+    expected_repo_file_path = test_data_dir.joinpath(test_case, "cachi2.repo")
+
+    if os.getenv("CACHI2_GENERATE_TEST_DATA") == "true":
+        expected_repo_file_path.parent.mkdir(parents=True, exist_ok=True)
+        with open(expected_repo_file_path, "w") as file:
+            file.write(repo_file_content)
+
+    # check if .repo file content matches the expected test data
+    assert repo_file_content == read_and_normalize_repofile(expected_repo_file_path)
+
+
 @pytest.mark.parametrize(
     "test_params, check_cmd, expected_cmd_output",
     [