Add tests for `repo-space` command functionality

Introduce tests to verify the functionality of the `repo-space` command, including space reservation, freeing, display, and edge cases. These tests ensure proper handling of various scenarios and validation of the respective outputs.

src/borg/testsuite/archiver/repo_space_cmd_test.py

@@ -0,0 +1,80 @@
+from ...constants import *  # NOQA
+
+from . import cmd, generate_archiver_tests, RK_ENCRYPTION
+
+pytest_generate_tests = lambda metafunc: generate_archiver_tests(metafunc, kinds="local")  # NOQA
+
+
+def test_repo_space_basics(archivers, request):
+    archiver = request.getfixturevalue(archivers)
+    cmd(archiver, "repo-create", RK_ENCRYPTION)
+
+    # Initially, no space should be reserved.
+    output = cmd(archiver, "repo-space")
+    assert "There is 0 B reserved space in this repository." in output
+
+    # Test reserving some space.
+    output = cmd(archiver, "repo-space", "--reserve", "100M")
+    # The actual size will be rounded up to a multiple of 64MiB blocks.
+    # For 100MB, it should be 128MiB (2 blocks) == 134.22MB.
+    assert "There is 134.22 MB reserved space in this repository now." in output
+
+    # Check that space is reserved.
+    output = cmd(archiver, "repo-space")
+    assert "There is 134.22 MB reserved space in this repository." in output
+
+    # Test freeing the space.
+    output = cmd(archiver, "repo-space", "--free")
+    assert "Freed 134.22 MB in repository." in output
+
+    # Check that no space is reserved.
+    output = cmd(archiver, "repo-space")
+    assert "There is 0 B reserved space in this repository." in output
+
+
+def test_repo_space_modify_reservation(archivers, request):
+    archiver = request.getfixturevalue(archivers)
+    cmd(archiver, "repo-create", RK_ENCRYPTION)
+
+    # Reserve some space.
+    output = cmd(archiver, "repo-space", "--reserve", "50M")
+    assert "There is 67.11 MB reserved space in this repository now." in output
+
+    # Check that space is reserved.
+    output = cmd(archiver, "repo-space")
+    assert "There is 67.11 MB reserved space in this repository." in output
+
+    # Reserve more space.
+    output = cmd(archiver, "repo-space", "--reserve", "100M")
+    assert "There is 134.22 MB reserved space in this repository now." in output
+
+    # Check that space is reserved.
+    output = cmd(archiver, "repo-space")
+    assert "There is 134.22 MB reserved space in this repository." in output
+
+    # note: --reserve can only INCREASE the amount of reserved space.
+
+
+def test_repo_space_edge_cases(archivers, request):
+    archiver = request.getfixturevalue(archivers)
+    cmd(archiver, "repo-create", RK_ENCRYPTION)
+
+    # Test reserving 0 space (should not create any reservation).
+    output = cmd(archiver, "repo-space", "--reserve", "0")
+
+    # Check that no space is reserved.
+    output = cmd(archiver, "repo-space")
+    assert "There is 0 B reserved space in this repository." in output
+
+    # Test freeing when no space is reserved.
+    output = cmd(archiver, "repo-space", "--free")
+    assert "Freed 0 B in repository." in output
+
+    # Test reserving a very small amount of space (1KB).
+    # This should round up to at least one 64MiB block.
+    output = cmd(archiver, "repo-space", "--reserve", "1K")
+    assert "There is 67.11 MB reserved space in this repository now." in output
+
+    # Check that space is reserved (should be 64MiB).
+    output = cmd(archiver, "repo-space")
+    assert "There is 67.11 MB reserved space in this repository." in output