"""Tests for unstack dependency detection.
Tests that unstack correctly detects when commits have dependencies
(e.g., commit C modifies lines added by commit B).
Scenario:
- Commit A (HEAD~2): empty file
- Commit B (HEAD~1): adds 3 lines
- Commit C (HEAD): deletes line 2
Expected behavior:
- A -> B: SUCCESS (adds lines to empty file)
- A -> C: CONFLICT (C depends on B, tries to delete non-existent line)
- A -> B -> C: SUCCESS (C applies after B)
"""
import sys
sys.path.insert(0, '/app')
import subprocess
import pytest
def get_commit_sha(ref: str) -> str:
"""Helper to get commit SHA."""
result = subprocess.run(
["git", "rev-parse", ref],
cwd="/repo",
capture_output=True,
text=True,
check=True
)
return result.stdout.strip()
@pytest.mark.conflict
def test_independent_commit_succeeds():
"""Test that commit B (adds lines) can be applied independently."""
from git_polite import do_unstack
commit_a = get_commit_sha("HEAD~2") # Empty file
commit_b = get_commit_sha("HEAD~1") # Add 3 lines
# A -> B should succeed
result = do_unstack(
branches={
"feat/add-lines": [commit_b]
},
parent=commit_a
)
# Verify success
assert result["stats"]["successful_branches"] == 1, \
f"Expected 1 successful branch, got {result['stats']['successful_branches']}. Errors: {result['errors']}"
assert result["stats"]["failed_branches"] == 0
assert len(result["created_branches"]) == 1
# Verify the branch exists
branch_check = subprocess.run(
["git", "branch", "--list", "feat/add-lines"],
cwd="/repo",
capture_output=True,
text=True
)
assert "feat/add-lines" in branch_check.stdout
@pytest.mark.conflict
def test_dependent_commit_fails():
"""Test that commit C (deletes line 2) fails when applied without B."""
from git_polite import do_unstack
commit_a = get_commit_sha("HEAD~2") # Empty file
commit_c = get_commit_sha("HEAD") # Delete line 2
# A -> C should FAIL (C depends on B)
result = do_unstack(
branches={
"feat/delete-line": [commit_c]
},
parent=commit_a
)
# Verify that conflict was detected
assert result["stats"]["successful_branches"] == 0, \
f"Expected 0 successful branches, got {result['stats']['successful_branches']}"
assert result["stats"]["failed_branches"] == 1, \
f"Expected 1 failed branch, got {result['stats']['failed_branches']}"
# Check error details
assert len(result["errors"]) == 1
error = result["errors"][0]
assert error["branch"] == "feat/delete-line"
assert "conflict" in error["error"].lower(), \
f"Error message should mention conflict: {error['error']}"
# Verify the branch was not created
branch_check = subprocess.run(
["git", "branch", "--list", "feat/delete-line"],
cwd="/repo",
capture_output=True,
text=True
)
assert "feat/delete-line" not in branch_check.stdout, \
"Branch should not be created when conflict is detected"
@pytest.mark.conflict
def test_sequential_commits_succeed():
"""Test that B -> C succeeds when applied in order."""
from git_polite import do_unstack
commit_a = get_commit_sha("HEAD~2") # Empty file
commit_b = get_commit_sha("HEAD~1") # Add 3 lines
commit_c = get_commit_sha("HEAD") # Delete line 2
# A -> B -> C should succeed
result = do_unstack(
branches={
"feat/both": [commit_b, commit_c]
},
parent=commit_a
)
# Verify success
assert result["stats"]["successful_branches"] == 1, \
f"Expected 1 successful branch, got {result['stats']['successful_branches']}. Errors: {result['errors']}"
assert result["stats"]["failed_branches"] == 0
assert len(result["created_branches"]) == 1
branch = result["created_branches"][0]
assert branch["name"] == "feat/both"
assert len(branch["commits_applied"]) == 2, \
f"Expected 2 commits applied, got {len(branch['commits_applied'])}"
# Verify the branch exists
branch_check = subprocess.run(
["git", "branch", "--list", "feat/both"],
cwd="/repo",
capture_output=True,
text=True
)
assert "feat/both" in branch_check.stdout
