Hermes-agent

tests/tools/test_docker_find.py

@@ -0,0 +1,104 @@
+"""Tests for tools.environments.docker.find_docker — Docker CLI discovery."""
+
+import os
+from unittest.mock import patch
+
+import pytest
+
+from tools.environments import docker as docker_mod
+
+
+@pytest.fixture(autouse=True)
+def _reset_cache():
+    """Clear the module-level docker executable cache between tests."""
+    docker_mod._docker_executable = None
+    yield
+    docker_mod._docker_executable = None
+
+
+class TestFindDocker:
+    def test_found_via_shutil_which(self):
+        with patch("tools.environments.docker.shutil.which", return_value="/usr/bin/docker"):
+            result = docker_mod.find_docker()
+        assert result == "/usr/bin/docker"
+
+    def test_not_in_path_falls_back_to_known_locations(self, tmp_path):
+        # Create a fake docker binary at a known path
+        fake_docker = tmp_path / "docker"
+        fake_docker.write_text("#!/bin/sh\n")
+        fake_docker.chmod(0o755)
+
+        with patch("tools.environments.docker.shutil.which", return_value=None), \
+             patch("tools.environments.docker._DOCKER_SEARCH_PATHS", [str(fake_docker)]):
+            result = docker_mod.find_docker()
+        assert result == str(fake_docker)
+
+    def test_returns_none_when_not_found(self):
+        with patch("tools.environments.docker.shutil.which", return_value=None), \
+             patch("tools.environments.docker._DOCKER_SEARCH_PATHS", ["/nonexistent/docker"]):
+            result = docker_mod.find_docker()
+        assert result is None
+
+    def test_caches_result(self):
+        with patch("tools.environments.docker.shutil.which", return_value="/usr/local/bin/docker"):
+            first = docker_mod.find_docker()
+        # Second call should use cache, not call shutil.which again
+        with patch("tools.environments.docker.shutil.which", return_value=None):
+            second = docker_mod.find_docker()
+        assert first == second == "/usr/local/bin/docker"
+
+    def test_env_var_override_takes_precedence(self, tmp_path):
+        """HERMES_DOCKER_BINARY overrides PATH and known-location discovery."""
+        fake_binary = tmp_path / "podman"
+        fake_binary.write_text("#!/bin/sh\n")
+        fake_binary.chmod(0o755)
+
+        with patch.dict(os.environ, {"HERMES_DOCKER_BINARY": str(fake_binary)}), \
+             patch("tools.environments.docker.shutil.which", return_value="/usr/bin/docker"):
+            result = docker_mod.find_docker()
+        assert result == str(fake_binary)
+
+    def test_env_var_override_ignored_if_not_executable(self, tmp_path):
+        """Non-executable HERMES_DOCKER_BINARY falls through to normal discovery."""
+        fake_binary = tmp_path / "podman"
+        fake_binary.write_text("#!/bin/sh\n")
+        fake_binary.chmod(0o644)  # not executable
+
+        with patch.dict(os.environ, {"HERMES_DOCKER_BINARY": str(fake_binary)}), \
+             patch("tools.environments.docker.shutil.which", return_value="/usr/bin/docker"):
+            result = docker_mod.find_docker()
+        assert result == "/usr/bin/docker"
+
+    def test_env_var_override_ignored_if_nonexistent(self):
+        """Non-existent HERMES_DOCKER_BINARY path falls through."""
+        with patch.dict(os.environ, {"HERMES_DOCKER_BINARY": "/nonexistent/podman"}), \
+             patch("tools.environments.docker.shutil.which", return_value="/usr/bin/docker"):
+            result = docker_mod.find_docker()
+        assert result == "/usr/bin/docker"
+
+    def test_podman_on_path_used_when_docker_missing(self):
+        """When docker is not on PATH, podman is tried next."""
+        def which_side_effect(name):
+            if name == "docker":
+                return None
+            if name == "podman":
+                return "/usr/bin/podman"
+            return None
+
+        with patch("tools.environments.docker.shutil.which", side_effect=which_side_effect), \
+             patch("tools.environments.docker._DOCKER_SEARCH_PATHS", []):
+            result = docker_mod.find_docker()
+        assert result == "/usr/bin/podman"
+
+    def test_docker_preferred_over_podman(self):
+        """When both docker and podman are on PATH, docker wins."""
+        def which_side_effect(name):
+            if name == "docker":
+                return "/usr/bin/docker"
+            if name == "podman":
+                return "/usr/bin/podman"
+            return None
+
+        with patch("tools.environments.docker.shutil.which", side_effect=which_side_effect):
+            result = docker_mod.find_docker()
+        assert result == "/usr/bin/docker"