Merge pull request #48 from scikit-build/support-env-file-update-from…

…-step

ci/driver: Support environment file `env.json` update from within step.

CHANGES.rst

@@ -8,6 +8,8 @@ details, see the commit logs at http://github.com/scikit-build/scikit-ci
 Next Release
 ============
 
+* Support environment file `env.json` update from within step.
+
 Scikit-ci 0.19.0
 ================
 

ci/driver.py

@@ -33,12 +33,19 @@ def __init__(self, driver, env_file="env.json"):
 
     def __enter__(self):
         self.driver.load_env(self.env_file)
+        self.env_file_modified_time = 0
+        if os.path.exists(self.env_file):
+            self.env_file_modified_time = os.path.getmtime(self.env_file)
         return self.driver
 
     def __exit__(self, exc_type, exc_value, traceback):
         if exc_type is None and exc_value is None and traceback is None:
-            self.driver.save_env(self.driver.env, self.env_file)
-
+            # Skip saving if env_file has been modified since context was entered
+            current_env_file_modified_time = 0
+            if os.path.exists(self.env_file):
+                current_env_file_modified_time = os.path.getmtime(self.env_file)
+            if current_env_file_modified_time == self.env_file_modified_time:
+                self.driver.save_env(self.driver.env, self.env_file)
         self.driver.unload_env()
 
 

tests/test_scikit_ci.py

@@ -9,6 +9,7 @@
 
 from ruamel.yaml.compat import ordereddict
 
+import ci
 from . import captured_lines, display_captured_text, push_dir, push_env
 from ci.constants import SERVICES, SERVICES_ENV_VAR, STEPS
 from ci.driver import Driver, dependent_steps, execute_step
@@ -1203,3 +1204,31 @@ def test_issue39_propagate_command_script_error(tmpdir):
                 SKCIStepExecutionError,
                 message=".*Return code: 2.+Command:.+$(import foo; print(foo())).*"):
             execute_step("test", with_dependencies=False)
+
+
+def test_env_file_update_from_step(tmpdir):
+    tmpdir.join('scikit-ci.yml').write(textwrap.dedent(
+        r"""
+        schema_version: "{version}"
+        test:
+          commands:
+            # The following command is expected to fail
+            - python: |
+                      import os
+                      os.environ['SCIKIT_CI_UPDATE_FROM_STEP'] = '1'
+                      import sys
+                      sys.path.insert(0, "{ci_path}")
+                      import ci
+                      ci.driver.Driver.save_env(os.environ)
+        """
+    ).format(version=SCHEMA_VERSION, ci_path=os.path.join(os.path.dirname(ci.__file__), "..")))
+
+    service = 'circle'
+
+    environment = dict(os.environ)
+    enable_service(service, environment)
+
+    with push_dir(str(tmpdir)), push_env(**environment):
+        execute_step("test")
+        env = Driver.read_env()
+        assert env['SCIKIT_CI_UPDATE_FROM_STEP'] == '1'