testcase for compose file read from stdin

Signed-off-by: Nicolas De Loof <nicolas.deloof@gmail.com>

tests/acceptance/cli_test.py

@@ -48,6 +48,7 @@ BUILD_PULL_TEXT = 'Status: Image is up to date for busybox:1.27.2'
 def start_process(base_dir, options):
     proc = subprocess.Popen(
         ['docker-compose'] + options,
+        stdin=subprocess.PIPE,
         stdout=subprocess.PIPE,
         stderr=subprocess.PIPE,
         cwd=base_dir)
@@ -55,8 +56,8 @@ def start_process(base_dir, options):
     return proc
 
 
-def wait_on_process(proc, returncode=0):
-    stdout, stderr = proc.communicate()
+def wait_on_process(proc, returncode=0, stdin=None):
+    stdout, stderr = proc.communicate(input=stdin)
     if proc.returncode != returncode:
         print("Stderr: {}".format(stderr))
         print("Stdout: {}".format(stdout))
@@ -64,10 +65,10 @@ def wait_on_process(proc, returncode=0):
     return ProcessResult(stdout.decode('utf-8'), stderr.decode('utf-8'))
 
 
-def dispatch(base_dir, options, project_options=None, returncode=0):
+def dispatch(base_dir, options, project_options=None, returncode=0, stdin=None):
     project_options = project_options or []
     proc = start_process(base_dir, project_options + options)
-    return wait_on_process(proc, returncode=returncode)
+    return wait_on_process(proc, returncode=returncode, stdin=stdin)
 
 
 def wait_on_condition(condition, delay=0.1, timeout=40):
@@ -156,8 +157,8 @@ class CLITestCase(DockerClientTestCase):
             self._project = get_project(self.base_dir, override_dir=self.override_dir)
         return self._project
 
-    def dispatch(self, options, project_options=None, returncode=0):
-        return dispatch(self.base_dir, options, project_options, returncode)
+    def dispatch(self, options, project_options=None, returncode=0, stdin=None):
+        return dispatch(self.base_dir, options, project_options, returncode, stdin)
 
     def execute(self, container, cmd):
         # Remove once Hijack and CloseNotifier sign a peace treaty
@@ -241,6 +242,17 @@ class CLITestCase(DockerClientTestCase):
         self.base_dir = 'tests/fixtures/v2-full'
         assert self.dispatch(['config', '--quiet']).stdout == ''
 
+    def test_config_stdin(self):
+        config = b"""version: "3.7"
+services:
+  web:
+    image: nginx
+  other:
+    image: alpine
+"""
+        result = self.dispatch(['-f', '-', 'config', '--services'], stdin=config)
+        assert set(result.stdout.rstrip().split('\n')) == {'web', 'other'}
+
     def test_config_with_hash_option(self):
         self.base_dir = 'tests/fixtures/v2-full'
         result = self.dispatch(['config', '--hash=*'])