package-installs: allow when filter to be a list

Allow the "when:" statements to be a list of values, which are
effectively anded together to filter the package install.

Change-Id: Ia6f10741fa6be24b11d6991c8a6b6e07951ff68d

diskimage_builder/elements/package-installs/README.rst

@@ -93,6 +93,9 @@ packages), you can use something like::
   other_package:
     when: DIB_FEATURE_FLAG!=0
 
+You can also use a list of items in the ``when`` statement, which will
+be effectively combined with *and*.
+
 DEPRECATED: Adding a file under your elements pre-install.d, install.d, or
 post-install.d directories called package-installs-<element-name> will cause
 the list of packages in that file to be installed at the beginning of the

diskimage_builder/elements/package-installs/bin/package-installs-squash

@@ -61,7 +61,7 @@ def _valid_for_arch(pkg_name, arch, not_arch):
     return not _is_arch_in_list(not_arch)
 
 
-def _when(statement):
+def _when(statements):
     '''evaulate a when: statement
 
     Evaluate statements of the form
@@ -74,15 +74,21 @@ def _when(statement):
 
     '''
     # No statement means install
-    if statement is None:
+    if statements is None:
         return True
 
+    if not isinstance(statements, list):
+        statements = [statements]
+
+    result = []
+
+    for s in statements:
         # FOO =  BAR
         # var op val
         match = re.match(
-        r"(?P<var>[\w]+)(\s*)(?P<op>=|!=)(\s*)(?P<val>.*)", statement)
+            r"(?P<var>[\w]+)(\s*)(?P<op>=|!=)(\s*)(?P<val>.*)", s)
         if not match:
-        print("Malformed when line: <%s>" % statement)
+            print("Malformed when line: <%s>" % s)
             sys.exit(1)
         match = match.groupdict()
         var = match['var']
@@ -97,15 +103,19 @@ def _when(statement):
 
         if op == '=':
             if val == os.environ[var]:
-            return True
+                result.append(True)
+                continue
         elif op == '!=':
             if val != os.environ[var]:
-            return True
+                result.append(True)
+                continue
         else:
             print("Malformed when op: %s" % op)
             sys.exit(1)
 
-    return False
+        result.append(False)
+
+    return all(result)
 
 
 def collect_data(data, objs, element_name):

diskimage_builder/elements/package-installs/tests/test_package_squash.py

@@ -138,3 +138,39 @@ class TestPackageInstall(base.BaseTestCase):
 
         self.assertRaises(RuntimeError, installs_squash.collect_data,
                           self.final_dict, objs, 'test_element')
+
+    @mock.patch.object(os, 'environ',
+                       dict(
+                           DIB_A_FEATURE='1',
+                           DIB_B_FEATURE='1',
+                           DIB_C_FEATURE='1',
+                           **os.environ))
+    def test_skip_when_list(self):
+        '''Exercise the when flag with lists'''
+        objs = {
+            'not_skipped_package': {
+                'when': [
+                    'DIB_A_FEATURE=1',
+                    'DIB_B_FEATURE=1',
+                    'DIB_C_FEATURE=1'
+                ]
+            },
+            'skipped_package': {
+                'when': [
+                    'DIB_A_FEATURE=1',
+                    'DIB_B_FEATURE=0',
+                    'DIB_C_FEATURE=1',
+                ]
+            },
+        }
+
+        result = installs_squash.collect_data(
+            self.final_dict, objs, 'test_element')
+
+        expected = {
+            'install.d': {
+                'install': [('not_skipped_package', 'test_element')]
+            }
+        }
+
+        self.assertThat(result, IsMatchingInstallList(expected))

releasenotes/notes/package-installs-when-list-cfc00032271bae75.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    The ``package-installs`` element can now take a list value for the
+    ``when`` environment filter.