user: fix default non-system user's shell on macOS

lib/ansible/modules/system/user.py

@@ -76,6 +76,9 @@ options:
         required: false
         description:
             - Optionally set the user's shell.
+            - On Mac OS X, before version 2.5, the default shell for non-system users was
+              /usr/bin/false. Since 2.5, the default shell for non-system users on
+              Mac OS X is /bin/bash.
     home:
         required: false
         description:
@@ -1763,6 +1766,11 @@ class DarwinUser(User):
                     os.makedirs(self.home)
                 self.chown_homedir(int(self.uid), int(self.group), self.home)
 
+        # dscl sets shell to /usr/bin/false when UserShell is not specified
+        # so set the shell to /bin/bash when the user is not a system user
+        if not self.system and self.shell is None:
+            self.shell = '/bin/bash'
+
         for field in self.fields:
             if field[0] in self.__dict__ and self.__dict__[field[0]]:
 

test/integration/targets/become/tasks/su.yml

@@ -4,18 +4,6 @@
   become_method: su
   user:
     name: "{{ become_test_user }}"
-  when: ansible_distribution != "MacOSX"
-
-
-- name: Create test user (become_method=su)
-  become: True
-  become_user: root
-  become_method: su
-  user:
-    name: "{{ become_test_user }}"
-    # explicitly set user shell since the default shell on OS X is /usr/bin/false
-    shell: /bin/bash
-  when: ansible_distribution == "MacOSX"
 
 - name: test becoming user (become_method=su)
   shell: whoami

test/integration/targets/user/tasks/main.yml

@@ -108,3 +108,53 @@
   assert:
       that:
           - '"ansibulluser" not in user_names2.stdout_lines'
+
+
+- block:
+    - name: create non-system user on OSX to test the shell is set to /bin/bash
+      user:
+        name: osxuser
+      register: osxuser_output
+
+    - name: validate the shell is set to /bin/bash
+      assert:
+        that:
+          - 'osxuser_output.shell == "/bin/bash"'
+
+    - name: cleanup
+      user:
+        name: osxuser
+        state: absent
+
+    - name: create system user on OSX to test the shell is set to /usr/bin/false
+      user:
+        name: osxuser
+        system: yes
+      register: osxuser_output
+
+    - name: validate the shell is set to /usr/bin/false
+      assert:
+        that:
+          - 'osxuser_output.shell == "/usr/bin/false"'
+
+    - name: cleanup
+      user:
+        name: osxuser
+        state: absent
+
+    - name: create non-system user on OSX and set the shell to /bin/sh
+      user:
+        name: osxuser
+        shell: /bin/sh
+      register: osxuser_output
+
+    - name: validate the shell is set to /bin/sh
+      assert:
+        that:
+          - 'osxuser_output.shell == "/bin/sh"'
+
+    - name: cleanup
+      user:
+        name: osxuser
+        state: absent
+  when: ansible_distribution == "MacOSX"