kernel_blacklist - revamped the module (#3329)

* kernel_blacklist - revamped the module

* file default and setting "lines" when file does not exist

* added changelog fragment

* added change in arg_spec to the documentation block

* Update plugins/modules/system/kernel_blacklist.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update plugins/modules/system/kernel_blacklist.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update plugins/modules/system/kernel_blacklist.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* fixed: initialize self.pattern before self.var.is_blacklisted

* File writing recoded

* added try/finally for the file

* multiple changes:

- fixed case when last line of the existing file has no newline char
- added integration tests

* PR: integration test now using remote_tmp_dir

Co-authored-by: Felix Fontein <felix@fontein.de>

tests/integration/targets/kernel_blacklist/aliases

@@ -0,0 +1 @@
+shippable/posix/group1

tests/integration/targets/kernel_blacklist/files/blacklist

@@ -0,0 +1,3 @@
+blacklist aaaa
+blacklist bbbb
+blacklist cccc

tests/integration/targets/kernel_blacklist/meta/main.yml

@@ -0,0 +1,2 @@
+dependencies:
+  - setup_remote_tmp_dir

tests/integration/targets/kernel_blacklist/tasks/main.yml

@@ -0,0 +1,90 @@
+---
+- name: set destination filename
+  set_fact:
+    bl_file: '{{ remote_tmp_dir }}/blacklist-ansible.conf'
+
+- name: copy blacklist file
+  copy:
+    src: 'files/blacklist'
+    dest: '{{ bl_file }}'
+
+- name: Original stat
+  stat:
+    path: '{{ bl_file }}'
+  register: orig_stat
+
+- name: remove non-existing item from list
+  community.general.kernel_blacklist:
+    blacklist_file: '{{ bl_file }}'
+    state: absent
+    name: zzzz
+  register: bl_test_1
+
+- name: add existing item from list
+  community.general.kernel_blacklist:
+    blacklist_file: '{{ bl_file }}'
+    state: present
+    name: bbbb
+  register: bl_test_1a
+
+- name: stat_test_1
+  stat:
+    path: '{{ bl_file }}'
+  register: stat_test_1
+
+- name: assert file is unchanged
+  assert:
+    that:
+    - bl_test_1 is not changed
+    - bl_test_1a is not changed
+    - orig_stat.stat.size == stat_test_1.stat.size
+    - orig_stat.stat.checksum == stat_test_1.stat.checksum
+    - orig_stat.stat.mtime == stat_test_1.stat.mtime
+    - stat_test_1.stat.checksum == 'blacklist aaaa\nblacklist bbbb\nblacklist cccc'|checksum
+
+- name: add new item to list
+  community.general.kernel_blacklist:
+    blacklist_file: '{{ bl_file }}'
+    state: present
+    name: dddd
+  register: bl_test_2
+
+- name: slurp_test_2
+  slurp:
+    src: '{{ bl_file }}'
+  register: slurp_test_2
+
+- name: assert element is added
+  assert:
+    that:
+    - bl_test_2 is changed
+    - slurp_test_2.content|b64decode == content
+  vars:
+    content: |
+      blacklist aaaa
+      blacklist bbbb
+      blacklist cccc
+      blacklist dddd
+
+- name: remove item from list
+  community.general.kernel_blacklist:
+    blacklist_file: '{{ bl_file }}'
+    state: absent
+    name: bbbb
+  register: bl_test_3
+
+- name: slurp_test_3
+  slurp:
+    src: '{{ bl_file }}'
+  register: slurp_test_3
+
+- name: assert element is added
+  assert:
+    that:
+    - bl_test_3 is changed
+    - slurp_test_3.content|b64decode == content
+  vars:
+    content: |
+      blacklist aaaa
+      blacklist cccc
+      blacklist dddd