From 031314863c129efb5259c9cde405a96774697b4c Mon Sep 17 00:00:00 2001
From: James Osborne <jameso@graphcore.ai>
Date: Mon, 22 Jan 2024 13:49:54 +0000
Subject: [PATCH 1/2] Handle emptry list items

Add `select()` filter to the creation of `grub_cmdline_linux_new`
removes empty list elements, which for example might exist in
`kernal_cmdline` as a result of defaults.
---
 roles/grubcmdline/tasks/main.yml | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/roles/grubcmdline/tasks/main.yml b/roles/grubcmdline/tasks/main.yml
index f2f12d8..e8d29b1 100644
--- a/roles/grubcmdline/tasks/main.yml
+++ b/roles/grubcmdline/tasks/main.yml
@@ -1,4 +1,3 @@
----
 - name: Check current kernel command line args
   ansible.builtin.command: cat /proc/cmdline
   register: result
@@ -23,9 +22,7 @@
 - name: Set fact containing GRUB_CMDLINE_LINUX_DEFAULT
   ansible.builtin.set_fact:
     grub_cmdline_linux_default: >-
-      {{ grub_result.content | b64decode | regex_search('^GRUB_CMDLINE_LINUX_DEFAULT.*$', multiline=True)
-      | regex_replace('^GRUB_CMDLINE_LINUX_DEFAULT="(.*)"$', '\1') }}
-
+      {{ grub_result.content | b64decode | regex_search('^GRUB_CMDLINE_LINUX_DEFAULT.*$', multiline=True) | regex_replace('^GRUB_CMDLINE_LINUX_DEFAULT="(.*)"$', '\1') }} #magic___^_^___line
 - name: Display GRUB_CMDLINE_DEFAULT
   ansible.builtin.debug:
     var: grub_cmdline_linux_default
@@ -42,7 +39,7 @@
 
 - name: Updated kernel cmd line params
   ansible.builtin.set_fact:
-    grub_cmdline_linux_new: "{{ grub_cmdline_linux_default.split() | difference(grub_cmdline_linux_remove) + kernel_cmdline }}"
+    grub_cmdline_linux_new: "{{ grub_cmdline_linux_default.split() | difference(grub_cmdline_linux_remove) + kernel_cmdline | select() }}"
 
 - name: Display newly computed GRUB_CMDLINE_DEFAULT
   ansible.builtin.debug:

From 2cb415a7164f78134a61a7efab48570122949005 Mon Sep 17 00:00:00 2001
From: James Osborne <jameso@graphcore.ai>
Date: Tue, 23 Jan 2024 11:47:33 +0000
Subject: [PATCH 2/2] Changes requested on PR

---
 roles/grubcmdline/tasks/main.yml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/roles/grubcmdline/tasks/main.yml b/roles/grubcmdline/tasks/main.yml
index e8d29b1..46584d7 100644
--- a/roles/grubcmdline/tasks/main.yml
+++ b/roles/grubcmdline/tasks/main.yml
@@ -1,3 +1,4 @@
+---
 - name: Check current kernel command line args
   ansible.builtin.command: cat /proc/cmdline
   register: result
@@ -22,7 +23,7 @@
 - name: Set fact containing GRUB_CMDLINE_LINUX_DEFAULT
   ansible.builtin.set_fact:
     grub_cmdline_linux_default: >-
-      {{ grub_result.content | b64decode | regex_search('^GRUB_CMDLINE_LINUX_DEFAULT.*$', multiline=True) | regex_replace('^GRUB_CMDLINE_LINUX_DEFAULT="(.*)"$', '\1') }} #magic___^_^___line
+      {{ grub_result.content | b64decode | regex_search('^GRUB_CMDLINE_LINUX_DEFAULT.*$', multiline=True) | regex_replace('^GRUB_CMDLINE_LINUX_DEFAULT="(.*)"$', '\1') }}
 - name: Display GRUB_CMDLINE_DEFAULT
   ansible.builtin.debug:
     var: grub_cmdline_linux_default