From ec82eb613c393496c6609dbd74d863de662a7e65 Mon Sep 17 00:00:00 2001
From: David Thompson <davidethompson@me.com>
Date: Tue, 7 Mar 2023 14:28:06 -0500
Subject: [PATCH] Adjust reported package number in python instead of shell
 (#26)

Create a data structure that holds the command
to list all packages, as well as a number to adjust
the reported number of packages by.
Use this instead of piping through `tail` for RHEL-like distros,
since using pipes in the command doesn't seem to work.

Fixes #24

Signed-off-by: David Thompson <davthomp@redhat.com>
---
 src/modules/packages.py | 45 ++++++++++++++++++++++++-----------------
 1 file changed, 27 insertions(+), 18 deletions(-)

diff --git a/src/modules/packages.py b/src/modules/packages.py
index 734f014..2cc9552 100644
--- a/src/modules/packages.py
+++ b/src/modules/packages.py
@@ -1,28 +1,37 @@
 from subprocess import check_output
 
-commands = [
-    "pacman -Qq --color never",  # Arch Linux
-    "dpkg-query -f '.\n' -W",  # Debian, Ubuntu, Mint
-    "dnf list installed | tail -n +2",  # Fedora, RHEL
-    "rpm -qa",  # RHEL, Fedora Core, CentOS
-    "yum list installed | tail -n +2",  # RHEL, Fedora Core, CentOS
-    "xbps-query -l",  # Void Linux
-    "zypper search -i",  # openSUSE
-    "kiss l",  # KISS Linux
-    "equery list '*'",  # Gentoo
-    "qlist -I",  # Gentoo
-    "pkg info -a",  # BSDs
-    "pkg_info",  # BSDs
-    "apk info",  # Alpine
-    "nix-store -qR /run/current-system/sw",  # Nix
+class PackagesCommand:
+    def __init__(self, command: str, adjust_amt: int = 0):
+        """
+        Represents a command that retries a newline seperated list of all packages on the system.
+        :param command: the command to run
+        :param adjust_amt: the amount to add/remove to the number reported by the command
+        """
+        self.command = command
+        self.adjust_amt = adjust_amt
+
+packages_commands: list[PackagesCommand] = [
+    PackagesCommand("pacman -Qq --color never"),  # Arch Linux
+    PackagesCommand("dpkg-query -f '.\n' -W"),  # Debian, Ubuntu, Mint
+    PackagesCommand("dnf list installed -q", -1),  # Fedora, RHEL
+    PackagesCommand("yum list installed -q", -1),  # RHEL, Fedora Core, CentOS
+    PackagesCommand("rpm -qa"),  # RHEL, Fedora Core, CentOS
+    PackagesCommand("xbps-query -l"),  # Void Linux
+    PackagesCommand("zypper search -i"),  # openSUSE
+    PackagesCommand("kiss l"),  # KISS Linux
+    PackagesCommand("equery list '*'"),  # Gentoo
+    PackagesCommand("qlist -I"),  # Gentoo
+    PackagesCommand("pkg info -a"),  # BSDs
+    PackagesCommand("pkg_info"),  # BSDs
+    PackagesCommand("apk info"),  # Alpine
+    PackagesCommand("nix-store -qR /run/current-system/sw"),  # Nix
 ]
 
-
 def get_num_packages() -> (int, bool):
-    for command in commands:
+    for packages_command in packages_commands:
         try:
             # Get the length of the output of the command - the number of packages
-            return len(check_output(command.split(" ")).decode("utf-8").split("\n")) - 1
+            return len(check_output(packages_command.command.split(" ")).decode("utf-8").split("\n")) - 1 + packages_command.adjust_amt
 
         except FileNotFoundError:
             # If the command doesn't exist, skip it