From 58983936927fbf1c99d655e31e81e569b218ed9c Mon Sep 17 00:00:00 2001
From: Yashna Parikh <yashnaparikh@microsoft.com>
Date: Mon, 22 Jun 2026 12:37:32 -0400
Subject: [PATCH 01/10] Address Pending Comments

---
 src/core/src/bootstrap/EnvLayer.py            |  4 +-
 .../package_managers/Dnf5PackageManager.py    |  4 +-
 src/core/tests/Test_EnvLayer.py               | 47 +++++++++++++++----
 3 files changed, 43 insertions(+), 12 deletions(-)

diff --git a/src/core/src/bootstrap/EnvLayer.py b/src/core/src/bootstrap/EnvLayer.py
index 4c01ea12..0c842b45 100644
--- a/src/core/src/bootstrap/EnvLayer.py
+++ b/src/core/src/bootstrap/EnvLayer.py
@@ -99,8 +99,8 @@ def get_package_manager(self):
 
         # Check for Azure Linux 4 or Above( uses dnf5)
         if self.is_distro_azure_linux_4(str(os_name)):
-            code, out = self.run_command_output('which dnf', False, False)
-            if code == 0:
+            code, out = self.run_command_output('dnf --version', False, False)
+            if code == 0 and out and str(out).strip().startswith('5'):
                 return Constants.DNF5
             else:
                 print("Error: Expected package manager dnf5 not found on this Azure Linux4 VM.")
diff --git a/src/core/src/package_managers/Dnf5PackageManager.py b/src/core/src/package_managers/Dnf5PackageManager.py
index d2942a1c..84d97d27 100644
--- a/src/core/src/package_managers/Dnf5PackageManager.py
+++ b/src/core/src/package_managers/Dnf5PackageManager.py
@@ -263,9 +263,9 @@ def get_dependent_list(self, packages):
         code, output = self.env_layer.run_command_output(cmd, False, False)
         self.composite_logger.log_verbose("[DNF5] Dependency simulation. [Command={0}][Code={1}]".format(cmd, str(code)))
         if code not in self.dnf5_simulation_valid_exit_codes:
-            self.composite_logger.log_error("[DNF5] Unexpected failure. [Command={0}][Code={1}][Output={2}]".format(cmd, str(code), output))
+            self.composite_logger.log_error("[DNF5] Unexpected failure during dependency simulation. [Command={0}][Code={1}][Output={2}]".format(cmd, str(code), output))
             error_msg = "DNF5 dependency simulation failed. Investigate and resolve unexpected return code({0}) from package manager on command: {1} ".format(str(code), cmd)
-            self.status_handler.add_error_to_status(error_msg, Constants.PatchOperationErrorCodes.DEFAULT_ERROR)
+            self.status_handler.add_error_to_status(error_msg, Constants.PatchOperationErrorCodes.PACKAGE_MANAGER_FAILURE)
             raise Exception(error_msg, "[{0}]".format(Constants.ERROR_ADDED_TO_STATUS))
 
         dependencies = self.extract_dependencies(output, packages)
diff --git a/src/core/tests/Test_EnvLayer.py b/src/core/tests/Test_EnvLayer.py
index cecc0ec8..69b36e87 100644
--- a/src/core/tests/Test_EnvLayer.py
+++ b/src/core/tests/Test_EnvLayer.py
@@ -45,6 +45,9 @@ def mock_platform_system_windows(self):
     def mock_linux_distribution(self):
         return ['test', 'test', 'test']
 
+    def mock_linux_distribution_to_return_azure_linux_4(self):
+        return ['Microsoft Azure Linux', '4.0', '']
+
     def mock_linux_distribution_to_return_azure_linux_3(self):
         return ['Microsoft Azure Linux', '3.0', '']
 
@@ -71,6 +74,14 @@ def mock_run_command_for_tdnf(self, cmd, no_output=False, chk_err=False):
             return 0, ''
         return -1, ''
 
+    def mock_run_command_for_dnf5(self, cmd, no_output=False, chk_err=False):
+        if cmd.find("dnf --version") > -1:
+            return 0, '5.2.0'
+        return -1, ''
+
+    def mock_distro_os_release_attr_return_azure_linux_4(self, attribute):
+        return '4.0.0'
+
     def mock_distro_os_release_attr_return_azure_linux_3(self, attribute):
         return '3.0.0'
 
@@ -96,18 +107,20 @@ def test_get_package_manager(self):
         self.backup_distro_os_release_attr = distro.os_release_attr
 
         test_input_output_table = [
-            [self.mock_run_command_for_apt, self.mock_linux_distribution, Constants.APT],
-            [self.mock_run_command_for_tdnf, self.mock_linux_distribution_to_return_azure_linux_3, Constants.TDNF],
-            [self.mock_run_command_for_yum, self.mock_linux_distribution_to_return_azure_linux_3, str()],  # check for Azure Linux machine which does not have tdnf
-            [self.mock_run_command_for_tdnf, self.mock_linux_distribution_to_return_azure_linux_2, Constants.TDNF],
-            [self.mock_run_command_for_yum, self.mock_linux_distribution, Constants.YUM],
-            [self.mock_run_command_for_zypper, self.mock_linux_distribution, Constants.ZYPPER],
-            [lambda cmd, no_output, chk_err: (-1, ''), self.mock_linux_distribution, str()],    # no matches for any package manager
+            [self.mock_run_command_for_apt, self.mock_linux_distribution, Constants.APT, self.mock_distro_os_release_attr_return_none],
+            [self.mock_run_command_for_dnf5, self.mock_linux_distribution_to_return_azure_linux_4, Constants.DNF5, self.mock_distro_os_release_attr_return_azure_linux_4],
+            [self.mock_run_command_for_tdnf, self.mock_linux_distribution_to_return_azure_linux_3, Constants.TDNF, self.mock_distro_os_release_attr_return_azure_linux_3],
+            [self.mock_run_command_for_yum, self.mock_linux_distribution_to_return_azure_linux_3, str(), self.mock_distro_os_release_attr_return_none],  # check for Azure Linux machine which does not have tdnf
+            [self.mock_run_command_for_tdnf, self.mock_linux_distribution_to_return_azure_linux_2, Constants.TDNF, self.mock_distro_os_release_attr_return_azure_linux_3],
+            [self.mock_run_command_for_yum, self.mock_linux_distribution, Constants.YUM, self.mock_distro_os_release_attr_return_none],
+            [self.mock_run_command_for_zypper, self.mock_linux_distribution, Constants.ZYPPER, self.mock_distro_os_release_attr_return_none],
+            [lambda cmd, no_output, chk_err: (-1, ''), self.mock_linux_distribution, str(), self.mock_distro_os_release_attr_return_none],    # no matches for any package manager
         ]
 
         for row in test_input_output_table:
             self.envlayer.run_command_output = row[0]
             self.envlayer.platform.linux_distribution = row[1]
+            distro.os_release_attr = row[3]
             package_manager = self.envlayer.get_package_manager()
             self.assertTrue(package_manager is row[2])
 
@@ -118,6 +131,7 @@ def test_get_package_manager(self):
         # restore original methods
         self.envlayer.run_command_output = self.backup_run_command_output
         self.envlayer.platform.linux_distribution = self.backup_linux_distribution
+        distro.os_release_attr = self.backup_distro_os_release_attr
         platform.system = self.backup_platform_system
 
     def test_is_distro_azure_linux_3(self):
@@ -138,6 +152,23 @@ def test_is_distro_azure_linux_3(self):
         # restore original methods
         distro.os_release_attr = self.backup_envlayer_distro_os_release_attr
 
+    def test_is_distro_azure_linux_4(self):
+        self.backup_envlayer_distro_os_release_attr = distro.os_release_attr
+
+        test_input_output_table = [
+            [self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, True],
+            [self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_none, False]
+        ]
+
+        for row in test_input_output_table:
+            distro_name = row[0]()[0]  # Extract distro name from tuple (first element)
+            distro.os_release_attr = row[1]
+            result = self.envlayer.is_distro_azure_linux_4(distro_name)
+            self.assertEqual(result, row[2])
+
+        # restore original methods
+        distro.os_release_attr = self.backup_envlayer_distro_os_release_attr
+
     def test_filesystem(self):
         # only validates if these invocable without exceptions
         backup_retry_count = Constants.MAX_FILE_OPERATION_RETRY_COUNT
@@ -152,7 +183,7 @@ def test_platform(self):
         self.envlayer.platform.cpu_arch()
         self.envlayer.platform.vm_name()
 
-    def test_get_package_manager_azure_linux_4_and_rhel10_not_supported(self):
+    def test_get_package_manager_rhel10_not_supported(self):
         """Test for RHEL 10 log unsupported message"""
         self.backup_platform_system = platform.system
         self.backup_linux_distribution = self.envlayer.platform.linux_distribution

From 735c1c969e8b957b30d449d9a80c38baa3f809db Mon Sep 17 00:00:00 2001
From: Yashna Parikh <yashnaparikh@microsoft.com>
Date: Mon, 22 Jun 2026 13:06:40 -0400
Subject: [PATCH 02/10] Address Copilot review

---
 src/core/tests/Test_EnvLayer.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/core/tests/Test_EnvLayer.py b/src/core/tests/Test_EnvLayer.py
index 69b36e87..9417d96a 100644
--- a/src/core/tests/Test_EnvLayer.py
+++ b/src/core/tests/Test_EnvLayer.py
@@ -111,7 +111,7 @@ def test_get_package_manager(self):
             [self.mock_run_command_for_dnf5, self.mock_linux_distribution_to_return_azure_linux_4, Constants.DNF5, self.mock_distro_os_release_attr_return_azure_linux_4],
             [self.mock_run_command_for_tdnf, self.mock_linux_distribution_to_return_azure_linux_3, Constants.TDNF, self.mock_distro_os_release_attr_return_azure_linux_3],
             [self.mock_run_command_for_yum, self.mock_linux_distribution_to_return_azure_linux_3, str(), self.mock_distro_os_release_attr_return_none],  # check for Azure Linux machine which does not have tdnf
-            [self.mock_run_command_for_tdnf, self.mock_linux_distribution_to_return_azure_linux_2, Constants.TDNF, self.mock_distro_os_release_attr_return_azure_linux_3],
+            [self.mock_run_command_for_tdnf, self.mock_linux_distribution_to_return_azure_linux_2, Constants.TDNF, self.mock_distro_os_release_attr_return_azure_linux_2],
             [self.mock_run_command_for_yum, self.mock_linux_distribution, Constants.YUM, self.mock_distro_os_release_attr_return_none],
             [self.mock_run_command_for_zypper, self.mock_linux_distribution, Constants.ZYPPER, self.mock_distro_os_release_attr_return_none],
             [lambda cmd, no_output, chk_err: (-1, ''), self.mock_linux_distribution, str(), self.mock_distro_os_release_attr_return_none],    # no matches for any package manager
@@ -122,7 +122,7 @@ def test_get_package_manager(self):
             self.envlayer.platform.linux_distribution = row[1]
             distro.os_release_attr = row[3]
             package_manager = self.envlayer.get_package_manager()
-            self.assertTrue(package_manager is row[2])
+            self.assertEqual(package_manager, row[2])
 
         # test for Windows
         platform.system = self.mock_platform_system_windows

From 8adaa58388606af9ec9952f9dbec3d45289ed6f6 Mon Sep 17 00:00:00 2001
From: Yashna Parikh <yashnaparikh@microsoft.com>
Date: Mon, 22 Jun 2026 15:15:41 -0400
Subject: [PATCH 03/10] Address Code Review comments #1

---
 src/core/src/bootstrap/EnvLayer.py | 14 +++++++++++---
 src/core/tests/Test_EnvLayer.py    | 20 ++++++++++++++++++--
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/src/core/src/bootstrap/EnvLayer.py b/src/core/src/bootstrap/EnvLayer.py
index 0c842b45..5699ceaa 100644
--- a/src/core/src/bootstrap/EnvLayer.py
+++ b/src/core/src/bootstrap/EnvLayer.py
@@ -99,11 +99,19 @@ def get_package_manager(self):
 
         # Check for Azure Linux 4 or Above( uses dnf5)
         if self.is_distro_azure_linux_4(str(os_name)):
+            code, out = self.run_command_output('which dnf', False, False)
+            if code != 0:
+                print("Error: Expected package manager dnf not found on this Azure Linux4 VM.")
+                return str()
+
             code, out = self.run_command_output('dnf --version', False, False)
-            if code == 0 and out and str(out).strip().startswith('5'):
-                return Constants.DNF5
+            if code == 0 and out:
+                #Output : dnf5 version 5.2.18.0
+                version = str(out).split()[-1]
+                if version.startswith('5'):
+                    return Constants.DNF5
             else:
-                print("Error: Expected package manager dnf5 not found on this Azure Linux4 VM.")
+                print("Error: Expected dnf version 5 not found on this Azure Linux4 VM.")
                 return str()
 
         # Check for Azure Linux (3 and below use TDNF)
diff --git a/src/core/tests/Test_EnvLayer.py b/src/core/tests/Test_EnvLayer.py
index 9417d96a..fd159c62 100644
--- a/src/core/tests/Test_EnvLayer.py
+++ b/src/core/tests/Test_EnvLayer.py
@@ -75,8 +75,10 @@ def mock_run_command_for_tdnf(self, cmd, no_output=False, chk_err=False):
         return -1, ''
 
     def mock_run_command_for_dnf5(self, cmd, no_output=False, chk_err=False):
-        if cmd.find("dnf --version") > -1:
-            return 0, '5.2.0'
+        if "which dnf" in cmd:
+            return 0, '/usr/bin/dnf'
+        if "dnf --version" in cmd:
+            return 0, 'dnf5 version 5.2.18.0'
         return -1, ''
 
     def mock_distro_os_release_attr_return_azure_linux_4(self, attribute):
@@ -208,6 +210,20 @@ def test_get_package_manager_rhel10_not_supported(self):
         # restore
         self.__restore_mocks()
 
+    def test_mock_command_fallback_paths(self):
+        """Test that mock commands return -1 for unexpected commands"""
+        # Cover line 60: apt mock with unexpected command
+        code, out = self.mock_run_command_for_apt('which yum')
+        self.assertEqual(code, -1)
+
+        # Cover line 75: dnf5 mock with unexpected command
+        code, out = self.mock_run_command_for_dnf5('which not-dnf')
+        self.assertEqual(code, -1)
+
+        # Cover line 75: dnf5 mock with unexpected command
+        code, out = self.mock_run_command_for_tdnf('which apt')
+        self.assertEqual(code, -1)
+
     def __restore_mocks(self):
         """Restore backed up mocks to their original state"""
         distro.os_release_attr = self.backup_distro_os_release_attr

From 1c9c1fffb859cf7156f7318a14b6497ad4b2c9dd Mon Sep 17 00:00:00 2001
From: Yashna Parikh <yashnaparikh@microsoft.com>
Date: Mon, 22 Jun 2026 16:07:00 -0400
Subject: [PATCH 04/10] Address Code Review comments #1

---
 src/core/src/bootstrap/EnvLayer.py |  5 ++-
 src/core/tests/Test_EnvLayer.py    | 49 ++++++++++++++++++++++++++----
 2 files changed, 45 insertions(+), 9 deletions(-)

diff --git a/src/core/src/bootstrap/EnvLayer.py b/src/core/src/bootstrap/EnvLayer.py
index 5699ceaa..7caa91fc 100644
--- a/src/core/src/bootstrap/EnvLayer.py
+++ b/src/core/src/bootstrap/EnvLayer.py
@@ -110,9 +110,8 @@ def get_package_manager(self):
                 version = str(out).split()[-1]
                 if version.startswith('5'):
                     return Constants.DNF5
-            else:
-                print("Error: Expected dnf version 5 not found on this Azure Linux4 VM.")
-                return str()
+            print("Error: Expected dnf version 5 not found on this Azure Linux4 VM.")
+            return str()
 
         # Check for Azure Linux (3 and below use TDNF)
         if self.is_distro_azure_linux(str(os_name)):
diff --git a/src/core/tests/Test_EnvLayer.py b/src/core/tests/Test_EnvLayer.py
index fd159c62..4b9620f6 100644
--- a/src/core/tests/Test_EnvLayer.py
+++ b/src/core/tests/Test_EnvLayer.py
@@ -81,6 +81,16 @@ def mock_run_command_for_dnf5(self, cmd, no_output=False, chk_err=False):
             return 0, 'dnf5 version 5.2.18.0'
         return -1, ''
 
+    def mock_run_command_for_dnf_not_found(self, cmd, no_output=False, chk_err=False):
+        return -1, ''
+
+    def mock_run_command_for_dnf_wrong_version(self, cmd, no_output=False, chk_err=False):
+        if "which dnf" in cmd:
+            return 0, '/usr/bin/dnf'
+        if "dnf --version" in cmd:
+            return 0, 'dnf version 4.14.0'
+        return -1, ''
+
     def mock_distro_os_release_attr_return_azure_linux_4(self, attribute):
         return '4.0.0'
 
@@ -159,7 +169,7 @@ def test_is_distro_azure_linux_4(self):
 
         test_input_output_table = [
             [self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, True],
-            [self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_none, False]
+            [self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_none, False],
         ]
 
         for row in test_input_output_table:
@@ -171,6 +181,33 @@ def test_is_distro_azure_linux_4(self):
         # restore original methods
         distro.os_release_attr = self.backup_envlayer_distro_os_release_attr
 
+    def test_get_package_manager_dnf5_error_cases(self):
+        """Test dnf5 error cases in get_package_manager"""
+        self.backup_platform_system = platform.system
+        self.backup_linux_distribution = self.envlayer.platform.linux_distribution
+        self.backup_run_command_output = self.envlayer.run_command_output
+        self.backup_distro_os_release_attr = distro.os_release_attr
+
+        platform.system = self.mock_platform_system
+        self.envlayer.platform.linux_distribution = self.mock_linux_distribution_to_return_azure_linux_4
+        distro.os_release_attr = self.mock_distro_os_release_attr_return_azure_linux_4
+
+        test_input_output_table = [
+            [self.mock_run_command_for_dnf_not_found, str()],
+            [self.mock_run_command_for_dnf_wrong_version, str()],
+        ]
+
+        for row in test_input_output_table:
+            self.envlayer.run_command_output = row[0]
+            result = self.envlayer.get_package_manager()
+            self.assertEqual(result, row[1])
+
+        # restore original methods
+        self.envlayer.run_command_output = self.backup_run_command_output
+        self.envlayer.platform.linux_distribution = self.backup_linux_distribution
+        distro.os_release_attr = self.backup_distro_os_release_attr
+        platform.system = self.backup_platform_system
+
     def test_filesystem(self):
         # only validates if these invocable without exceptions
         backup_retry_count = Constants.MAX_FILE_OPERATION_RETRY_COUNT
@@ -212,16 +249,16 @@ def test_get_package_manager_rhel10_not_supported(self):
 
     def test_mock_command_fallback_paths(self):
         """Test that mock commands return -1 for unexpected commands"""
-        # Cover line 60: apt mock with unexpected command
-        code, out = self.mock_run_command_for_apt('which yum')
+        code, out = self.mock_run_command_for_apt('which apt')
         self.assertEqual(code, -1)
 
-        # Cover line 75: dnf5 mock with unexpected command
         code, out = self.mock_run_command_for_dnf5('which not-dnf')
         self.assertEqual(code, -1)
 
-        # Cover line 75: dnf5 mock with unexpected command
-        code, out = self.mock_run_command_for_tdnf('which apt')
+        code, out = self.mock_run_command_for_dnf_wrong_version('dnf --v')
+        self.assertEqual(code, -1)
+
+        code, out = self.mock_run_command_for_tdnf('which not-tdnf')
         self.assertEqual(code, -1)
 
     def __restore_mocks(self):

From e8dd90b91d7622578c36f5119f3f238e9522f78e Mon Sep 17 00:00:00 2001
From: Yashna Parikh <yashnaparikh@microsoft.com>
Date: Tue, 23 Jun 2026 10:13:00 -0400
Subject: [PATCH 05/10] Address Code Review comment #2

---
 src/core/src/bootstrap/EnvLayer.py |  4 +++-
 src/core/tests/Test_EnvLayer.py    | 12 ++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/src/core/src/bootstrap/EnvLayer.py b/src/core/src/bootstrap/EnvLayer.py
index 7caa91fc..e0c5e77b 100644
--- a/src/core/src/bootstrap/EnvLayer.py
+++ b/src/core/src/bootstrap/EnvLayer.py
@@ -110,7 +110,9 @@ def get_package_manager(self):
                 version = str(out).split()[-1]
                 if version.startswith('5'):
                     return Constants.DNF5
-            print("Error: Expected dnf version 5 not found on this Azure Linux4 VM.")
+                print("Error: Expected dnf version 5 on this Azure Linux4 VM. Found: {0}".format(version))
+                return str()
+            print("Error: Unable to determine dnf version. Code={0}, Output={1}".format(code, out))
             return str()
 
         # Check for Azure Linux (3 and below use TDNF)
diff --git a/src/core/tests/Test_EnvLayer.py b/src/core/tests/Test_EnvLayer.py
index 4b9620f6..b130a95d 100644
--- a/src/core/tests/Test_EnvLayer.py
+++ b/src/core/tests/Test_EnvLayer.py
@@ -17,6 +17,7 @@
 import platform
 import sys
 import unittest
+
 # Conditional import for StringIO
 try:
     from StringIO import StringIO  # Python 2
@@ -91,6 +92,13 @@ def mock_run_command_for_dnf_wrong_version(self, cmd, no_output=False, chk_err=F
             return 0, 'dnf version 4.14.0'
         return -1, ''
 
+    def mock_run_command_for_dnf_version_command_failure(self, cmd, no_output=False, chk_err=False):
+        if "which dnf" in cmd:
+            return 0, '/usr/bin/dnf'
+        if "dnf --version" in cmd:
+            return -1, 'dnf version command failure'
+        return -1, ''
+
     def mock_distro_os_release_attr_return_azure_linux_4(self, attribute):
         return '4.0.0'
 
@@ -195,6 +203,7 @@ def test_get_package_manager_dnf5_error_cases(self):
         test_input_output_table = [
             [self.mock_run_command_for_dnf_not_found, str()],
             [self.mock_run_command_for_dnf_wrong_version, str()],
+            [self.mock_run_command_for_dnf_version_command_failure, str()]
         ]
 
         for row in test_input_output_table:
@@ -258,6 +267,9 @@ def test_mock_command_fallback_paths(self):
         code, out = self.mock_run_command_for_dnf_wrong_version('dnf --v')
         self.assertEqual(code, -1)
 
+        code, out = self.mock_run_command_for_dnf_version_command_failure('dnf --v')
+        self.assertEqual(code, -1)
+
         code, out = self.mock_run_command_for_tdnf('which not-tdnf')
         self.assertEqual(code, -1)
 

From 3f553637a2443a49057e5eaffebafd8f45dfbd5a Mon Sep 17 00:00:00 2001
From: Yashna Parikh <yashnaparikh@microsoft.com>
Date: Tue, 23 Jun 2026 10:37:10 -0400
Subject: [PATCH 06/10] Separate out methods

---
 src/core/src/bootstrap/EnvLayer.py | 21 +++++++++++++++------
 src/core/tests/Test_EnvLayer.py    |  1 -
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/core/src/bootstrap/EnvLayer.py b/src/core/src/bootstrap/EnvLayer.py
index e0c5e77b..e63f1994 100644
--- a/src/core/src/bootstrap/EnvLayer.py
+++ b/src/core/src/bootstrap/EnvLayer.py
@@ -81,6 +81,18 @@ def is_distro_rhel_10(self, distro_name):
         """ Checks if the current distro is RHEL 10 """
         return self.__is_matching_distro_and_version(distro_name, Constants.RED_HAT, version_to_match=10)
 
+    def __is_dnf_available(self):
+        code, _ = self.run_command_output('which dnf', False, False)
+        return code == 0
+
+    def __get_dnf_version(self):
+        code, out = self.run_command_output('dnf --version', False, False)
+        # Output : dnf5 version 5.2.18.0
+        if code != 0 or not out:
+            return code, out, None
+        version = str(out).split()[-1]
+        return code, out, version
+
     def get_package_manager(self):
         # type: () -> str
         """ Detects package manager type """
@@ -99,15 +111,12 @@ def get_package_manager(self):
 
         # Check for Azure Linux 4 or Above( uses dnf5)
         if self.is_distro_azure_linux_4(str(os_name)):
-            code, out = self.run_command_output('which dnf', False, False)
-            if code != 0:
+            if not self.__is_dnf_available():
                 print("Error: Expected package manager dnf not found on this Azure Linux4 VM.")
                 return str()
 
-            code, out = self.run_command_output('dnf --version', False, False)
-            if code == 0 and out:
-                #Output : dnf5 version 5.2.18.0
-                version = str(out).split()[-1]
+            code, out, version = self.__get_dnf_version()
+            if version:
                 if version.startswith('5'):
                     return Constants.DNF5
                 print("Error: Expected dnf version 5 on this Azure Linux4 VM. Found: {0}".format(version))
diff --git a/src/core/tests/Test_EnvLayer.py b/src/core/tests/Test_EnvLayer.py
index b130a95d..36140c95 100644
--- a/src/core/tests/Test_EnvLayer.py
+++ b/src/core/tests/Test_EnvLayer.py
@@ -17,7 +17,6 @@
 import platform
 import sys
 import unittest
-
 # Conditional import for StringIO
 try:
     from StringIO import StringIO  # Python 2

From 0ebb826942c514429b3fc4292d3fc7239195a21c Mon Sep 17 00:00:00 2001
From: Yashna Parikh <yashnaparikh@microsoft.com>
Date: Tue, 21 Jul 2026 12:16:27 -0400
Subject: [PATCH 07/10] Fix merge conflicts

---
 src/core/tests/Test_EnvLayer.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/core/tests/Test_EnvLayer.py b/src/core/tests/Test_EnvLayer.py
index 6523e8e0..7454af33 100644
--- a/src/core/tests/Test_EnvLayer.py
+++ b/src/core/tests/Test_EnvLayer.py
@@ -233,6 +233,7 @@ def test_get_package_manager_dnf5_error_cases(self):
             [self.mock_run_command_for_dnf_not_found, str()],
             [self.mock_run_command_for_dnf_wrong_version, str()],
             [self.mock_run_command_for_dnf_version_command_failure, str()]
+        ]
           
         for row in test_input_output_table:
             self.envlayer.run_command_output = row[0]

From 4b27687d08fb1773e832d8fc4f755fee2809226f Mon Sep 17 00:00:00 2001
From: Yashna Parikh <yashnaparikh@microsoft.com>
Date: Fri, 24 Jul 2026 11:53:29 -0400
Subject: [PATCH 08/10] Address code review

---
 src/core/src/bootstrap/EnvLayer.py            |  3 +-
 .../package_managers/Dnf5PackageManager.py    |  2 +
 src/core/tests/Test_EnvLayer.py               | 74 ++++++-------------
 3 files changed, 27 insertions(+), 52 deletions(-)

diff --git a/src/core/src/bootstrap/EnvLayer.py b/src/core/src/bootstrap/EnvLayer.py
index 39d18311..d908de8f 100644
--- a/src/core/src/bootstrap/EnvLayer.py
+++ b/src/core/src/bootstrap/EnvLayer.py
@@ -117,7 +117,8 @@ def get_package_manager(self):
 
             code, out, version = self.__get_dnf_version()
             if version:
-                if version.startswith('5'):
+                major_version = version.split('.')[0]
+                if major_version == '5':
                     return Constants.DNF5
                 print("Error: Expected dnf version 5 on this Azure Linux4 VM. Found: {0}".format(version))
                 return str()
diff --git a/src/core/src/package_managers/Dnf5PackageManager.py b/src/core/src/package_managers/Dnf5PackageManager.py
index 3310244c..2ced1186 100644
--- a/src/core/src/package_managers/Dnf5PackageManager.py
+++ b/src/core/src/package_managers/Dnf5PackageManager.py
@@ -727,3 +727,5 @@ def is_reboot_required_before_cert_update(self):
         """ Checks if a reboot is required before updating certificates """
         return False
     # endregion
+
+
diff --git a/src/core/tests/Test_EnvLayer.py b/src/core/tests/Test_EnvLayer.py
index 7454af33..5ec408fb 100644
--- a/src/core/tests/Test_EnvLayer.py
+++ b/src/core/tests/Test_EnvLayer.py
@@ -84,19 +84,16 @@ def mock_run_command_for_dnf5(self, cmd, no_output=False, chk_err=False):
     def mock_run_command_for_dnf_not_found(self, cmd, no_output=False, chk_err=False):
         return -1, ''
 
-    def mock_run_command_for_dnf_wrong_version(self, cmd, no_output=False, chk_err=False):
+    def mock_run_command_for_dnf_version_command(self, cmd, usecase="success"):
         if "which dnf" in cmd:
-            return 0, '/usr/bin/dnf'
+            return 0, "/usr/bin/dnf"
         if "dnf --version" in cmd:
-            return 0, 'dnf version 4.14.0'
-        return -1, ''
-
-    def mock_run_command_for_dnf_version_command_failure(self, cmd, no_output=False, chk_err=False):
-        if "which dnf" in cmd:
-            return 0, '/usr/bin/dnf'
-        if "dnf --version" in cmd:
-            return -1, 'dnf version command failure'
-        return -1, ''
+            if usecase == "wrong_version":
+                return 0, "dnf version 4.14.0"
+            if usecase == "version_command_failure":
+                return -1, "dnf version command failure"
+            return 0, "dnf version 5.2.6"
+        return -1, ""
 
     def mock_distro_os_release_attr_return_azure_linux_4(self, attribute):
         return '4.0.0'
@@ -156,22 +153,25 @@ def test_get_package_manager(self):
         self.backup_distro_os_release_attr = distro.os_release_attr
 
         test_input_output_table = [
-            [self.mock_run_command_for_apt, self.mock_linux_distribution, Constants.APT, self.mock_distro_os_release_attr_return_none],
-            [self.mock_run_command_for_dnf5, self.mock_linux_distribution_to_return_azure_linux_4, Constants.DNF5, self.mock_distro_os_release_attr_return_azure_linux_4],
-            [self.mock_run_command_for_tdnf, self.mock_linux_distribution_to_return_azure_linux_3, Constants.TDNF, self.mock_distro_os_release_attr_return_azure_linux_3],
-            [self.mock_run_command_for_yum, self.mock_linux_distribution_to_return_azure_linux_3, str(), self.mock_distro_os_release_attr_return_none],  # check for Azure Linux machine which does not have tdnf
-            [self.mock_run_command_for_tdnf, self.mock_linux_distribution_to_return_azure_linux_2, Constants.TDNF, self.mock_distro_os_release_attr_return_azure_linux_2],
-            [self.mock_run_command_for_yum, self.mock_linux_distribution, Constants.YUM, self.mock_distro_os_release_attr_return_none],
-            [self.mock_run_command_for_zypper, self.mock_linux_distribution, Constants.ZYPPER, self.mock_distro_os_release_attr_return_none],
-            [lambda cmd, no_output, chk_err: (-1, ''), self.mock_linux_distribution, str(), self.mock_distro_os_release_attr_return_none],    # no matches for any package manager
+            [self.mock_run_command_for_apt, self.mock_linux_distribution, self.mock_distro_os_release_attr_return_none, Constants.APT],
+            [self.mock_run_command_for_dnf5, self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, Constants.DNF5],
+            [self.mock_run_command_for_tdnf, self.mock_linux_distribution_to_return_azure_linux_3, self.mock_distro_os_release_attr_return_azure_linux_3, Constants.TDNF],
+            [self.mock_run_command_for_yum, self.mock_linux_distribution_to_return_azure_linux_3, self.mock_distro_os_release_attr_return_none, str()],  # check for Azure Linux machine which does not have tdnf
+            [self.mock_run_command_for_tdnf, self.mock_linux_distribution_to_return_azure_linux_2, self.mock_distro_os_release_attr_return_azure_linux_2, Constants.TDNF],
+            [self.mock_run_command_for_yum, self.mock_linux_distribution, self.mock_distro_os_release_attr_return_none, Constants.YUM],
+            [self.mock_run_command_for_zypper, self.mock_linux_distribution,  self.mock_distro_os_release_attr_return_none, Constants.ZYPPER],
+            [lambda cmd, no_output, chk_err: (-1, ''), self.mock_linux_distribution, self.mock_distro_os_release_attr_return_none, str()], # no matches for any package manager
+            [self.mock_run_command_for_dnf_not_found, self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()],
+            [lambda cmd, no_output, chk_err=False: self.mock_run_command_for_dnf_version_command(cmd, "wrong_version"), self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()],
+            [lambda cmd, no_output, chk_err=False: self.mock_run_command_for_dnf_version_command(cmd,"version_command_failure"), self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()]
         ]
 
         for row in test_input_output_table:
             self.envlayer.run_command_output = row[0]
             self.envlayer.platform.linux_distribution = row[1]
-            distro.os_release_attr = row[3]
+            distro.os_release_attr = row[2]
             package_manager = self.envlayer.get_package_manager()
-            self.assertEqual(package_manager, row[2])
+            self.assertEqual(package_manager, row[3])
 
         # test for Windows
         platform.system = self.mock_platform_system_windows
@@ -218,34 +218,6 @@ def test_is_distro_azure_linux_4(self):
         # restore original methods
         distro.os_release_attr = self.backup_envlayer_distro_os_release_attr
 
-    def test_get_package_manager_dnf5_error_cases(self):
-        """Test dnf5 error cases in get_package_manager"""
-        self.backup_platform_system = platform.system
-        self.backup_linux_distribution = self.envlayer.platform.linux_distribution
-        self.backup_run_command_output = self.envlayer.run_command_output
-        self.backup_distro_os_release_attr = distro.os_release_attr
-
-        platform.system = self.mock_platform_system
-        self.envlayer.platform.linux_distribution = self.mock_linux_distribution_to_return_azure_linux_4
-        distro.os_release_attr = self.mock_distro_os_release_attr_return_azure_linux_4
-
-        test_input_output_table = [
-            [self.mock_run_command_for_dnf_not_found, str()],
-            [self.mock_run_command_for_dnf_wrong_version, str()],
-            [self.mock_run_command_for_dnf_version_command_failure, str()]
-        ]
-          
-        for row in test_input_output_table:
-            self.envlayer.run_command_output = row[0]
-            result = self.envlayer.get_package_manager()
-            self.assertEqual(result, row[1])
-
-        # restore original methods
-        self.envlayer.run_command_output = self.backup_run_command_output
-        self.envlayer.platform.linux_distribution = self.backup_linux_distribution
-        distro.os_release_attr = self.backup_distro_os_release_attr
-        platform.system = self.backup_platform_system
-         
     def test_detect_confidential_vm_by_fde(self):
         backup_run_command_output = self.envlayer.run_command_output
         backup_read_with_retry = self.envlayer.file_system.read_with_retry
@@ -366,10 +338,10 @@ def test_mock_command_fallback_paths(self):
         code, out = self.mock_run_command_for_dnf5('which not-dnf')
         self.assertEqual(code, -1)
 
-        code, out = self.mock_run_command_for_dnf_wrong_version('dnf --v')
+        code, out = self.mock_run_command_for_dnf_version_command('dnf --v', "wrong_version")
         self.assertEqual(code, -1)
 
-        code, out = self.mock_run_command_for_dnf_version_command_failure('dnf --v')
+        code, out = self.mock_run_command_for_dnf_version_command('dnf --v', "version_command_failure")
         self.assertEqual(code, -1)
 
         code, out = self.mock_run_command_for_tdnf('which not-tdnf')

From d416f3750f0b0fc407d56352cbf31810bf274c6c Mon Sep 17 00:00:00 2001
From: Yashna Parikh <yashnaparikh@microsoft.com>
Date: Mon, 27 Jul 2026 10:36:55 -0400
Subject: [PATCH 09/10] Address code review

---
 src/core/src/bootstrap/EnvLayer.py | 20 ++++++++----------
 src/core/tests/Test_EnvLayer.py    | 33 +++++++++++++++++++++---------
 2 files changed, 31 insertions(+), 22 deletions(-)

diff --git a/src/core/src/bootstrap/EnvLayer.py b/src/core/src/bootstrap/EnvLayer.py
index d908de8f..3dc70e8e 100644
--- a/src/core/src/bootstrap/EnvLayer.py
+++ b/src/core/src/bootstrap/EnvLayer.py
@@ -90,7 +90,7 @@ def __get_dnf_version(self):
         # Output : dnf5 version 5.2.18.0
         if code != 0 or not out:
             return code, out, None
-        version = str(out).split()[-1]
+        version = str(out).split()[-1].split('.')[0]
         return code, out, version
 
     def get_package_manager(self):
@@ -111,19 +111,15 @@ def get_package_manager(self):
 
         # Check for Azure Linux 4 or Above( uses dnf5)
         if self.is_distro_azure_linux_4(str(os_name)):
-            if not self.__is_dnf_available():
-                print("Error: Expected package manager dnf not found on this Azure Linux4 VM.")
-                return str()
-
             code, out, version = self.__get_dnf_version()
-            if version:
-                major_version = version.split('.')[0]
-                if major_version == '5':
-                    return Constants.DNF5
-                print("Error: Expected dnf version 5 on this Azure Linux4 VM. Found: {0}".format(version))
+            if code == 0 and version == '5':
+                return Constants.DNF5
+            elif code == 0 and version != '5':
+                print("Error: Expected dnf version not found on this Azure Linux4 VM. [Expected={0}][Found={1}]".format("5", str(version)))
+                return str()
+            else:
+                print("Error: Expected package manager dnf5 not found on this Azure Linux4 VM")
                 return str()
-            print("Error: Unable to determine dnf version. Code={0}, Output={1}".format(code, out))
-            return str()
 
         # Check for Azure Linux (3 and below use TDNF)
         if self.is_distro_azure_linux(str(os_name)):
diff --git a/src/core/tests/Test_EnvLayer.py b/src/core/tests/Test_EnvLayer.py
index 5ec408fb..fd58fe6c 100644
--- a/src/core/tests/Test_EnvLayer.py
+++ b/src/core/tests/Test_EnvLayer.py
@@ -84,16 +84,29 @@ def mock_run_command_for_dnf5(self, cmd, no_output=False, chk_err=False):
     def mock_run_command_for_dnf_not_found(self, cmd, no_output=False, chk_err=False):
         return -1, ''
 
-    def mock_run_command_for_dnf_version_command(self, cmd, usecase="success"):
+    def mock_run_command_for_dnf_wrong_version(self, cmd, no_output=False, chk_err=False):
+        return self.mock_run_command_for_dnf_version_command(cmd, no_output, chk_err, "wrong_version")
+
+    def mock_run_command_for_dnf_version_command_failure(self, cmd, no_output=False, chk_err=False):
+        return self.mock_run_command_for_dnf_version_command(cmd, no_output, chk_err, "version_command_failure")
+
+    def mock_run_command_for_dnf_version_command(self, cmd, no_output=False, chk_err=False, usecase="success"):
+        code = -1
+        out = ""
         if "which dnf" in cmd:
-            return 0, "/usr/bin/dnf"
-        if "dnf --version" in cmd:
+            code = 0
+            out = "/usr/bin/dnf"
+        elif "dnf --version" in cmd:
             if usecase == "wrong_version":
-                return 0, "dnf version 4.14.0"
-            if usecase == "version_command_failure":
-                return -1, "dnf version command failure"
-            return 0, "dnf version 5.2.6"
-        return -1, ""
+                code = 0
+                out = "dnf version 4.14.0"
+            elif usecase == "version_command_failure":
+                code = -1
+                out = "dnf version command failure"
+            else:
+                code = 0
+                out = "dnf version 5.2.6"
+        return code, out
 
     def mock_distro_os_release_attr_return_azure_linux_4(self, attribute):
         return '4.0.0'
@@ -162,8 +175,8 @@ def test_get_package_manager(self):
             [self.mock_run_command_for_zypper, self.mock_linux_distribution,  self.mock_distro_os_release_attr_return_none, Constants.ZYPPER],
             [lambda cmd, no_output, chk_err: (-1, ''), self.mock_linux_distribution, self.mock_distro_os_release_attr_return_none, str()], # no matches for any package manager
             [self.mock_run_command_for_dnf_not_found, self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()],
-            [lambda cmd, no_output, chk_err=False: self.mock_run_command_for_dnf_version_command(cmd, "wrong_version"), self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()],
-            [lambda cmd, no_output, chk_err=False: self.mock_run_command_for_dnf_version_command(cmd,"version_command_failure"), self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()]
+            [self.mock_run_command_for_dnf_wrong_version, self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()],
+            [self.mock_run_command_for_dnf_version_command_failure, self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()]
         ]
 
         for row in test_input_output_table:

From f948f0536a67b8c165587c11f7a75dc5eac9520c Mon Sep 17 00:00:00 2001
From: Yashna Parikh <yashnaparikh@microsoft.com>
Date: Mon, 27 Jul 2026 10:43:19 -0400
Subject: [PATCH 10/10] Remove unused method

---
 src/core/src/bootstrap/EnvLayer.py |  4 ----
 src/core/tests/Test_EnvLayer.py    | 10 +++-------
 2 files changed, 3 insertions(+), 11 deletions(-)

diff --git a/src/core/src/bootstrap/EnvLayer.py b/src/core/src/bootstrap/EnvLayer.py
index 3dc70e8e..d2ebb25b 100644
--- a/src/core/src/bootstrap/EnvLayer.py
+++ b/src/core/src/bootstrap/EnvLayer.py
@@ -81,10 +81,6 @@ def is_distro_rhel_10(self, distro_name):
         """ Checks if the current distro is RHEL 10 """
         return self.__is_matching_distro_and_version(distro_name, Constants.RED_HAT, version_to_match=10)
 
-    def __is_dnf_available(self):
-        code, _ = self.run_command_output('which dnf', False, False)
-        return code == 0
-
     def __get_dnf_version(self):
         code, out = self.run_command_output('dnf --version', False, False)
         # Output : dnf5 version 5.2.18.0
diff --git a/src/core/tests/Test_EnvLayer.py b/src/core/tests/Test_EnvLayer.py
index fd58fe6c..2b51f9dd 100644
--- a/src/core/tests/Test_EnvLayer.py
+++ b/src/core/tests/Test_EnvLayer.py
@@ -75,8 +75,6 @@ def mock_run_command_for_tdnf(self, cmd, no_output=False, chk_err=False):
         return -1, ''
 
     def mock_run_command_for_dnf5(self, cmd, no_output=False, chk_err=False):
-        if "which dnf" in cmd:
-            return 0, '/usr/bin/dnf'
         if "dnf --version" in cmd:
             return 0, 'dnf5 version 5.2.18.0'
         return -1, ''
@@ -93,10 +91,7 @@ def mock_run_command_for_dnf_version_command_failure(self, cmd, no_output=False,
     def mock_run_command_for_dnf_version_command(self, cmd, no_output=False, chk_err=False, usecase="success"):
         code = -1
         out = ""
-        if "which dnf" in cmd:
-            code = 0
-            out = "/usr/bin/dnf"
-        elif "dnf --version" in cmd:
+        if "dnf --version" in cmd:
             if usecase == "wrong_version":
                 code = 0
                 out = "dnf version 4.14.0"
@@ -176,7 +171,8 @@ def test_get_package_manager(self):
             [lambda cmd, no_output, chk_err: (-1, ''), self.mock_linux_distribution, self.mock_distro_os_release_attr_return_none, str()], # no matches for any package manager
             [self.mock_run_command_for_dnf_not_found, self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()],
             [self.mock_run_command_for_dnf_wrong_version, self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()],
-            [self.mock_run_command_for_dnf_version_command_failure, self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()]
+            [self.mock_run_command_for_dnf_version_command_failure, self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, str()],
+            [self.mock_run_command_for_dnf_version_command, self.mock_linux_distribution_to_return_azure_linux_4, self.mock_distro_os_release_attr_return_azure_linux_4, Constants.DNF5],
         ]
 
         for row in test_input_output_table: