diff --git a/pii_check/pii_check_hook.py b/pii_check/pii_check_hook.py
index 8192f16..d9200fc 100644
--- a/pii_check/pii_check_hook.py
+++ b/pii_check/pii_check_hook.py
@@ -37,7 +37,7 @@ def get_payload(content, enabled_entity_list, blocked_list):
 def get_flagged_lines(files):
     flagged = []
     for file in files:
-        if os.path.exists(file):
+        if os.path.exists(file) and not os.path.isdir(file):
             with open(file, "r") as fp:
                 lines = fp.readlines()
                 start_flag = False
diff --git a/requirements-test.txt b/requirements-test.txt
new file mode 100644
index 0000000..191320e
--- /dev/null
+++ b/requirements-test.txt
@@ -0,0 +1,4 @@
+pytest==7.2.1
+pytest-check==2.1.2
+python-dotenv==0.19.0
+requests==2.28.1
\ No newline at end of file
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/test_data/dir_with_files/file_with_pii.txt b/tests/test_data/dir_with_files/file_with_pii.txt
new file mode 100644
index 0000000..c3fb7da
--- /dev/null
+++ b/tests/test_data/dir_with_files/file_with_pii.txt
@@ -0,0 +1 @@
+Credit card number: 1234 5678 9101 1123
\ No newline at end of file
diff --git a/tests/test_data/dir_with_files/file_with_pii_flag b/tests/test_data/dir_with_files/file_with_pii_flag
new file mode 100644
index 0000000..f436311
--- /dev/null
+++ b/tests/test_data/dir_with_files/file_with_pii_flag
@@ -0,0 +1,10 @@
+PII_CHECK:OFF
+Some content in between the flags. Ideally this content won't be checked for PII.
+Below is a dummy PII to check this
+Credit card number: 1234 5678 9101 1123
+CVV: 123
+PII_CHECK:ON
+
+Some content where the check will be performed.
+Credit card number: 1234 5678 9101 1123
+CVV: 123
\ No newline at end of file
diff --git a/tests/test_data/dir_with_files/file_without_pii.txt b/tests/test_data/dir_with_files/file_without_pii.txt
new file mode 100644
index 0000000..700578d
--- /dev/null
+++ b/tests/test_data/dir_with_files/file_without_pii.txt
@@ -0,0 +1 @@
+Here's some content.
\ No newline at end of file
diff --git a/tests/test_data/symlink_of_dir_with_files b/tests/test_data/symlink_of_dir_with_files
new file mode 120000
index 0000000..5d87a7d
--- /dev/null
+++ b/tests/test_data/symlink_of_dir_with_files
@@ -0,0 +1 @@
+./dir_with_files
\ No newline at end of file
diff --git a/tests/test_get_flagged_lines.py b/tests/test_get_flagged_lines.py
new file mode 100644
index 0000000..9455cd7
--- /dev/null
+++ b/tests/test_get_flagged_lines.py
@@ -0,0 +1,13 @@
+import pytest_check as check
+from pii_check.pii_check_hook import get_flagged_lines
+
+
+def test_get_flagged_lines():
+    files = [
+        "tests/test_data/dir_with_files/file_with_pii.txt", "tests/test_data/dir_with_files/file_without_pii.txt",
+        "tests/test_data/dir_with_files/file_with_pii_flag_on", "tests/test_data/dir_with_files/file_with_pii_flag_off",
+        "tests/test_data/dir_with_files/file_with_pii_flag", "tests/test_data/symlink_of_dir_with_files"
+    ]
+    res = get_flagged_lines(files)
+    check.equal(res, [(1, 6, 'tests/test_data/dir_with_files/file_with_pii_flag')])
+