completed cat in python

Author: Alex-Jamshidi

implement-shell-tools/cat/cat.py

@@ -0,0 +1,65 @@
+import argparse
+import os
+from pathlib import Path
+
+# ===== Argument Handling =====
+parser = argparse.ArgumentParser(
+    prog="cat",
+    description="Prints file content",
+)
+
+parser.add_argument("-b", action="store_true", help="Numbers lines that aren't empty")
+parser.add_argument("-n", action="store_true", help="Numbers all lines")
+parser.add_argument("file_names", nargs="*", help="Files or folders to display")
+
+args = parser.parse_args()
+
+# ===== cat Procedure =====
+def cat(args):
+    cwd = os.getcwd()
+    all_files_contents = read_files(args.file_names, cwd)
+    execute_flags(all_files_contents)
+    print_lines(all_files_contents)
+
+# ===== Extracting Data from Arguments =====
+def read_files(file_names, cwd):
+    all_files_contents = []
+    
+    for file_name in file_names:
+        file_content = read_file(file_name, cwd)
+        all_files_contents.append(file_content.splitlines())
+    return all_files_contents
+
+def read_file(file_name, cwd):
+    file_path = Path(cwd) / file_name
+    with open(file_path, "r", encoding="utf-8") as f:
+        return f.read().rstrip()
+
+# ===== Flag Handling =====
+def execute_flags(all_files_contents):
+    if args.b:
+        line_number = 1
+        for file_content in all_files_contents:
+            for index, line in enumerate(file_content):
+                if line != "":
+                    file_content[index] = f"{line_number:>6}\t{line}"
+                    line_number += 1
+ 
+    elif args.n:
+        for file_idx, file_content in enumerate(all_files_contents):
+            all_files_contents[file_idx] = [
+                f"{line_idx:>6}\t{line}"
+                for line_idx, line in enumerate(file_content, start=1)
+            ]
+
+def make_list(output_string):
+    return output_string.replace("\t", "\n").replace("\n\n", "\n")
+
+# ===== Print Output =====
+def print_lines(all_files_contents):
+  for file_content in all_files_contents:
+    for line in file_content:
+      print(line)
+
+# ===== Run cat =====
+cat(parser.parse_args())