LONDON | 26-SDC-JUly | Boshra Mahmoudi | Sprint 4 | Implement shell tools in python

implement-shell-tools/cat/cat.py

@@ -0,0 +1,33 @@
+import argparse
+
+
+parser = argparse.ArgumentParser(
+  prog="cat implemnet by Python"
+)
+
+parser.add_argument("-n", action="store_true")
+parser.add_argument("-b", action="store_true")
+parser.add_argument("files", nargs="+")
+
+args = parser.parse_args()
+
+line_number = 1
+
+for filename in args.files:
+  try:
+    with open(filename) as file:
+      for line in file:
+        line = line.rstrip("\n")
+
+        if args.b and line == "":
+          print()
+          continue
+
+        if args.n or args.b:
+          print(f"{line_number} {line}")
+          line_number += 1
+        else:
+          print(line)
+
+  except FileNotFoundError:
+    print(f"{filename}: No such file or directory")

implement-shell-tools/ls/ls.py

@@ -0,0 +1,36 @@
+import argparse
+import os
+
+parser = argparse.ArgumentParser(
+  prog="ls implemnet by Python"
+)
+
+parser.add_argument("-1", action="store_true", dest="one_per_line")
+parser.add_argument("-a", action="store_true", dest="show_all")
+parser.add_argument("paths", nargs="*")
+
+args = parser.parse_args()
+
+if not args.paths:
+  args.paths = ["."]
+
+for path in args.paths:
+  if os.path.isdir(path):
+    files = sorted(os.listdir(path))
+
+    if not args.show_all:
+      files = [file for file in files if not file.startswith(".")]
+
+    if args.one_per_line:
+      for file in files:
+        print(file)
+    else:
+      for file in files:
+        print(file, end="  ")
+      print()
+
+  elif os.path.isfile(path):
+    print(path)
+
+  else:
+    print(f"{path}: No such file or directory")

implement-shell-tools/wc/wc.py

@@ -0,0 +1,51 @@
+import argparse
+
+
+parser = argparse.ArgumentParser()
+
+parser.add_argument("-l", action="store_true")
+parser.add_argument("-w", action="store_true")
+parser.add_argument("-c", action="store_true")
+parser.add_argument("files", nargs="+")
+
+args = parser.parse_args()
+
+
+def add_count(output, value):
+  output.append(str(value))
+
+
+total_lines = 0
+total_words = 0
+total_bytes = 0
+
+for filename in args.files:
+
+  with open(filename, "rb") as file:
+    content = file.read()
+
+  lines = content.count(b"\n")
+  words = len(content.split())
+  bytes_count = len(content)
+
+  total_lines += lines
+  total_words += words
+  total_bytes += bytes_count
+
+  if not args.l and not args.w and not args.c:
+    print(f"{lines:8} {words:8} {bytes_count:8} {filename}")
+
+  else:
+    output = []
+
+    if args.l:
+      add_count(output, lines)
+
+    if args.w:
+      add_count(output, words)
+
+    if args.c:
+      add_count(output, bytes_count)
+
+    print(f"{' '.join(output):>8} {filename}")
+