London | 26-Mar-SDC | Craig D'Silva | Sprint 4 | Implement Shell Tools Python

implement-shell-tools/cat/cat.py

@@ -0,0 +1,39 @@
+import argparse
+
+parser = argparse.ArgumentParser(prog="cat", description="Prints the output of a file to the console")
+parser.add_argument("-n", "--number", help="Displays the lines along with their number", action="store_true")
+parser.add_argument("-b", "--nonblank", help="Displays the lines along with their number skipping the blank lines", action="store_true")
+parser.add_argument("path", help="The file path", nargs="+")
+
+args = parser.parse_args()
+
+show_lines = args.number
+non_blank = args.nonblank
+
+if show_lines == True and non_blank == True:
+    print("Error: Cannot use -n and -b together. Please use only one flag at a time.")
+    exit()
+
+text = ""
+i = 1
+
+for file in args.path:
+    f = open(file)
+    text += f.read()
+
+text_list = text.split("\n")
+text_list.pop(len(text_list) - 1)
+
+if (show_lines == False and non_blank == False):
+    print("\n".join(text_list))
+    exit()
+
+for line in text_list:
+    if non_blank == True and line != "":
+        print("     " + str(i) + " " + line)
+        i += 1
+    elif non_blank == False:
+        print("     " + str(i) + " " + line)
+        i += 1
+    else:
+        print("")

implement-shell-tools/ls/ls.py

@@ -0,0 +1,29 @@
+import argparse
+from os import listdir
+
+parser = argparse.ArgumentParser(prog="ls", description="List directory contents.  Ignore files and directories starting with a '.' by default")
+parser.add_argument("-1", dest="one", help="List one file per line.", action="store_true")
+parser.add_argument("-a", help="Do not ignore hidden files (files with names that start with '.').", action="store_true")
+parser.add_argument("path", help="The directory path (optional).", default=".", nargs="?")
+
+args = parser.parse_args()
+
+path = args.path
+
+show_hidden = args.a
+one_per_line = args.one
+
+contents = []
+
+for f in listdir(path):
+    if show_hidden == False and f[0] != ".":
+        contents.append(f)
+    if show_hidden == True:
+        contents.append(f)
+
+contents.sort()
+
+if one_per_line == True:
+    print("\n".join(contents))
+else:
+    print("  ".join(contents))

implement-shell-tools/wc/wc.py

@@ -0,0 +1,62 @@
+import argparse
+
+parser = argparse.ArgumentParser(prog="wc", description="Print  newline, word, and byte counts for each FILE, and a total line if more than one FILE is specified.")
+parser.add_argument("-w", "--words", help="print the word counts", action="store_true")
+parser.add_argument("-l", "--line", help="print the newline counts", action="store_true")
+parser.add_argument("-c", "--bytes", help="print the byte counts", action="store_true")
+parser.add_argument("path", help="The file path", nargs="+")
+
+args = parser.parse_args()
+
+lines = 0
+words = 0
+bytes = 0
+
+l = True
+w = True
+c = True
+
+if args.words == True or args.line == True or args.bytes == True:
+    l = args.line
+    w = args.words
+    c = args.bytes
+
+file_data = {}
+file_data_with_newline = {}
+
+for file in args.path:
+    f = open(file)
+    file_data[file] = f.read().split("\n")
+
+for file in args.path:
+    f = open(file)
+    file_data_with_newline[file] = f.read()
+
+def print_helper(line, word, byte, file_name):
+    text = [" "]
+    if l == True:
+        text.append(str(line))
+        text.append(" ")
+    if w == True:
+        text.append(str(word))
+        text.append(" ")
+    if c == True:
+        text.append(str(byte))
+        text.append(" ")
+    text.append(file_name)
+    print("".join(text))
+
+for f in file_data:
+    word_per_line = 0
+    byte_per_line = 0
+    for line in file_data[f]:
+        word_per_line += len(line.split())
+    for line in file_data_with_newline[f]:
+        byte_per_line += len(line.encode("utf-8"))
+    lines += len(file_data[f]) - 1
+    words += word_per_line
+    bytes += byte_per_line
+    print_helper(len(file_data[f]) - 1, word_per_line, byte_per_line, f)
+
+if len(args.path) > 1:
+    print_helper(lines, words, bytes, "total")