ZA | 25-SDC-July | Luke Manyamazi | Sprint 4 | Python Implement Shell Tools Exercises

implement-shell-tools/cat/cat.py

@@ -0,0 +1,38 @@
+import glob
+import argparse
+
+def cat(filepath, n=False, b=False, line_counter=None):
+    try:
+        with open(filepath) as f:
+            for line in f:
+                if b:
+                    if line.strip():
+                        print(f"{line_counter[0]:6}\t{line}", end='')
+                        line_counter[0] += 1
+                    else:
+                        print(line, end='')
+                elif n:
+                    print(f"{line_counter[0]:6}\t{line}", end='')
+                    line_counter[0] += 1
+                else:
+                    print(line, end='')
+    except FileNotFoundError:
+        print(f"cat: {filepath}: No such file or directory")
+
+def main():
+    parser = argparse.ArgumentParser(description = "Concatenate files and print on the standard output.")
+    parser.add_argument('-n', action='store_true', help='number all output lines')
+    parser.add_argument('-b', action='store_true', help='number non-empty output lines')
+    parser.add_argument('files', nargs='+', help='files to concatenate')
+    args = parser.parse_args()
+
+    files = []
+    for pattern in args.files:
+        files.extend(glob.glob(pattern) or [pattern])
+
+    line_counter = [1]
+    for file in sorted(files):
+        cat(file, args.n, args.b, line_counter)
+
+if __name__ == "__main__":
+    main()

implement-shell-tools/ls/ls.py

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+import os
+import argparse
+
+def ls(path='.', one_column=False, show_hidden=False):
+    try:
+        files = os.listdir(path)
+        if not show_hidden:
+            files = [f for f in files if not f.startswith('.')]
+        files.sort()
+
+        if one_column:
+            print(*files, sep='\n')
+        else:
+            print(*files)
+    except FileNotFoundError:
+        print(f"ls: cannot access '{path}': No such file or directory")
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('-1', dest='one_column', action='store_true', help='list one file per line')
+    parser.add_argument('-a', action='store_true', help='show hidden files')
+    parser.add_argument('path', nargs='?', default='.', help='directory to list')
+    args = parser.parse_args()
+
+    ls(args.path, args.one_column, args.a)
+
+if __name__ == "__main__":
+    main()

implement-shell-tools/wc/wc.py

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+import argparse
+
+def wc(path, count_lines, count_words, count_bytes):
+    try:
+        with open(path, 'r') as f:
+            content = f.read()
+        lines = content.splitlines()
+        words = content.split()
+        bytes_ = len(content.encode('utf-8'))
+
+        parts = []
+        if count_lines: parts.append(str(len(lines)))
+        if count_words: parts.append(str(len(words)))
+        if count_bytes: parts.append(str(bytes_))
+
+        if not parts:
+            parts = [str(len(lines)), str(len(words)), str(bytes_)]
+        print(' '.join(parts), path)
+
+    except FileNotFoundError:
+        print(f"wc: {path}: No such file or directory")
+    except IsADirectoryError:
+        print(f"wc: {path}: Is a directory")
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('-l', action='store_true', help='Count lines')
+    parser.add_argument('-w', action='store_true', help='Count words')
+    parser.add_argument('-c', action='store_true', help='Count bytes')
+    parser.add_argument('paths', nargs='+', help='Files to count')
+    args = parser.parse_args()
+
+    for path in args.paths:
+        wc(path, args.l, args.w, args.c)
+
+if __name__ == "__main__":
+    main()