cat.py command

Author: TarasMykytiuk

implement-shell-tools/cat/cat.py

@@ -0,0 +1,47 @@
+import sys
+import os
+
+
+def main():
+    args = sys.argv[1:]
+    flags = []
+    addresses = []
+    for item in args:
+        if item[0] == "-":
+            flags.append(item)
+        else:
+            addresses.append(item)
+
+    outputLines = []
+    for fileAddress in addresses:
+        try:
+            lines = readFileByLines(fileAddress)
+            for line in lines:
+                outputLines.append(line)
+        except Exception as e:
+            print(e)
+    printLines(outputLines, flags)
+
+
+def readFileByLines(fileAddress):
+    file = open(fileAddress, "r", encoding="utf-8")
+    content = file.read()
+    lines = content.split("\n")
+    if len(lines) != 0 and lines[-1] == "":
+        lines.pop()
+    return lines
+
+
+def printLines(outputLines, flags):
+    lineNumber = 1
+    for line in outputLines:
+        if ("-n" in flags and "-b" not in flags) or ("-b" in flags and line != ""):
+            output = "     " + str(lineNumber) + "  " + line
+            print(output)
+            lineNumber += 1
+        else:
+            print(line)
+
+
+if __name__ == "__main__":
+    main()