Extend output.print_msg() to accept 'error' and 'warning' values of 'to_print' argument

osc/output/output.py

@@ -1,7 +1,20 @@
 import sys
+from typing import Optional
+
+from . import tty
 
 
-def print_msg(*args, print_to="debug"):
+def print_msg(*args, print_to: Optional[str] = "debug"):
+    """
+    Print ``*args`` to the ``print_to`` target:
+      - None: print nothing
+      - debug: print() to stderr with "DEBUG:" prefix if config["debug"] is set
+      - verbose: print() to stdout if config["verbose"] or config["debug"] is set
+      - error: print() to stderr with red "ERROR:" prefix
+      - warning: print() to stderr with yellow "WARNING:" prefix
+      - stdout: print() to stdout
+      - stderr: print() to stderr
+    """
     from .. import conf
 
     if print_to is None:
@@ -14,6 +27,10 @@ def print_msg(*args, print_to="debug"):
         # print a verbose message to stdout if config["verbose"] or config["debug"] is set
         if conf.config["verbose"] or conf.config["debug"]:
             print(*args)
+    elif print_to == "error":
+        print(tty.colorize("ERROR:", "red,bold"), *args, file=sys.stderr)
+    elif print_to == "warning":
+        print(tty.colorize("WARNING:", "yellow,bold"), *args, file=sys.stderr)
     elif print_to == "stdout":
         # print the message to stdout
         print(*args)
@@ -22,5 +39,3 @@ def print_msg(*args, print_to="debug"):
         print(*args, file=sys.stderr)
     else:
         raise ValueError(f"Invalid value of the 'print_to' option: {print_to}")
-
-

tests/test_output.py

@@ -5,6 +5,7 @@ import unittest
 import osc.conf
 from osc.output import KeyValueTable
 from osc.output import print_msg
+from osc.output import tty
 
 
 class TestKeyValueTable(unittest.TestCase):
@@ -118,6 +119,22 @@ class TestPrintMsg(unittest.TestCase):
         self.assertEqual("foo bar\n", stdout.getvalue())
         self.assertEqual("", stderr.getvalue())
 
+    def test_error(self):
+        stdout = io.StringIO()
+        stderr = io.StringIO()
+        with contextlib.redirect_stdout(stdout), contextlib.redirect_stderr(stderr):
+            print_msg("foo", "bar", print_to="error")
+        self.assertEqual("", stdout.getvalue())
+        self.assertEqual(f"{tty.colorize('ERROR:', 'red,bold')} foo bar\n", stderr.getvalue())
+
+    def test_warning(self):
+        stdout = io.StringIO()
+        stderr = io.StringIO()
+        with contextlib.redirect_stdout(stdout), contextlib.redirect_stderr(stderr):
+            print_msg("foo", "bar", print_to="warning")
+        self.assertEqual("", stdout.getvalue())
+        self.assertEqual(f"{tty.colorize('WARNING:', 'yellow,bold')} foo bar\n", stderr.getvalue())
+
     def test_none(self):
         stdout = io.StringIO()
         stderr = io.StringIO()
@@ -134,6 +151,14 @@ class TestPrintMsg(unittest.TestCase):
         self.assertEqual("foo bar\n", stdout.getvalue())
         self.assertEqual("", stderr.getvalue())
 
+    def test_stderr(self):
+        stdout = io.StringIO()
+        stderr = io.StringIO()
+        with contextlib.redirect_stdout(stdout), contextlib.redirect_stderr(stderr):
+            print_msg("foo", "bar", print_to="stderr")
+        self.assertEqual("", stdout.getvalue())
+        self.assertEqual("foo bar\n", stderr.getvalue())
+
 
 if __name__ == "__main__":
     unittest.main()