fix printing of RunShellCmdError to stderr by introducing print_error…

… function that is aware of Rich

easybuild/tools/output.py

@@ -33,6 +33,7 @@
 """
 import functools
 from collections import OrderedDict
+import sys
 
 from easybuild.tools.build_log import EasyBuildError
 from easybuild.tools.config import OUTPUT_STYLE_RICH, build_option, get_output_style
@@ -328,9 +329,7 @@ def print_checks(checks_data):
 
     if use_rich():
         console = Console()
-        # don't use console.print, which causes SyntaxError in Python 2
-        console_print = getattr(console, 'print')  # noqa: B009
-        console_print('')
+        console.print('')
 
     for section in checks_data:
         section_checks = checks_data[section]
@@ -382,11 +381,25 @@ def print_checks(checks_data):
             lines.append('')
 
         if use_rich():
-            console_print(table)
+            console.print(table)
         else:
             print('\n'.join(lines))
 
 
+def print_error(error_msg, rich_highlight=True):
+    """
+    Print error message, using a Rich Console instance if possible.
+    Newlines before/after message are automatically added.
+
+    :param rich_highlight: boolean indicating whether automatic highlighting by Rich should be enabled
+    """
+    if use_rich():
+        console = Console(stderr=True)
+        console.print('\n\n' + error_msg + '\n', highlight=rich_highlight)
+    else:
+        sys.stderr.write('\n' + error_msg + '\n\n')
+
+
 # this constant must be defined at the end, since functions used as values need to be defined
 PROGRESS_BAR_TYPES = {
     PROGRESS_BAR_DOWNLOAD_ALL: download_all_progress_bar,

easybuild/tools/run.py

@@ -68,7 +68,7 @@
 from easybuild.tools.build_log import dry_run_msg, print_msg, time_str_since
 from easybuild.tools.config import build_option
 from easybuild.tools.hooks import RUN_SHELL_CMD, load_hooks, run_hook
-from easybuild.tools.output import COLOR_RED, COLOR_YELLOW, colorize
+from easybuild.tools.output import COLOR_RED, COLOR_YELLOW, colorize, print_error
 from easybuild.tools.utilities import trace_msg
 
 
@@ -125,7 +125,6 @@ def pad_4_spaces(msg, color=None):
         called_from_info = f"'{caller_function_name}' function in {caller_file_name} (line {caller_line_nr})"
 
         error_info = [
-            '',
             colorize("ERROR: Shell command failed!", COLOR_RED),
             pad_4_spaces(f"full command              ->  {self.cmd}"),
             pad_4_spaces(f"exit code                 ->  {self.exit_code}"),
@@ -144,9 +143,7 @@ def pad_4_spaces(msg, color=None):
         if self.cmd_sh is not None:
             error_info.append(pad_4_spaces(f"interactive shell script  ->  {self.cmd_sh}", color=COLOR_YELLOW))
 
-        error_info.append('')
-
-        sys.stderr.write('\n'.join(error_info) + '\n')
+        print_error('\n'.join(error_info), rich_highlight=False)
 
 
 def raise_run_shell_cmd_error(cmd_res):

test/framework/output.py

@@ -35,7 +35,7 @@
 from easybuild.tools.build_log import EasyBuildError
 from easybuild.tools.config import build_option, get_output_style, update_build_option
 from easybuild.tools.output import PROGRESS_BAR_EXTENSIONS, PROGRESS_BAR_TYPES
-from easybuild.tools.output import DummyRich, colorize, get_progress_bar, show_progress_bars
+from easybuild.tools.output import DummyRich, colorize, get_progress_bar, print_error, show_progress_bars
 from easybuild.tools.output import start_progress_bar, status_bar, stop_progress_bar, update_progress_bar, use_rich
 
 try:
@@ -139,6 +139,26 @@ def test_colorize(self):
 
         self.assertErrorRegex(EasyBuildError, "Unknown color: nosuchcolor", colorize, 'test', 'nosuchcolor')
 
+    def test_print_error(self):
+        """
+        Test print_error function
+        """
+        msg = "This is yellow: " + colorize("a banana", color='yellow')
+        self.mock_stderr(True)
+        self.mock_stdout(True)
+        print_error(msg)
+        stderr = self.get_stderr()
+        stdout = self.get_stdout()
+        self.mock_stderr(False)
+        self.mock_stdout(False)
+        self.assertEqual(stdout, '')
+        if HAVE_RICH:
+            # when using Rich, message printed to stderr won't have funny terminal escape characters for the color
+            expected = '\n\nThis is yellow: a banana\n\n'
+        else:
+            expected = '\nThis is yellow: \x1b[1;33ma banana\x1b[0m\n\n'
+        self.assertEqual(stderr, expected)
+
     def test_get_progress_bar(self):
         """
         Test get_progress_bar.