diff --git a/lib/spack/llnl/util/argparsewriter.py b/lib/spack/llnl/util/argparsewriter.py
index f43595145e4..8ecf6acc88e 100644
--- a/lib/spack/llnl/util/argparsewriter.py
+++ b/lib/spack/llnl/util/argparsewriter.py
@@ -45,18 +45,18 @@ def __init__(self, prog, description, usage,
 class ArgparseWriter(argparse.HelpFormatter):
     """Analyzes an argparse ArgumentParser for easy generation of help."""
 
-    def __init__(self, prog, out=sys.stdout, aliases=False):
+    def __init__(self, prog, out=None, aliases=False):
         """Initializes a new ArgparseWriter instance.
 
         Parameters:
             prog (str): the program name
-            out (file object): the file to write to
+            out (file object): the file to write to (default sys.stdout)
             aliases (bool): whether or not to include subparsers for aliases
         """
         super(ArgparseWriter, self).__init__(prog)
         self.level = 0
         self.prog = prog
-        self.out = out
+        self.out = sys.stdout if out is None else out
         self.aliases = aliases
 
     def parse(self, parser, prog):
@@ -167,7 +167,7 @@ def write(self, parser):
 class ArgparseRstWriter(ArgparseWriter):
     """Write argparse output as rst sections."""
 
-    def __init__(self, prog, out=sys.stdout, aliases=False,
+    def __init__(self, prog, out=None, aliases=False,
                  rst_levels=_rst_levels):
         """Create a new ArgparseRstWriter.
 
@@ -178,6 +178,7 @@ def __init__(self, prog, out=sys.stdout, aliases=False,
             rst_levels (list of str): list of characters
                 for rst section headings
         """
+        out = sys.stdout if out is None else out
         super(ArgparseRstWriter, self).__init__(prog, out, aliases)
         self.rst_levels = rst_levels
 
diff --git a/lib/spack/llnl/util/tty/color.py b/lib/spack/llnl/util/tty/color.py
index 79f62c00403..b6f5ec782f9 100644
--- a/lib/spack/llnl/util/tty/color.py
+++ b/lib/spack/llnl/util/tty/color.py
@@ -215,20 +215,22 @@ def cextra(string):
     return len(''.join(re.findall(r'\033[^m]*m', string)))
 
 
-def cwrite(string, stream=sys.stdout, color=None):
+def cwrite(string, stream=None, color=None):
     """Replace all color expressions in string with ANSI control
        codes and write the result to the stream.  If color is
        False, this will write plain text with no color.  If True,
        then it will always write colored output.  If not supplied,
        then it will be set based on stream.isatty().
     """
+    stream = sys.stdout if stream is None else stream
     if color is None:
         color = get_color_when()
     stream.write(colorize(string, color=color))
 
 
-def cprint(string, stream=sys.stdout, color=None):
+def cprint(string, stream=None, color=None):
     """Same as cwrite, but writes a trailing newline to the stream."""
+    stream = sys.stdout if stream is None else stream
     cwrite(string + "\n", stream, color)
 
 
diff --git a/lib/spack/spack/cmd/commands.py b/lib/spack/spack/cmd/commands.py
index 3664fce477e..be934e0048b 100644
--- a/lib/spack/spack/cmd/commands.py
+++ b/lib/spack/spack/cmd/commands.py
@@ -78,9 +78,10 @@ def setup_parser(subparser):
 class SpackArgparseRstWriter(ArgparseRstWriter):
     """RST writer tailored for spack documentation."""
 
-    def __init__(self, prog, out=sys.stdout, aliases=False,
+    def __init__(self, prog, out=None, aliases=False,
                  documented_commands=[],
                  rst_levels=['-', '-', '^', '~', ':', '`']):
+        out = sys.stdout if out is None else out
         super(SpackArgparseRstWriter, self).__init__(
             prog, out, aliases, rst_levels)
         self.documented = documented_commands
diff --git a/lib/spack/spack/cmd/dependencies.py b/lib/spack/spack/cmd/dependencies.py
index 7f390341ef4..bbccbe23ee9 100644
--- a/lib/spack/spack/cmd/dependencies.py
+++ b/lib/spack/spack/cmd/dependencies.py
@@ -3,6 +3,8 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
+import sys
+
 import llnl.util.tty as tty
 from llnl.util.tty.colify import colify
 
@@ -43,7 +45,9 @@ def dependencies(parser, args):
         spec = spack.cmd.disambiguate_spec(specs[0], env)
 
         format_string = '{name}{@version}{%compiler}{/hash:7}'
-        tty.msg("Dependencies of %s" % spec.format(format_string, color=True))
+        if sys.stdout.isatty():
+            tty.msg(
+                "Dependencies of %s" % spec.format(format_string, color=True))
         deps = spack.store.db.installed_relatives(
             spec, 'children', args.transitive, deptype=args.deptype)
         if deps:
diff --git a/lib/spack/spack/cmd/dependents.py b/lib/spack/spack/cmd/dependents.py
index 89fd15ffdab..5563701801a 100644
--- a/lib/spack/spack/cmd/dependents.py
+++ b/lib/spack/spack/cmd/dependents.py
@@ -3,6 +3,8 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
+import sys
+
 import llnl.util.tty as tty
 from llnl.util.tty.colify import colify
 
@@ -84,7 +86,8 @@ def dependents(parser, args):
         spec = spack.cmd.disambiguate_spec(specs[0], env)
 
         format_string = '{name}{@version}{%compiler}{/hash:7}'
-        tty.msg("Dependents of %s" % spec.cformat(format_string))
+        if sys.stdout.isatty():
+            tty.msg("Dependents of %s" % spec.cformat(format_string))
         deps = spack.store.db.installed_relatives(
             spec, 'parents', args.transitive)
         if deps:
diff --git a/lib/spack/spack/cmd/find.py b/lib/spack/spack/cmd/find.py
index fa36e1cd267..db229aca7e3 100644
--- a/lib/spack/spack/cmd/find.py
+++ b/lib/spack/spack/cmd/find.py
@@ -7,6 +7,7 @@
 
 import copy
 import os
+import sys
 
 import llnl.util.tty as tty
 import llnl.util.tty.color as color
@@ -236,7 +237,7 @@ def find(parser, args):
     else:
         if env:
             display_env(env, args, decorator)
-        if args.groups:
+        if sys.stdout.isatty() and args.groups:
             tty.msg("%s" % plural(len(results), 'installed package'))
         cmd.display_specs(
             results, args, decorator=decorator, all_headers=True)
diff --git a/lib/spack/spack/cmd/modules/__init__.py b/lib/spack/spack/cmd/modules/__init__.py
index 6555b8c8a7e..7d51224e146 100644
--- a/lib/spack/spack/cmd/modules/__init__.py
+++ b/lib/spack/spack/cmd/modules/__init__.py
@@ -119,8 +119,9 @@ def one_spec_or_raise(specs):
     " this command with debug output enabled for more details.")
 
 
-def loads(module_type, specs, args, out=sys.stdout):
+def loads(module_type, specs, args, out=None):
     """Prompt the list of modules associated with a list of specs"""
+    out = sys.stdout if out is None else out
 
     # Get a comprehensive list of specs
     if args.recurse_dependencies:
diff --git a/lib/spack/spack/test/cmd/find.py b/lib/spack/spack/test/cmd/find.py
index 8516569592d..8d3c68d31aa 100644
--- a/lib/spack/spack/test/cmd/find.py
+++ b/lib/spack/spack/test/cmd/find.py
@@ -324,7 +324,7 @@ def test_find_prefix_in_env(mutable_mock_env_path, install_mockery, mock_fetch,
 
 def test_find_loaded(database, working_env):
     output = find('--loaded', '--group')
-    assert output == ''  # 0 packages installed printed separately
+    assert output == ''
 
     os.environ[uenv.spack_loaded_hashes_var] = ':'.join(
         [x.dag_hash() for x in spack.store.db.query()])