Rich utils improvements

cmd2/cmd2.py

@@ -292,7 +292,6 @@ class Cmd(cmd.Cmd):
     Line-oriented command interpreters are often useful for test harnesses, internal tools, and rapid prototypes.
     """
 
-    ruler = "─"
     DEFAULT_EDITOR = utils.find_editor()
 
     # Sorting keys for strings
@@ -475,7 +474,10 @@ def __init__(
         # The multiline command currently being typed which is used to tab complete multiline commands.
         self._multiline_in_progress = ''
 
-        # Set text which prints right before all of the help topics are listed.
+        # Characters used to draw a horizontal rule. Should not be blank.
+        self.ruler = "─"
+
+        # Set text which prints right before all of the help tables are listed.
         self.doc_leader = ""
 
         # Set header for table listing documented commands.
@@ -4175,8 +4177,7 @@ def print_topics(self, header: str, cmds: list[str] | None, cmdlen: int, maxcol:
 
         header_grid = Table.grid()
         header_grid.add_row(header, style=Cmd2Style.HELP_HEADER)
-        if self.ruler:
-            header_grid.add_row(Rule(characters=self.ruler))
+        header_grid.add_row(Rule(characters=self.ruler))
         self.poutput(header_grid)
         self.columnize(cmds, maxcol - 1)
         self.poutput()
@@ -5543,7 +5544,10 @@ class TestMyAppCase(Cmd2TestCase):
         verinfo = ".".join(map(str, sys.version_info[:3]))
         num_transcripts = len(transcripts_expanded)
         plural = '' if len(transcripts_expanded) == 1 else 's'
-        self.poutput(su.align_center(' cmd2 transcript test ', character=self.ruler), style=Style(bold=True))
+        self.poutput(
+            Rule("cmd2 transcript test", style=Style.null()),
+            style=Style(bold=True),
+        )
         self.poutput(f'platform {sys.platform} -- Python {verinfo}, cmd2-{cmd2.__version__}, readline-{rl_type}')
         self.poutput(f'cwd: {os.getcwd()}')
         self.poutput(f'cmd2 app: {sys.argv[0]}')
@@ -5559,9 +5563,8 @@ class TestMyAppCase(Cmd2TestCase):
         execution_time = time.time() - start_time
         if test_results.wasSuccessful():
             self.perror(stream.read(), end="", style=None)
-            finish_msg = f' {num_transcripts} transcript{plural} passed in {execution_time:.3f} seconds '
-            finish_msg = su.align_center(finish_msg, character=self.ruler)
-            self.psuccess(finish_msg)
+            finish_msg = f'{num_transcripts} transcript{plural} passed in {execution_time:.3f} seconds'
+            self.psuccess(Rule(finish_msg, style=Style.null()))
         else:
             # Strip off the initial traceback which isn't particularly useful for end users
             error_str = stream.read()

cmd2/rich_utils.py

@@ -1,4 +1,4 @@
-"""Provides common utilities to support Rich in cmd2 applications."""
+"""Provides common utilities to support Rich in cmd2-based applications."""
 
 from collections.abc import Mapping
 from enum import Enum
@@ -17,7 +17,6 @@
     RichCast,
 )
 from rich.style import (
-    Style,
     StyleType,
 )
 from rich.text import Text
@@ -47,47 +46,44 @@ def __repr__(self) -> str:
 ALLOW_STYLE = AllowStyle.TERMINAL
 
 
-class Cmd2Theme(Theme):
-    """Rich theme class used by cmd2."""
+def _create_default_theme() -> Theme:
+    """Create a default theme for cmd2-based applications.
 
-    def __init__(self, styles: Mapping[str, StyleType] | None = None) -> None:
-        """Cmd2Theme initializer.
+    This theme combines the default styles from cmd2, rich-argparse, and Rich.
+    """
+    app_styles = DEFAULT_CMD2_STYLES.copy()
+    app_styles.update(RichHelpFormatter.styles.copy())
+    return Theme(app_styles, inherit=True)
 
-        :param styles: optional mapping of style names on to styles.
-                       Defaults to None for a theme with no styles.
-        """
-        cmd2_styles = DEFAULT_CMD2_STYLES.copy()
 
-        # Include default styles from rich-argparse
-        cmd2_styles.update(RichHelpFormatter.styles.copy())
+def set_theme(styles: Mapping[str, StyleType] | None = None) -> None:
+    """Set the Rich theme used by cmd2.
 
-        if styles is not None:
-            cmd2_styles.update(styles)
+    Call set_theme() with no arguments to reset to the default theme.
+    This will clear any custom styles that were previously applied.
 
-        # Set inherit to True to include Rich's default styles
-        super().__init__(cmd2_styles, inherit=True)
+    :param styles: optional mapping of style names to styles
+    """
+    global APP_THEME  # noqa: PLW0603
 
+    # Start with a fresh copy of the default styles.
+    app_styles: dict[str, StyleType] = {}
+    app_styles.update(_create_default_theme().styles)
 
-# Current Rich theme used by Cmd2Console
-THEME: Cmd2Theme = Cmd2Theme()
+    # Incorporate custom styles.
+    if styles is not None:
+        app_styles.update(styles)
 
+    APP_THEME = Theme(app_styles)
 
-def set_theme(new_theme: Cmd2Theme) -> None:
-    """Set the Rich theme used by cmd2.
+    # Synchronize rich-argparse styles with the main application theme.
+    for name in RichHelpFormatter.styles.keys() & APP_THEME.styles.keys():
+        RichHelpFormatter.styles[name] = APP_THEME.styles[name]
 
-    :param new_theme: new theme to use.
-    """
-    global THEME  # noqa: PLW0603
-    THEME = new_theme
-
-    # Make sure the new theme has all style names included in a Cmd2Theme.
-    missing_names = Cmd2Theme().styles.keys() - THEME.styles.keys()
-    for name in missing_names:
-        THEME.styles[name] = Style()
 
-    # Update rich-argparse styles
-    for name in RichHelpFormatter.styles.keys() & THEME.styles.keys():
-        RichHelpFormatter.styles[name] = THEME.styles[name]
+# The main theme for cmd2-based applications.
+# You can change it with set_theme().
+APP_THEME = _create_default_theme()
 
 
 class RichPrintKwargs(TypedDict, total=False):
@@ -113,7 +109,7 @@ class RichPrintKwargs(TypedDict, total=False):
 
 
 class Cmd2Console(Console):
-    """Rich console with characteristics appropriate for cmd2 applications."""
+    """Rich console with characteristics appropriate for cmd2-based applications."""
 
     def __init__(self, file: IO[str] | None = None) -> None:
         """Cmd2Console initializer.
@@ -147,7 +143,7 @@ def __init__(self, file: IO[str] | None = None) -> None:
             markup=False,
             emoji=False,
             highlight=False,
-            theme=THEME,
+            theme=APP_THEME,
         )
 
     def on_broken_pipe(self) -> None:
@@ -178,13 +174,17 @@ def rich_text_to_string(text: Text) -> str:
         markup=False,
         emoji=False,
         highlight=False,
-        theme=THEME,
+        theme=APP_THEME,
     )
     with console.capture() as capture:
         console.print(text, end="")
     return capture.get()
 
 
+# If True, Rich still has the bug addressed in string_to_rich_text().
+_from_ansi_has_newline_bug = Text.from_ansi("\n").plain == ""
+
+
 def string_to_rich_text(text: str) -> Text:
     r"""Create a Text object from a string which can contain ANSI escape codes.
 
@@ -199,24 +199,25 @@ def string_to_rich_text(text: str) -> Text:
     """
     result = Text.from_ansi(text)
 
-    # If the original string ends with a recognized line break character,
-    # then restore the missing newline. We use "\n" because Text.from_ansi()
-    # converts all line breaks into newlines.
-    # Source: https://docs.python.org/3/library/stdtypes.html#str.splitlines
-    line_break_chars = {
-        "\n",  # Line Feed
-        "\r",  # Carriage Return
-        "\v",  # Vertical Tab
-        "\f",  # Form Feed
-        "\x1c",  # File Separator
-        "\x1d",  # Group Separator
-        "\x1e",  # Record Separator
-        "\x85",  # Next Line (NEL)
-        "\u2028",  # Line Separator
-        "\u2029",  # Paragraph Separator
-    }
-    if text and text[-1] in line_break_chars:
-        result.append("\n")
+    if _from_ansi_has_newline_bug:
+        # If the original string ends with a recognized line break character,
+        # then restore the missing newline. We use "\n" because Text.from_ansi()
+        # converts all line breaks into newlines.
+        # Source: https://docs.python.org/3/library/stdtypes.html#str.splitlines
+        line_break_chars = {
+            "\n",  # Line Feed
+            "\r",  # Carriage Return
+            "\v",  # Vertical Tab
+            "\f",  # Form Feed
+            "\x1c",  # File Separator
+            "\x1d",  # Group Separator
+            "\x1e",  # Record Separator
+            "\x85",  # Next Line (NEL)
+            "\u2028",  # Line Separator
+            "\u2029",  # Paragraph Separator
+        }
+        if text and text[-1] in line_break_chars:
+            result.append("\n")
 
     return result
 

cmd2/styles.py

@@ -30,13 +30,13 @@ class Cmd2Style(StrEnum):
     added here must have a corresponding style definition there.
     """
 
-    ERROR = "cmd2.error"
-    EXAMPLE = "cmd2.example"
-    HELP_HEADER = "cmd2.help.header"
-    HELP_LEADER = "cmd2.help.leader"
-    RULE_LINE = "cmd2.rule.line"
-    SUCCESS = "cmd2.success"
-    WARNING = "cmd2.warning"
+    ERROR = "cmd2.error"  # Error text (used by perror())
+    EXAMPLE = "cmd2.example"  # Command line examples in help text
+    HELP_HEADER = "cmd2.help.header"  # Help table header text
+    HELP_LEADER = "cmd2.help.leader"  # Text right before the help tables are listed
+    RULE_LINE = "rule.line"  # Rich style for horizontal rules
+    SUCCESS = "cmd2.success"  # Success text (used by psuccess())
+    WARNING = "cmd2.warning"  # Warning text (used by pwarning())
 
 
 # Default styles used by cmd2. Tightly coupled with the Cmd2Style enum.

tests/test_rich_utils.py

@@ -0,0 +1,85 @@
+"""Unit testing for cmd2/rich_utils.py module"""
+
+import pytest
+from rich.style import Style
+from rich.text import Text
+
+from cmd2 import (
+    Cmd2Style,
+    Color,
+)
+from cmd2 import rich_utils as ru
+from cmd2 import string_utils as su
+
+
+def test_string_to_rich_text() -> None:
+    # Line breaks recognized by str.splitlines().
+    # Source: https://docs.python.org/3/library/stdtypes.html#str.splitlines
+    line_breaks = {
+        "\n",  # Line Feed
+        "\r",  # Carriage Return
+        "\r\n",  # Carriage Return + Line Feed
+        "\v",  # Vertical Tab
+        "\f",  # Form Feed
+        "\x1c",  # File Separator
+        "\x1d",  # Group Separator
+        "\x1e",  # Record Separator
+        "\x85",  # Next Line (NEL)
+        "\u2028",  # Line Separator
+        "\u2029",  # Paragraph Separator
+    }
+
+    # Test all line breaks
+    for lb in line_breaks:
+        input_string = f"Text{lb}"
+        expected_output = input_string.replace(lb, "\n")
+        assert ru.string_to_rich_text(input_string).plain == expected_output
+
+    # Test string without trailing line break
+    input_string = "No trailing\nline break"
+    assert ru.string_to_rich_text(input_string).plain == input_string
+
+    # Test empty string
+    input_string = ""
+    assert ru.string_to_rich_text(input_string).plain == input_string
+
+
+@pytest.mark.parametrize(
+    ('rich_text', 'string'),
+    [
+        (Text("Hello"), "Hello"),
+        (Text("Hello\n"), "Hello\n"),
+        (Text("Hello", style="blue"), su.stylize("Hello", style="blue")),
+    ],
+)
+def test_rich_text_to_string(rich_text: Text, string: str) -> None:
+    assert ru.rich_text_to_string(rich_text) == string
+
+
+def test_set_style() -> None:
+    # Save a cmd2, rich-argparse, and rich-specific style.
+    cmd2_style_key = Cmd2Style.ERROR
+    argparse_style_key = "argparse.args"
+    rich_style_key = "inspect.attr"
+
+    orig_cmd2_style = ru.APP_THEME.styles[cmd2_style_key]
+    orig_argparse_style = ru.APP_THEME.styles[argparse_style_key]
+    orig_rich_style = ru.APP_THEME.styles[rich_style_key]
+
+    # Overwrite these styles by setting a new theme.
+    theme = {
+        cmd2_style_key: Style(color=Color.CYAN),
+        argparse_style_key: Style(color=Color.AQUAMARINE3, underline=True),
+        rich_style_key: Style(color=Color.DARK_GOLDENROD, bold=True),
+    }
+    ru.set_theme(theme)
+
+    # Verify theme styles have changed to our custom values.
+    assert ru.APP_THEME.styles[cmd2_style_key] != orig_cmd2_style
+    assert ru.APP_THEME.styles[cmd2_style_key] == theme[cmd2_style_key]
+
+    assert ru.APP_THEME.styles[argparse_style_key] != orig_argparse_style
+    assert ru.APP_THEME.styles[argparse_style_key] == theme[argparse_style_key]
+
+    assert ru.APP_THEME.styles[rich_style_key] != orig_rich_style
+    assert ru.APP_THEME.styles[rich_style_key] == theme[rich_style_key]