Merge branch 'master' into 2.0

12 files changed, 112 insertions, 42 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5dacc331..a1abed8f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -20,9 +20,12 @@
 * Bug Fixes
     * Fixed bug where setting `always_show_hint=True` did not show a hint when completing `Settables`
     * Fixed bug in editor detection logic on Linux systems that do not have `which`
+    * Fixed bug in table creator where column headers with tabs would result in an incorrect width calculation
+    * Fixed `FileNotFoundError` which occurred when running `history --clear` and no history file existed.
 * Enhancements
     * Added `silent_startup_script` option to `cmd2.Cmd.__init__()`. If `True`, then the startup script's
       output will be suppressed. Anything written to stderr will still display.
+    * cmd2 now uses pyreadline3 when running Python 3.8 or greater on Windows  
 
 ## 1.4.0 (November 11, 2020)
 * Bug Fixes
diff --git a/Pipfile b/Pipfile
index b384709c..bfa222b6 100644
--- a/Pipfile
+++ b/Pipfile
@@ -22,7 +22,8 @@ ipython = "*"
 isort = "*"
 mock = {version = "*",markers = "python_version < '3.6'"}
 plumbum = "*"
-pyreadline = {version = "*",sys_platform = "== 'win32'"}
+pyreadline = {version = "*",sys_platform = "== 'win32'",markers = "python_version < '3.8'"}
+pyreadline3 = {version = "*",sys_platform = "== 'win32'",markers = "python_version >= '3.8'"}
 pytest = "*"
 pytest-cov = "*"
 pytest-mock = "*"
diff --git a/cmd2/cmd2.py b/cmd2/cmd2.py
index ef82c196..27746323 100644
--- a/cmd2/cmd2.py
+++ b/cmd2/cmd2.py
@@ -4049,7 +4049,13 @@ class Cmd(cmd.Cmd):
             self.history.clear()
 
             if self.persistent_history_file:
-                os.remove(self.persistent_history_file)
+                try:
+                    os.remove(self.persistent_history_file)
+                except FileNotFoundError:
+                    pass
+                except OSError as ex:
+                    self.pexcept("Error removing history file '{}': {}".format(self.persistent_history_file, ex))
+                    return
 
             if rl_type != RlType.NONE:
                 readline.clear_history()
diff --git a/cmd2/rl_utils.py b/cmd2/rl_utils.py
index e435c3f5..ca75fd8a 100644
--- a/cmd2/rl_utils.py
+++ b/cmd2/rl_utils.py
@@ -37,8 +37,8 @@ vt100_support = False
 # Explanation for why readline wasn't loaded
 _rl_warn_reason = ''
 
-# The order of this check matters since importing pyreadline will also show readline in the modules list
-if 'pyreadline' in sys.modules:
+# The order of this check matters since importing pyreadline/pyreadline3 will also show readline in the modules list
+if 'pyreadline' in sys.modules or 'pyreadline3' in sys.modules:
     rl_type = RlType.PYREADLINE
 
     from ctypes import byref
diff --git a/cmd2/table_creator.py b/cmd2/table_creator.py
index 419f12b4..5d6b444d 100644
--- a/cmd2/table_creator.py
+++ b/cmd2/table_creator.py
@@ -83,7 +83,7 @@ class Column:
         :param header: label for column header
         :param width: display width of column. This does not account for any borders or padding which
                       may be added (e.g pre_line, inter_cell, and post_line). Header and data text wrap within
-                      this width using word-based wrapping (defaults to width of header or 1 if header is blank)
+                      this width using word-based wrapping (defaults to actual width of header or 1 if header is blank)
         :param header_horiz_align: horizontal alignment of header cells (defaults to left)
         :param header_vert_align: vertical alignment of header cells (defaults to bottom)
         :param data_horiz_align: horizontal alignment of data cells (defaults to left)
@@ -95,12 +95,7 @@ class Column:
         """
         self.header = header
 
-        if width is None:
-            # Use the width of the widest line in the header or 1 if the header has no width
-            line_widths = [ansi.style_aware_wcswidth(line) for line in self.header.splitlines()]
-            line_widths.append(1)
-            self.width = max(line_widths)
-        elif width < 1:
+        if width is not None and width < 1:
             raise ValueError("Column width cannot be less than 1")
         else:
             self.width = width
@@ -137,12 +132,28 @@ class TableCreator:
         :param cols: column definitions for this table
         :param tab_width: all tabs will be replaced with this many spaces. If a row's fill_char is a tab,
                           then it will be converted to one space.
+        :raises: ValueError if tab_width is less than 1
         """
+        if tab_width < 1:
+            raise ValueError("Tab width cannot be less than 1")
+
         self.cols = copy.copy(cols)
         self.tab_width = tab_width
 
+        for col in self.cols:
+            # Replace tabs before calculating width of header strings
+            col.header = col.header.replace('\t', SPACE * self.tab_width)
+
+            # For headers with the width not yet set, use the width of the
+            # widest line in the header or 1 if the header has no width
+            if col.width is None:
+                line_widths = [ansi.style_aware_wcswidth(line) for line in col.header.splitlines()]
+                line_widths.append(1)
+                col.width = max(line_widths)
+
     @staticmethod
-    def _wrap_long_word(word: str, max_width: int, max_lines: Union[int, float], is_last_word: bool) -> Tuple[str, int, int]:
+    def _wrap_long_word(word: str, max_width: int, max_lines: Union[int, float],
+                        is_last_word: bool) -> Tuple[str, int, int]:
         """
         Used by _wrap_text() to wrap a long word over multiple lines
 
@@ -351,14 +362,16 @@ class TableCreator:
 
             # Stop line loop if we've written to max_lines
             if total_lines == max_lines:
-                # If this isn't the last data line and there is space left on the final wrapped line, then add an ellipsis
+                # If this isn't the last data line and there is space
+                # left on the final wrapped line, then add an ellipsis
                 if data_line_index < len(data_str_lines) - 1 and cur_line_width < max_width:
                     wrapped_buf.write(constants.HORIZONTAL_ELLIPSIS)
                 break
 
         return wrapped_buf.getvalue()
 
-    def _generate_cell_lines(self, cell_data: Any, is_header: bool, col: Column, fill_char: str) -> Tuple[Deque[str], int]:
+    def _generate_cell_lines(self, cell_data: Any, is_header: bool,
+                             col: Column, fill_char: str) -> Tuple[Deque[str], int]:
         """
         Generate the lines of a table cell
 
@@ -398,14 +411,14 @@ class TableCreator:
 
         :param row_data: If this is None then a header row is generated. Otherwise data should have an entry for each
                          column in the row. (Defaults to None)
-        :param fill_char: character that fills remaining space in a cell. Defaults to space. If this is a tab, then it will
-                          be converted to one space. (Cannot be a line breaking character)
+        :param fill_char: character that fills remaining space in a cell. Defaults to space. If this is a tab,
+                          then it will be converted to one space. (Cannot be a line breaking character)
         :param pre_line: string to print before each line of a row. This can be used for a left row border and
                          padding before the first cell's text. (Defaults to blank)
         :param inter_cell: string to print where two cells meet. This can be used for a border between cells and padding
                            between it and the 2 cells' text. (Defaults to 2 spaces)
-        :param post_line: string to print after each line of a row. This can be used for padding after the last cell's text
-                          and a right row border. (Defaults to blank)
+        :param post_line: string to print after each line of a row. This can be used for padding after
+                          the last cell's text and a right row border. (Defaults to blank)
         :return: row string
         :raises: ValueError if data isn't the same length as self.cols
         :raises: TypeError if fill_char is more than one character (not including ANSI style sequences)
@@ -608,7 +621,8 @@ class SimpleTable(TableCreator):
         :param table_data: Data with an entry for each data row of the table. Each entry should have data for
                            each column in the row.
         :param include_header: If True, then a header will be included at top of table. (Defaults to True)
-        :param row_spacing: A number 0 or greater specifying how many blank lines to place between each row (Defaults to 1)
+        :param row_spacing: A number 0 or greater specifying how many blank lines to place between
+                            each row (Defaults to 1)
         :raises: ValueError if row_spacing is less than 0
         """
         if row_spacing < 0:
@@ -820,8 +834,8 @@ class BorderedTable(TableCreator):
 
 class AlternatingTable(BorderedTable):
     """
-    Implementation of BorderedTable which uses background colors to distinguish between rows instead of row border lines.
-    This class can be used to create the whole table at once or one row at a time.
+    Implementation of BorderedTable which uses background colors to distinguish between rows instead of row border
+    lines. This class can be used to create the whole table at once or one row at a time.
     """
     def __init__(self, cols: Sequence[Column], *, tab_width: int = 4, column_borders: bool = True, padding: int = 1,
                  bg_odd: Optional[ansi.bg] = None, bg_even: Optional[ansi.bg] = ansi.bg.bright_black) -> None:
diff --git a/docs/features/commands.rst b/docs/features/commands.rst
index 8e61a472..cc603f70 100644
--- a/docs/features/commands.rst
+++ b/docs/features/commands.rst
@@ -127,7 +127,7 @@ without errors), and that ``cmd2`` should prompt the user for more input.
 If you return ``True`` from a command method, that indicates to ``cmd2`` that
 it should stop prompting for user input and cleanly exit. ``cmd2`` already
 includes a ``quit`` command, but if you wanted to make another one called
-``finis`` you could::
+``finish`` you could::
 
     def do_finish(self, line):
         """Exit the application"""
@@ -156,7 +156,7 @@ system shell::
         """A simple cmd2 application."""
 
     def do_bail(self, line):
-        """Exit the application""
+        """Exit the application"""
         self.perror("fatal error, exiting")
         self.exit_code = 2
         return true
diff --git a/docs/features/modular_commands.rst b/docs/features/modular_commands.rst
index 790b933e..8bd9ba2f 100644
--- a/docs/features/modular_commands.rst
+++ b/docs/features/modular_commands.rst
@@ -29,7 +29,7 @@ Features
 
 See API documentation for :attr:`cmd2.command_definition.CommandSet`
 
-See the examples for more details: https://github.com/python-cmd2/cmd2/tree/master/plugins/command_sets/examples
+See [the examples](https://github.com/python-cmd2/cmd2/tree/master/examples/modular_commands) for more details.
 
 
 Defining Commands
diff --git a/docs/features/startup_commands.rst b/docs/features/startup_commands.rst
index aaaf7722..f105054b 100644
--- a/docs/features/startup_commands.rst
+++ b/docs/features/startup_commands.rst
@@ -64,3 +64,12 @@ like so::
 This text file should contain a :ref:`Command Script
 <features/scripting:Command Scripts>`. See the AliasStartup_ example for a
 demonstration.
+
+You can silence a startup script's output by setting ``silent_startup_script``
+to True::
+
+    cmd2.Cmd.__init__(self, startup_script='.cmd2rc', silent_startup_script=True)
+
+Anything written to stderr will still print. Additionally, a startup script
+cannot be silenced if ``allow_redirection`` is False since silencing works
+by redirecting a script's output to ``os.devnull``.
diff --git a/docs/overview/integrating.rst b/docs/overview/integrating.rst
index db5cb206..041083bc 100644
--- a/docs/overview/integrating.rst
+++ b/docs/overview/integrating.rst
@@ -26,10 +26,13 @@ Windows Considerations
 
 If you would like to use :ref:`features/completion:Completion`, and you want
 your application to run on Windows, you will need to ensure you install the
-``pyreadline`` package. Make sure to include the following in your
-``setup.py``::
+``pyreadline3`` or ``pyreadline`` package. Make sure to include the following
+in your ``setup.py``::
 
   install_requires=[
     'cmd2>=1,<2',
-    ":sys_platform=='win32'": ['pyreadline'],
+    ":sys_platform=='win32'": [
+        "pyreadline ; python_version<'3.8'",
+        "pyreadline3 ; python_version>='3.8'",  # pyreadline3 is a drop-in replacement for Python 3.8 and above
+    ],
   ]
diff --git a/setup.py b/setup.py
index 5e2995a9..6b438b13 100755
--- a/setup.py
+++ b/setup.py
@@ -44,8 +44,9 @@ INSTALL_REQUIRES = [
 ]
 
 EXTRAS_REQUIRE = {
-    # Windows also requires pyreadline to ensure tab completion works
-    ":sys_platform=='win32'": ['pyreadline'],
+    # Windows also requires pyreadline or the replacement, pyreadline3, to ensure tab completion works
+    ":sys_platform=='win32' and python_version<'3.8'": ["pyreadline"],
+    ":sys_platform=='win32' and python_version>='3.8'": ["pyreadline3"],
     # Extra dependencies for running unit tests
     'test': [
         "gnureadline; sys_platform=='darwin'",  # include gnureadline on macOS to ensure it is available in nox env
diff --git a/tests/test_history.py b/tests/test_history.py
index 29ca020a..49898a85 100755
--- a/tests/test_history.py
+++ b/tests/test_history.py
@@ -521,7 +521,7 @@ def test_history_run_one_command(base_app):
     out2, err2 = run_cmd(base_app, 'history -r 1')
     assert out1 == out2
 
-def test_history_clear(hist_file):
+def test_history_clear(mocker, hist_file):
     # Add commands to history
     app = cmd2.Cmd(persistent_history_file=hist_file)
     run_cmd(app, 'help')
@@ -539,6 +539,17 @@ def test_history_clear(hist_file):
     assert out == []
     assert not os.path.exists(hist_file)
 
+    # Clear the history again and make sure the FileNotFoundError from trying to delete missing history file is silent
+    run_cmd(app, 'history --clear')
+
+    # Cause os.remove to fail and make sure error gets printed
+    mock_remove = mocker.patch('os.remove')
+    mock_remove.side_effect = OSError
+
+    out, err = run_cmd(app, 'history --clear')
+    assert out == []
+    assert 'Error removing history file' in err[0]
+
 def test_history_verbose_with_other_options(base_app):
     # make sure -v shows a usage error if any other options are present
     options_to_test = ['-r', '-e', '-o file', '-t file', '-c', '-x']
diff --git a/tests/test_table_creator.py b/tests/test_table_creator.py
index 58dd6fdf..649674a4 100644
--- a/tests/test_table_creator.py
+++ b/tests/test_table_creator.py
@@ -20,18 +20,6 @@ from cmd2.table_creator import (
 
 
 def test_column_creation():
-    # No width specified, blank label
-    c = Column("")
-    assert c.width == 1
-
-    # No width specified, label isn't blank but has no width
-    c = Column(ansi.style('', fg=ansi.fg.green))
-    assert c.width == 1
-
-    # No width specified, label has width
-    c = Column("short\nreally long")
-    assert c.width == ansi.style_aware_wcswidth("really long")
-
     # Width less than 1
     with pytest.raises(ValueError) as excinfo:
         Column("Column 1", width=0)
@@ -46,6 +34,36 @@ def test_column_creation():
         Column("Column 1", max_data_lines=0)
     assert "Max data lines cannot be less than 1" in str(excinfo.value)
 
+    # No width specified, blank label
+    c = Column("")
+    assert c.width is None
+    tc = TableCreator([c])
+    assert tc.cols[0].width == 1
+
+    # No width specified, label isn't blank but has no width
+    c = Column(ansi.style('', fg=ansi.fg.green))
+    assert c.width is None
+    tc = TableCreator([c])
+    assert tc.cols[0].width == 1
+
+    # No width specified, label has width
+    c = Column("a line")
+    assert c.width is None
+    tc = TableCreator([c])
+    assert tc.cols[0].width == ansi.style_aware_wcswidth("a line")
+
+    # No width specified, label has width and multiple lines
+    c = Column("short\nreally long")
+    assert c.width is None
+    tc = TableCreator([c])
+    assert tc.cols[0].width == ansi.style_aware_wcswidth("really long")
+
+    # No width specified, label has tabs
+    c = Column("line\twith\ttabs")
+    assert c.width is None
+    tc = TableCreator([c])
+    assert tc.cols[0].width == ansi.style_aware_wcswidth("line    with    tabs")
+
 
 def test_column_alignment():
     column_1 = Column("Col 1", width=10,
@@ -241,6 +259,10 @@ def test_tabs():
                           inter_cell='\t', post_line='\t')
     assert row == '  Col  1                Col 2  '
 
+    with pytest.raises(ValueError) as excinfo:
+        TableCreator([column_1, column_2], tab_width=0)
+    assert "Tab width cannot be less than 1" in str(excinfo.value)
+
 
 def test_simple_table_creation():
     column_1 = Column("Col 1", width=16)