Merge branch 'nicolasavru-support-right-prompt-function2'

tests/test_tools.py

@@ -14,7 +14,8 @@ from xonsh.tools import (
     ensure_string, is_env_path, str_to_env_path, env_path_to_str,
     escape_windows_cmd_string, is_bool, to_bool, bool_to_str,
     is_bool_or_int, to_bool_or_int, bool_or_int_to_str,
-    ensure_int_or_slice, is_float, is_string, check_for_partial_string,
+    ensure_int_or_slice, is_float, is_string, is_callable,
+    is_string_or_callable, check_for_partial_string,
     is_dynamic_cwd_width, to_dynamic_cwd_tuple, dynamic_cwd_tuple_to_str,
     argvquote, executables_in, find_next_break, expand_case_matching)
 
@@ -333,6 +334,17 @@ def test_is_string():
     yield assert_false, is_string(42.0)
 
 
+def test_is_callable():
+    yield assert_true, is_callable(lambda: 42.0)
+    yield assert_false, is_callable(42.0)
+
+
+def test_is_string_or_callable():
+    yield assert_true, is_string_or_callable('42.0')
+    yield assert_true, is_string_or_callable(lambda: 42.0)
+    yield assert_false, is_string(42.0)
+
+
 def test_always_true():
     yield assert_true, always_true(42)
     yield assert_true, always_true('42')

xonsh/environ.py

@@ -29,7 +29,8 @@ from xonsh.tools import (
     IS_SUPERUSER, always_true, always_false, ensure_string, is_env_path,
     str_to_env_path, env_path_to_str, is_bool, to_bool, bool_to_str,
     is_history_tuple, to_history_tuple, history_tuple_to_str, is_float,
-    is_string, is_completions_display_value, to_completions_display_value,
+    is_string, is_callable, is_string_or_callable,
+    is_completions_display_value, to_completions_display_value,
     is_string_set, csv_to_set, set_to_csv, get_sep, is_int, is_bool_seq,
     is_bool_or_int, to_bool_or_int, bool_or_int_to_str,
     csv_to_bool_seq, bool_seq_to_csv, DefaultNotGiven, print_exception,
@@ -104,11 +105,13 @@ DEFAULT_ENSURERS = {
     'LOADED_CONFIG': (is_bool, to_bool, bool_to_str),
     'LOADED_RC_FILES': (is_bool_seq, csv_to_bool_seq, bool_seq_to_csv),
     'MOUSE_SUPPORT': (is_bool, to_bool, bool_to_str),
+    'MULTILINE_PROMPT': (is_string_or_callable, ensure_string, ensure_string),
     re.compile('\w*PATH$'): (is_env_path, str_to_env_path, env_path_to_str),
     'PATHEXT': (is_env_path, str_to_env_path, env_path_to_str),
     'PRETTY_PRINT_RESULTS': (is_bool, to_bool, bool_to_str),
+    'PROMPT': (is_string_or_callable, ensure_string, ensure_string),
     'RAISE_SUBPROC_ERROR': (is_bool, to_bool, bool_to_str),
-    'RIGHT_PROMPT': (is_string, ensure_string, ensure_string),
+    'RIGHT_PROMPT': (is_string_or_callable, ensure_string, ensure_string),
     'TEEPTY_PIPE_DELAY': (is_float, float, str),
     'UPDATE_OS_ENVIRON': (is_bool, to_bool, bool_to_str),
     'XONSHRC': (is_env_path, str_to_env_path, env_path_to_str),

xonsh/ptk/shell.py

@@ -143,7 +143,10 @@ class PromptToolkitShell(BaseShell):
         prompt.
         """
         p = builtins.__xonsh_env__.get('RIGHT_PROMPT')
-        if len(p) == 0:
+        # partial_format_prompt does handle empty strings properly,
+        # but this avoids descending into it in the common case of
+        # $RIGHT_PROMPT == ''.
+        if isinstance(p, str) and len(p) == 0:
             return []
         try:
             p = partial_format_prompt(p)

xonsh/tools.py

@@ -549,6 +549,16 @@ def is_string(x):
     return isinstance(x, str)
 
 
+def is_callable(x):
+    """Tests if something is callable"""
+    return callable(x)
+
+
+def is_string_or_callable(x):
+    """Tests if something is a string or callable"""
+    return is_string(x) or is_callable(x)
+
+
 def always_true(x):
     """Returns True"""
     return True