Merge from 3.x: PR #7132

Fixes #7080

spyder/plugins/history.py

@@ -9,6 +9,7 @@
 # Standard library imports
 import os.path as osp
 import sys
+import re
 
 # Third party imports
 from qtpy.QtCore import Signal, Slot
@@ -17,13 +18,14 @@
 
 
 # Local imports
-from spyder.utils import encoding
 from spyder.config.base import _
 from spyder.api.plugins import SpyderPluginWidget
 from spyder.api.preferences import PluginConfigPage
 from spyder.py3compat import is_text_string, to_text_string
+from spyder.utils import encoding
 from spyder.utils import icon_manager as ima
 from spyder.utils.qthelpers import add_actions, create_action
+from spyder.utils.sourcecode import normalize_eols
 from spyder.widgets.tabs import Tabs
 from spyder.widgets.sourcecode import codeeditor
 from spyder.widgets.findreplace import FindReplace
@@ -233,6 +235,12 @@ def add_history(self, filename):
         editor.toggle_wrap_mode( self.get_option('wrap') )
 
         text, _ = encoding.read(filename)
+        text = normalize_eols(text)
+        linebreaks = [m.start() for m in re.finditer('\n', text)]
+        maxNline = self.get_option('max_entries')
+        if len(linebreaks) > maxNline:
+            text = text[linebreaks[-maxNline - 1] + 1:]
+            encoding.write(text, filename)
         editor.set_text(text)
         editor.set_cursor_position('eof')
 

spyder/plugins/tests/test_history.py

@@ -9,6 +9,7 @@
 from qtpy.QtGui import QTextOption
 
 from spyder.plugins import history
+from spyder.py3compat import to_text_string
 
 #==============================================================================
 # Utillity Functions
@@ -74,6 +75,26 @@ def historylog_with_tab(historylog, mocker, monkeypatch):
 #==============================================================================
 # Tests
 #==============================================================================
+def test_max_entries(historylog, tmpdir):
+    """Test that history is truncated at max_entries."""
+    max_entries = historylog.get_option('max_entries')
+
+    # Write more than max entries in a test file
+    history = ''
+    for i in range(max_entries + 1):
+        history = history + '{}\n'.format(i)
+
+    history_file = tmpdir.join('history.py')
+    history_file.write(history)
+
+    # Load test file in plugin
+    historylog.add_history(to_text_string(history_file))
+
+    # Assert that we have max_entries after loading history and
+    # that there's no 0 in the first line
+    assert len(history_file.readlines()) == max_entries
+    assert '0' not in history_file.readlines()[0]
+
 
 def test_init(historylog):
     """Test HistoryLog.__init__.

spyder/utils/sourcecode.py

@@ -71,6 +71,14 @@ def has_mixed_eol_chars(text):
     return repr(correct_text) != repr(text)
 
 
+def normalize_eols(text, eol='\n'):
+    """Use the same eol's in text"""
+    for eol_char, _ in EOL_CHARS:
+        if eol_char != eol:
+            text = text.replace(eol_char, eol)
+    return text
+
+
 def fix_indentation(text, indent_chars):
     """Replace tabs by spaces"""
     return text.replace('\t', indent_chars)

spyder/utils/tests/test_sourcecode.py

@@ -12,6 +12,11 @@
 from spyder.utils import sourcecode
 
 
+def test_normalize_eols():
+    text = "a\nb\r\nc\rd"
+    assert sourcecode.normalize_eols(text) == "a\nb\nc\nd"
+
+
 def test_get_primary_at():
     code = 'import functools\nfunctools.partial'
     assert sourcecode.get_primary_at(code, len(code)) == 'functools.partial'