Add history delete #4929 (#5172)

* Add `history delete` #4929

* Add news and satisfy linter.

* Added `history delete` for sqlite backend

* Format with black.

* Use REGEXP instead of LIKE for sqlite backend.

* History delete: iterate over entries for sqlite backend.

* Use '='-operator instead of LIKE.

news/add_history_delete.rst

@@ -0,0 +1,23 @@
+**Added:**
+
+* Added ``history delete`` command to both the JSON and SQLite history backends allowing users to delete commands from history that matches a pattern.
+
+**Changed:**
+
+* <news item>
+
+**Deprecated:**
+
+* <news item>
+
+**Removed:**
+
+* <news item>
+
+**Fixed:**
+
+* <news item>
+
+**Security:**
+
+* <news item>

xonsh/history/base.py

@@ -174,6 +174,22 @@ class History:
         """
         pass
 
+    def delete(self, pattern):
+        """Deletes the history of the current session for commands that match
+        a user-provided pattern.
+
+        Parameters
+        ----------
+        pattern: str
+            The regex pattern to match commands against.
+
+        Returns
+        -------
+        int
+            The number of commands deleted from history.
+        """
+        pass
+
     @functools.cached_property
     def ignore_regex(self):
         compiled_regex = None

xonsh/history/json.py

@@ -2,6 +2,7 @@
 import collections
 import collections.abc as cabc
 import os
+import re
 import sys
 import threading
 import time
@@ -10,9 +11,13 @@ from xonsh.built_ins import XSH
 
 try:
     import ujson as json
+
+    JSONDecodeError = json.JSONDecodeError  # type: ignore
 except ImportError:
     import json  # type: ignore
 
+    JSONDecodeError = json.decoder.JSONDecodeError  # type: ignore
+
 import xonsh.lazyjson as xlj
 import xonsh.tools as xt
 import xonsh.xoreutils.uptime as uptime
@@ -549,7 +554,7 @@ class JsonHistory(History):
                 continue
             try:
                 commands = json_file.load()["cmds"]
-            except (json.decoder.JSONDecodeError, ValueError):
+            except (JSONDecodeError, ValueError):
                 # file is corrupted somehow
                 if XSH.env.get("XONSH_DEBUG") > 0:
                     msg = "xonsh history file {0!r} is not valid JSON"
@@ -596,3 +601,43 @@ class JsonHistory(History):
 
         # Flush empty history object to disk, overwriting previous data.
         self.flush()
+
+    def delete(self, pattern):
+        """Deletes all entries in history which matches a pattern."""
+        pattern = re.compile(pattern)
+
+        deleted = 0
+        # First, delete any matching commands in the in-memory buffer.
+        for i, cmd in enumerate(self.buffer):
+            if pattern.match(cmd["inp"]):
+                del self.buffer[i]
+                deleted += 1
+
+        # Then, delete any matching commands on disk.
+        while self.gc and self.gc.is_alive():
+            time.sleep(0.011)  # gc sleeps for 0.01 secs, sleep a beat longer
+        for f in _xhj_get_history_files():
+            try:
+                json_file = xlj.LazyJSON(f, reopen=False)
+            except ValueError:
+                # Invalid json file
+                continue
+            try:
+                file_content = json_file.load()
+                commands = file_content["cmds"]
+                for i, c in enumerate(commands):
+                    if pattern.match(c["inp"]):
+                        del commands[i]
+                        deleted += 1
+
+                file_content["cmds"] = commands
+                with open(f, "w") as fp:
+                    xlj.ljdump(file_content, fp)
+            except (JSONDecodeError, ValueError):
+                # file is corrupted somehow
+                if XSH.env.get("XONSH_DEBUG") > 0:
+                    msg = "xonsh history file {0!r} is not valid JSON"
+                    print(msg.format(f), file=sys.stderr)
+                continue
+
+        return deleted

xonsh/history/main.py

@@ -339,6 +339,19 @@ class HistoryAlias(xcli.ArgParserAlias):
         hist.clear()
         print("History cleared", file=sys.stderr)
 
+    @staticmethod
+    def delete(pattern):
+        """Delete all commands matching a pattern
+
+        Parameters
+        ----------
+        pattern:
+            regex pattern to match against command history
+        """
+        hist = XSH.history
+        deleted = hist.delete(pattern)
+        print(f"Deleted {deleted} entries from history")
+
     @staticmethod
     def file(_stdout):
         """Display the current history filename"""
@@ -466,6 +479,7 @@ class HistoryAlias(xcli.ArgParserAlias):
         parser.add_command(self.off)
         parser.add_command(self.on)
         parser.add_command(self.clear)
+        parser.add_command(self.delete)
         parser.add_command(self.gc)
         parser.add_command(self.transfer)
 

xonsh/history/sqlite.py

@@ -2,6 +2,7 @@
 import collections
 import json
 import os
+import re
 import sqlite3
 import sys
 import threading
@@ -220,6 +221,17 @@ def xh_sqlite_wipe_session(sessionid=None, filename=None):
         c.execute(sql, (str(sessionid),))
 
 
+def xh_sqlite_delete_input_matching(pattern, filename=None):
+    """Deletes entries from the database where the input matches a pattern."""
+    with _xh_sqlite_get_conn(filename=filename) as conn:
+        c = conn.cursor()
+        _xh_sqlite_create_history_table(c)
+        for inp, *_ in _xh_sqlite_get_records(c):
+            if pattern.match(inp):
+                sql = f"DELETE FROM xonsh_history WHERE inp = '{inp}'"
+                c.execute(sql)
+
+
 class SqliteHistoryGC(threading.Thread):
     """Shell history garbage collection."""
 
@@ -385,3 +397,9 @@ class SqliteHistory(History):
         self.cwds = []
 
         xh_sqlite_wipe_session(sessionid=self.sessionid, filename=self.filename)
+
+    def delete(self, pattern):
+        """Deletes all entries in the database where the input matches a pattern."""
+        xh_sqlite_delete_input_matching(
+            pattern=re.compile(pattern), filename=self.filename
+        )