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authorTerry Jan Reedy <tjreedy@udel.edu>2016-05-22 23:10:31 (GMT)
committerTerry Jan Reedy <tjreedy@udel.edu>2016-05-22 23:10:31 (GMT)
commit0d9220e162f1e5f8caa3d7ebaa54665776d361a1 (patch)
treea4fa9f7cafdfc93fde86b8ffd6088d739bb93e01 /Lib/idlelib/history.py
parentdc4f7c09cc934524a763498250e30123a0d9d2c5 (diff)
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Issue #24225: Rename many idlelib/*.py and idlelib/idle_test/test_*.py files.
Diffstat (limited to 'Lib/idlelib/history.py')
-rw-r--r--Lib/idlelib/history.py104
1 files changed, 104 insertions, 0 deletions
diff --git a/Lib/idlelib/history.py b/Lib/idlelib/history.py
new file mode 100644
index 0000000..078af29
--- /dev/null
+++ b/Lib/idlelib/history.py
@@ -0,0 +1,104 @@
+"Implement Idle Shell history mechanism with History class"
+
+from idlelib.configHandler import idleConf
+
+class History:
+ ''' Implement Idle Shell history mechanism.
+
+ store - Store source statement (called from PyShell.resetoutput).
+ fetch - Fetch stored statement matching prefix already entered.
+ history_next - Bound to <<history-next>> event (default Alt-N).
+ history_prev - Bound to <<history-prev>> event (default Alt-P).
+ '''
+ def __init__(self, text):
+ '''Initialize data attributes and bind event methods.
+
+ .text - Idle wrapper of tk Text widget, with .bell().
+ .history - source statements, possibly with multiple lines.
+ .prefix - source already entered at prompt; filters history list.
+ .pointer - index into history.
+ .cyclic - wrap around history list (or not).
+ '''
+ self.text = text
+ self.history = []
+ self.prefix = None
+ self.pointer = None
+ self.cyclic = idleConf.GetOption("main", "History", "cyclic", 1, "bool")
+ text.bind("<<history-previous>>", self.history_prev)
+ text.bind("<<history-next>>", self.history_next)
+
+ def history_next(self, event):
+ "Fetch later statement; start with ealiest if cyclic."
+ self.fetch(reverse=False)
+ return "break"
+
+ def history_prev(self, event):
+ "Fetch earlier statement; start with most recent."
+ self.fetch(reverse=True)
+ return "break"
+
+ def fetch(self, reverse):
+ '''Fetch statememt and replace current line in text widget.
+
+ Set prefix and pointer as needed for successive fetches.
+ Reset them to None, None when returning to the start line.
+ Sound bell when return to start line or cannot leave a line
+ because cyclic is False.
+ '''
+ nhist = len(self.history)
+ pointer = self.pointer
+ prefix = self.prefix
+ if pointer is not None and prefix is not None:
+ if self.text.compare("insert", "!=", "end-1c") or \
+ self.text.get("iomark", "end-1c") != self.history[pointer]:
+ pointer = prefix = None
+ self.text.mark_set("insert", "end-1c") # != after cursor move
+ if pointer is None or prefix is None:
+ prefix = self.text.get("iomark", "end-1c")
+ if reverse:
+ pointer = nhist # will be decremented
+ else:
+ if self.cyclic:
+ pointer = -1 # will be incremented
+ else: # abort history_next
+ self.text.bell()
+ return
+ nprefix = len(prefix)
+ while 1:
+ pointer += -1 if reverse else 1
+ if pointer < 0 or pointer >= nhist:
+ self.text.bell()
+ if not self.cyclic and pointer < 0: # abort history_prev
+ return
+ else:
+ if self.text.get("iomark", "end-1c") != prefix:
+ self.text.delete("iomark", "end-1c")
+ self.text.insert("iomark", prefix)
+ pointer = prefix = None
+ break
+ item = self.history[pointer]
+ if item[:nprefix] == prefix and len(item) > nprefix:
+ self.text.delete("iomark", "end-1c")
+ self.text.insert("iomark", item)
+ break
+ self.text.see("insert")
+ self.text.tag_remove("sel", "1.0", "end")
+ self.pointer = pointer
+ self.prefix = prefix
+
+ def store(self, source):
+ "Store Shell input statement into history list."
+ source = source.strip()
+ if len(source) > 2:
+ # avoid duplicates
+ try:
+ self.history.remove(source)
+ except ValueError:
+ pass
+ self.history.append(source)
+ self.pointer = None
+ self.prefix = None
+
+if __name__ == "__main__":
+ from unittest import main
+ main('idlelib.idle_test.test_idlehistory', verbosity=2, exit=False)