jpayne@68: '''Complete the current word before the cursor with words in the editor.
jpayne@68: 
jpayne@68: Each menu selection or shortcut key selection replaces the word with a
jpayne@68: different word with the same prefix. The search for matches begins
jpayne@68: before the target and moves toward the top of the editor. It then starts
jpayne@68: after the cursor and moves down. It then returns to the original word and
jpayne@68: the cycle starts again.
jpayne@68: 
jpayne@68: Changing the current text line or leaving the cursor in a different
jpayne@68: place before requesting the next selection causes AutoExpand to reset
jpayne@68: its state.
jpayne@68: 
jpayne@68: There is only one instance of Autoexpand.
jpayne@68: '''
jpayne@68: import re
jpayne@68: import string
jpayne@68: 
jpayne@68: 
jpayne@68: class AutoExpand:
jpayne@68:     wordchars = string.ascii_letters + string.digits + "_"
jpayne@68: 
jpayne@68:     def __init__(self, editwin):
jpayne@68:         self.text = editwin.text
jpayne@68:         self.bell = self.text.bell
jpayne@68:         self.state = None
jpayne@68: 
jpayne@68:     def expand_word_event(self, event):
jpayne@68:         "Replace the current word with the next expansion."
jpayne@68:         curinsert = self.text.index("insert")
jpayne@68:         curline = self.text.get("insert linestart", "insert lineend")
jpayne@68:         if not self.state:
jpayne@68:             words = self.getwords()
jpayne@68:             index = 0
jpayne@68:         else:
jpayne@68:             words, index, insert, line = self.state
jpayne@68:             if insert != curinsert or line != curline:
jpayne@68:                 words = self.getwords()
jpayne@68:                 index = 0
jpayne@68:         if not words:
jpayne@68:             self.bell()
jpayne@68:             return "break"
jpayne@68:         word = self.getprevword()
jpayne@68:         self.text.delete("insert - %d chars" % len(word), "insert")
jpayne@68:         newword = words[index]
jpayne@68:         index = (index + 1) % len(words)
jpayne@68:         if index == 0:
jpayne@68:             self.bell()            # Warn we cycled around
jpayne@68:         self.text.insert("insert", newword)
jpayne@68:         curinsert = self.text.index("insert")
jpayne@68:         curline = self.text.get("insert linestart", "insert lineend")
jpayne@68:         self.state = words, index, curinsert, curline
jpayne@68:         return "break"
jpayne@68: 
jpayne@68:     def getwords(self):
jpayne@68:         "Return a list of words that match the prefix before the cursor."
jpayne@68:         word = self.getprevword()
jpayne@68:         if not word:
jpayne@68:             return []
jpayne@68:         before = self.text.get("1.0", "insert wordstart")
jpayne@68:         wbefore = re.findall(r"\b" + word + r"\w+\b", before)
jpayne@68:         del before
jpayne@68:         after = self.text.get("insert wordend", "end")
jpayne@68:         wafter = re.findall(r"\b" + word + r"\w+\b", after)
jpayne@68:         del after
jpayne@68:         if not wbefore and not wafter:
jpayne@68:             return []
jpayne@68:         words = []
jpayne@68:         dict = {}
jpayne@68:         # search backwards through words before
jpayne@68:         wbefore.reverse()
jpayne@68:         for w in wbefore:
jpayne@68:             if dict.get(w):
jpayne@68:                 continue
jpayne@68:             words.append(w)
jpayne@68:             dict[w] = w
jpayne@68:         # search onwards through words after
jpayne@68:         for w in wafter:
jpayne@68:             if dict.get(w):
jpayne@68:                 continue
jpayne@68:             words.append(w)
jpayne@68:             dict[w] = w
jpayne@68:         words.append(word)
jpayne@68:         return words
jpayne@68: 
jpayne@68:     def getprevword(self):
jpayne@68:         "Return the word prefix before the cursor."
jpayne@68:         line = self.text.get("insert linestart", "insert")
jpayne@68:         i = len(line)
jpayne@68:         while i > 0 and line[i-1] in self.wordchars:
jpayne@68:             i = i-1
jpayne@68:         return line[i:]
jpayne@68: 
jpayne@68: 
jpayne@68: if __name__ == '__main__':
jpayne@68:     from unittest import main
jpayne@68:     main('idlelib.idle_test.test_autoexpand', verbosity=2)