Initial revision

Lib/idlelib/CallTips.py

@@ -0,0 +1,190 @@
+# CallTips.py - An IDLE extension that provides "Call Tips" - ie, a floating window that
+# displays parameter information as you open parens.
+
+import string
+import sys
+import types
+
+class CallTips:
+
+    menudefs = [
+    ]
+
+    keydefs = {
+        '<<paren-open>>': ['<Key-parenleft>'],
+        '<<paren-close>>': ['<Key-parenright>'],
+        '<<check-calltip-cancel>>': ['<KeyRelease>'],
+        '<<calltip-cancel>>': ['<ButtonPress>', '<Key-Escape>'],
+    }
+
+    windows_keydefs = {
+    }
+
+    unix_keydefs = {
+    }
+
+    def __init__(self, editwin):
+        self.editwin = editwin
+        self.text = editwin.text
+        self.calltip = None
+        if hasattr(self.text, "make_calltip_window"):
+            self._make_calltip_window = self.text.make_calltip_window
+        else:
+            self._make_calltip_window = self._make_tk_calltip_window
+
+    def close(self):
+        self._make_calltip_window = None
+
+    # Makes a Tk based calltip window.  Used by IDLE, but not Pythonwin.
+    # See __init__ above for how this is used.
+    def _make_tk_calltip_window(self):
+        import CallTipWindow
+        return CallTipWindow.CallTip(self.text)
+
+    def _remove_calltip_window(self):
+        if self.calltip:
+            self.calltip.hidetip()
+            self.calltip = None
+        
+    def paren_open_event(self, event):
+        self._remove_calltip_window()
+        arg_text = get_arg_text(self.get_object_at_cursor())
+        if arg_text:
+            self.calltip_start = self.text.index("insert")
+            self.calltip = self._make_calltip_window()
+            self.calltip.showtip(arg_text)
+        return "" #so the event is handled normally.
+
+    def paren_close_event(self, event):
+        # Now just hides, but later we should check if other
+        # paren'd expressions remain open.
+        self._remove_calltip_window()
+        return "" #so the event is handled normally.
+
+    def check_calltip_cancel_event(self, event):
+        if self.calltip:
+            # If we have moved before the start of the calltip,
+            # or off the calltip line, then cancel the tip.
+            # (Later need to be smarter about multi-line, etc)
+            if self.text.compare("insert", "<=", self.calltip_start) or \
+               self.text.compare("insert", ">", self.calltip_start + " lineend"):
+                self._remove_calltip_window()
+        return "" #so the event is handled normally.
+
+    def calltip_cancel_event(self, event):
+        self._remove_calltip_window()
+        return "" #so the event is handled normally.
+
+    def get_object_at_cursor(self,
+                             wordchars="._" + string.uppercase + string.lowercase + string.digits):
+        # XXX - This needs to be moved to a better place
+        # so the "." attribute lookup code can also use it.
+        text = self.text
+        chars = text.get("insert linestart", "insert")
+        i = len(chars)
+        while i and chars[i-1] in wordchars:
+            i = i-1
+        word = chars[i:]
+        if word:
+            # How is this for a hack!
+            import sys, __main__
+            namespace = sys.modules.copy()
+            namespace.update(__main__.__dict__)
+            try:
+                    return eval(word, namespace)
+            except:
+                    pass
+        return None # Can't find an object.
+
+def _find_constructor(class_ob):
+    # Given a class object, return a function object used for the
+    # constructor (ie, __init__() ) or None if we can't find one.
+    try:
+        return class_ob.__init__.im_func
+    except AttributeError:
+        for base in class_ob.__bases__:
+            rc = _find_constructor(base)
+            if rc is not None: return rc
+    return None
+
+def get_arg_text(ob):
+    # Get a string describing the arguments for the given object.
+    argText = ""
+    if ob is not None:
+        argOffset = 0
+        if type(ob)==types.ClassType:
+            # Look for the highest __init__ in the class chain.
+            fob = _find_constructor(ob)
+            if fob is None:
+                fob = lambda: None
+            else:
+                argOffset = 1
+        elif type(ob)==types.MethodType:
+            # bit of a hack for methods - turn it into a function
+            # but we drop the "self" param.
+            fob = ob.im_func
+            argOffset = 1
+        else:
+            fob = ob
+        # Try and build one for Python defined functions
+        if type(fob) in [types.FunctionType, types.LambdaType]:
+            try:
+                realArgs = fob.func_code.co_varnames[argOffset:fob.func_code.co_argcount]
+                defaults = fob.func_defaults or []
+                defaults = list(map(lambda name: "=%s" % name, defaults))
+                defaults = [""] * (len(realArgs)-len(defaults)) + defaults
+                items = map(lambda arg, dflt: arg+dflt, realArgs, defaults)
+                if fob.func_code.co_flags & 0x4:
+                    items.append("...")
+                if fob.func_code.co_flags & 0x8:
+                    items.append("***")
+                argText = string.join(items , ", ")
+                argText = "(%s)" % argText
+            except:
+                pass
+        # See if we can use the docstring
+        if hasattr(ob, "__doc__") and ob.__doc__:
+            pos = string.find(ob.__doc__, "\n")
+            if pos<0 or pos>70: pos=70
+            if argText: argText = argText + "\n"
+            argText = argText + ob.__doc__[:pos]
+
+    return argText
+
+#################################################
+#
+# Test code
+#
+if __name__=='__main__':
+
+    def t1(): "()"
+    def t2(a, b=None): "(a, b=None)"
+    def t3(a, *args): "(a, ...)"
+    def t4(*args): "(...)"
+    def t5(a, *args): "(a, ...)"
+    def t6(a, b=None, *args, **kw): "(a, b=None, ..., ***)"
+
+    class TC:
+        "(a=None, ...)"
+        def __init__(self, a=None, *b): "(a=None, ...)"
+        def t1(self): "()"
+        def t2(self, a, b=None): "(a, b=None)"
+        def t3(self, a, *args): "(a, ...)"
+        def t4(self, *args): "(...)"
+        def t5(self, a, *args): "(a, ...)"
+        def t6(self, a, b=None, *args, **kw): "(a, b=None, ..., ***)"
+
+    def test( tests ):
+        failed=[]
+        for t in tests:
+            expected = t.__doc__ + "\n" + t.__doc__
+            if get_arg_text(t) != expected:
+                failed.append(t)
+                print "%s - expected %s, but got %s" % (t, `expected`, `get_arg_text(t)`)
+        print "%d of %d tests failed" % (len(failed), len(tests))
+
+    tc = TC()
+    tests = t1, t2, t3, t4, t5, t6, \
+            TC, tc.t1, tc.t2, tc.t3, tc.t4, tc.t5, tc.t6
+
+    test(tests)