Adding upstream version 3.0.36.upstream/3.0.36upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 84 insertions, 0 deletions

diff --git a/examples/prompts/inputhook.py b/examples/prompts/inputhook.py
new file mode 100755
index 0000000..8520790
--- /dev/null
+++ b/examples/prompts/inputhook.py
@@ -0,0 +1,84 @@
+#!/usr/bin/env python
+"""
+An example that demonstrates how inputhooks can be used in prompt-toolkit.
+
+An inputhook is a callback that an eventloop calls when it's idle. For
+instance, readline calls `PyOS_InputHook`. This allows us to do other work in
+the same thread, while waiting for input. Important however is that we give the
+control back to prompt-toolkit when some input is ready to be processed.
+
+There are two ways to know when input is ready. One way is to poll
+`InputHookContext.input_is_ready()`. Another way is to check for
+`InputHookContext.fileno()` to be ready. In this example we do the latter.
+"""
+import gobject
+import gtk
+from pygments.lexers.python import PythonLexer
+
+from prompt_toolkit.eventloop.defaults import create_event_loop
+from prompt_toolkit.lexers import PygmentsLexer
+from prompt_toolkit.patch_stdout import patch_stdout
+from prompt_toolkit.shortcuts import PromptSession
+
+
+def hello_world_window():
+    """
+    Create a GTK window with one 'Hello world' button.
+    """
+    # Create a new window.
+    window = gtk.Window(gtk.WINDOW_TOPLEVEL)
+    window.set_border_width(50)
+
+    # Create a new button with the label "Hello World".
+    button = gtk.Button("Hello World")
+    window.add(button)
+
+    # Clicking the button prints some text.
+    def clicked(data):
+        print("Button clicked!")
+
+    button.connect("clicked", clicked)
+
+    # Display the window.
+    button.show()
+    window.show()
+
+
+def inputhook(context):
+    """
+    When the eventloop of prompt-toolkit is idle, call this inputhook.
+
+    This will run the GTK main loop until the file descriptor
+    `context.fileno()` becomes ready.
+
+    :param context: An `InputHookContext` instance.
+    """
+
+    def _main_quit(*a, **kw):
+        gtk.main_quit()
+        return False
+
+    gobject.io_add_watch(context.fileno(), gobject.IO_IN, _main_quit)
+    gtk.main()
+
+
+def main():
+    # Create user interface.
+    hello_world_window()
+
+    # Enable threading in GTK. (Otherwise, GTK will keep the GIL.)
+    gtk.gdk.threads_init()
+
+    # Read input from the command line, using an event loop with this hook.
+    # We use `patch_stdout`, because clicking the button will print something;
+    # and that should print nicely 'above' the input line.
+    with patch_stdout():
+        session = PromptSession(
+            "Python >>> ", inputhook=inputhook, lexer=PygmentsLexer(PythonLexer)
+        )
+        result = session.prompt()
+    print("You said: %s" % result)
+
+
+if __name__ == "__main__":
+    main()