bpython · etiennerichart · Jul 9, 2020 · Jul 14, 2020 · Jul 22, 2020 · Jul 28, 2020
diff --git a/bpython/autocomplete.py b/bpython/autocomplete.py
@@ -240,6 +240,9 @@ def locate(self, current_offset, line):
     def format(self, word):
         return after_last_dot(word)
 
+    def try_to_import(self, module_name):
+        return importcompletion.try_to_import(module_name)
+
 
 class FilenameCompletion(BaseCompletionType):
     def __init__(self, mode=SIMPLE):

diff --git a/bpython/curtsies.py b/bpython/curtsies.py
@@ -54,6 +54,9 @@ def __init__(self, config, locals_, banner, interp=None):
         self.request_undo = self.input_generator.event_trigger(
             bpythonevents.UndoEvent
         )
+        self.background_import_event = self.input_generator.event_trigger(
+            bpythonevents.BackgroundImportEvent
+        )
 
         with self.input_generator:
             pass  # temp hack to get .original_stty

diff --git a/bpython/curtsiesfrontend/events.py b/bpython/curtsiesfrontend/events.py
@@ -45,3 +45,10 @@ class UndoEvent(curtsies.events.Event):
 
     def __init__(self, n=1):
         self.n = n
+
+
+class BackgroundImportEvent(curtsies.events.Event):
+    """Background import for advanced auto complete."""
+
+    def __init__(self, module_name):
+        self.module_name = module_name
diff --git a/bpython/curtsiesfrontend/repl.py b/bpython/curtsiesfrontend/repl.py
@@ -37,6 +37,7 @@
 from bpython import autocomplete
 from bpython.translations import _
 from bpython.pager import get_pager_command
+from bpython.line import from_import_tab
 
 from bpython.curtsiesfrontend import replpainter as paint
 from bpython.curtsiesfrontend import sitefix
@@ -690,6 +691,13 @@ def process_control_event(self, e):
                     % (time.strftime("%X"), " & ".join(e.files_modified))
                 )
 
+        elif isinstance(e, bpythonevents.BackgroundImportEvent):
+            # self.comleters[1] should match to autocomplete's ImportCompletion class
+            self.completers[1].try_to_import(e.module_name)
+            self.status_bar.pop_permanent_message(
+                "Imported module %s" % e.module_name
+            )
+
         else:
             raise ValueError("Don't know how to handle event type: %r" % e)
 
@@ -872,6 +880,7 @@ def on_tab(self, back=False):
         2) complete the current word with characters common to all completions
         3) select the first or last match
         4) select the next or previous match if already have a match
+        5) if line is `from <module> import` and tab then import module and attr
         """
 
         def only_whitespace_left_of_cursor():
@@ -888,6 +897,19 @@ def only_whitespace_left_of_cursor():
                 self.add_normal_character(" ")
             return
 
+        # 5. if line is `from a import` and tab then import module and attr
+        line = self.current_line.split()
+        module_name = ""
+        if "from" in line and "import" in line:
+            # returns <module> name if the line contains: "from <module> import"
+            module_name = from_import_tab(self.current_line)
+            if module_name:
+                if module_name not in sys.modules:
+                    self.status_bar.push_permanent_message(
+                        "Imported module %s" % module_name
+                    )
+                    self.background_import_event(module_name=module_name)
+
         # run complete() if we don't already have matches
         if len(self.matches_iter.matches) == 0:
             self.list_win_visible = self.complete(tab=True)

diff --git a/bpython/importcompletion.py b/bpython/importcompletion.py
@@ -31,6 +31,7 @@
 import fnmatch
 import os
 import sys
+import importlib
 import warnings
 import importlib.machinery
 
@@ -91,6 +92,19 @@ def module_attr_matches(name):
     return attr_matches(name, prefix="", only_modules=True)
 
 
+def try_to_import(module_name):
+    """Called by curtsiesfrontend repl on tab to import module
+    in background for better auto completion: attr completion"""
+    try:
+        module = __import__(module_name)
+        module_path = os.path.dirname(module.__file__)
+        for mod in find_modules(module_path):
+            modules.add("%s.%s" % (module_name, mod))
+        modules.add(module_name)
+    except ImportError:
+        pass
+
+
 def complete(cursor_offset, line):
     """Construct a full list of possibly completions for imports."""
     tokens = line.split()

diff --git a/bpython/line.py b/bpython/line.py
@@ -117,6 +117,19 @@ def current_object_attribute(cursor_offset, line):
     return None
 
 
+from_import_tab_re = LazyReCompile(r"from ([\w0-9_.]*)\s+import")
+
+
+def from_import_tab(line):
+    matches = from_import_tab_re.finditer(line)
+    try:
+        module = next(matches)
+    except StopIteration:
+        pass
+    if module:
+        return str(module[1])
+
+
 current_from_import_from_re = LazyReCompile(
     r"from ([\w0-9_.]*)(?:\s+import\s+([\w0-9_]+[,]?\s*)+)*"
 )