Add return_on_result flag, to return immediately when a result is received

CHANGELOG.md

@@ -3,6 +3,8 @@
 ## <0.11.0.1>.dev0
 
 - *Replace this line with new entries*
+- Added a flag `return_on_result`, which causes an immediate return when a response of type 'result' is received,
+instead of waiting until the timeout passes.
 
 ## 0.11.0.0
 

MANIFEST.in

@@ -7,13 +7,13 @@ exclude example.py
 exclude .flake8
 exclude noxfile.py
 exclude mkdocs.yml
-exclude __pycache__
+global-exclude __pycache__
 exclude mypy.ini
 exclude *.in
 exclude *.txt
-exclude *.pyc
-exclude *.sw[po]
-exclude *~
+global-exclude *.pyc
+global-exclude *.sw[po]
+global-exclude *~
 
 prune tests
 prune docs

pygdbmi/IoManager.py

@@ -74,13 +74,17 @@ def get_gdb_response(
         self,
         timeout_sec: float = DEFAULT_GDB_TIMEOUT_SEC,
         raise_error_on_timeout: bool = True,
+        return_on_result: bool = False,
     ) -> List[Dict]:
         """Get response from GDB, and block while doing so. If GDB does not have any response ready to be read
         by timeout_sec, an exception is raised.
 
         Args:
             timeout_sec: Maximum time to wait for reponse. Must be >= 0. Will return after
             raise_error_on_timeout: Whether an exception should be raised if no response was found after timeout_sec
+            return_on_result: Whether to return when a response of type 'result' was received.
+                If return_on_result and raise_error_on_timeout, will raise an exception if no response of
+                type 'result' was received.
 
         Returns:
             List of parsed GDB responses, returned from gdbmiparser.parse_response, with the
@@ -96,19 +100,30 @@ def get_gdb_response(
             timeout_sec = 0
 
         if USING_WINDOWS:
-            retval = self._get_responses_windows(timeout_sec)
+            retval = self._get_responses_windows(timeout_sec, return_on_result)
         else:
-            retval = self._get_responses_unix(timeout_sec)
+            retval = self._get_responses_unix(timeout_sec, return_on_result)
 
         if not retval and raise_error_on_timeout:
             raise GdbTimeoutError(
                 "Did not get response from gdb after %s seconds" % timeout_sec
             )
 
-        else:
-            return retval
+        if (
+            return_on_result
+            and raise_error_on_timeout
+            and not any(response["type"] == "result" for response in retval)
+        ):
+            raise GdbTimeoutError(
+                "Did not get a 'result' response from gdb after %s seconds"
+                % timeout_sec
+            )
+
+        return retval
 
-    def _get_responses_windows(self, timeout_sec: float) -> List[Dict]:
+    def _get_responses_windows(
+        self, timeout_sec: float, return_on_result: bool
+    ) -> List[Dict]:
         """Get responses on windows. Assume no support for select and use a while loop."""
         timeout_time_sec = time.time() + timeout_sec
         responses = []
@@ -130,19 +145,29 @@ def _get_responses_windows(self, timeout_sec: float) -> List[Dict]:
                     pass
 
             responses += responses_list
+
+            if return_on_result and any(
+                response["type"] == "result" for response in (responses_list or [])
+            ):
+                break
+
             if timeout_sec == 0:
                 break
+
             elif responses_list and self._allow_overwrite_timeout_times:
                 timeout_time_sec = min(
                     time.time() + self.time_to_check_for_additional_output_sec,
                     timeout_time_sec,
                 )
+
             elif time.time() > timeout_time_sec:
                 break
 
         return responses
 
-    def _get_responses_unix(self, timeout_sec: float) -> List[Dict]:
+    def _get_responses_unix(
+        self, timeout_sec: float, return_on_result: bool
+    ) -> List[Dict]:
         """Get responses on unix-like system. Use select to wait for output."""
         timeout_time_sec = time.time() + timeout_sec
         responses = []
@@ -172,10 +197,19 @@ def _get_responses_unix(self, timeout_sec: float) -> List[Dict]:
                 responses_list = self._get_responses_list(raw_output, stream)
                 responses += responses_list
 
+            if return_on_result and any(
+                response["type"] == "result" for response in (responses_list or [])
+            ):
+                break
+
             if timeout_sec == 0:  # just exit immediately
                 break
 
-            elif responses_list and self._allow_overwrite_timeout_times:
+            elif (
+                responses_list
+                and self._allow_overwrite_timeout_times
+                and not return_on_result
+            ):
                 # update timeout time to potentially be closer to now to avoid lengthy wait times when nothing is being output by gdb
                 timeout_time_sec = min(
                     time.time() + self.time_to_check_for_additional_output_sec,
@@ -197,7 +231,10 @@ def _get_responses_list(
         """
         responses: List[Dict[Any, Any]] = []
 
-        (_new_output, self._incomplete_output[stream],) = _buffer_incomplete_responses(
+        (
+            _new_output,
+            self._incomplete_output[stream],
+        ) = _buffer_incomplete_responses(
             raw_output, self._incomplete_output.get(stream)
         )
 
@@ -227,6 +264,7 @@ def write(
         mi_cmd_to_write: Union[str, List[str]],
         timeout_sec: float = DEFAULT_GDB_TIMEOUT_SEC,
         raise_error_on_timeout: bool = True,
+        return_on_result: bool = False,
         read_response: bool = True,
     ) -> List[Dict]:
         """Write to gdb process. Block while parsing responses from gdb for a maximum of timeout_sec.
@@ -235,6 +273,9 @@ def write(
             mi_cmd_to_write: String to write to gdb. If list, it is joined by newlines.
             timeout_sec: Maximum number of seconds to wait for response before exiting. Must be >= 0.
             raise_error_on_timeout: If read_response is True, raise error if no response is received
+            return_on_result: Whether to return when a response of type 'result' was received.
+                If return_on_result and raise_error_on_timeout, will raise an exception if no response of
+                type 'result' was received.
             read_response: Block and read response. If there is a separate thread running, this can be false, and the reading thread read the output.
         Returns:
             List of parsed gdb responses if read_response is True, otherwise []
@@ -282,7 +323,9 @@ def write(
 
         if read_response is True:
             return self.get_gdb_response(
-                timeout_sec=timeout_sec, raise_error_on_timeout=raise_error_on_timeout
+                timeout_sec=timeout_sec,
+                raise_error_on_timeout=raise_error_on_timeout,
+                return_on_result=return_on_result,
             )
 
         else:

pygdbmi/gdbcontroller.py

@@ -110,20 +110,28 @@ def get_gdb_response(
         self,
         timeout_sec: float = DEFAULT_GDB_TIMEOUT_SEC,
         raise_error_on_timeout: bool = True,
+        return_on_result: bool = False,
     ) -> List[Dict]:
         """Get gdb response. See IoManager.get_gdb_response() for details"""
-        return self.io_manager.get_gdb_response(timeout_sec, raise_error_on_timeout)
+        return self.io_manager.get_gdb_response(
+            timeout_sec, raise_error_on_timeout, return_on_result
+        )
 
     def write(
         self,
         mi_cmd_to_write: Union[str, List[str]],
         timeout_sec: float = DEFAULT_GDB_TIMEOUT_SEC,
         raise_error_on_timeout: bool = True,
+        return_on_result: bool = False,
         read_response: bool = True,
     ) -> List[Dict]:
         """Write command to gdb. See IoManager.write() for details"""
         return self.io_manager.write(
-            mi_cmd_to_write, timeout_sec, raise_error_on_timeout, read_response
+            mi_cmd_to_write,
+            timeout_sec,
+            raise_error_on_timeout,
+            return_on_result,
+            read_response,
         )
 
     def exit(self) -> None:

tests/test_gdbcontroller.py

@@ -9,6 +9,7 @@
 import random
 import shutil
 import subprocess
+import time
 
 import pytest
 
@@ -68,6 +69,22 @@ def test_controller() -> None:
     assert response["stream"] == "stdout"
     assert response["token"] is None
 
+    # Verify exits quickly if return_on_result is True
+    t0 = time.monotonic()
+    responses = gdbmi.write(["-rubbish"], return_on_result=True)
+    t1 = time.monotonic()
+    duration = t1 - t0
+    assert len(responses) != 0
+    assert duration < 0.01
+
+    # Verify waits for timeout if return_on_result is not set
+    t0 = time.monotonic()
+    responses = gdbmi.write(["-rubbish"])
+    t1 = time.monotonic()
+    duration = t1 - t0
+    assert len(responses) != 0
+    assert duration >= 0.2
+
     responses = gdbmi.write(["-file-list-exec-source-files", "-break-insert main"])
     assert len(responses) != 0