Support arbitrary waveform viewer

docs/cli.rst

@@ -166,9 +166,9 @@ VUnit automatically detects which simulators are available on the
 ``PATH`` environment variable and by default selects the first one
 found. For people who have multiple simulators installed the
 ``VUNIT_SIMULATOR`` environment variable can be set to one of
-``activehdl``, ``rivierapro``, ``ghdl`` or ``modelsim`` to specify
-which simulator to use. ``modelsim`` is used for both ModelSim and
-Questa as VUnit handles these simulators identically.
+``activehdl``, ``rivierapro``, ``ghdl``, ``nvc```, or ``modelsim`` to
+specify which simulator to use. ``modelsim`` is used for both ModelSim
+and Questa as VUnit handles these simulators identically.
 
 In addition to VUnit scanning the ``PATH`` the simulator executable
 path can be explicitly configured by setting a

docs/news.d/1002.feature.rst

@@ -0,0 +1,11 @@
+[GHDL/NVC] Arbitrary waveform viewers are now supported by passing the ``--viewer``
+command line argument. As a consequence, ``ghdl.gtkwave_script.gui`` and
+``nvc.gtkwave_script.gui`` are deprecated in favour of ``ghdl.viewer_script.gui``
+and ``nvc.viewer_script.gui``, respectively. The ``--gtkwave-args`` and
+``--gtkwave-fmt`` command line arguments are deprecated in favour of ``--viewer-args``
+and ``--viewer-fmt``, respectively. ``ghdl.viewer.gui`` and ``nvc.viewer.gui`` can
+be used to set the preferred viewer from the run-file. If no viewer is explicitly
+requested, ``gtkwave`` or ``surfer`` is used, in that order. This also means that
+VUnit now uses ``surfer`` if ``gtkwave`` is not installed.
+
+[NVC] It is possible to get VCD waveform files by passing ``--viewer-fmt=vcd``.

docs/py/opts.rst

@@ -201,9 +201,15 @@ The following simulation options are known.
    With ``--elaborate``, execute ``ghdl -e`` instead of ``ghdl --elab-run --no-run``.
    Must be a boolean.
 
-``ghdl.gtkwave_script.gui``
-   A user defined TCL-file that is sourced after the design has been loaded in the GUI.
+``ghdl.viewer.gui``
+   Name of waveform viewer to use. The command line argument ``--viewer`` will have
+   precedence if provided. If neither is provided, ``gtkwave`` or ``surfer`` will be
+   used.
+
+``ghdl.viewer_script.gui``
+   A user defined file that is sourced after the design has been loaded in the GUI.
    For example this can be used to configure the waveform viewer. Must be a string.
+
    There are currently limitations in the HEAD revision of GTKWave that prevent the
    user from sourcing a list of scripts directly. The following is the current work
    around to sourcing multiple user TCL-files:
@@ -225,3 +231,17 @@ The following simulation options are known.
 ``nvc.sim_flags``
    Extra simulation flags passed to ``nvc -r``.
    Must be a list of strings.
+
+``nvc.viewer.gui``
+   Name of waveform viewer to use. The command line argument ``--viewer`` will have
+   precedence if provided. If neither is provided, ``gtkwave`` or ``surfer`` will be
+   used.
+
+``nvc.viewer_script.gui``
+   A user defined file that is sourced after the design has been loaded in the GUI.
+   For example this can be used to configure the waveform viewer. Must be a string.
+
+   There are currently limitations in the HEAD revision of GTKWave that prevent the
+   user from sourcing a list of scripts directly. The following is the current work
+   around to sourcing multiple user TCL-files:
+   ``source <path/to/script.tcl>``

tests/unit/test_ghdl_interface.py

@@ -27,22 +27,6 @@ class TestGHDLInterface(unittest.TestCase):
     Test the GHDL interface
     """
 
-    @mock.patch("vunit.sim_if.ghdl.GHDLInterface.find_executable")
-    def test_runtime_error_on_missing_gtkwave(self, find_executable):
-        executables = {}
-
-        def find_executable_side_effect(name):
-            return executables[name]
-
-        find_executable.side_effect = find_executable_side_effect
-
-        executables["gtkwave"] = ["path"]
-        GHDLInterface(prefix="prefix", output_path="")
-
-        executables["gtkwave"] = []
-        GHDLInterface(prefix="prefix", output_path="")
-        self.assertRaises(RuntimeError, GHDLInterface, prefix="prefix", output_path="", gui=True)
-
     @mock.patch("subprocess.check_output", autospec=True)
     def test_parses_llvm_backend(self, check_output):
         version = b"""\

vunit/sim_if/_viewermixin.py

@@ -0,0 +1,60 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at http://mozilla.org/MPL/2.0/.
+#
+# Copyright (c) 2014-2024, Lars Asplund [email protected]
+"""
+Viewer handling for GHDL and NVC.
+"""
+
+
+class ViewerMixin:
+    """
+    Mixin class for handling common viewer functionality for the GHDL and NVC simulators.
+    """
+
+    __slots__ = (
+        "_gui",
+        "_viewer",
+        "_viewer_fmt",
+        "_viewer_args",
+        "_gtkwave_available",
+        "_surfer_available",
+    )
+
+    def __init__(self, gui, viewer, viewer_fmt, viewer_args):
+        self._gui = gui
+        self._viewer_fmt = viewer_fmt
+        self._viewer_args = viewer_args
+        self._viewer = viewer
+        if gui:
+            self._gtkwave_available = self.find_executable("gtkwave")
+            self._surfer_available = self.find_executable("surfer")
+
+    def _get_viewer(self, config):
+        """
+        Determine the waveform viewer to use.
+
+        Falls back to gtkwave or surfer, in that order, if none is provided.
+        """
+        viewer = self._viewer or config.sim_options.get(self.name + ".viewer.gui", None)
+
+        if viewer is None:
+            if self._gtkwave_available:
+                viewer = "gtkwave"
+            elif self._surfer_available:
+                viewer = "surfer"
+            else:
+                raise RuntimeError("No viewer found. GUI not possible. Install GTKWave or Surfer.")
+
+        elif not self.find_executable(viewer):
+            viewers = []
+            if self._gtkwave_available:
+                viewers += ["gtkwave"]
+            if self._surfer_available:
+                viewers += ["surfer"]
+            addendum = f" The following viewer(s) are found in the path: {', '.join(viewers)}" if viewers else ""
+            raise RuntimeError(
+                f"Cannot find the {viewer} executable in the PATH environment variable. GUI not possible.{addendum}"
+            )
+        return viewer

vunit/sim_if/ghdl.py

@@ -21,11 +21,12 @@
 from ..ostools import Process
 from . import SimulatorInterface, ListOfStringOption, StringOption, BooleanOption
 from ..vhdl_standard import VHDL
+from ._viewermixin import ViewerMixin
 
 LOGGER = logging.getLogger(__name__)
 
 
-class GHDLInterface(SimulatorInterface):  # pylint: disable=too-many-instance-attributes
+class GHDLInterface(SimulatorInterface, ViewerMixin):  # pylint: disable=too-many-instance-attributes
     """
     Interface for GHDL simulator
     """
@@ -43,7 +44,9 @@ class GHDLInterface(SimulatorInterface):  # pylint: disable=too-many-instance-at
     sim_options = [
         ListOfStringOption("ghdl.sim_flags"),
         ListOfStringOption("ghdl.elab_flags"),
-        StringOption("ghdl.gtkwave_script.gui"),
+        StringOption("ghdl.gtkwave_script.gui"),  # Deprecated in v5.1.0
+        StringOption("ghdl.viewer_script.gui"),
+        StringOption("ghdl.viewer.gui"),
         BooleanOption("ghdl.elab_e"),
     ]
 
@@ -52,14 +55,16 @@ def add_arguments(parser):
         """
         Add command line arguments
         """
-        group = parser.add_argument_group("ghdl", description="GHDL specific flags")
+        group = parser.add_argument_group("ghdl/nvc", description="GHDL/NVC specific flags")
         group.add_argument(
+            "--viewer-fmt",
             "--gtkwave-fmt",
             choices=["vcd", "fst", "ghw"],
             default=None,
-            help="Save .vcd, .fst, or .ghw to open in gtkwave",
+            help="Save .vcd, .fst, or .ghw to open in waveform viewer. NVC does not support ghw.",
         )
-        group.add_argument("--gtkwave-args", default="", help="Arguments to pass to gtkwave")
+        group.add_argument("--viewer-args", "--gtkwave-args", default="", help="Arguments to pass to waveform viewer")
+        group.add_argument("--viewer", default=None, help="Waveform viewer to use")
 
     @classmethod
     def from_args(cls, args, output_path, **kwargs):
@@ -71,8 +76,9 @@ def from_args(cls, args, output_path, **kwargs):
             output_path=output_path,
             prefix=prefix,
             gui=args.gui,
-            gtkwave_fmt=args.gtkwave_fmt,
-            gtkwave_args=args.gtkwave_args,
+            viewer_fmt=args.viewer_fmt,
+            viewer_args=args.viewer_args,
+            viewer=args.viewer,
             backend=cls.determine_backend(prefix),
         )
 
@@ -88,20 +94,23 @@ def __init__(  # pylint: disable=too-many-arguments
         output_path,
         prefix,
         gui=False,
-        gtkwave_fmt=None,
-        gtkwave_args="",
+        viewer_fmt=None,
+        viewer_args="",
+        viewer=None,
         backend="llvm",
     ):
         SimulatorInterface.__init__(self, output_path, gui)
+        ViewerMixin.__init__(
+            self,
+            gui=gui,
+            viewer=viewer,
+            viewer_fmt="ghw" if gui and viewer_fmt is None else viewer_fmt,
+            viewer_args=viewer_args,
+        )
+
         self._prefix = prefix
         self._project = None
 
-        if gui and (not self.find_executable("gtkwave")):
-            raise RuntimeError("Cannot find the gtkwave executable in the PATH environment variable. GUI not possible")
-
-        self._gui = gui
-        self._gtkwave_fmt = "ghw" if gui and gtkwave_fmt is None else gtkwave_fmt
-        self._gtkwave_args = gtkwave_args
         self._backend = backend
         self._vhdl_standard = None
         self._coverage_test_dirs = set()  # For gcov
@@ -123,7 +132,7 @@ def _get_version_output(cls, prefix):
     @classmethod
     def _get_help_output(cls, prefix):
         """
-        Get the output of 'ghdl --version'
+        Get the output of 'ghdl --help'
         """
         return subprocess.check_output([str(Path(prefix) / cls.executable), "--help"]).decode()
 
@@ -315,11 +324,11 @@ def _get_command(
             sim += ["--ieee-asserts=disable"]
 
         if wave_file:
-            if self._gtkwave_fmt == "ghw":
+            if self._viewer_fmt == "ghw":
                 sim += [f"--wave={wave_file!s}"]
-            elif self._gtkwave_fmt == "vcd":
+            elif self._viewer_fmt == "vcd":
                 sim += [f"--vcd={wave_file!s}"]
-            elif self._gtkwave_fmt == "fst":
+            elif self._viewer_fmt == "fst":
                 sim += [f"--fst={wave_file!s}"]
 
         if not ghdl_e:
@@ -355,8 +364,8 @@ def simulate(self, output_path, test_suite_name, config, elaborate_only):  # pyl
 
         ghdl_e = elaborate_only and config.sim_options.get("ghdl.elab_e", False)
 
-        if self._gtkwave_fmt is not None:
-            data_file_name = str(Path(script_path) / f"wave.{self._gtkwave_fmt!s}")
+        if self._viewer_fmt is not None:
+            data_file_name = str(Path(script_path) / f"wave.{self._viewer_fmt!s}")
             if Path(data_file_name).exists():
                 remove(data_file_name)
         else:
@@ -382,10 +391,17 @@ def simulate(self, output_path, test_suite_name, config, elaborate_only):  # pyl
         except Process.NonZeroExitCode:
             status = False
 
+        if config.sim_options.get(self.name + ".gtkwave_script.gui", None):
+            LOGGER.warning("%s.gtkwave_script.gui is deprecated and will be removed "
+                           "in a future version, use %s.viewer_script.gui instead",
+                           self.name, self.name)
+
         if self._gui and not elaborate_only:
-            cmd = ["gtkwave"] + shlex.split(self._gtkwave_args) + [data_file_name]
+            cmd = [self._get_viewer(config)] + shlex.split(self._viewer_args) + [data_file_name]
 
-            init_file = config.sim_options.get(self.name + ".gtkwave_script.gui", None)
+            init_file = config.sim_options.get(
+                self.name + ".viewer_script.gui", config.sim_options.get(self.name + ".gtkwave_script.gui", None)
+            )
             if init_file is not None:
                 cmd += ["--script", str(Path(init_file).resolve())]