better handle different types of failure with block imports, in parti…

…cular compile time errors, better diagnostics

bdsim/run_sim.py

@@ -2,6 +2,7 @@
 from pathlib import Path
 import sys
 import importlib
+import traceback as tb
 import inspect
 from collections import Counter, namedtuple
 import argparse
@@ -212,7 +213,6 @@ def blockname(name):
 
 
 class BDSimState:
-
     """
     :ivar x: state vector
     :vartype x: np.ndarray
@@ -1168,7 +1168,11 @@ def indent(s):
         block = namedtuple("block", "name, cls, path")
 
         if toolboxes:
-            packages = ["bdsim", "roboticstoolbox", "machinevisiontoolbox"]
+            packages = [
+                "bdsim",
+                "roboticstoolbox",
+                "machinevisiontoolbox",
+            ]
         else:
             packages = ["bdsim"]
         env = os.getenv("BDSIMPATH")
@@ -1182,20 +1186,32 @@ def indent(s):
         for package in packages:
             try:
                 spec = importlib.util.find_spec(".blocks", package=package)
-                if spec is None:
-                    print(f"package {package} has no blocks module")
-                    continue
-                pkg = spec.loader.load_module()
-            except ModuleNotFoundError:
-                print(f"package {package} not found")
+            except ModuleNotFoundError as err:
+                print(
+                    f"package {package} not loaded: not found, not a proper package, no blocks module"
+                )
                 continue
-            except ImportError:
-                print(f"package {package} load error, continuing")
-                import textwrap
 
-                print(textwrap.indent(traceback.format_exc(), "    "))
+            if spec is None:
+                print(f"package {package} not found or has no blocks module")
                 continue
 
+            try:
+                pkg = spec.loader.load_module()
+            except Exception as err:
+                print(f"package {package} contains a compile error")
+                exc = sys.exception()
+                print(fg("red"))
+                tb.print_exception(exc, limit=-4)
+                print(attr(0))
+                continue
+            # except ImportError:
+            #     print(f"package {package} load error, continuing")
+            #     import textwrap
+
+            #     print(textwrap.indent(traceback.format_exc(), "    "))
+            #     continue
+
             moduledict = {}
 
             for name, value in pkg.__dict__.items():
@@ -1246,9 +1262,9 @@ def indent(s):
 
                 # create a dict for the block with metadata
                 block_info = {}
-                block_info[
-                    "path"
-                ] = pkg.__path__  # path to folder holding block definition
+                block_info["path"] = (
+                    pkg.__path__
+                )  # path to folder holding block definition
                 block_info["classname"] = name
                 block_info["blockname"] = blockname(name)