CAM: add configuration value to suppress blank lines in refactored postprocessors

src/Mod/CAM/CAMTests/TestRefactoredTestPost.py

@@ -667,6 +667,42 @@ G54
 
     #############################################################################
 
+    def test00191(self):
+        """Make sure postprocessor doesn't crash on blank lines"""
+
+        path = [
+            Path.Command("G0 X1"),
+            Path.Command(""),
+            Path.Command("G0 X2"),
+        ]
+
+        self.post.values["OUTPUT_BLANK_LINES"] = True
+        self.multi_compare(
+            path,
+            """G90
+G21
+G54
+G0 X1.000
+
+G0 X2.000
+""",
+            "",
+        )
+
+        self.post.values["OUTPUT_BLANK_LINES"] = False
+        self.multi_compare(
+            path,
+            """G90
+G21
+G54
+G0 X1.000
+G0 X2.000
+""",
+            "",
+        )
+
+    #############################################################################
+
     def test00200(self):
         """Test Outputting visible arguments.
 

src/Mod/CAM/Path/Post/UtilsArguments.py

@@ -478,6 +478,10 @@ def init_shared_values(values: Values) -> None:
     #
     values["OUTPUT_COMMENTS"] = True
     #
+    # If True output blank lines.  If False blank lines are suppressed.
+    #
+    values["OUTPUT_BLANK_LINES"] = True
+    #
     # if False duplicate axis values or feeds are suppressed
     # if they are the same as the previous line.
     #

src/Mod/CAM/Path/Post/UtilsParse.py

@@ -719,6 +719,11 @@ def parse_a_path(values: Values, gcode: Gcode, pathobj) -> None:
         command = c.Name
         command_line = []
 
+        # Skip blank lines if requested
+        if not command:
+            if not values["OUTPUT_BLANK_LINES"]:
+                continue
+
         # Modify the command name if necessary
         if command.startswith("("):
             if not values["OUTPUT_COMMENTS"]: