Use os.pathsep instead of hand-rolled equivalent

The ZIP installer now contains a `libs/bin` folder that contains
`ifcmerge`. Bonsai on `register()` adds this folder to the system `PATH`
for the current Blender session. Advantage of this is that we don't have
to fiddle with the registry on windows, or install files to
`~/.local/bin` on Linux, it _should_ work on Darwin, updates are
automatic, and we have a mechanism to ship other executables if
required.

(Note that ifcmerge.exe increases the size of the Windows Bonsai ZIP
download by about 7MB)

If Git isn't installed on Windows, the Git panel now offers to install
it from the Windows Package Manager Community Repository using `winget`.

src/bonsai/Makefile

@@ -229,6 +229,17 @@ endif
 	# Required for Desktop icon and file association
 	cp -r bonsai/libs/desktop build/bonsai/libs/
 
+	# folder for executable files
+	mkdir -p build/bonsai/libs/bin
+
+	# required for three-way git merging
+ifeq ($(PLATFORM), win)
+	cd build/bonsai/libs/bin && wget https://github.com/brunopostle/ifcmerge/releases/download/2024-06-24/ifcmerge.zip
+	cd build/bonsai/libs/bin && unzip ifcmerge.zip && rm ifcmerge.zip
+else
+	cd build/bonsai/libs/bin && wget https://raw.githubusercontent.com/brunopostle/ifcmerge/main/ifcmerge && chmod +x ifcmerge
+endif
+
 	# Generate translations module for Bonsai build
 	git clone https://github.com/IfcOpenShell/bonsai-translations.git build/working
 	$(PYTHON) scripts/bonsai_translations.py -i "build/working" -o "build/bonsai"

src/bonsai/bonsai/bim/__init__.py

@@ -258,6 +258,10 @@ def register():
     icons = icon_preview
     bpy.app.translations.register("bonsai", translations_dict)
 
+    import bonsai.tool as tool
+
+    tool.Blender.ensure_bin_in_path()
+
 
 def unregister():
     global icons

src/bonsai/bonsai/bim/module/ifcgit/__init__.py

@@ -37,6 +37,7 @@ classes = (
     operator.Push,
     operator.RefreshGit,
     operator.SwitchRevision,
+    operator.InstallGit,
     prop.IfcGitTag,
     prop.IfcGitListItem,
     prop.IfcGitProperties,

src/bonsai/bonsai/bim/module/ifcgit/operator.py

@@ -386,3 +386,25 @@ class ObjectLog(bpy.types.Operator):
         step_id = context.active_object.BIMObjectProperties.ifc_definition_id
         core.entity_log(tool.IfcGit, tool.Ifc, step_id, self)
         return {"FINISHED"}
+
+
+class InstallGit(bpy.types.Operator):
+    """Install Git Version Control System from the
+    Windows Package Manager Community Repository,
+    requires restarting Blender after installation"""
+
+    bl_label = "Install Git"
+    bl_idname = "ifcgit.install_git"
+    bl_options = {"REGISTER"}
+
+    @classmethod
+    def poll(cls, context):
+        IfcGitData.make_sure_is_loaded()
+        if IfcGitData.data["git_exe"]:
+            return False
+        return True
+
+    def execute(self, context):
+        core.install_git(tool.IfcGit, self)
+        refresh()
+        return {"FINISHED"}

src/bonsai/bonsai/bim/module/ifcgit/ui.py

@@ -1,6 +1,7 @@
 import bpy
 import time
 import os
+import platform
 
 from bonsai.bim.module.ifcgit.data import IfcGitData
 
@@ -26,6 +27,12 @@ class IFCGIT_PT_panel(bpy.types.Panel):
         if not IfcGitData.data["git_exe"]:
             row = layout.row()
             row.label(text="Git is not installed", icon="ERROR")
+            if platform.system() == "Windows":
+                row.operator(
+                    "ifcgit.install_git",
+                    text="Install Git",
+                    icon="PACKAGE",
+                )
             return
 
         props = context.scene.IfcGitProperties

src/bonsai/bonsai/core/ifcgit.py

@@ -17,6 +17,7 @@
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
 from __future__ import annotations
+import platform
 from typing import TYPE_CHECKING, Optional
 
 if TYPE_CHECKING:
@@ -130,3 +131,10 @@ def entity_log(ifcgit: tool.IfcGit, ifc: tool.Ifc, step_id: int, operator: bpy.t
     log_text = ifcgit.entity_log(path_ifc, step_id)
     # ERROR is only way to display a multi-line message
     operator.report({"ERROR"}, log_text)
+
+
+def install_git(ifcgit: tool.IfcGit, operator: bpy.types.Operator) -> None:
+    if platform.system() == "Windows":
+        ifcgit.install_git_windows(operator=operator)
+    else:
+        print("install_git() not implemented")

src/bonsai/bonsai/tool/blender.py

@@ -430,6 +430,14 @@ class Blender(bonsai.core.tool.Blender):
             return blender_path
         return bpy.path.abspath("//") / blender_path
 
+    @classmethod
+    def ensure_bin_in_path(cls) -> None:
+        """Check 'bin' folder is in PATH, if not add for this session"""
+        bin_dir = str(Path(__file__).parent.parent.resolve() / "libs" / "bin")
+        current_path = os.environ["PATH"]
+        if bin_dir not in current_path:
+            os.environ["PATH"] = current_path + os.pathsep + bin_dir
+
     @classmethod
     def get_default_selection_keypmap(cls) -> tuple:
         """keymap to replicate default blender selection behaviour with click and box selection"""

src/bonsai/bonsai/tool/ifcgit.py

@@ -19,6 +19,7 @@
 from __future__ import annotations
 import os
 import re
+import subprocess
 import bpy
 import logging
 from bonsai.bim import import_ifc
@@ -546,6 +547,17 @@ class IfcGit:
             logtext = "No Git history found :("
         return logtext
 
+    @classmethod
+    def install_git_windows(cls, operator: bpy.types.Operator) -> None:
+        """Command to install Git on Windows using winget"""
+        command = ["winget", "install", "--id", "Git.Git", "-e", "--source", "winget"]
+        try:
+            subprocess.run(command, check=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        except subprocess.CalledProcessError as e:
+            operator.report({"ERROR"}, f"Called Process Error occurred: {e}")
+        except FileNotFoundError:
+            operator.report({"ERROR"}, "Winget is not available. Make sure Windows Package Manager is installed.")
+
 
 class IfcGitRepo:
     repo: git.Repo = None