build: Install to datadir

Install the python module to the data directory, not the python install
directory that meson gives us. Then, in the main script, try to find the
module and add it to the path by assuming the script is installed to
(prefix)/bin. Hopefully this will fix the ModuleNotFound errors.

blueprint-compiler.py

@@ -19,6 +19,13 @@
 #
 # SPDX-License-Identifier: LGPL-3.0-or-later
 
+import os, sys
+
+# Try to find the python module, assuming the current file is installed to (prefix)/bin
+dirname = os.path.join(os.path.dirname(os.path.dirname(__file__)), "share", "blueprint-compiler")
+if os.path.isdir(os.path.join(dirname, "blueprintcompiler")):
+    sys.path.insert(0, dirname)
+
 from blueprintcompiler import main
 
 if __name__ == "__main__":

meson.build

@@ -26,7 +26,7 @@ install_data(
 meson.override_find_program('blueprint-compiler', find_program('blueprint-compiler.py'))
 
 if not meson.is_subproject()
-  install_subdir('blueprintcompiler', install_dir: py.get_install_dir())
+  install_subdir('blueprintcompiler', install_dir: datadir / 'blueprint-compiler')
 endif
 
 subdir('tests')

tests/fuzz.py

@@ -1,5 +1,8 @@
+import os, sys
 from pythonfuzz.main import PythonFuzz
 
+sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))
+
 from blueprintcompiler import tokenizer, parser, decompiler
 from blueprintcompiler.completions import complete
 from blueprintcompiler.errors import PrintableError, MultipleErrors, CompileError, CompilerBugError