Make to-array.py list itself as a dependency of its outputs

This causes these dependencies to be rebuilt if the script chanages, which is heaps better than having to remember to clean the build directory every time.

meson.build

@@ -22,7 +22,8 @@ fs = import('fs')
 to_array = generator(
 	python3_prog,
 	output: [ '@PLAINNAME@.cpp', '@PLAINNAME@.h' ],
-	arguments: [ join_paths(meson.current_source_dir(), 'resources/to-array.py'), '@OUTPUT0@', '@OUTPUT1@', '@INPUT@', '@EXTRA_ARGS@' ]
+	depfile: '@PLAINNAME@.dep',
+	arguments: [ join_paths(meson.current_source_dir(), 'resources/to-array.py'), '@OUTPUT0@', '@OUTPUT1@', '@DEPFILE@', '@INPUT@', '@EXTRA_ARGS@' ]
 )
 
 render_icons_with_inkscape = get_option('render_icons_with_inkscape')

resources/to-array.py

@@ -1,13 +1,17 @@
+import os
 import sys
 
 (
 	script,
 	output_cpp_path,
 	output_h_path,
+	output_dep_path,
 	input_path,
 	symbol_name,
 ) = sys.argv
 
+script_path = os.path.realpath(__file__)
+
 with open(input_path, 'rb') as input_f:
 	data = input_f.read()
 data_size = len(data)
@@ -26,3 +30,16 @@ with open(output_h_path, 'w') as output_h_f:
 extern const unsigned char {symbol_name}[];
 extern const unsigned int {symbol_name}_size;
 ''')
+
+def dep_escape(s):
+	t = ''
+	for c in s:
+		if c in [ ' ', '\n', '\\', ':', '$' ]:
+			t += '$'
+		t += c
+	return t
+
+with open(output_dep_path, 'w') as output_dep_f:
+	output_dep_f.write(f'''
+{dep_escape(output_cpp_path)} {dep_escape(output_h_path)}: {dep_escape(input_path)} {dep_escape(script_path)}
+''')