29 lines
762 B
Python
29 lines
762 B
Python
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"""
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A script that replaces an old file with a new one, only if the contents
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actually changed. If not, the new file is simply deleted.
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This avoids wholesale rebuilds when a code (re)generation phase does not
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actually change the in-tree generated code.
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"""
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import os
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import sys
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def main(old_path, new_path):
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with open(old_path, 'rb') as f:
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old_contents = f.read()
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with open(new_path, 'rb') as f:
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new_contents = f.read()
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if old_contents != new_contents:
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os.replace(new_path, old_path)
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else:
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os.unlink(new_path)
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if __name__ == '__main__':
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if len(sys.argv) != 3:
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print("Usage: %s <path to be updated> <path with new contents>" % (sys.argv[0],))
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sys.exit(1)
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main(sys.argv[1], sys.argv[2])
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