Description

The content of the file passed to standard input does not pass through unmodified and its content hash stored in metadata (note: I do not mean the metadata hash itself) is different than when the file name is given as an argument.

The problem is caused by our function for reading standard input, which replaces all newlines with \n and also adds a newline after the last line, even if originally there wasn't one.

In practice the consequences of this are probably minor because even if the source hashes end up being the same, metadata won't be - due to different file names (unless the file is called <stdin> which is unlikely). Still, I think that this behavior is unexpected by users and should be changed. It looks intentional though and might be a workaround for something so we should discuss it first.

Environment

• Compiler version: 0.8.5
• Operating system: Arch Linux

Steps to Reproduce

echo "contract C {}" > '<stdin>'
solc '<stdin>' --metadata

sources key from metadata output:

    "sources": {
        "<stdin>": {
            "keccak256": "0xbe86d3681a198587296ad6d4a834606197e1a8f8944922c501631b04e21eeba2",
            "urls": [
                "bzz-raw://7ef32f5b5f3b1ebe447f46969c01ce0e9190d0b90241cbc228255866326be8be",
                "dweb:/ipfs/QmZRepHCmeSSTfxZvKU5KS7pebBYT4khWhTnqh6GzBFU3M"
            ]
        }
    },

cat contract.sol | solc - --metadata

sources key from metadata output:

    "sources": {
        "<stdin>": {
            "keccak256": "0xec5627577fc5b8010229a1036827ef0739fb21bb05b7bf259947acdded145877",
            "urls": [
                "bzz-raw://2363616d36c4824b30b1698ffa5bc3443635a4d68eb4a93c7126b30b7716f0a1",
                "dweb:/ipfs/QmYENep2eioJEAMKZWozLW3fb2BHjNxCXSszbDzz2kfWJu"
            ]
        }
    },