opam update doesn’t need to checksum every extra-files

[kit-ty-kate]

While testing # using opam update -vvv I realised that opam update seems to check every extra-files from the repository it is updating:

$ opam update -vvv
[...]
+ /usr/bin/openssl "sha512" "/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.13.2/files/coqide.install"
- SHA512(/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.13.2/files/coqide.install)= 3eba9f94c7cc2a4b9b4fc8be549d7e5b3125315360cc85fb1001ba25d2eb5fb174c358ba3295036dda44197ec068e18c0b2f3b341aaa77b73fdb75d1e7d5c27f
+ /usr/bin/openssl "sha512" "/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.11.1/files/coqide.install"
- SHA512(/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.11.1/files/coqide.install)= 0c59f0c3cf3453e92c02b29aceb31090020410d2b0dd2856172cd19b1b2b58b2a1d46047fb08a9c1d4767d87934c73ae6adfcb4204b1ea6a55a85ba75b2b812d
+ /usr/bin/openssl "sha512" "/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.12.0/files/coqide.install"
- SHA512(/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.12.0/files/coqide.install)= 0c59f0c3cf3453e92c02b29aceb31090020410d2b0dd2856172cd19b1b2b58b2a1d46047fb08a9c1d4767d87934c73ae6adfcb4204b1ea6a55a85ba75b2b812d
+ /usr/bin/openssl "sha512" "/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.10.2/files/coqide.install"
- SHA512(/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.10.2/files/coqide.install)= 0c59f0c3cf3453e92c02b29aceb31090020410d2b0dd2856172cd19b1b2b58b2a1d46047fb08a9c1d4767d87934c73ae6adfcb4204b1ea6a55a85ba75b2b812d
+ /usr/bin/openssl "sha512" "/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.12.1/files/coqide.install"
- SHA512(/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.12.1/files/coqide.install)= 0c59f0c3cf3453e92c02b29aceb31090020410d2b0dd2856172cd19b1b2b58b2a1d46047fb08a9c1d4767d87934c73ae6adfcb4204b1ea6a55a85ba75b2b812d
+ /usr/bin/openssl "sha512" "/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.13.0/files/coqide.install"
- SHA512(/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.13.0/files/coqide.install)= 3eba9f94c7cc2a4b9b4fc8be549d7e5b3125315360cc85fb1001ba25d2eb5fb174c358ba3295036dda44197ec068e18c0b2f3b341aaa77b73fdb75d1e7d5c27f
+ /usr/bin/openssl "sha512" "/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.13.1/files/coqide.install"
- SHA512(/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.13.1/files/coqide.install)= 3eba9f94c7cc2a4b9b4fc8be549d7e5b3125315360cc85fb1001ba25d2eb5fb174c358ba3295036dda44197ec068e18c0b2f3b341aaa77b73fdb75d1e7d5c27f
+ /usr/bin/openssl "sha512" "/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.11.2/files/coqide.install"
- SHA512(/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.11.2/files/coqide.install)= 0c59f0c3cf3453e92c02b29aceb31090020410d2b0dd2856172cd19b1b2b58b2a1d46047fb08a9c1d4767d87934c73ae6adfcb4204b1ea6a55a85ba75b2b812d
+ /usr/bin/openssl "sha512" "/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.10.0/files/fix-parallel-make.patch"
- SHA512(/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.10.0/files/fix-parallel-make.patch)= 3801156db1d95bf35948599f366775afff72bbeef958e73321b1f9627220ef7ca61b402c478374f31a23db0f4394bafca5fa56c0708dfad589cad85bfa20d526
+ /usr/bin/openssl "sha512" "/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.10.0/files/coqide.install"
- SHA512(/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.10.0/files/coqide.install)= 0c59f0c3cf3453e92c02b29aceb31090020410d2b0dd2856172cd19b1b2b58b2a1d46047fb08a9c1d4767d87934c73ae6adfcb4204b1ea6a55a85ba75b2b812d
+ /usr/bin/openssl "sha512" "/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.10.1/files/coqide.install"
- SHA512(/Users/kit_ty_kate/.opam/repo/default/packages/coqide/coqide.8.10.1/files/coqide.install)= 0c59f0c3cf3453e92c02b29aceb31090020410d2b0dd2856172cd19b1b2b58b2a1d46047fb08a9c1d4767d87934c73ae6adfcb4204b1ea6a55a85ba75b2b812d
[...]

I’m not sure why this is the case. extra-files are checked when installing anyway so why check at update time. It takes some time to do for files using SHA* instead of MD5 and does not seem to serve any purpose

[dra27]

Briefly discussed today: the check is there for Conex. It's possibly wasteful that we check the sha512s of files which are the same as we already have - worth getting some numbers to see?