Regression: cabal-3.12.1.0 install ignores --program-suffix when checking whether exe is already installed

[andreasabel]

cabal-3.12.1.0 install wrongly ignores --program-suffix when checking whether exe is already installed:

$ cabal-3.12.1.0 install hello
...
Symlinking 'hello' to '/Users/test/.local/bin/hello'

$ cabal-3.12.1.0 install hello --program-suffix=-new
...
Error: [Cabal-7149]
Path '/Users/test/.local/bin/hello' already exists. Use --overwrite-policy=always to overwrite.

cabal-3.10.3.0 can still do this correctly:

$ cabal-3.10.3.0 install hello --program-suffix=-new
...
Symlinking 'hello' to '/Users/test/.local/bin/hello-new'

Regression possibly introduced by:

• Fix --program-suffix resulting in invalid symlink #10056 ATTN: @wismill
• 09c04e9 ATTN: philderbeast

The --program-suffix feature likely needs more systematic regression tests.

[ulysses4ever]

hey @wismill. As we're nearing 3.14.1.0 cabal-install, any chance you could take a look at this? It looks like in #10056 you modified the config flags inside the install action to "forget" about affixes in a big chunk of the action implementation. I suspect it should be limited...

[ulysses4ever]

I bisected it to 09c04e9, cc @philderbeast Sorry @wismill!

@philderbeast any chance you could look into this regression from your patch?

[wismill]

Sorry, I have no time at the moment to work on this. But the key is maybe from this comment:

Fixed by making the name of the executable in the store canonical, i.e.
always ignoring the program affix options.

I wonder it the following reported error:

Path '/Users/test/.local/bin/hello' already exists. Use --overwrite-policy=always to overwrite.

merely reports an overwrite that would happen in the store, not in ~/.local/bin.

It definitely needs a fix and a test for the use case of the current issue.

[philderbeast]

@philderbeast any chance you could look into this regression from your patch?

I've had a quick look but this looks too big for me to handle within my schedule for the next month.

The --program-suffix feature likely needs more systematic regression tests.

I could only find one test¹ for --program-suffix, a test that includes that option when checking "whether config options are commented or not".

$ grep -R 'program-suffix' ./**/*.hs
./cabal-install/src/Distribution/Client/ProjectConfig/Legacy.hs:        , "program-suffix"
./cabal-install/tests/IntegrationTests2.hs:  "-- program-suffix" @=? findLineWith True "program-suffix" defaultConfigFile
./Cabal/src/Distribution/Simple/Setup/Config.hs:          ["program-suffix"]

cabal/cabal-install/tests/IntegrationTests2.hs

Lines 1984 to 1985 in cc2c9d8

	-- Tests whether config options are commented or not
	testConfigOptionComments :: Assertion

cabal/cabal-install/tests/IntegrationTests2.hs

Line 2065 in cc2c9d8

"-- program-suffix" `assertHasCommentLine` "program-suffix"

Footnotes

1. I found more tests when checking files other than *.hs files. These seem to be lightweight configure and nix config tests. ↩