fix(Cabal): Fix parsing of boolean values to debug-info

[zlonast]

fix: #12140

debug-info: False ​​are treated as NoDebugInfo, and debug-info: True ​​are treated as NormalDebugInfo

---

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[philderbeast]

This is very similar to intToOptimisationLevel. Maybe we could use a safeIntToEnum or intToEnum function to reduce the duplication?

safeIntToEnum :: (Enum a, Bounded a) => Int -> Maybe a
intToEnum :: (Enum a, Bounded a) => Int -> a

[zlonast]

There are no such functions, I took what I found in safe

intToEnum :: (Show a, Enum a, Bounded a) => String -> Int -> a
intToEnum str i =
  let res = toEnum i
      maxLevel = maxBound `asTypeOf` res
      minLevel = minBound `asTypeOf` res
   in if i >= fromEnum minLevel && i <= fromEnum maxLevel
        then res
        else
          error $
            "Bad "
              ++ str
              ++ ": "
              ++ show i
              ++ ". Valid values are "
              ++ show minLevel
              ++ ".."
              ++ show maxLevel

[philderbeast]

There are no such functions

I should have been clearer. I was only suggesting to possibly write helper functions with those signatures. Not even sure if that is possible.

[philderbeast]

There are odd zero-width characters in this file:

$ cat -A changelog.d/12202.md
---$
synopsis: Fix parsing of boolean values M-bM-^@M-^KM-bM-^@M-^Kto debug-info$
packages: [Cabal]$
prs: 12202$
issues: 12140$
---$
$
`False` values M-bM-^@M-^KM-bM-^@M-^Kare treated as `NoDebugInfo`, and `True` values M-bM-^@M-^KM-bM-^@M-^Kare treated as `NormalDebugInfo`.

[zlonast]

I'm not sure how this happened

[philderbeast]

If we're parsing booleans for debug-info in the project, would that also apply to the command line? If not, is error the best message?

$ cabal build --help
...
--enable-debug-info[=n]        Emit debug info (n is 0--3, default is 0)
--disable-debug-info           Don't emit debug info

$ cabal run cabal-install:exe:cabal -- build all --dry-run \
   --enable-debug-info=True
...
Can't parse debug info level True

HasCallStack backtrace:
  error, called at src/Distribution/Simple/Compiler.hs:383:8 in
  Cabal-3.19.0.0-inplace:Distribution.Simple.Compiler

$ cabal-3.18.1.0 build all --dry-run --enable-debug-info=True
Can't parse debug info level True
CallStack (from HasCallStack):
  error, called at src/Distribution/Simple/Compiler.hs:392:8 in
  Cabal-3.18.1.0-inplace:Distribution.Simple.Compiler

[zlonast]

@philderbeast Thanks for such a detailed review, yes, I think this approach should be applied to the command line as well.