Unverified Commit 39a4ab78 authored by Jacob Abel's avatar Jacob Abel
Browse files

lib/strings: Refactor toInt into toInt and toIntBase10

parent 3d196a5f

lib/default.nix

+1 −1
Original line number Diff line number Diff line
@@ -103,7 +103,7 @@ let 
      getName getVersion

      nameFromURL enableFeature enableFeatureAs withFeature

      withFeatureAs fixedWidthString fixedWidthNumber isStorePath

      toInt readPathsFromFile fileContents;

      toInt toIntBase10 readPathsFromFile fileContents;

    inherit (self.stringsWithDeps) textClosureList textClosureMap

      noDepEntry fullDepEntry packEntry stringAfter;

    inherit (self.customisation) overrideDerivation makeOverridable

lib/strings.nix

+51 −3
Original line number Diff line number Diff line
@@ -783,26 +783,74 @@ rec { 
    else

      false;



  /* Parse a string as an int.

  /* Parse a string as an int. Does not support parsing of integers with preceding zero due to

  ambiguity between zero-padded and octal numbers.



     Type: string -> int



     Example:



       toInt "1337"

       => 1337



       toInt "-4"

       => -4



       toInt " 123 "

       => 123



       toInt "00024"

       => 24

       => error: [json.exception.parse_error.101] parse error at line 1, column 2: syntax error

       while parsing value - unexpected number literal; expected end of input



       toInt "3.14"

       => error: floating point JSON numbers are not supported

  */

  # Obviously, it is a bit hacky to use fromJSON this way.

  toInt = str:

    let

      # RegEx: Match any leading whitespace, then any zero padding, and capture any remaining

      # RegEx: Match any leading whitespace, then any digits, and finally match any trailing

      # whitespace.

      strippedInput = match "[[:space:]]*([[:digit:]]+)[[:space:]]*" str;



      # RegEx: Match any leading whitespace, then a leading '0', then at least one digit following

      # after, and finally match any trailing whitespace.

      isLeadingZero = match "[[:space:]]*0[[:digit:]]+[[:space:]]*" str == [];



      # Attempt to parse input

      parsedInput = fromJSON (elemAt strippedInput 0);

    in

      if isLeadingZero

      then throw "Ambiguity in ${str} between octal and zero padded integer."

      else if strippedInput != null && isInt parsedInput

      then parsedInput

      else throw "Could not convert ${str} to int.";





  /* Parse a string as a base 10 int. This supports parsing of zero-padded integers.



     Type: string -> int



     Example:

       toIntBase10 "1337"

       => 1337



       toIntBase10 "-4"

       => -4



       toIntBase10 " 123 "

       => 123



       toIntBase10 "00024"

       => 24



       toIntBase10 "3.14"

       => error: floating point JSON numbers are not supported

  */

  # Obviously, it is a bit hacky to use fromJSON this way.

  toIntBase10 = str:

    let

      # RegEx: Match any leading whitespace, then match any zero padding, capture any remaining

      # digits after that, and finally match any trailing whitespace.

      strippedInput = match "[[:space:]]*0*([[:digit:]]+)[[:space:]]*" str;

lib/tests/misc.nix

+44 −16
Original line number Diff line number Diff line
@@ -339,20 +339,6 @@ runTests { 
    (0 == toInt " 0")

    (0 == toInt "0 ")

    (0 == toInt " 0 ")

    # Zero Padding

    (123 == toInt "0123")

    (123 == toInt "0000123")

    (0 == toInt "000000")

    # Whitespace and Zero Padding

    (123 == toInt " 0123")

    (123 == toInt "0123 ")

    (123 == toInt " 0123 ")

    (123 == toInt " 0000123")

    (123 == toInt "0000123 ")

    (123 == toInt " 0000123 ")

    (0 == toInt " 000000")

    (0 == toInt "000000 ")

    (0 == toInt " 000000 ")

  ];



  testToIntFails = testAllTrue [
@@ -360,10 +346,52 @@ runTests { 
    ( builtins.tryEval (toInt "123 123") == { success = false; value = false; } )

    ( builtins.tryEval (toInt "0 123") == { success = false; value = false; } )

    ( builtins.tryEval (toInt " 0d ") == { success = false; value = false; } )

    ( builtins.tryEval (toInt "00") == { success = false; value = false; } )

    ( builtins.tryEval (toInt "01") == { success = false; value = false; } )

    ( builtins.tryEval (toInt "002") == { success = false; value = false; } )

    ( builtins.tryEval (toInt " 002 ") == { success = false; value = false; } )

    ( builtins.tryEval (toInt " foo ") == { success = false; value = false; } )

    ( builtins.tryEval (toInt " foo 123 ") == { success = false; value = false; } )

    ( builtins.tryEval (toInt " foo 00123 ") == { success = false; value = false; } )

    ( builtins.tryEval (toInt " foo00123 ") == { success = false; value = false; } )

    ( builtins.tryEval (toInt " foo123 ") == { success = false; value = false; } )

  ];



  testToIntBase10 = testAllTrue [

    # Naive

    (123 == toIntBase10 "123")

    (0 == toIntBase10 "0")

    # Whitespace Padding

    (123 == toIntBase10 " 123")

    (123 == toIntBase10 "123 ")

    (123 == toIntBase10 " 123 ")

    (123 == toIntBase10 "   123   ")

    (0 == toIntBase10 " 0")

    (0 == toIntBase10 "0 ")

    (0 == toIntBase10 " 0 ")

    # Zero Padding

    (123 == toIntBase10 "0123")

    (123 == toIntBase10 "0000123")

    (0 == toIntBase10 "000000")

    # Whitespace and Zero Padding

    (123 == toIntBase10 " 0123")

    (123 == toIntBase10 "0123 ")

    (123 == toIntBase10 " 0123 ")

    (123 == toIntBase10 " 0000123")

    (123 == toIntBase10 "0000123 ")

    (123 == toIntBase10 " 0000123 ")

    (0 == toIntBase10 " 000000")

    (0 == toIntBase10 "000000 ")

    (0 == toIntBase10 " 000000 ")

  ];



  testToIntBase10Fails = testAllTrue [

    ( builtins.tryEval (toIntBase10 "") == { success = false; value = false; } )

    ( builtins.tryEval (toIntBase10 "123 123") == { success = false; value = false; } )

    ( builtins.tryEval (toIntBase10 "0 123") == { success = false; value = false; } )

    ( builtins.tryEval (toIntBase10 " 0d ") == { success = false; value = false; } )

    ( builtins.tryEval (toIntBase10 " foo ") == { success = false; value = false; } )

    ( builtins.tryEval (toIntBase10 " foo 123 ") == { success = false; value = false; } )

    ( builtins.tryEval (toIntBase10 " foo 00123 ") == { success = false; value = false; } )

    ( builtins.tryEval (toIntBase10 " foo00123 ") == { success = false; value = false; } )

  ];



# LISTS

lib/tests/modules.sh

+1 −1
Original line number Diff line number Diff line
@@ -162,7 +162,7 @@ checkConfigError 'A definition for option .* is not.*string or signed integer co 
# Check coerced value with unsound coercion

checkConfigOutput '^12$' config.value ./declare-coerced-value-unsound.nix

checkConfigError 'A definition for option .* is not of type .*. Definition values:\n\s*- In .*: "1000"' config.value ./declare-coerced-value-unsound.nix ./define-value-string-bigint.nix

checkConfigError 'Could not convert .* to int.' config.value ./declare-coerced-value-unsound.nix ./define-value-string-arbitrary.nix

checkConfigError 'Could not convert .* to int' config.value ./declare-coerced-value-unsound.nix ./define-value-string-arbitrary.nix



# Check mkAliasOptionModule.

checkConfigOutput '^true$' config.enable ./alias-with-priority.nix