push sheeet

pkgs/build-support/setup-hooks/arrayUtilities/sortArray/package.nix

@@ -0,0 +1,11 @@
+{
+  callPackages,
+  isDeclaredArray,
+  makeSetupHook,
+}:
+makeSetupHook {
+  name = "sortArray";
+  propagatedBuildInputs = [ isDeclaredArray ];
+  passthru.tests = callPackages ./tests.nix { };
+  meta.description = "Sorts an array";
+} ./sortArray.bash

pkgs/build-support/setup-hooks/arrayUtilities/sortArray/sortArray.bash

@@ -0,0 +1,53 @@
+# shellcheck shell=bash
+
+# sortArray
+# Sorts the indexed array referenced by inputArrRef and stores the result in the indexed array referenced by
+# outputArrRef.
+#
+# Arguments:
+# - inputArrRef: a reference to an indexed array (not mutated, may alias outputArrRef)
+# - outputArrRef: a reference to an indexed array (contents are replaced entirely, may alias inputArrRef)
+#
+# Returns 0.
+sortArray() {
+  if (($# != 2)); then
+    nixErrorLog "expected two arguments!"
+    nixErrorLog "usage: sortArray inputArrRef outputArrRef"
+    exit 1
+  fi
+
+  local -rn inputArrRef="$1"
+  local -rn outputArrRef="$2"
+
+  if ! isDeclaredArray "${!inputArrRef}"; then
+    nixErrorLog "first argument inputArrRef must be a reference to an indexed array"
+    exit 1
+  elif ! isDeclaredArray "${!outputArrRef}"; then
+    nixErrorLog "second argument outputArrRef must be a reference to an indexed array"
+    exit 1
+  fi
+
+  local -a sortedArray=()
+
+  # Guard on the length of the input array, as empty array will expand to nothing, but printf will still see it as an
+  # argument, producing an empty string.
+  if ((${#inputArrRef[@]} > 0)); then
+    # NOTE from Bash's printf documentation:
+    #   The format is reused as necessary to consume all of the arguments. If the format requires more arguments than
+    #   are supplied, the extra format specifications behave as if a zero value or null string, as appropriate, had
+    #   been supplied.
+    #   - https://www.gnu.org/software/bash/manual/html_node/Bash-Builtins.html#index-printf
+    # NOTE from sort manpage:
+    #   If you use a non-POSIX locale (e.g., by setting LC_ALL to 'en_US'), then sort may produce output that is sorted
+    #   differently than you're accustomed to. In that case, set the LC_ALL environment variable to 'C'. Setting only
+    #   LC_COLLATE has two problems. First, it is ineffective if LC_ALL is also set. Second, it has undefined behavior
+    #   if LC_CTYPE (or LANG, if LC_CTYPE is unset) is set to an incompatible value. For example, you get undefined
+    #   behavior if LC_CTYPE is ja_JP.PCK but LC_COLLATE is en_US.UTF-8.
+    #   - https://www.gnu.org/software/coreutils/manual/html_node/sort-invocation.html#FOOT1
+    mapfile -d $'\0' -t sortedArray < <(printf '%s\0' "${inputArrRef[@]}" | LC_ALL=C sort --stable --zero-terminated)
+  fi
+
+  outputArrRef=("${sortedArray[@]}")
+
+  return 0
+}

pkgs/build-support/setup-hooks/arrayUtilities/sortArray/tests.nix

@@ -0,0 +1,178 @@
+# NOTE: Tests related to sortArray go here.
+{
+  lib,
+  sortArray,
+  testers,
+}:
+let
+  inherit (lib.attrsets) recurseIntoAttrs;
+  inherit (testers) shellcheck shfmt testEqualArrayOrMap;
+  check =
+    {
+      name,
+      valuesArray,
+      expectedArray,
+    }:
+    (testEqualArrayOrMap {
+      inherit name valuesArray expectedArray;
+      script = ''
+        set -eu
+        nixLog "running sortArray with valuesArray to populate actualArray"
+        sortArray valuesArray actualArray
+      '';
+    }).overrideAttrs
+      (prevAttrs: {
+        nativeBuildInputs = prevAttrs.nativeBuildInputs or [ ] ++ [ sortArray ];
+      });
+
+  checkInPlace =
+    {
+      name,
+      valuesArray,
+      expectedArray,
+    }:
+    (testEqualArrayOrMap {
+      inherit name valuesArray expectedArray;
+      script = ''
+        set -eu
+        nixLog "running sortArray with valuesArray as input and output"
+        sortArray valuesArray valuesArray
+        nixLog "copying valuesArray to actualArray"
+        actualArray=("''${valuesArray[@]}")
+      '';
+    }).overrideAttrs
+      (prevAttrs: {
+        nativeBuildInputs = prevAttrs.nativeBuildInputs or [ ] ++ [ sortArray ];
+      });
+in
+recurseIntoAttrs {
+  shellcheck = shellcheck {
+    name = "sortArray";
+    src = ./sortArray.bash;
+  };
+
+  shfmt = shfmt {
+    name = "sortArray";
+    src = ./sortArray.bash;
+  };
+
+  empty = check {
+    name = "empty";
+    valuesArray = [ ];
+    expectedArray = [ ];
+  };
+
+  singleton = check {
+    name = "singleton";
+    valuesArray = [ "apple" ];
+    expectedArray = [ "apple" ];
+  };
+
+  oneDuplicate = check {
+    name = "oneDuplicate";
+    valuesArray = [
+      "apple"
+      "apple"
+    ];
+    expectedArray = [
+      "apple"
+      "apple"
+    ];
+  };
+
+  oneUnique = check {
+    name = "oneUnique";
+    valuesArray = [
+      "bee"
+      "apple"
+      "bee"
+    ];
+    expectedArray = [
+      "apple"
+      "bee"
+      "bee"
+    ];
+  };
+
+  duplicatesWithSpacesAndLineBreaks = check {
+    name = "duplicatesWithSpacesAndLineBreaks";
+    valuesArray = [
+      "dog"
+      "bee"
+      ''
+        line
+        break
+      ''
+      "cat"
+      "zebra"
+      "bee"
+      "cat"
+      "elephant"
+      "dog with spaces"
+      ''
+        line
+        break
+      ''
+    ];
+    expectedArray = [
+      "bee"
+      "bee"
+      "cat"
+      "cat"
+      "dog"
+      "dog with spaces"
+      "elephant"
+      # NOTE: lead whitespace is removed, so the following entries start with `l`.
+      ''
+        line
+        break
+      ''
+      ''
+        line
+        break
+      ''
+      "zebra"
+    ];
+  };
+
+  duplicatesWithSpacesAndLineBreaksInPlace = checkInPlace {
+    name = "duplicatesWithSpacesAndLineBreaksInPlace";
+    valuesArray = [
+      "dog"
+      "bee"
+      ''
+        line
+        break
+      ''
+      "cat"
+      "zebra"
+      "bee"
+      "cat"
+      "elephant"
+      "dog with spaces"
+      ''
+        line
+        break
+      ''
+    ];
+    expectedArray = [
+      "bee"
+      "bee"
+      "cat"
+      "cat"
+      "dog"
+      "dog with spaces"
+      "elephant"
+      # NOTE: lead whitespace is removed, so the following entries start with `l`.
+      ''
+        line
+        break
+      ''
+      ''
+        line
+        break
+      ''
+      "zebra"
+    ];
+  };
+}