treewide: handle prePhases __structuredAttrs-agnostically

Always specify the prePhases attribute as a list instead of a string.

Append elements to the prePhases Bash variable using appendToVar
instead of string or Bash array concatenation.

pkgs/applications/graphics/gimp/plugins/default.nix

@@ -17,7 +17,7 @@ let
   pluginDerivation = attrs: let
     name = attrs.name or "${attrs.pname}-${attrs.version}";
   in stdenv.mkDerivation ({
-    prePhases = "extraLib";
+    prePhases = [ "extraLib" ];
     extraLib = ''
       installScripts(){
         mkdir -p $out/${gimp.targetScriptDir}/${name};
@@ -54,7 +54,7 @@ let
   });
 
   scriptDerivation = {src, ...}@attrs : pluginDerivation ({
-    prePhases = "extraLib";
+    prePhases = [ "extraLib" ];
     dontUnpack = true;
     installPhase = ''
       runHook preInstall

pkgs/build-support/release/debian-build.nix

@@ -18,7 +18,7 @@ vmTools.runInLinuxImage (stdenv.mkDerivation (
 
     prefix = "/usr";
 
-    prePhases = "installExtraDebsPhase sysInfoPhase";
+    prePhases = [ "installExtraDebsPhase" "sysInfoPhase" ];
   }
 
   // removeAttrs args ["vmTools" "lib"] //

pkgs/build-support/setup-hooks/keep-build-tree.sh

@@ -1,4 +1,4 @@
-prePhases+=" moveBuildDir"
+appendToVar prePhases moveBuildDir
 
 moveBuildDir() {
     mkdir -p $out/.build

pkgs/build-support/setup-hooks/move-build-tree.sh

@@ -1,4 +1,4 @@
-prePhases+=" moveBuildDir"
+appendToVar prePhases moveBuildDir
 
 moveBuildDir() {
     mkdir -p $out/.build

pkgs/by-name/ha/hare/setup-hook.sh

@@ -18,7 +18,7 @@ echoCmd "HAREPATH" "$HAREPATH"
 echoCmd "hare" "$(command -v hare)"
 echoCmd "hare-native" "$(command -v hare-native)"
 '
-prePhases+=("hareSetStdlibPhase" "hareInfoPhase")
+appendToVar prePhases hareSetStdlibPhase hareInfoPhase
 
 readonly hare_unconditional_flags="@hare_unconditional_flags@"
 case "${hareBuildType:-"release"}" in

pkgs/development/compilers/dotnet/dotnet-sdk-setup-hook.sh

@@ -73,6 +73,6 @@ configureNuget() {
 }
 
 if [[ -z ${dontConfigureNuget-} ]]; then
-    prePhases+=(createNugetDirs)
+    appendToVar prePhases createNugetDirs
     preConfigurePhases+=(configureNuget)
 fi

pkgs/development/libraries/qt-5/hooks/qmake-hook.sh

@@ -20,7 +20,7 @@ qmakePrePhase() {
     # do the stripping ourselves (needed for separateDebugInfo)
     prependToVar qmakeFlags "CONFIG+=nostrip"
 }
-prePhases+=" qmakePrePhase"
+appendToVar prePhases qmakePrePhase
 
 qmakeConfigurePhase() {
     runHook preConfigure

pkgs/development/libraries/qt-5/hooks/qtbase-setup-hook.sh

@@ -107,6 +107,6 @@ qtPreHook() {
         exit 1
     fi
 }
-prePhases+=" qtPreHook"
+appendToVar prePhases qtPreHook
 
 fi

pkgs/development/libraries/qt-6/hooks/qmake-hook.sh

@@ -13,7 +13,7 @@ qmakePrePhase() {
       "NIX_OUTPUT_QML=${!outputBin}/${qtQmlPrefix:?}" \
       "NIX_OUTPUT_PLUGIN=${!outputBin}/${qtPluginPrefix:?}"
 }
-prePhases+=" qmakePrePhase"
+appendToVar prePhases qmakePrePhase
 
 qmakeConfigurePhase() {
     runHook preConfigure

pkgs/development/libraries/qt-6/hooks/qtbase-setup-hook.sh

@@ -81,7 +81,7 @@ else # Only set up Qt once.
             exit 1
         fi
     }
-    prePhases+=" qtPreHook"
+    appendToVar prePhases qtPreHook
 
     addQtModulePrefix() {
         addToSearchPath QT_ADDITIONAL_PACKAGES_PREFIX_PATH $1