treewide: use optionalString instead of 'then ""'

14 files changed, 21 insertions, 24 deletions

diff --git a/pkgs/development/compilers/purescript/purescript/default.nix b/pkgs/development/compilers/purescript/purescript/default.nix
index d7c8394a57b..fd3d1a810a5 100644
--- a/pkgs/development/compilers/purescript/purescript/default.nix
+++ b/pkgs/development/compilers/purescript/purescript/default.nix
@@ -7,10 +7,7 @@ let
   dynamic-linker = stdenv.cc.bintools.dynamicLinker;
 
   patchelf = libPath :
-    if stdenv.isDarwin
-      then ""
-      else
-        ''
+    lib.optionalString (!stdenv.isDarwin) ''
           chmod u+w $PURS
           patchelf --interpreter ${dynamic-linker} --set-rpath ${libPath} $PURS
           chmod u-w $PURS
diff --git a/pkgs/development/interpreters/acl2/libipasirglucose4/default.nix b/pkgs/development/interpreters/acl2/libipasirglucose4/default.nix
index dc8308267f4..c31e0dbe67f 100644
--- a/pkgs/development/interpreters/acl2/libipasirglucose4/default.nix
+++ b/pkgs/development/interpreters/acl2/libipasirglucose4/default.nix
@@ -24,7 +24,7 @@ stdenv.mkDerivation rec {
 
   postBuild = ''
     $CXX -shared -o ${libname} \
-        ${if stdenv.cc.isClang then "" else "-Wl,-soname,${libname}"} \
+        ${lib.optionalString (!stdenv.cc.isClang) "-Wl,-soname,${libname}"} \
         ipasirglucoseglue.o libipasirglucose4.a
   '';
 
diff --git a/pkgs/development/interpreters/python/mk-python-derivation.nix b/pkgs/development/interpreters/python/mk-python-derivation.nix
index 17b5667e8ee..79e45b8dc39 100644
--- a/pkgs/development/interpreters/python/mk-python-derivation.nix
+++ b/pkgs/development/interpreters/python/mk-python-derivation.nix
@@ -118,7 +118,7 @@ let
 
     optionalLocation = let
         pos = builtins.unsafeGetAttrPos (if attrs ? "pname" then "pname" else "name") attrs;
-      in if pos == null then "" else " at ${pos.file}:${toString pos.line}:${toString pos.column}";
+      in lib.optionalString (pos != null) " at ${pos.file}:${toString pos.line}:${toString pos.column}";
 
     leftPadName = name: against: let
         len = lib.max (lib.stringLength name) (lib.stringLength against);
diff --git a/pkgs/development/interpreters/python/wrapper.nix b/pkgs/development/interpreters/python/wrapper.nix
index b36662335ab..f5f9b03e0fd 100644
--- a/pkgs/development/interpreters/python/wrapper.nix
+++ b/pkgs/development/interpreters/python/wrapper.nix
@@ -42,7 +42,7 @@ let
             if [ -f "$prg" ]; then
               rm -f "$out/bin/$prg"
               if [ -x "$prg" ]; then
-                makeWrapper "$path/bin/$prg" "$out/bin/$prg" --set NIX_PYTHONPREFIX "$out" --set NIX_PYTHONEXECUTABLE ${pythonExecutable} --set NIX_PYTHONPATH ${pythonPath} ${if permitUserSite then "" else ''--set PYTHONNOUSERSITE "true"''} ${lib.concatStringsSep " " makeWrapperArgs}
+                makeWrapper "$path/bin/$prg" "$out/bin/$prg" --set NIX_PYTHONPREFIX "$out" --set NIX_PYTHONEXECUTABLE ${pythonExecutable} --set NIX_PYTHONPATH ${pythonPath} ${lib.optionalString (!permitUserSite) ''--set PYTHONNOUSERSITE "true"''} ${lib.concatStringsSep " " makeWrapperArgs}
               fi
             fi
           done
diff --git a/pkgs/development/libraries/ffmpeg/generic.nix b/pkgs/development/libraries/ffmpeg/generic.nix
index 12e59c939af..4c31b82f310 100644
--- a/pkgs/development/libraries/ffmpeg/generic.nix
+++ b/pkgs/development/libraries/ffmpeg/generic.nix
@@ -330,7 +330,7 @@ assert buildPostproc -> buildAvutil;
 assert buildSwscale -> buildAvutil;
 
 stdenv.mkDerivation (finalAttrs: {
-  pname = "ffmpeg" + (if ffmpegVariant == "small" then "" else "-${ffmpegVariant}");
+  pname = "ffmpeg" + (optionalString (ffmpegVariant != "small") "-${ffmpegVariant}");
   inherit version;
 
   src = fetchgit {
diff --git a/pkgs/development/libraries/opencv/tests.nix b/pkgs/development/libraries/opencv/tests.nix
index 03a89db0882..d1966b1a4aa 100644
--- a/pkgs/development/libraries/opencv/tests.nix
+++ b/pkgs/development/libraries/opencv/tests.nix
@@ -39,7 +39,7 @@ let
     "stitching"
     "video"
   ] ++ lib.optionals (!stdenv.isAarch64 && enableGStreamer) [ "gapi" ];
-  testRunner = if stdenv.isDarwin then "" else "${lib.getExe xvfb-run} -a ";
+  testRunner = lib.optionalString (!stdenv.isDarwin) "${lib.getExe xvfb-run} -a ";
   testsPreparation = ''
     touch $out
     # several tests want a write access, so we have to copy files
diff --git a/pkgs/development/libraries/qt-4.x/4.8/default.nix b/pkgs/development/libraries/qt-4.x/4.8/default.nix
index 68a300ac250..a8257a36d39 100644
--- a/pkgs/development/libraries/qt-4.x/4.8/default.nix
+++ b/pkgs/development/libraries/qt-4.x/4.8/default.nix
@@ -173,9 +173,9 @@ stdenv.mkDerivation rec {
     "-make" "libs" "-make" "tools" "-make" "translations"
     "-no-phonon" "-no-webkit" "-no-multimedia" "-audio-backend"
   ]) ++ [
-    "-${if demos then "" else "no"}make" "demos"
-    "-${if examples then "" else "no"}make" "examples"
-    "-${if docs then "" else "no"}make" "docs"
+    "-${lib.optionalString (!demos) "no"}make" "demos"
+    "-${lib.optionalString (!examples) "no"}make" "examples"
+    "-${lib.optionalString (!docs) "no"}make" "docs"
   ] ++ lib.optional developerBuild "-developer-build"
     ++ lib.optionals stdenv.hostPlatform.isDarwin [ platformFlag "unsupported/macx-clang-libc++" ]
     ++ lib.optionals stdenv.hostPlatform.isWindows [ platformFlag "win32-g++-4.6" ];
diff --git a/pkgs/development/mobile/titaniumenv/build-app.nix b/pkgs/development/mobile/titaniumenv/build-app.nix
index fa2eeae00b5..42b70c64abe 100644
--- a/pkgs/development/mobile/titaniumenv/build-app.nix
+++ b/pkgs/development/mobile/titaniumenv/build-app.nix
@@ -158,8 +158,7 @@ stdenv.mkDerivation ({
 
   installPhase = ''
     ${if target == "android" then ''
-      ${if release then ""
-      else ''
+      ${lib.optionalString (!release) ''
         cp "$(ls build/android/bin/*.apk | grep -v '\-unsigned.apk')" $out
       ''}
 
diff --git a/pkgs/development/python-modules/azure-common/default.nix b/pkgs/development/python-modules/azure-common/default.nix
index 504748f033f..47d0039e5e4 100644
--- a/pkgs/development/python-modules/azure-common/default.nix
+++ b/pkgs/development/python-modules/azure-common/default.nix
@@ -23,7 +23,7 @@ buildPythonPackage rec {
     azure-nspkg
   ] ++ lib.optionals (!isPy3k) [ setuptools ]; # need for namespace lookup
 
-  postInstall = if isPy3k then "" else ''
+  postInstall = lib.optionalString (!isPy3k) ''
     echo "__import__('pkg_resources').declare_namespace(__name__)" >> "$out/lib/${python.libPrefix}"/site-packages/azure/__init__.py
   '';
 
diff --git a/pkgs/development/python-modules/azure-mgmt-common/default.nix b/pkgs/development/python-modules/azure-mgmt-common/default.nix
index 28043046d8a..dfd7ac2a3f0 100644
--- a/pkgs/development/python-modules/azure-mgmt-common/default.nix
+++ b/pkgs/development/python-modules/azure-mgmt-common/default.nix
@@ -26,7 +26,7 @@ buildPythonPackage rec {
     msrestazure
   ];
 
-  postInstall = if isPy3k then "" else ''
+  postInstall = pkgs.lib.optionalString (!isPy3k) ''
     echo "__import__('pkg_resources').declare_namespace(__name__)" >> "$out/lib/${python.libPrefix}"/site-packages/azure/mgmt/__init__.py
     echo "__import__('pkg_resources').declare_namespace(__name__)" >> "$out/lib/${python.libPrefix}"/site-packages/azure/__init__.py
   '';
diff --git a/pkgs/development/python-modules/tensorflow/bin.nix b/pkgs/development/python-modules/tensorflow/bin.nix
index a988a39c388..5bb66896504 100644
--- a/pkgs/development/python-modules/tensorflow/bin.nix
+++ b/pkgs/development/python-modules/tensorflow/bin.nix
@@ -53,7 +53,7 @@ in buildPythonPackage {
   disabled = pythonAtLeast "3.11";
 
   src = let
-    pyVerNoDot = lib.strings.stringAsChars (x: if x == "." then "" else x) python.pythonVersion;
+    pyVerNoDot = lib.strings.stringAsChars (x: lib.optionalString (x != ".") x) python.pythonVersion;
     platform = if stdenv.isDarwin then "mac" else "linux";
     unit = if cudaSupport then "gpu" else "cpu";
     key = "${platform}_py_${pyVerNoDot}_${unit}";
diff --git a/pkgs/development/ruby-modules/bundled-common/default.nix b/pkgs/development/ruby-modules/bundled-common/default.nix
index aa903a5637c..01d27b91561 100644
--- a/pkgs/development/ruby-modules/bundled-common/default.nix
+++ b/pkgs/development/ruby-modules/bundled-common/default.nix
@@ -70,11 +70,12 @@ let
       assert gemFiles.gemdir != null; "cp -a ${gemFiles.gemdir}/* $out/") #*/
   );
 
-  maybeCopyAll = pkgname: if pkgname == null then "" else
-  let
-    mainGem = gems.${pkgname} or (throw "bundlerEnv: gem ${pkgname} not found");
-  in
-    copyIfBundledByPath mainGem;
+  maybeCopyAll = pkgname: lib.optionalString (pkgname != null) (
+    let
+      mainGem = gems.${pkgname} or (throw "bundlerEnv: gem ${pkgname} not found");
+    in
+      copyIfBundledByPath mainGem
+  );
 
   # We have to normalize the Gemfile.lock, otherwise bundler tries to be
   # helpful by doing so at run time, causing executables to immediately bail
diff --git a/pkgs/development/ruby-modules/gem/default.nix b/pkgs/development/ruby-modules/gem/default.nix
index 7105663413a..d57eeb2ea05 100644
--- a/pkgs/development/ruby-modules/gem/default.nix
+++ b/pkgs/development/ruby-modules/gem/default.nix
@@ -224,7 +224,7 @@ stdenv.mkDerivation ((builtins.removeAttrs attrs ["source"]) // {
     pushd $out/${ruby.gemPath}
     find doc/ -iname created.rid -delete -print
     find gems/*/ext/ extensions/ \( -iname Makefile -o -iname mkmf.log -o -iname gem_make.out \) -delete -print
-    ${if keepGemCache then "" else "rm -fvr cache"}
+    ${lib.optionalString (!keepGemCache) "rm -fvr cache"}
     popd
 
     # write out metadata and binstubs
diff --git a/pkgs/development/tools/misc/distcc/default.nix b/pkgs/development/tools/misc/distcc/default.nix
index b7270f79c43..312f6932858 100644
--- a/pkgs/development/tools/misc/distcc/default.nix
+++ b/pkgs/development/tools/misc/distcc/default.nix
@@ -26,7 +26,7 @@ let
       configureFlagsArray=( CFLAGS="-O2 -fno-strict-aliasing"
                             CXXFLAGS="-O2 -fno-strict-aliasing"
           --mandir=$out/share/man
-                            ${if sysconfDir == "" then "" else "--sysconfdir=${sysconfDir}"}
+                            ${lib.optionalString (sysconfDir != "") "--sysconfdir=${sysconfDir}"}
                             ${lib.optionalString static "LDFLAGS=-static"}
                             ${lib.withFeature (static == true || popt == null) "included-popt"}
                             ${lib.withFeature (avahi != null) "avahi"}