treewide: make more settings conditionally available

Some settings only make sense on particular platforms, or only when a certain
experimental feature is enabled. Several of those were already conditionally
available. Do the same for a bunch more instead of silently ignoring them.
Exceptionally, the use-case-hack setting is not made conditional because it is
included in the test suite.

Change-Id: I29e66ad8ee6178a7c0eff9efb55c3410fae32514

1 files changed, 6 insertions, 3 deletions

diff --git a/src/nix/develop.cc b/src/nix/develop.cc
index d1615ecdc..81bc73e12 100644
--- a/src/nix/develop.cc
+++ b/src/nix/develop.cc
@@ -19,13 +19,16 @@ using namespace nix;
 struct DevelopSettings : Config
 {
     Setting<std::string> bashPrompt{this, "", "bash-prompt",
-        "The bash prompt (`PS1`) in `nix develop` shells."};
+        "The bash prompt (`PS1`) in `nix develop` shells.",
+        {}, true, Xp::NixCommand};
 
     Setting<std::string> bashPromptPrefix{this, "", "bash-prompt-prefix",
-        "Prefix prepended to the `PS1` environment variable in `nix develop` shells."};
+        "Prefix prepended to the `PS1` environment variable in `nix develop` shells.",
+        {}, true, Xp::NixCommand};
 
     Setting<std::string> bashPromptSuffix{this, "", "bash-prompt-suffix",
-        "Suffix appended to the `PS1` environment variable in `nix develop` shells."};
+        "Suffix appended to the `PS1` environment variable in `nix develop` shells.",
+        {}, true, Xp::NixCommand};
 };
 
 static DevelopSettings developSettings;