diff options
| -rw-r--r-- | src/nix-env/profiles.cc | 17 | ||||
| -rw-r--r-- | tests/user-envs.sh | 9 |
2 files changed, 25 insertions, 1 deletions
diff --git a/src/nix-env/profiles.cc b/src/nix-env/profiles.cc index d8eb0ef52..1691dc099 100644 --- a/src/nix-env/profiles.cc +++ b/src/nix-env/profiles.cc @@ -80,7 +80,22 @@ Path createGeneration(Path profile, Path outPath) previous ones. */ int dummy; Generations gens = findGenerations(profile, dummy); - unsigned int num = gens.size() > 0 ? gens.back().number : 0; + + unsigned int num; + if (gens.size() > 0) { + /* Check existing generations whether they represent an + environment we already materialized before. In that case: + avoid cluttering the system with additional symlinks. */ + for (auto & gen : gens) { + if (readLink(gen.path) == outPath) { + return gen.path; + } + } + + num = gens.back().number; + } else { + num = 0; + } /* Create the new generation. Note that addPermRoot() blocks if the garbage collector is running to prevent the stuff we've diff --git a/tests/user-envs.sh b/tests/user-envs.sh index c9eed5a66..ad15ddc3e 100644 --- a/tests/user-envs.sh +++ b/tests/user-envs.sh @@ -99,6 +99,15 @@ if nix-env -q '*' | grep -q bar; then false; fi nix-env --list-generations test "$(nix-env --list-generations | wc -l)" -eq 7 +# Doing the same operation twice should result in the same generation, not an +# additional one. At this point we just brought back foo. Installing it again +# should not create a new generation. +nix-env -i foo + +# Count generations. +nix-env --list-generations +test "$(nix-env --list-generations | wc -l)" -eq 7 + # Switch to a specified generation. nix-env --switch-generation 7 [ "$(nix-store -q --resolve $profiles/test)" = "$oldGen" ] |