diff options
| -rw-r--r-- | doc/manual/src/release-notes/rl-next.md | 1 | ||||
| -rw-r--r-- | src/libexpr/primops.cc | 25 | ||||
| -rw-r--r-- | src/libexpr/tests/error_traces.cc | 2 | ||||
| -rw-r--r-- | tests/lang/eval-okay-replacestrings.exp | 2 | ||||
| -rw-r--r-- | tests/lang/eval-okay-replacestrings.nix | 1 |
5 files changed, 17 insertions, 14 deletions
diff --git a/doc/manual/src/release-notes/rl-next.md b/doc/manual/src/release-notes/rl-next.md index bc0d41bdf..f92625887 100644 --- a/doc/manual/src/release-notes/rl-next.md +++ b/doc/manual/src/release-notes/rl-next.md @@ -4,3 +4,4 @@ The number of parallel downloads (also known as substitutions) has been separated from the [`--max-jobs` setting](../command-ref/conf-file.md#conf-max-jobs). The new setting is called [`max-substitution-jobs`](../command-ref/conf-file.md#conf-max-substitution-jobs). The number of parallel downloads is now set to 16 by default (previously, the default was 1 due to the coupling to build jobs). +- The function `builtins.replaceStrings` is now lazy in the value of its second argument `to`, that is a replacee in `to` is only evaluated when its corresponding pattern in `from` is matched in the string `s`. diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc index 341962dc9..c28e7cbc7 100644 --- a/src/libexpr/primops.cc +++ b/src/libexpr/primops.cc @@ -3908,13 +3908,8 @@ static void prim_replaceStrings(EvalState & state, const PosIdx pos, Value * * a for (auto elem : args[0]->listItems()) from.emplace_back(state.forceString(*elem, pos, "while evaluating one of the strings to replace passed to builtins.replaceStrings")); - std::vector<std::pair<std::string, NixStringContext>> to; - to.reserve(args[1]->listSize()); - for (auto elem : args[1]->listItems()) { - NixStringContext ctx; - auto s = state.forceString(*elem, ctx, pos, "while evaluating one of the replacement strings passed to builtins.replaceStrings"); - to.emplace_back(s, std::move(ctx)); - } + std::unordered_map<size_t, std::string> cache; + auto to = args[1]->listItems(); NixStringContext context; auto s = state.forceString(*args[2], context, pos, "while evaluating the third argument passed to builtins.replaceStrings"); @@ -3925,10 +3920,19 @@ static void prim_replaceStrings(EvalState & state, const PosIdx pos, Value * * a bool found = false; auto i = from.begin(); auto j = to.begin(); - for (; i != from.end(); ++i, ++j) + size_t j_index = 0; + for (; i != from.end(); ++i, ++j, ++j_index) if (s.compare(p, i->size(), *i) == 0) { found = true; - res += j->first; + auto v = cache.find(j_index); + if (v == cache.end()) { + NixStringContext ctx; + auto ts = state.forceString(**j, ctx, pos, "while evaluating one of the replacement strings passed to builtins.replaceStrings"); + v = (cache.emplace(j_index, ts)).first; + for (auto& path : ctx) + context.insert(path); + } + res += v->second; if (i->empty()) { if (p < s.size()) res += s[p]; @@ -3936,9 +3940,6 @@ static void prim_replaceStrings(EvalState & state, const PosIdx pos, Value * * a } else { p += i->size(); } - for (auto& path : j->second) - context.insert(path); - j->second.clear(); break; } if (!found) { diff --git a/src/libexpr/tests/error_traces.cc b/src/libexpr/tests/error_traces.cc index 24e95ac39..285651256 100644 --- a/src/libexpr/tests/error_traces.cc +++ b/src/libexpr/tests/error_traces.cc @@ -171,7 +171,7 @@ namespace nix { hintfmt("value is %s while a string was expected", "an integer"), hintfmt("while evaluating one of the strings to replace passed to builtins.replaceStrings")); - ASSERT_TRACE2("replaceStrings [ \"old\" ] [ true ] {}", + ASSERT_TRACE2("replaceStrings [ \"oo\" ] [ true ] \"foo\"", TypeError, hintfmt("value is %s while a string was expected", "a Boolean"), hintfmt("while evaluating one of the replacement strings passed to builtins.replaceStrings")); diff --git a/tests/lang/eval-okay-replacestrings.exp b/tests/lang/eval-okay-replacestrings.exp index 72e8274d8..eac67c5fe 100644 --- a/tests/lang/eval-okay-replacestrings.exp +++ b/tests/lang/eval-okay-replacestrings.exp @@ -1 +1 @@ -[ "faabar" "fbar" "fubar" "faboor" "fubar" "XaXbXcX" "X" "a_b" ] +[ "faabar" "fbar" "fubar" "faboor" "fubar" "XaXbXcX" "X" "a_b" "fubar" ] diff --git a/tests/lang/eval-okay-replacestrings.nix b/tests/lang/eval-okay-replacestrings.nix index bd8031fc0..a803e6519 100644 --- a/tests/lang/eval-okay-replacestrings.nix +++ b/tests/lang/eval-okay-replacestrings.nix @@ -8,4 +8,5 @@ with builtins; (replaceStrings [""] ["X"] "abc") (replaceStrings [""] ["X"] "") (replaceStrings ["-"] ["_"] "a-b") + (replaceStrings ["oo" "XX"] ["u" (throw "unreachable")] "foobar") ] |