From 28ae24f3f738a50903bd9b9bf8eece84a1075c30 Mon Sep 17 00:00:00 2001 From: piegames Date: Thu, 11 Jul 2024 10:49:15 +0200 Subject: libexpr: Add experimental pipe operator The |> operator is a reverse function operator with low binding strength to replace lib.pipe. Implements RFC 148, see the RFC text for more details. Closes #438. Change-Id: I21df66e8014e0d4dd9753dd038560a2b0b7fd805 --- tests/unit/libexpr/trivial.cc | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) (limited to 'tests/unit/libexpr') diff --git a/tests/unit/libexpr/trivial.cc b/tests/unit/libexpr/trivial.cc index 19b62aff8..c984657fd 100644 --- a/tests/unit/libexpr/trivial.cc +++ b/tests/unit/libexpr/trivial.cc @@ -210,4 +210,40 @@ namespace nix { TEST_F(TrivialExpressionTest, orCantBeUsed) { ASSERT_THROW(eval("let or = 1; in or"), Error); } + + // pipes are gated behind an experimental feature flag + TEST_F(TrivialExpressionTest, pipeDisabled) { + ASSERT_THROW(eval("let add = l: r: l + r; in ''a'' |> add ''b''"), Error); + ASSERT_THROW(eval("let add = l: r: l + r; in ''a'' <| add ''b''"), Error); + } + + TEST_F(TrivialExpressionTest, pipeRight) { + ExperimentalFeatureSettings mockXpSettings; + mockXpSettings.set("experimental-features", "pipe-operator"); + + auto v = eval("let add = l: r: l + r; in ''a'' |> add ''b''", true, mockXpSettings); + ASSERT_THAT(v, IsStringEq("ba")); + v = eval("let add = l: r: l + r; in ''a'' |> add ''b'' |> add ''c''", true, mockXpSettings); + ASSERT_THAT(v, IsStringEq("cba")); + } + + TEST_F(TrivialExpressionTest, pipeLeft) { + ExperimentalFeatureSettings mockXpSettings; + mockXpSettings.set("experimental-features", "pipe-operator"); + + auto v = eval("let add = l: r: l + r; in add ''a'' <| ''b''", true, mockXpSettings); + ASSERT_THAT(v, IsStringEq("ab")); + v = eval("let add = l: r: l + r; in add ''a'' <| add ''b'' <| ''c''", true, mockXpSettings); + ASSERT_THAT(v, IsStringEq("abc")); + } + + TEST_F(TrivialExpressionTest, pipeMixed) { + ExperimentalFeatureSettings mockXpSettings; + mockXpSettings.set("experimental-features", "pipe-operator"); + + auto v = eval("let add = l: r: l + r; in add ''a'' <| ''b'' |> add ''c''", true, mockXpSettings); + ASSERT_THAT(v, IsStringEq("acb")); + v = eval("let add = l: r: l + r; in ''a'' |> add <| ''c''", true, mockXpSettings); + ASSERT_THAT(v, IsStringEq("ac")); + } } /* namespace nix */ -- cgit v1.2.3