Move tests to separate directories, and document

Today, with the tests inside a `tests` intermingled with the
corresponding library's source code, we have a few problems:

- We have to be careful that wildcards don't end up with tests being
  built as part of Nix proper, or test headers being installed as part
  of Nix proper.

- Tests in libraries but not executables is not right:

  - It means each executable runs the previous unit tests again, because
    it needs the libraries.

  - It doesn't work right on Windows, which doesn't want you to load a
    DLL just for the side global variable . It could be made to work
    with the dlopen equivalent, but that's gross!

This reorg solves these problems.

There is a remaining problem which is that sibbling headers (like
`hash.hh` the test header vs `hash.hh` the main `libnixutil` header) end
up shadowing each other. This PR doesn't solve that. That is left as
future work for a future PR.

Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>

(cherry picked from commit 91b6833686a6a6d9eac7f3f66393ec89ef1d3b57)
(cherry picked from commit a61e42adb528b3d40ce43e07c79368d779a8b624)

1 files changed, 77 insertions, 0 deletions

diff --git a/tests/unit/libutil/hash.cc b/tests/unit/libutil/hash.cc
new file mode 100644
index 000000000..1f40edc95
--- /dev/null
+++ b/tests/unit/libutil/hash.cc
@@ -0,0 +1,77 @@
+#include <regex>
+
+#include <gtest/gtest.h>
+
+#include "hash.hh"
+
+namespace nix {
+
+    /* ----------------------------------------------------------------------------
+     * hashString
+     * --------------------------------------------------------------------------*/
+
+    TEST(hashString, testKnownMD5Hashes1) {
+        // values taken from: https://tools.ietf.org/html/rfc1321
+        auto s1 = "";
+        auto hash = hashString(HashType::htMD5, s1);
+        ASSERT_EQ(hash.to_string(Base::Base16, true), "md5:d41d8cd98f00b204e9800998ecf8427e");
+    }
+
+    TEST(hashString, testKnownMD5Hashes2) {
+        // values taken from: https://tools.ietf.org/html/rfc1321
+        auto s2 = "abc";
+        auto hash = hashString(HashType::htMD5, s2);
+        ASSERT_EQ(hash.to_string(Base::Base16, true), "md5:900150983cd24fb0d6963f7d28e17f72");
+    }
+
+    TEST(hashString, testKnownSHA1Hashes1) {
+        // values taken from: https://tools.ietf.org/html/rfc3174
+        auto s = "abc";
+        auto hash = hashString(HashType::htSHA1, s);
+        ASSERT_EQ(hash.to_string(Base::Base16, true),"sha1:a9993e364706816aba3e25717850c26c9cd0d89d");
+    }
+
+    TEST(hashString, testKnownSHA1Hashes2) {
+        // values taken from: https://tools.ietf.org/html/rfc3174
+        auto s = "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq";
+        auto hash = hashString(HashType::htSHA1, s);
+        ASSERT_EQ(hash.to_string(Base::Base16, true),"sha1:84983e441c3bd26ebaae4aa1f95129e5e54670f1");
+    }
+
+    TEST(hashString, testKnownSHA256Hashes1) {
+        // values taken from: https://tools.ietf.org/html/rfc4634
+        auto s = "abc";
+
+        auto hash = hashString(HashType::htSHA256, s);
+        ASSERT_EQ(hash.to_string(Base::Base16, true),
+                "sha256:ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad");
+    }
+
+    TEST(hashString, testKnownSHA256Hashes2) {
+        // values taken from: https://tools.ietf.org/html/rfc4634
+        auto s = "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq";
+        auto hash = hashString(HashType::htSHA256, s);
+        ASSERT_EQ(hash.to_string(Base::Base16, true),
+                "sha256:248d6a61d20638b8e5c026930c3e6039a33ce45964ff2167f6ecedd419db06c1");
+    }
+
+    TEST(hashString, testKnownSHA512Hashes1) {
+        // values taken from: https://tools.ietf.org/html/rfc4634
+        auto s = "abc";
+        auto hash = hashString(HashType::htSHA512, s);
+        ASSERT_EQ(hash.to_string(Base::Base16, true),
+                "sha512:ddaf35a193617abacc417349ae20413112e6fa4e89a9"
+                "7ea20a9eeee64b55d39a2192992a274fc1a836ba3c23a3feebbd"
+                "454d4423643ce80e2a9ac94fa54ca49f");
+    }
+    TEST(hashString, testKnownSHA512Hashes2) {
+        // values taken from: https://tools.ietf.org/html/rfc4634
+        auto s = "abcdefghbcdefghicdefghijdefghijkefghijklfghijklmghijklmnhijklmnoijklmnopjklmnopqklmnopqrlmnopqrsmnopqrstnopqrstu";
+
+        auto hash = hashString(HashType::htSHA512, s);
+        ASSERT_EQ(hash.to_string(Base::Base16, true),
+                "sha512:8e959b75dae313da8cf4f72814fc143f8f7779c6eb9f7fa1"
+                "7299aeadb6889018501d289e4900f7e4331b99dec4b5433a"
+                "c7d329eeb6dd26545e96e55b874be909");
+    }
+}