Crypto: Refactor hash computation

... by renaming HashGenerator to (incremental) Hasher and
dropping support for Git/MD5 hashes. The Hasher does not
expose the actual hash implementation.

4 files changed, 35 insertions, 64 deletions

diff --git a/test/buildtool/crypto/TARGETS b/test/buildtool/crypto/TARGETS
index 44800068..c12fa855 100644
--- a/test/buildtool/crypto/TARGETS
+++ b/test/buildtool/crypto/TARGETS
@@ -1,11 +1,11 @@
-{ "crypto":
+{ "hasher":
   { "type": ["@", "rules", "CC/test", "test"]
-  , "name": ["crypto"]
-  , "srcs": ["crypto.test.cpp"]
+  , "name": ["hasher"]
+  , "srcs": ["hasher.test.cpp"]
   , "deps":
     [ ["@", "catch2", "", "catch2"]
     , ["test", "catch-main"]
-    , ["src/buildtool/crypto", "hash_generator"]
+    , ["src/buildtool/crypto", "hasher"]
     ]
   , "stage": ["test", "buildtool", "crypto"]
   }
@@ -21,5 +21,5 @@
   , "stage": ["test", "buildtool", "crypto"]
   }
 , "TESTS":
-  {"type": "install", "tainted": ["test"], "deps": ["crypto", "hash_function"]}
+  {"type": "install", "tainted": ["test"], "deps": ["hasher", "hash_function"]}
 }
diff --git a/test/buildtool/crypto/crypto.test.cpp b/test/buildtool/crypto/crypto.test.cpp
deleted file mode 100644
index 78bea66b..00000000
--- a/test/buildtool/crypto/crypto.test.cpp
+++ /dev/null
@@ -1,57 +0,0 @@
-#include <algorithm>
-
-#include "catch2/catch.hpp"
-#include "src/buildtool/crypto/hash_generator.hpp"
-
-template <HashGenerator::HashType type>
-void test_single_hash(std::string const& bytes, std::string const& result) {
-    HashGenerator hash_gen{type};
-    auto digest = hash_gen.Run(bytes);
-    CHECK(digest.HexString() == result);
-}
-
-template <HashGenerator::HashType type>
-void test_increment_hash(std::string const& bytes, std::string const& result) {
-    HashGenerator hash_gen{type};
-    auto hasher = hash_gen.IncrementalHasher();
-    hasher.Update(bytes);
-    auto digest = std::move(hasher).Finalize();
-    CHECK(digest);
-    CHECK(digest->HexString() == result);
-}
-
-TEST_CASE("Hash Generator", "[crypto]") {
-    std::string bytes{"test"};
-
-    SECTION("MD5") {
-        // same as: echo -n test | md5sum
-        test_single_hash<HashGenerator::HashType::MD5>(
-            bytes, "098f6bcd4621d373cade4e832627b4f6");
-        test_increment_hash<HashGenerator::HashType::MD5>(
-            bytes, "098f6bcd4621d373cade4e832627b4f6");
-    }
-
-    SECTION("SHA-1") {
-        // same as: echo -n test | sha1sum
-        test_single_hash<HashGenerator::HashType::SHA1>(
-            bytes, "a94a8fe5ccb19ba61c4c0873d391e987982fbbd3");
-        test_increment_hash<HashGenerator::HashType::SHA1>(
-            bytes, "a94a8fe5ccb19ba61c4c0873d391e987982fbbd3");
-    }
-
-    SECTION("SHA-256") {
-        // same as: echo -n test | sha256sum
-        test_single_hash<HashGenerator::HashType::SHA256>(
-            bytes,
-            "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08");
-        test_increment_hash<HashGenerator::HashType::SHA256>(
-            bytes,
-            "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08");
-    }
-
-    SECTION("Git") {
-        // same as: echo -n test | git hash-object --stdin
-        test_single_hash<HashGenerator::HashType::GIT>(
-            bytes, "30d74d258442c7c65512eafab474568dd706c430");
-    }
-}
diff --git a/test/buildtool/crypto/hash_function.test.cpp b/test/buildtool/crypto/hash_function.test.cpp
index b56c82a6..2655d7a4 100644
--- a/test/buildtool/crypto/hash_function.test.cpp
+++ b/test/buildtool/crypto/hash_function.test.cpp
@@ -19,7 +19,7 @@ TEST_CASE("Hash Function", "[crypto]") {
 
         auto hasher = HashFunction::Hasher();
         hasher.Update(bytes);
-        CHECK(std::move(hasher).Finalize()->HexString() ==  // NOLINT
+        CHECK(std::move(hasher).Finalize().HexString() ==  // NOLINT
               "a94a8fe5ccb19ba61c4c0873d391e987982fbbd3");
     }
 
@@ -40,7 +40,7 @@ TEST_CASE("Hash Function", "[crypto]") {
         auto hasher = HashFunction::Hasher();
         hasher.Update(bytes);
         CHECK(
-            std::move(hasher).Finalize()->HexString() ==  // NOLINT
+            std::move(hasher).Finalize().HexString() ==  // NOLINT
             "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08");
     }
 }
diff --git a/test/buildtool/crypto/hasher.test.cpp b/test/buildtool/crypto/hasher.test.cpp
new file mode 100644
index 00000000..01a5cb12
--- /dev/null
+++ b/test/buildtool/crypto/hasher.test.cpp
@@ -0,0 +1,28 @@
+#include "catch2/catch.hpp"
+#include "src/buildtool/crypto/hasher.hpp"
+
+template <Hasher::HashType type>
+void test_increment_hash(std::string const& bytes, std::string const& result) {
+    Hasher hasher{type};
+    hasher.Update(bytes.substr(0, bytes.size() / 2));
+    hasher.Update(bytes.substr(bytes.size() / 2));
+    auto digest = std::move(hasher).Finalize();
+    CHECK(digest.HexString() == result);
+}
+
+TEST_CASE("Hasher", "[crypto]") {
+    std::string bytes{"test"};
+
+    SECTION("SHA-1") {
+        // same as: echo -n test | sha1sum
+        test_increment_hash<Hasher::HashType::SHA1>(
+            bytes, "a94a8fe5ccb19ba61c4c0873d391e987982fbbd3");
+    }
+
+    SECTION("SHA-256") {
+        // same as: echo -n test | sha256sum
+        test_increment_hash<Hasher::HashType::SHA256>(
+            bytes,
+            "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08");
+    }
+}