1 files changed, 72 insertions, 0 deletions
diff --git a/tests/d2s_intrinsics_test.rs b/tests/d2s_intrinsics_test.rs
new file mode 100644
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+++ b/tests/d2s_intrinsics_test.rs
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+// Translated from C to Rust. The original C code can be found at
+// https://github.com/ulfjack/ryu and carries the following license:
+//
+// Copyright 2018 Ulf Adams
+//
+// The contents of this file may be used under the terms of the Apache License,
+// Version 2.0.
+//
+//    (See accompanying file LICENSE-Apache or copy at
+//     http://www.apache.org/licenses/LICENSE-2.0)
+//
+// Alternatively, the contents of this file may be used under the terms of
+// the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE-Boost or copy at
+//     https://www.boost.org/LICENSE_1_0.txt)
+//
+// Unless required by applicable law or agreed to in writing, this software
+// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.
+
+#![allow(dead_code)]
+#![allow(
+    clippy::cast_lossless,
+    clippy::cast_possible_truncation,
+    clippy::unreadable_literal
+)]
+
+#[path = "../src/d2s_intrinsics.rs"]
+mod d2s_intrinsics;
+
+use d2s_intrinsics::pow5_factor;
+
+#[test]
+fn test_pow5_factor() {
+    assert_eq!(0, pow5_factor(1));
+    assert_eq!(0, pow5_factor(2));
+    assert_eq!(0, pow5_factor(3));
+    assert_eq!(0, pow5_factor(4));
+    assert_eq!(1, pow5_factor(5));
+    assert_eq!(0, pow5_factor(6));
+    assert_eq!(0, pow5_factor(7));
+    assert_eq!(0, pow5_factor(8));
+    assert_eq!(0, pow5_factor(9));
+    assert_eq!(1, pow5_factor(10));
+
+    assert_eq!(0, pow5_factor(12));
+    assert_eq!(0, pow5_factor(14));
+    assert_eq!(0, pow5_factor(16));
+    assert_eq!(0, pow5_factor(18));
+    assert_eq!(1, pow5_factor(20));
+
+    assert_eq!(2, pow5_factor(5 * 5));
+    assert_eq!(3, pow5_factor(5 * 5 * 5));
+    assert_eq!(4, pow5_factor(5 * 5 * 5 * 5));
+    assert_eq!(5, pow5_factor(5 * 5 * 5 * 5 * 5));
+    assert_eq!(6, pow5_factor(5 * 5 * 5 * 5 * 5 * 5));
+    assert_eq!(7, pow5_factor(5 * 5 * 5 * 5 * 5 * 5 * 5));
+    assert_eq!(8, pow5_factor(5 * 5 * 5 * 5 * 5 * 5 * 5 * 5));
+    assert_eq!(9, pow5_factor(5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5));
+    assert_eq!(10, pow5_factor(5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5));
+
+    assert_eq!(0, pow5_factor(42));
+    assert_eq!(1, pow5_factor(42 * 5));
+    assert_eq!(2, pow5_factor(42 * 5 * 5));
+    assert_eq!(3, pow5_factor(42 * 5 * 5 * 5));
+    assert_eq!(4, pow5_factor(42 * 5 * 5 * 5 * 5));
+    assert_eq!(5, pow5_factor(42 * 5 * 5 * 5 * 5 * 5));
+
+    assert_eq!(27, pow5_factor(7450580596923828125)); // 5^27, largest power of 5 < 2^64.
+    assert_eq!(1, pow5_factor(18446744073709551615)); // 2^64 - 1, largest multiple of 5 < 2^64.
+    assert_eq!(0, pow5_factor(18446744073709551614)); // 2^64 - 2, largest non-multiple of 5 < 2^64.
+}