Merge #18468: Span improvements

26acc8dd9b512f220c1facdba2c5de7976d3c258 Add sanity check asserts to span when -DDEBUG (Pieter Wuille)
2676aeadfa0e43dcaaccc4720623cdfe0beed528 Simplify usage of Span in several places (Pieter Wuille)
ab303a16d114b1e94c6cf0e4c5db5389dfa197f6 Add Span constructors for arrays and vectors (Pieter Wuille)
bb3d38fc061d8482e68cd335a45c9cd8bb66a475 Make pointer-based Span construction safer (Pieter Wuille)
1f790a1147ad9a5fe06987d84b6cd71f91cbec4b Make Span size type unsigned (Pieter Wuille)

Pull request description:

  This improves our Span class by making it closer to the C++20 `std::span` one:
  * ~~Support conversion between compatible Spans (e.g. `Span<char>` to `Span<const char>`).~~ (done in #18591)
  * Make the size type `std::size_t` rather than `std::ptrdiff_t` (the C++20 one underwent the same change).
  * Support construction of Spans directly from arrays, `std::string`s, `std::array`s, `std::vector`s, `prevector`s, ... (for all but arrays, this only works for const containers to prevent surprises).

  And then make use of those improvements in various call sites.

  I realize the template magic used looks scary, but it's only needed to make overload resultion make the right choices. Note that the operations done on values are all extremely simple: no casts, explicit conversions, or warning-silencing constructions. That should hopefully make it simpler to review.

ACKs for top commit:
  laanwj:
    Code review ACK 26acc8dd9b512f220c1facdba2c5de7976d3c258
  promag:
    Code review ACK 26acc8dd9b512f220c1facdba2c5de7976d3c258.

Tree-SHA512: 5a5bd346a140edf782b5b3b3f04d9160c7b9e9def35159814a07780ab1dd352545b88d3cc491e0f80d161f829c49ebfb952fddc9180f1a56f1257aa51f38788a

3 files changed, 14 insertions, 14 deletions

diff --git a/src/test/fuzz/span.cpp b/src/test/fuzz/span.cpp
index 4aea530ef..f6b6e8f6f 100644
--- a/src/test/fuzz/span.cpp
+++ b/src/test/fuzz/span.cpp
@@ -18,7 +18,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
     FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
 
     std::string str = fuzzed_data_provider.ConsumeBytesAsString(32);
-    const Span<const char> span = MakeSpan(str);
+    const Span<const char> span{str};
     (void)span.data();
     (void)span.begin();
     (void)span.end();
@@ -32,7 +32,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
     }
 
     std::string another_str = fuzzed_data_provider.ConsumeBytesAsString(32);
-    const Span<const char> another_span = MakeSpan(another_str);
+    const Span<const char> another_span{another_str};
     assert((span <= another_span) != (span > another_span));
     assert((span == another_span) != (span != another_span));
     assert((span >= another_span) != (span < another_span));
diff --git a/src/test/fuzz/spanparsing.cpp b/src/test/fuzz/spanparsing.cpp
index 8e5e7dad1..e5bf5dd60 100644
--- a/src/test/fuzz/spanparsing.cpp
+++ b/src/test/fuzz/spanparsing.cpp
@@ -12,7 +12,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
     const size_t query_size = fuzzed_data_provider.ConsumeIntegral<size_t>();
     const std::string query = fuzzed_data_provider.ConsumeBytesAsString(std::min<size_t>(query_size, 1024 * 1024));
     const std::string span_str = fuzzed_data_provider.ConsumeRemainingBytesAsString();
-    const Span<const char> const_span = MakeSpan(span_str);
+    const Span<const char> const_span{span_str};
 
     Span<const char> mut_span = const_span;
     (void)spanparsing::Const(query, mut_span);
diff --git a/src/test/util_tests.cpp b/src/test/util_tests.cpp
index cf26ca3ad..257328974 100644
--- a/src/test/util_tests.cpp
+++ b/src/test/util_tests.cpp
@@ -1829,7 +1829,7 @@ BOOST_AUTO_TEST_CASE(test_spanparsing)
 
     // Const(...): parse a constant, update span to skip it if successful
     input = "MilkToastHoney";
-    sp = MakeSpan(input);
+    sp = input;
     success = Const("", sp); // empty
     BOOST_CHECK(success);
     BOOST_CHECK_EQUAL(SpanToStr(sp), "MilkToastHoney");
@@ -1854,7 +1854,7 @@ BOOST_AUTO_TEST_CASE(test_spanparsing)
 
     // Func(...): parse a function call, update span to argument if successful
     input = "Foo(Bar(xy,z()))";
-    sp = MakeSpan(input);
+    sp = input;
 
     success = Func("FooBar", sp);
     BOOST_CHECK(!success);
@@ -1877,31 +1877,31 @@ BOOST_AUTO_TEST_CASE(test_spanparsing)
     Span<const char> result;
 
     input = "(n*(n-1))/2";
-    sp = MakeSpan(input);
+    sp = input;
     result = Expr(sp);
     BOOST_CHECK_EQUAL(SpanToStr(result), "(n*(n-1))/2");
     BOOST_CHECK_EQUAL(SpanToStr(sp), "");
 
     input = "foo,bar";
-    sp = MakeSpan(input);
+    sp = input;
     result = Expr(sp);
     BOOST_CHECK_EQUAL(SpanToStr(result), "foo");
     BOOST_CHECK_EQUAL(SpanToStr(sp), ",bar");
 
     input = "(aaaaa,bbbbb()),c";
-    sp = MakeSpan(input);
+    sp = input;
     result = Expr(sp);
     BOOST_CHECK_EQUAL(SpanToStr(result), "(aaaaa,bbbbb())");
     BOOST_CHECK_EQUAL(SpanToStr(sp), ",c");
 
     input = "xyz)foo";
-    sp = MakeSpan(input);
+    sp = input;
     result = Expr(sp);
     BOOST_CHECK_EQUAL(SpanToStr(result), "xyz");
     BOOST_CHECK_EQUAL(SpanToStr(sp), ")foo");
 
     input = "((a),(b),(c)),xxx";
-    sp = MakeSpan(input);
+    sp = input;
     result = Expr(sp);
     BOOST_CHECK_EQUAL(SpanToStr(result), "((a),(b),(c))");
     BOOST_CHECK_EQUAL(SpanToStr(sp), ",xxx");
@@ -1910,7 +1910,7 @@ BOOST_AUTO_TEST_CASE(test_spanparsing)
     std::vector<Span<const char>> results;
 
     input = "xxx";
-    results = Split(MakeSpan(input), 'x');
+    results = Split(input, 'x');
     BOOST_CHECK_EQUAL(results.size(), 4U);
     BOOST_CHECK_EQUAL(SpanToStr(results[0]), "");
     BOOST_CHECK_EQUAL(SpanToStr(results[1]), "");
@@ -1918,19 +1918,19 @@ BOOST_AUTO_TEST_CASE(test_spanparsing)
     BOOST_CHECK_EQUAL(SpanToStr(results[3]), "");
 
     input = "one#two#three";
-    results = Split(MakeSpan(input), '-');
+    results = Split(input, '-');
     BOOST_CHECK_EQUAL(results.size(), 1U);
     BOOST_CHECK_EQUAL(SpanToStr(results[0]), "one#two#three");
 
     input = "one#two#three";
-    results = Split(MakeSpan(input), '#');
+    results = Split(input, '#');
     BOOST_CHECK_EQUAL(results.size(), 3U);
     BOOST_CHECK_EQUAL(SpanToStr(results[0]), "one");
     BOOST_CHECK_EQUAL(SpanToStr(results[1]), "two");
     BOOST_CHECK_EQUAL(SpanToStr(results[2]), "three");
 
     input = "*foo*bar*";
-    results = Split(MakeSpan(input), '*');
+    results = Split(input, '*');
     BOOST_CHECK_EQUAL(results.size(), 4U);
     BOOST_CHECK_EQUAL(SpanToStr(results[0]), "");
     BOOST_CHECK_EQUAL(SpanToStr(results[1]), "foo");