From b6175d2a8b49a8d4c79d24143b3040736b63e571 Mon Sep 17 00:00:00 2001
From: Christian Rorvik <christian@graystonetrading.com>
Date: Wed, 10 Jul 2024 11:21:41 +0200
Subject: [PATCH] Regex support

---
 src/representations.jl       | 19 +++++++++++++++++++
 test/representation_tests.jl | 12 ++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/src/representations.jl b/src/representations.jl
index a1934bf..8a4d772 100644
--- a/src/representations.jl
+++ b/src/representations.jl
@@ -20,6 +20,25 @@ struct DefaultBSONConversions <: BSONConversionRules end
 @inline bson_representation_convert(::Type{Vector{UInt8}}, x::BSONBinary) = x.data
 @inline bson_representation_convert(::Type{BSONBinary}, x::Vector{UInt8}) = BSONBinary(x)
 
+# NOTE: no public API for this, hopefully this  doesn't break too often
+function regex_opts_str_(x::Regex)
+    o1 = Base.regex_opts_str(x.compile_options & ~Base.DEFAULT_COMPILER_OPTS)
+    o2 = Base.regex_opts_str(x.match_options & ~Base.DEFAULT_MATCH_OPTS)
+    o1 * o2
+end
+# Alternative implementation should the former start breaking
+# function regex_opts_str_(r::Regex)
+#     s = string(r)
+#     s[findlast(x -> x == '"', s)+1:end]
+# end
+
+@inline bson_representation_type(::Type{Regex}) = BSONRegex
+@inline bson_representation_convert(::Type{Regex}, x::BSONRegex) = Regex(x.pattern, x.options)
+@inline bson_representation_convert(::Type{BSONRegex}, x::Regex) = BSONRegex(
+    x.pattern,
+    regex_opts_str_(x)
+)
+
 @inline bson_representation_type(::Type{<:IPAddr}) = String
 @inline bson_representation_type(::Type{<:Sockets.InetAddr}) = String
 
diff --git a/test/representation_tests.jl b/test/representation_tests.jl
index 930d7ee..04e0226 100644
--- a/test/representation_tests.jl
+++ b/test/representation_tests.jl
@@ -96,4 +96,16 @@ end
     @test BSONReader(buf, StrictBSONValidator(), NumericBSONConversions())["x"][Float32] == x
 end
 
+@testset "Regex" for x in [
+    r"test",
+    r"test"i,
+    r"^foo$",
+]
+    buf = empty!(fill(0xff, 1000))
+    writer = BSONWriter(buf)
+    writer["x"] = x
+    close(writer)
+    @test BSONReader(buf, StrictBSONValidator())["x"][Regex] == x
+end
+
 end